PROTHENA CORP PUBLIC LTD CO (Form: 10-Q, Received: 11/04/2021 16:43:42)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

______________________________________

FORM 10-Q

_____________________________________

(Mark One)


☒			QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended September 30,2021


☐			TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Commission file number: 001-35676

______________________________________

PROTHENA CORPORATION PUBLIC LIMITED COMPANY

(Exact name of registrant as specified in its charter)

______________________________________


Ireland						98-1111119
(State or other jurisdiction of incorporation or organization)						(I.R.S. Employer Identification Number)


77 Sir John Rogerson’s Quay, Block C
Grand Canal Docklands
Dublin 2,	D02 VK60,	Ireland
(Address of principal executive offices including Zip Code)

Registrant’s telephone number, including area code: 011-353-1-236-2500

______________________________________

Securities registered pursuant to Section 12(b) of the Act:


Title of Each Class	Trading Symbol	Name of Each Exchange on Which Registered
Ordinary Shares, par value $0.01 per share	PRTA	The Nasdaq Global Select Market

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.


Large accelerated filer	☐	Accelerated filer	☐
Non-accelerated filer	☒	Smaller reporting company	☒
		Emerging growth company	☐
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.			☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The number of ordinary shares outstanding was 46,593,782 as of October 28, 2021.

PROTHENA CORPORATION PLC

Form 10-Q – QUARTERLY REPORT

For the Quarter Ended September 30, 2021

TABLE OF CONTENTS


			Page

PART I. FINANCIAL INFORMATION			1
Item 1. Financial Statements (unaudited)			1
Condensed Consolidated Balance Sheets as of September 30, 2021 and December 31, 2020			1
Condensed Consolidated Statements of Operations for the three and nine months ended September 30, 2021 and 2020			2
Condensed Consolidated Statements of Cash Flows for the nine months ended September 30, 2021 and 2020			3
Condensed Consolidated Statements of Shareholders' Equity for the three and nine months ended September 30, 2021 and 2020			5
Notes to Condensed Consolidated Financial Statements			7
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations			26
Item 3. Quantitative and Qualitative Disclosures About Market Risk			35
Item 4. Controls and Procedures			36

PART II. OTHER INFORMATION			37
Item 1. Legal Proceedings			37
Item 1A. Risk Factors			37
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds			70
Item 3. Defaults Upon Senior Securities			70
Item 4. Mine Safety Disclosures			70
Item 5. Other Information			71
Item 6. Exhibits			72

SIGNATURES			74

EXHIBIT INDEX			72

Note Regarding Forward-Looking Statements

In addition to historical information, this Quarterly Report on Form 10-Q contains forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements may include words such as “aim,” “anticipate,” “assume,” “believe,” “contemplate,” “continue,” “could,” “due,” “estimate,” “expect,” “goal,” “intend,” “may,” “objective” “plan,” “predict,” “potential,” “positioned,” “seek,” “should,” “target,” “will,” “would,” and other similar expressions that are predictions of or indicate future events and future trends, or the negative of these terms or other comparable terminology. In addition, any statements that refer to expectations, projections, or other characterizations of future events or circumstances are forward-looking statements.

These forward-looking statements, which reflect our beliefs, assumptions, expectations, estimates, forecasts, and projections about our business and the industry in which we operated as of the date hereof, are estimates based on our best judgment. These statements relate to, among other things, our goal of building a protein dysregulation platform; the treatment potential and proposed mechanisms of action of drug candidates; plans for future clinical studies of our drug candidates; our collaborations with Roche and Bristol Myers Squibb and amounts we may receive under such collaborations; the sufficiency of our cash position to fund advancement of a broad pipeline; and our anticipated need for additional capital.

These forward-looking statements are not guarantees of future performance or development and involve known and unknown risks, uncertainties, and other factors that are in some cases beyond our control. As a result, any or all of our forward-looking statements in this Quarterly Report on Form 10-Q may turn out to be inaccurate. Factors that could cause our actual results to differ materially include, but are not limited to, the risks and uncertainties set forth below, those discussed under Part II Item 1A “Risk Factors” of this Quarterly Report on Form 10-Q, and in our other filings with the U.S. Securities and Exchange Commission:

•our ability to obtain additional financing in future offerings and/or obtain funding from future collaborations;

•our operating losses;

•our ability to successfully complete research and development of our drug candidates;

•our ability to develop, manufacture and commercialize products;

•our collaborations and other agreements with third parties, including Roche, Bristol Myers Squibb, and Novo Nordisk;

•our ability to protect our patents and other intellectual property;

•our ability to hire and retain key employees;

•our ability to maintain financial flexibility and sufficient cash, cash equivalents and investments and other assets capable of being monetized to meet our liquidity requirements;

•the timing, receipt, and amount of any capital investments, cost-sharing contributions or reimbursements, milestone payments, or royalties that we might receive under current or potential future collaborations, including any milestone payments pursuant to our agreement with Novo Nordisk;

•potential disruptions in the U.S. and global capital and credit markets;

•government regulation of our industry;

•the volatility of the market price of our ordinary shares;

•the outbreak of the novel strain of coronavirus SARS-CoV-2 and the emergence of variant strains; and

•business disruptions.

Except as required by law or by the rules and regulations of the U.S. Securities and Exchange Commission, we undertake no obligation to revise or update any forward-looking statements to reflect any event or circumstance that arises after the date of this Quarterly Report on Form 10-Q.

Summary of Risks Affecting Our Business

Our business is subject to numerous risks and uncertainties. The following summary highlights some of the risks you should consider with respect to our business and prospects. These risks are described more fully in Part II Item 1A “Risk Factors” of this Quarterly Report on Form 10-Q which includes a more complete discussion of the risks summarized below as well as a discussion of other risks related to our business, our prospects, and your investment in our ordinary shares.

•We anticipate that we will incur losses for the foreseeable future and we may never sustain profitability.

•We will require additional capital to fund our operations, and if we are unable to obtain such capital, we will be unable to successfully develop and commercialize drug candidates.

•The COVID-19 pandemic has adversely affected our business and could have a material adverse effect on our liquidity, results of operations, financial condition, or business, including our nonclinical and clinical development programs.

•Our success is largely dependent on the success of our research and development programs; our drug candidates are in various stages of development and we may not be able to successfully discover, develop, obtain regulatory approval for, or commercialize any drug candidates.

•We have entered into collaborations with Roche and Bristol Myers Squibb and may enter into additional collaborations in the future, and we might not realize the anticipated benefits of such collaborations or other agreements involving milestone payments, such as our agreement with Novo Nordisk.

•If clinical trials of our drug candidates are prolonged, delayed, suspended, or terminated, we may be unable to commercialize our drug candidates on a timely basis, which would require us to incur additional costs and delay our receipt of any revenue from potential product sales.

•Even if any of our drug candidates receives regulatory approval, if such approved product does not achieve broad market acceptance, the revenues that we generate from sales of the product will be limited.

•If we are unable to adequately protect or enforce the intellectual property relating to our drug candidates our ability to successfully commercialize our drug candidates will be harmed.

•Our future success depends on our ability to retain key personnel and to attract, retain, and motivate qualified personnel.

PART I. FINANCIAL INFORMATION

ITEM 1. FINANCIAL STATEMENTS

Prothena Corporation plc and Subsidiaries

Condensed Consolidated Balance Sheets (unaudited)

(in thousands, except share and per share data)


	September 30,		December 31,
	2021		2020
Assets
Current assets:
Cash and cash equivalents	$	600,098	$	295,380
Accounts receivable	79		15
Prepaid expenses and other current assets	7,353		2,537
Restricted cash, current	—		1,352
Total current assets	607,530		299,284
Non-current assets:
Property and equipment, net	1,944		2,551
Operating lease right-of-use assets	13,567		17,811
Deferred tax assets	6,503		11,644
Restricted cash, non-current	1,352		1,352
Other non-current assets	1,808		333
Total non-current assets	25,174		33,691
Total assets	$	632,704	$	332,975
Liabilities and Shareholders’ Equity
Current liabilities:
Accounts payable	$	3,483	$	4,117
Accrued research and development	5,315		9,044
Income taxes payable, current	—		36
Deferred revenue, current	7,205		—
Lease liability, current	5,831		5,512
Other current liabilities	7,367		7,139
Total current liabilities	29,201		25,848
Non-current liabilities:
Deferred revenue, non-current	104,557		110,242
Lease liability, non-current	7,922		12,326
Other liabilities	553		553
Total non-current liabilities	113,032		123,121
Total liabilities	142,233		148,969
Commitments and contingencies (Note 6)
Shareholders’ equity:
Euro deferred shares, €22 nominal value:	—		—
Authorized shares — 10,000 at September 30, 2021 and December 31, 2020
Issued and outstanding shares — none at September 30, 2021 and December 31, 2020
Ordinary shares, $0.01 par value:	465		399
Authorized shares — 100,000,000 at September 30, 2021 and December 31, 2020
Issued and outstanding shares — 46,533,247 and 39,921,413 at September 30, 2021 and December 31, 2020, respectively
Additional paid-in capital	1,172,881		966,636
Accumulated deficit	(682,875)		(783,029)
Total shareholders’ equity	490,471		184,006
Total liabilities and shareholders’ equity	$	632,704	$	332,975

See accompanying Notes to Condensed Consolidated Financial Statements.

Prothena Corporation plc and Subsidiaries

Condensed Consolidated Statements of Operations

(in thousands, except per share data)

(unaudited)


	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Collaboration revenue	78,480		$	157	$	138,661	$	443
Revenue from license and intellectual property	60,694		—		60,744		50
Total revenue	139,174		157		199,405		493
Operating expenses:
Research and development	17,992		21,605		60,226		54,124
General and administrative	11,955		9,398		34,112		28,795
Total operating expenses	29,947		31,003		94,338		82,919
Income (loss) from operations	109,227		(30,846)		105,067		(82,426)
Other income (expense):
Interest income	11		43		30		1,359
Other income (expense), net	(42)		11		(80)		3
Total other income (expense), net	(31)		54		(50)		1,362
Income (loss) before income taxes	109,196		(30,792)		105,017		(81,064)
Provision for (benefit from) income taxes	(51)		(215)		4,863		(636)
Net income (loss)	$	109,247	$	(30,577)	$	100,154	$	(80,428)
Basic net income (loss) per ordinary share	$	2.39	$	(0.77)	$2.31		($2.02)
Diluted net income (loss) per ordinary share	$	2.13	$	(0.77)	$2.12		($2.02)
Shares used to compute basic net income (loss) per share	45,626		39,917		43,422		39,912
Shares used to compute diluted net income (loss) per share	51,205		39,917		47,196		39,912

See accompanying Notes to Condensed Consolidated Financial Statements.

Prothena Corporation plc and Subsidiaries

Condensed Consolidated Statements of Cash Flows

(in thousands)

(unaudited)


	Nine Months Ended September 30,
	2021		2020
Operating activities
Net income (loss)	$	100,154	$	(80,428)
Adjustments to reconcile net income (loss) to cash provided by (used in) operating activities:
Depreciation and amortization	875		1,152
Share-based compensation	17,771		16,806
Deferred income taxes	5,141		(1,568)
Amortization of right-of-use assets	4,244		4,077
Changes in operating assets and liabilities:
Accounts receivable	(64)		46
Prepaid and other assets	(6,291)		(1,244)
Accounts payable, accruals and other liabilities	(4,202)		3,669
Operating lease liabilities	(4,085)		(3,778)
Deferred revenues	1,520		—
Net cash provided by (used in) operating activities	115,063		(61,268)
Investing activities
Purchases of property and equipment	(256)		(145)
Net cash used in investing activities	(256)		(145)
Financing activities
Proceeds from issuance of ordinary shares in public offering, net	78,049		—
Proceeds from issuance of ordinary shares in at-the market offering, net	96,816		—
Proceeds from issuance of ordinary shares upon exercise of stock options	13,694		215
Net cash provided by financing activities	188,559		215
Net increase (decrease) in cash, cash equivalents and restricted cash	303,366		(61,198)
Cash, cash equivalents and restricted cash, beginning of the year	298,084		378,427
Cash, cash equivalents and restricted cash, end of the period	$	601,450	$	317,229

Supplemental disclosures of cash flow information
Cash paid for income taxes, net	$	568	$	672

Supplemental disclosures of non-cash investing and financing activities
Acquisition of property and equipment included in accounts payable and accrued liabilities	$	11	$	37
At-the market offering costs included in accounts payable and accrued liabilities	$	19	$	—

See accompanying Notes to Condensed Consolidated Financial Statements.

The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the statement of financial position that sum to the total of the same such amounts shown in the Condensed Consolidated Statements of Cash Flows.


	Nine Months Ended September 30,
	2021		2020
Cash and cash equivalents	$	600,098	$	314,525
Restricted cash, current	—		1,352
Restricted cash, non-current	1,352		1,352
Total cash, cash equivalents and restricted cash, end of the period	$	601,450	$	317,229

Prothena Corporation plc and Subsidiaries

Condensed Consolidated Statements of Shareholders' Equity

(in thousands, except share data)

(unaudited)


	Three Months Ended September 30, 2021
	Ordinary Shares			Additional Paid-in Capital		Accumulated Deficit		Total Shareholders' Equity
	Shares	Amount
Balances at June 30, 2021	44,913,024	$	449	$	1,079,880	$	(792,122)	$	288,207
Share-based compensation				6,055				6,055
Issuance of ordinary shares upon exercise of stock options	292,045	3		4,129				4,132
Issuance of ordinary shares in at-the-market offering, net of issuance costs of $2.7 million.	1,328,178	13		82,817				82,830
Net income						109,247		109,247
Balances at September 30, 2021	46,533,247	$	465	$	1,172,881	$	(682,875)	$	490,471


	Three Months Ended September 30, 2020
	Ordinary Shares			Additional Paid-in Capital		Accumulated Deficit		Total Shareholders' Equity
	Shares	Amount
Balances at June 30, 2020	39,911,413	399		955,781		(721,736)		234,444
Share-based compensation				5,583				5,583
Issuance of ordinary shares upon exercise of stock options	10,000	—		64				64
Net loss						(30,577)		(30,577)
Balances at September 30, 2020	39,921,413	$	399	$	961,428	$	(752,313)	$	209,514


	Nine Months Ended September 30, 2021
	Ordinary Shares			Additional Paid-in Capital		Accumulated Deficit		Total Shareholders' Equity
	Shares	Amount
Balances at December 31, 2020	39,921,413	$	399	$	966,636	$	(783,029)	$	184,006
Share-based compensation				17,771				17,771
Issuance of ordinary shares upon exercise of stock options	946,660	10		13,684				13,694
Issuance of ordinary shares in public offering, net of issuance costs of $5.5 million	4,025,000	40		78,009				78,049
Issuance of ordinary shares under the at-the-market offering program, net of issuance costs of $3.2 million	1,640,174	16		96,781				96,797
Net income						100,154		100,154
Balances at September 30, 2021	46,533,247	$	465	$	1,172,881	$	(682,875)	$	490,471


	Nine Months Ended September 30, 2020
	Ordinary Shares			Additional Paid-in Capital		Accumulated Deficit		Total Shareholders' Equity
	Shares	Amount
Balances at December 31, 2019	39,898,561	399		944,407		(671,885)		272,921
Share-based compensation				16,806				16,806
Issuance of ordinary shares upon exercise of stock options	22,852			215				215
Net loss						(80,428)		(80,428)
Balances at September 30, 2020	39,921,413	$	399	$	961,428	$	(752,313)	$	209,514

See accompanying Notes to Consolidated Financial Statements.

Notes to the Condensed Consolidated Financial Statements

(unaudited)

1.Organization

Description of Business

Prothena Corporation plc (“Prothena” or the “Company”) is a late-stage clinical company with a robust pipeline of novel investigational therapeutics built on protein dysregulation expertise with the potential to change the course of devastating rare peripheral amyloid and neurodegenerative diseases.

Fueled by its deep scientific expertise built over decades of research, the Company is advancing a pipeline of therapeutic candidates for a number of indications and novel targets for which its ability to integrate scientific insights around neurological dysfunction and the biology of misfolded proteins can be leveraged. The Company’s wholly-owned programs include birtamimab for the potential treatment of AL amyloidosis, and a portfolio of programs for the potential treatment of Alzheimer’s disease including PRX012 which targets Aβ (Amyloid beta) and a novel dual Aβ-Tau vaccine. The Company’s partnered programs include prasinezumab, in collaboration with Roche for the potential treatment of Parkinson’s disease and other related synucleinopathies, and programs that target tau (PRX005), TDP-43 and an undisclosed target in collaboration with Bristol Myers Squibb for the potential treatment of Alzheimer’s disease, amyotrophic lateral sclerosis (ALS).

The Company was formed on September 26, 2012, under the laws of Ireland and re-registered as an Irish public limited company on October 25, 2012. The Company's ordinary shares began trading on The Nasdaq Global Market under the symbol “PRTA” on December 21, 2012, and currently trade on The Nasdaq Global Select Market.

Liquidity and Business Risks

As of September 30, 2021, the Company had an accumulated deficit of $682.9 million and cash and cash equivalents of $600.1 million.

In March 2021, the Company sold an aggregate of 4,025,000 ordinary shares for net proceeds of approximately $78.0 million, after deducting the underwriting discount and estimated offering expenses, in an underwritten public offering. In May 2021, the Company initiated an at-the-market offering program ("ATM"), which allows the Company to sell and issue shares of the Company's ordinary shares from time-to-time. The Company has issued 1,640,174 ordinary shares, for net proceeds of approximately $96.8 million through September 30, 2021.

Based on the Company's business plans, management believes that the Company’s cash and cash equivalents at September 30, 2021, are sufficient to meet its obligations for at least the next twelve months. To operate beyond such period, or if the Company elects to increase its spending on research and development programs significantly above current long-term plans or enters into potential licenses and or other acquisitions of complementary technologies, products or companies, the Company may need additional capital. The Company expects to continue to finance future cash needs that exceed its cash from operating activities primarily through its current cash and cash equivalents, its collaborations with Roche and Bristol Myers Squibb, its agreement with Novo Nordisk, and, to the extent necessary, through proceeds from public or private equity or debt financings, loans and other collaborative agreements with corporate partners or other arrangements.

2.Summary of Significant Accounting Policies

Basis of Preparation and Presentation of Financial Information

These accompanying Unaudited Interim Condensed Consolidated Financial Statements have been prepared in accordance with the accounting principles generally accepted in the U.S. (“GAAP”) and with the instructions for Form 10-Q and Regulation S-X statements. Accordingly, they do not include all of the information and notes required for complete financial statements. These interim Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and Notes thereto contained in the Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission (the “SEC”) on February 26, 2021 (the “2020 Form 10-K”). These Unaudited Interim Condensed Consolidated Financial Statements are presented in U.S. dollars, which is the functional currency of the Company and its consolidated subsidiaries. These Unaudited Interim Condensed Consolidated Financial Statements include the accounts of the Company and its consolidated subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

Unaudited Interim Financial Information

The accompanying Unaudited Interim Condensed Consolidated Financial Statements and related disclosures are unaudited, have been prepared on the same basis as the annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair presentation of the results of operations for the periods presented. The year-end condensed consolidated balance sheet data was derived from audited financial statements, however certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted. The condensed consolidated results of operations for any interim period are not necessarily indicative of the results to be expected for the full year or for any other future year or interim period.

Use of Estimates

The preparation of the Condensed Consolidated Financial Statements in conformity with GAAP requires management to make judgments, estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosures. On an ongoing basis, management evaluates its estimates, including critical accounting policies or estimates related to revenue recognition, share-based compensation, research and development expenses and leases. The Company bases its estimates on historical experience and on various other market specific and other relevant assumptions that management believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Because of the uncertainties inherent in such estimates, actual results may differ materially from these estimates.

Significant Accounting Policies

There were no significant changes to the accounting policies during the nine months ended September 30, 2021, from the significant accounting policies described in Note 2 of the Notes to Consolidated Financial Statements in the 2020 Form 10-K.

Segment and Concentration of Risks

The Company operates in one segment. The Company’s chief operating decision maker (the “CODM”), its Chief Executive Officer, manages the Company’s operations on a consolidated basis for purposes of allocating resources. When evaluating the Company’s financial performance, the CODM reviews all financial information on a consolidated basis.

Financial instruments that potentially subject the Company to concentration of credit risk consist of cash and cash equivalents and accounts receivable. The Company places its cash equivalents with high credit quality financial institutions and, by policy, limits the amount of credit exposure with any one financial institution. Deposits held with banks may exceed the amount of insurance provided on such deposits. The Company has not experienced any losses on its deposits of cash and cash equivalents and its credit risk exposure is up to the extent recorded on the Company's Consolidated Balance Sheet.

The receivables recorded in the Condensed Consolidated Balance Sheet as of September 30, 2021 include amounts due from a Novo Nordisk entity located in Denmark. The Company's credit risk exposure is up to the extent recorded on the Company's Condensed Consolidated Balance Sheet.

As of September 30, 2021, $1.9 million of the Company’s property and equipment, net were held in the U.S. and a nominal amount were in Ireland. As of December 31, 2020, $2.6 million of the Company's property and equipment, net were held in the U.S. and nominal were in Ireland.

The Company does not own or operate facilities for the manufacture, packaging, labeling, storage, testing or distribution of nonclinical or clinical supplies of any of its drug candidates. The Company instead contracts with and relies on third-parties to manufacture, package, label, store, test and distribute all preclinical development and clinical supplies of our drug candidates, and it plans to continue to do so for the foreseeable future. The Company also relies on third-party consultants to assist in managing these third-parties and assist with its manufacturing strategy.

Recent Accounting Pronouncements

There were no new accounting pronouncements or changes to accounting pronouncements during the nine months ended September 30, 2021 that are of significance or potential significance to the Company.

3.Fair Value Measurements

The Company measures certain financial assets and liabilities at fair value on a recurring basis, including cash equivalents. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. A three-tier fair value hierarchy is established as a basis for considering such assumptions and for inputs used in the valuation methodologies in measuring fair value:

Level 1 — Observable inputs such as quoted prices (unadjusted) for identical assets or liabilities in active markets.

Level 2 — Include other inputs that are based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-based valuation techniques for which all significant inputs are observable in the market or can be derived from observable market data. Where applicable, these models project future cash flows and discount the future amounts to a present value using market-based observable inputs including interest rate curves, foreign exchange rates, and credit ratings.

Level 3 — Unobservable inputs that are supported by little or no market activities, which would require the Company to develop its own assumptions.

The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The carrying amounts of certain financial instruments, such as cash equivalents, accounts receivable, accounts payable and accrued liabilities, approximate fair value due to their relatively short maturities, and low market interest rates, if applicable.

Based on the fair value hierarchy, the Company classifies its cash equivalents within Level 1. This is because the Company values its cash equivalents using quoted market prices. The Company’s Level 1 securities consisted of $510.9 million and $226.1 million in money market funds included in cash and cash equivalents at September 30, 2021, and December 31, 2020, respectively.

4.Composition of Certain Balance Sheet Items

Property and Equipment, net

Property and equipment, net consisted of the following (in thousands):


	September 30,		December 31,
	2021		2020
Machinery and equipment	$	9,464	$	9,343
Leasehold improvements	1,394		1,278
Purchased computer software	1,454		1,423
	12,312		12,044
Less: accumulated depreciation and amortization	(10,368)		(9,493)
Property and equipment, net	$	1,944	$	2,551

Depreciation expense was $0.3 million and $0.9 million for the three and nine months ended September 30, 2021, respectively, and $0.4 million and $1.2 million for the three and nine months ended September 30, 2020, respectively.

Other Current Liabilities

Other current liabilities consisted of the following (in thousands):


	September 30,		December 31
	2021		2020
Payroll and related expenses	$	6,246	$	5,927
Professional services	693		696
Other	428		516
Other current liabilities	$	7,367	$	7,139

5.Net Income (Loss) Per Ordinary Share

Basic net income (loss) per ordinary share is calculated by dividing net income (loss) by the weighted-average number of ordinary shares outstanding during the period. Shares used in diluted net income per ordinary share would include the dilutive effect of ordinary shares potentially issuable upon the exercise of stock options outstanding. However, potentially issuable ordinary shares are not used in computing diluted net loss per ordinary share as their effect would be anti-dilutive due to the loss recorded during the three and nine months ended September 30, 2020, and therefore diluted net loss per share is equal to basic net loss per share. During the three and nine months ended September 30, 2021, diluted net income per ordinary share is computed by giving effect to all dilutive potential ordinary shares including options.

Net income (loss) per ordinary share was determined as follows (in thousands, except per share amounts):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Numerator:
Net income ( loss)	$	109,247	$	(30,577)	$	100,154	$	(80,428)
Denominator:
Weighted-average ordinary shares outstanding used in per share calculations - basic	45,626		39,917		43,422		39,912
Dilutive stock options outstanding	5,579		—		3,774		—
Weighted-average ordinary shares outstanding used in per share calculations - diluted	51,205		39,917		47,196		39,912
Net income (loss) per ordinary share:
Basic	$	2.39	$	(0.77)	$	2.31	$	(2.02)
Diluted	$	2.13	$	(0.77)	$	2.12	$	(2.02)

The equivalent ordinary shares not included in diluted net income (loss) per share because their effect would be anti-dilutive are as follows (in thousands):


	Three Months Ended September 30,		Nine Months Ended September 30,
	2021	2020	2021	2020
Stock options to purchase ordinary shares	70	8,795	602	8,795

6. Commitments and Contingencies

Lease Commitments

The Company currently has three leases relating to its facilities in South San Francisco and Dublin, Ireland.

Current SSF Facility

The Company has a noncancelable operating sublease (the “Lease”) covering 128,751 square feet of office and laboratory space in South San Francisco, California, U.S. (the “Current SSF Facility”). The Lease includes a free rent period and escalating rent payments and has a remaining lease term of 2.25 years that expires on December 31, 2023, unless terminated earlier. The Company's obligation to pay rent commenced on August 1, 2016. The Company is obligated to make lease payments totaling approximately $39.2 million over the lease term. The Lease further provides that the Company is obligated to pay to the sublandlord and master landlord certain costs, including taxes and operating expenses. The Lease is considered an operating lease under ASC 842. Prior to the Company's adoption of ASC 842, this Lease was considered a build-to-suit lease.

The Company’s right-of-use asset and lease liability are determined based on the present value of minimum lease payments over the remaining lease term and the Company’s incremental borrowing rate based on information available as of January 1, 2019. The right-of-use asset also includes any lease prepayments made and excludes unamortized lease incentives including rent abatements and/or concessions and rent holidays. Tenant improvements made by the Company as a lessee, in which such improvements are deemed to be owned by the lessor, are viewed as lease prepayments by the Company and are included in the right-of-use asset. Lease expense is recognized on a straight-line basis over the expected lease term. Total operating lease cost was $1.6 million and $4.8 million for the three and nine months ended September 30, 2021, respectively, and $1.6 million and $4.8 million for the three and nine months ended September 30, 2020, respectively. Total cash paid against the operating lease liability was $1.5 million and $4.6 million for the three and nine months ended September 30, 2021, respectively, and $1.5 million and $4.5 million for the three and nine months ended September 30, 2020, respectively.

The discount rate used to determine the lease liability was 4.25%. To estimate the Company's collateralized incremental borrowing rate, the Company inquired with banks that had a business relationship with the Company. Furthermore, the Company's operating lease in Dublin is not included in the lease liability and right-of-use asset recorded due to its nominal amount. As of September 30, 2021, the Company performed an evaluation of its other contracts with customers and suppliers in accordance with ASC 842 and have determined that, except for the leases described below and a nominal operating lease for office equipment, none of the Company’s contracts contain a lease.

In connection with this Lease, the Company received a tenant improvement allowance of $14.2 million from the sublandlord and the master landlord, for the costs associated with the design, development and construction of tenant improvements for the Current SSF Facility. The Company is obligated to fund all costs incurred in excess of the tenant improvement allowance. The initial measurement of right-of-use asset for the Lease includes the tenant improvement added by the Company wherein the lessor was deemed the accounting owner, net of the tenant improvement allowance received from the sublandlord and the master landlord.

The Company obtained a standby letter of credit in April 2016 in the initial amount of $4.1 million, which may be drawn down by the sublandlord in the event the Company fails to fully and faithfully perform all of its obligations under the Lease and to compensate the sublandlord for all losses and damages the sublandlord may suffer as a result of the occurrence of any default on the part of Company not cured within the applicable cure period. This standby letter of credit is collateralized by a certificate of deposit of the same amount which is classified as restricted cash. The Company was entitled to a $1.4 million reduction in the face amount of the standby letter of credit on the third anniversary of the contractual rent commencement, which was received in 2019, and another $1.4 million on the fifth anniversary of the contractual rent commencement, which was received in September 2021. As a condition to the reduction of the standby letter of credit amount, no uncured default by the Company shall then exist under the Lease. As of September 30, 2021, none of the remaining standby letter of credit amount of $1.4 million has been used.

Sub-Sublease of Current SSF Facility

On July 18, 2018, the Company entered into a Sub-Sublease Agreement (the “Sub-Sublease”) with Assembly Biosciences, Inc. (the “Sub-Subtenant”) to sub-sublease approximately 46,641 square feet of office and laboratory space of the Current SSF Facility to the Sub-Subtenant. The Sub-Sublease is considered an operating lease under ASC 842. For the three and nine months ended September 30, 2021, the Company recorded $0.7 million and $2.2 million, respectively, and $0.7 million and $2.2 million for the three and nine months ended September 30, 2020, respectively, of sub-lease rental income as an offset to its operating expenses.

The Sub-Sublease provides for initial annual base rent for the complete Sub-Subleased Premises of approximately $2.7 million, with increases of approximately 3.5% in annual base rent on September 1, 2019, and each anniversary thereof. The Sub-Sublease rental income excludes reimbursements for executory costs received from the Sub-Subtenant. The Sub-Sublease became effective on September 24, 2018, and has a term of 5.2 years which terminates on December 15, 2023. The Sub-Sublease will terminate if the Lease or the corresponding master lease terminates. The Company or the Sub-Subtenant may elect, subject to limitations set forth in the Sub-Sublease, to terminate the Sub-Sublease following a material casualty or condemnation affecting the Subleased Premises. The Company may terminate the Sub-Sublease following an event of default, which is defined in the Sub-Sublease to include, among other things, non-payment of amounts owing by the Sub-Subtenant under the Sub-Sublease.

The Company is required under the Lease to pay to the sublandlord 50% of that portion of the cash sums and other economic consideration received from the Sub-Subtenant that exceeds the base rent paid by the Company to the sublandlord after deducting certain of the Company’s costs.

Dublin

The Company has an existing office space in Dublin, Ireland which expires on November 30, 2021. In June 2021, the Company entered into a new lease agreement for new office space in Dublin, Ireland, which commenced in August 2021 and has a term of one year. This new lease has an automatic renewal clause, pursuant to which the agreement will be extended automatically for successive periods equal to the current term, unless the agreement is cancelled by the Company. These operating leases are not included in the lease liability and operating lease right-of-use asset recorded due to their nominal amounts.

As of September 30, 2021, the Company is obligated to make lease payments over the remaining terms of both Dublin leases of approximately €95,000, or $110,096 as converted using an exchange rate as of September 30, 2021.

Future minimum payments under the above-described noncancelable operating leases, including a reconciliation to the lease liabilities recognized in the Condensed Consolidated Balance Sheets, and future minimum rentals to be received under the Sub-Sublease as of September 30, 2021, are as follows (in thousands):


Year Ended December 31,	Operating Leases		Sub-Sublease Rental
2021 (3 months)	1,604		752
2022	6,424		3,047
2023	6,535		3,019
2024	—		—
Total	14,563		$	6,818
Less: Present value adjustment	(700)
Nominal lease payments	(110)
Lease liability	$	13,753

Indemnity Obligations

The Company has entered into indemnification agreements with its current and former directors and officers and certain key employees. These agreements contain provisions that may require the Company, among other things, to indemnify such persons against certain liabilities that may arise because of their status or service and advance their expenses incurred as a result of any indemnifiable proceedings brought against them. The obligations of the Company pursuant to the indemnification agreements continue during such time as the indemnified person serves the Company and continues thereafter until such time as a claim can be brought. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is unlimited; however, the Company has a director and officer liability insurance policy that limits its exposure and enables the Company to recover a portion of any future amounts paid. As a result of its insurance policy coverage, the Company believes the estimated fair value of these indemnification agreements is minimal. Accordingly, the Company had no liabilities recorded for these agreements as of September 30, 2021, and 2020.

Other Commitments

In the normal course of business, the Company enters into various firm purchase commitments primarily related to research and development activities. As of September 30, 2021, the Company had non-cancelable purchase commitments to suppliers for $10.8 million of which $2.1 million is included in accrued current liabilities, and contractual obligations under license agreements of $0.5 million of which $0.1 million is included in accrued current liabilities. The following is a summary of the Company's non-cancelable purchase commitments and contractual obligations as of September 30, 2021 (in thousands):


	Total		2021		2022		2023		2024		2025		Thereafter
Purchase Obligations (1)	$	10,823	$	10,823	$	—	$	—	$	—	$	—	$	—
Contractual obligations under license agreements	490		110		55		55		45		45		180
Total	$	11,313	$	10,933	$	55	$	55	$	45	$	45	$	180

________________

(1) Purchase obligations consist of non-cancelable purchase commitments to suppliers and contract research organizations.

7. Significant Agreements

Roche License Agreement

In December 2013, the Company through its wholly owned subsidiary Prothena Biosciences Limited and Prothena Biosciences Inc entered into a License, Development, and Commercialization Agreement (the “License Agreement”) with F. Hoffmann-La Roche Ltd. and Hoffmann-La Roche Inc. (together, “Roche”) to develop and commercialize certain antibodies that target α-synuclein, including prasinezumab, which are referred to collectively as “Licensed Products.” Upon the effectiveness of the License Agreement in January 2014, the Company granted to Roche an exclusive, worldwide license to develop, make, have made, use, sell, offer to sell, import and export the Licensed Products. The Company retained certain rights to conduct development of the Licensed Products and an option to co-promote prasinezumab in the U.S. During the term of the License Agreement, the Company and Roche will work exclusively with each other to research and develop antibody products targeting alpha-synuclein (or α-synuclein) potentially including incorporation of Roche’s proprietary Brain Shuttle™ technology to potentially increase delivery of therapeutic antibodies to the brain. The License Agreement provided for Roche making an upfront payment to the Company of $30.0 million, which was received in February 2014; making a clinical milestone payment of $15.0 million upon initiation of the Phase 1 study for prasinezumab, which was received in May 2014; making a clinical milestone payment of $30.0 million upon dosing of the first patient in the Phase 2 study for prasinezumab, which was achieved in June 2017; and making a clinical milestone payment of $60.0 million upon dosing of the first patient in the global Phase 2b PADOVA study for prasinezumab, which was achieved in May 2021.

Roche bore 100% of the cost of conducting the research collaboration under the License Agreement during the research term, which expired December 31, 2017. In May 2021, the Company exercised its rights under the terms of License Agreement to receive potential U.S. commercial sales milestone and royalties, in lieu of a U.S. profit and loss share for prasinezumab in Parkinson’s disease. Thus in the U.S., through May 28, 2021, the parties shared all development costs, all of which were allocated 70% to Roche and 30% to the Company, for prasinezumab in the Parkinson’s disease indication. If the Company opts in to participate in co-development and co-funding for any other Licensed Products and/or indications, the parties will share all development and commercialization costs, as well as profits, all of which will be allocated 70% to Roche and 30% to the Company.

For prasinezumab, Roche is obligated to pay:

•up to $290.0 million upon the achievement of development, regulatory and various first commercial sales milestones;

•up to $155.0 million upon achievement of U.S. commercial sales milestones;

•up to $175.0 million upon achievement of ex-U.S. commercial sales milestones; and

•tiered, high single-digit to high double-digit royalties in the teens based on U.S. and ex-U.S. annual net sales, subject to certain adjustments, with respect to the applicable Licensed Product.

The Company filed an Investigational New Drug Application (“IND”) with the FDA for prasinezumab and subsequently initiated a Phase 1 study in 2014. Following the Phase 1 studies, Roche became primarily responsible for developing, obtaining and maintaining regulatory approval for and commercializing Licensed Products. Roche also became responsible for the clinical and commercial manufacture and supply of Licensed Products.

In addition, the Company has an option under the License Agreement to co-promote prasinezumab in the U.S. in the Parkinson’s disease indication. If the Company exercises such option, it may also elect to co-promote additional Licensed Products in the U.S. approved for Parkinson’s disease. Outside the U.S., Roche will have responsibility for developing and commercializing the Licensed Products. Roche bears all costs that are specifically related to obtaining or maintaining regulatory approval outside the U.S. and will pay the Company a variable royalty based on annual net sales of the Licensed Products outside the U.S.

The License Agreement continues on a country-by-country basis until the expiration of all payment obligations under the License Agreement. The License Agreement may also be terminated (i) by Roche at will after the first anniversary of the effective date of the License Agreement, either in its entirety or on a Licensed Product-by-Licensed Product basis, upon 90 days’ prior written notice to the Company prior to first commercial sale and 180 days’ prior written notice to Prothena after first commercial sale, (ii) by either party, either in its entirety or on a Licensed Product-by-Licensed Product or region-by-region basis, upon written notice in connection with a material breach uncured 90 days after initial written notice, and (iii) by either party, in its entirety, upon insolvency of the other party. The License Agreement may be terminated by either party on a patent-by-patent and country-by-country basis if the other party challenges a given patent in a given country. The Company’s rights to co-develop Licensed Products under the License Agreement will terminate if the Company commences certain studies for

certain types of competitive products. The Company’s rights to co-promote Licensed Products under the License Agreement will terminate if the Company commences a Phase 3 study for such competitive products.

The License Agreement cannot be assigned by either party without the prior written consent of the other party, except to an affiliate of such party or in the event of a merger or acquisition of such party, subject to certain conditions. The License Agreement also includes customary provisions regarding, among other things, confidentiality, intellectual property ownership, patent prosecution, enforcement and defense, representations and warranties, indemnification, insurance, and arbitration and dispute resolution.

Collaboration Accounting

The License Agreement was evaluated under ASC 808, Collaborative Agreements. At the outset of the License Agreement, the Company concluded that it did not qualify as collaboration under ASC 808 because the Company does not share significant risks due to the net profit and loss split (under which Roche incurs substantially more of the costs of the collaboration) and because of the Company’s opt-out provision. The Company believes that Roche will be the principal in future sales transactions with third parties as Roche will be the primary obligor bearing inventory and credit risk. The Company will record its share of pre-tax commercial profit generated from the collaboration as collaboration revenue once the Company can conclude it is probable that a significant revenue reversal will not occur in future periods. Prior to commercialization of a Licensed Product, the Company’s portion of the expenses related to the License Agreement reflected on its income statement will be limited to R&D expenses. After commercialization, if the Company opts in to co-detail commercialization, expenses related to commercial capabilities, including expenses related to the establishment of a field sales force and other activities to support the Company’s commercialization efforts, will be recorded as sales, general and administrative (“SG&A”) expense and will be factored into the computation of the profit and loss share. The Company will record the receivable related to commercialization activities as collaboration revenue once the Company can conclude it is probable that a significant revenue reversal will not occur in future periods.

Performance Obligations

The License Agreement was evaluated under ASC 606. The License Agreement includes the following distinct performance obligations: (1) the Company’s grant of an exclusive royalty bearing license, with the right to sublicense to develop and commercialize certain antibodies that target α-synuclein, including prasinezumab, and the initial know how transfer which was delivered at the effective date (the “Royalty Bearing License”); (2) the Company’s obligation to supply clinical material as requested by Roche for a period up to twelve months (the “Clinical Product Supply Obligation”); (3) the Company’s obligation to provide manufacturing related services to Roche for a period up to twelve months (the “Supply Services Obligation”); (4) the Company’s obligation to prepare and file the IND (the “IND Obligation”); and (5) the Company’s obligation to provide development activities under the development plan during Phase 1 clinical trials (the “Development Services Obligation”). Revenue allocated to the above performance obligations under the License Agreement are recognized when the Company has satisfied its obligations either at a point in time or over a period of time.

The Company concluded that the Royalty Bearing License and the Clinical Product Supply Obligation were satisfied at a point in time. The Royalty Bearing License is considered to be a functional intellectual property, in which the revenue would be recognized at the point in time since (a) the Company concluded that the license to Roche has a significant stand-alone functionality, (b) the Company does not expect the functionality of the intellectual property to be substantially changed during the license period as a result of activities of Prothena, and (c) Prothena’s activities transfer a good or service to Roche. The Clinical Product Supply Obligation does not meet criteria for over time recognition; as such, the revenue related to such performance obligation was recognized the point in time at which Roche obtained control of manufactured supplies, which occurred during the first quarter of 2014.

The Company concluded that the Supply Services Obligation, the IND Obligation and the Development Services Obligation were satisfied over time. The Company utilized an input method measure of progress by basing the recognition period on the efforts or inputs towards satisfying the performance obligation (i.e. costs incurred and the time elapsed to complete the related performance obligations). The Company determined that such input method provides an appropriate measure of progress toward complete satisfaction of such performance obligations.

As of September 30, 2021, and December 31, 2020, there were no remaining performance obligations under License Agreement since the obligations related to research and development activities were only for the Phase 1 clinical trial and the remaining obligations were delivered or performed.

Transaction Price

According to ASC 606-10-32-2, the transaction price is the amount of consideration to which an entity expects to be entitled in exchange for transferring promised goods or services to a customer, excluding amounts collected on behalf of third parties (for example, some sales taxes). The consideration promised in a contract with a customer may include fixed amounts, variable amounts, or both. Factors considered in the determination of the transaction price include, among other things, estimated selling price of the license and costs for clinical supply and development costs.

The initial transaction price under the License Agreement, pursuant to ASC 606, was $55.1 million, including $45.0 million for the Royalty Bearing License, $9.1 million for the IND and Development Services Obligations, and $1.1 million for the Supply Services Obligation. The $45.0 million for the Royalty Bearing License included the upfront payment of $30.0 million and the clinical milestone payment of $15.0 million upon initiation of the Phase 1 clinical trial of prasinezumab, both of which were made in 2014. The remaining transaction price amounts the Company expected to receive as reimbursements were based on costs expected to be paid to third parties and other costs to be incurred by the Company in order to satisfy its performance obligations. They are considered to be variable considerations not subject to constraint. The Company did not incur any incremental costs, such as commissions, to obtain or fulfill the License Agreement.

Under ASC 606, the transaction price was allocated to the performance obligations as follows: $48.9 million to the Royalty Bearing License; $4.6 million to the IND and Development Services Obligations; $1.1 million to the Clinical Product Supply Obligation; and $0.6 million to the Supply Services Obligation. As of September 30, 2021, the aggregate amount of the transaction price allocated to the performance obligations that are unsatisfied is nil. Prior to the adoption of ASC 606, the transaction price was allocated to the deliverables as follows: $35.6 million to the Royalty Bearing License; $3.3 million to the IND and Development Services Obligations; $0.8 million to the Clinical Product Supply Obligation; and $0.4 million to the Supply Services Obligation.

The Company allocated the initial transaction price to the Royalty Bearing License and other performance obligations using the relative selling price method based on its best estimate of selling price for the Royalty Bearing License and third party evidence for the remaining performance obligations. The best estimate of selling price for the Royalty Bearing License was based on a discounted cash flow model. The key assumptions used in the discounted cash flow model used to determine the best estimate of selling price for the Royalty Bearing License included the market opportunity for commercialization of prasinezumab in the U.S. and the royalty territory (for licensed products that are jointly funded the royalty territory is worldwide except for the U.S., and for all licensed products that are not jointly funded the Royalty Territory is worldwide), the probability of successfully developing and commercializing prasinezumab, the estimated remaining development costs for prasinezumab, and the estimated time to commercialization of prasinezumab. The Company concluded that a change in the assumptions used to determine the best estimate of selling price (“BESP”) of the license deliverable would not have a significant effect on the allocation of arrangement consideration.

The Company’s discounted cash flow model included several market conditions and entity-specific inputs, including the likelihood that clinical trials for prasinezumab will be successful, the likelihood that regulatory approval will be obtained and the product commercialized, the appropriate discount rate, the market locations, size and potential market share of the product, the expected life of the product, and the competitive environment for the product. The market assumptions were generated using a patient-based forecasting approach, with key epidemiological, market penetration, dosing, compliance, length of treatment and pricing assumptions derived from primary and secondary market research, referenced from third-party sources.

Significant Payment Terms

Payments for development services are due within 45 days after receiving an invoice from the Company. Variable considerations related to clinical and regulatory milestone payments are constrained due to high likelihood of a revenue reversal. The payment term for all milestone payments are due within 45 days after the achievement of the relevant milestone and receipt by Roche of an invoice for such an amount from the Company.

According to ASC 606-10-32-17, a significant financing component does not exist if a substantial amount of the consideration promised by the customer is variable, and the amount or timing of that consideration varies on the basis of the occurrence or nonoccurrence of a future event that is not substantially within the control of the customer or the entity. Since a “substantial amount of the consideration” promised by Roche to the Company is variable (i.e., is in the form of either milestone payments or sales-based royalties) and the amount of such variable consideration varies based upon the occurrence or nonoccurrence of future events that are not within the control of either Roche or the Company (i.e., are largely subject to regulatory approval), the License Agreement does not have a significant financing component.

Optional Goods and Services

An option for additional goods or services exists when a customer has a present contractual right that allows it to choose the amount of additional distinct goods or services that are purchased. Prior to the customer’s exercise of that right, the vendor is not presently obligated to provide those goods or services. ASC 606-10-25-18(j) requires recognition of an option as a distinct performance obligation when the option provides a customer with a material right.

In addition to the distinct performance obligations noted above, the Company was obligated to provide indeterminate research services for up to three years ending in 2017 at rates that were not significantly discounted and fully reimbursable by Roche (the “Research Services”). The amount for any such Research Services was not fixed and determinable and was not at a significant incremental discount. There were no refund rights, concessions or performance bonuses to consider.

The Company evaluated the obligation to perform Research Services under ASC 606-10-55-42 and 55-43 to determine whether it gave Roche a “material right”. According to ASC 606-10-55-43, if a customer has the option to acquire an additional good or services at a price that would reflect the standalone selling price for that good or service, that option does not provide the customer with a material right even if the option can be exercised only by entering into a previous contract.

The Company concluded that Roche’s option to have the Company perform Research Services did not represent a “material right” to Roche that it would not have received without entering into the License Agreement. As a result, Roche’s option to acquire additional Research Services was not considered a performance obligation at the outset of the License Agreement under ASC 606. Accordingly, this deliverable will become new performance obligation for Prothena when Roche asks Prothena to conduct such Research Services. As of September 30, 2021, and December 31, 2020, there were no remaining Research Services performance obligations.

Post Contract Deliverables

Any development services provided by the Company after performance of the Development Service Obligation are not considered a contractual performance obligation under the License Agreement, since the License Agreement does not require the Company to provide any development services after completion of the Development Service Obligation. However, the collaboration’s Joint Steering Committee approved continued funding for additional development services to be provided by the Company (the “Additional Development Services”). Under the License Agreement the Company recognizes the reimbursements for Additional Development Services as collaboration revenue as earned.

Revenue and Expense Recognition

The Company recognized nil and $60.2 million as collaboration revenue from Roche for the three and nine months ended September 30, 2021, respectively, as compared to $0.2 million and $0.4 million for the three and nine months ended September 30, 2020, respectively. For the nine months ended September 30, 2021 collaboration revenue from Roche included a $60.0 million clinical milestone recognized upon first patient dosed in the PADOVA study. Through May 28, 2021, cost sharing payments to Roche were recorded as R&D expenses. The Company recognized nil and $7.2 million in R&D expenses for payments made to Roche during the three and nine months ended September 30, 2021 respectively, as compared to $3.8 million and $12.3 million for the three and nine months ended September 30, 2020, respectively. The Company had accounts receivable from Roche of nil and $3,000 at September 30, 2021 and December 31, 2020, respectively.

Milestone Accounting

Under the License Agreement, only if the U.S. and or global options are exercised, the Company is eligible to receive milestone payments upon the achievement of development, regulatory and various first commercial sales milestones. Milestone payments are evaluated under ASC Topic 606. Factors considered in this determination included scientific and regulatory risk that must be overcome to achieve each milestone, the level of effort and investment required to achieve the milestone, and the monetary value attributed to the milestone. Accordingly, the Company estimates payments in the transaction price based on the most likely approach, which considers the single most likely amount in a range of possible amounts related to the achievement of these milestones. Additionally, milestone payments are included in the transaction price only when the Company can conclude it is probable that a significant revenue reversal will not occur in future periods when the milestone is achieved.

The Company excludes the milestone payments and royalties in the initial transaction price calculation because such payments are considered to be variable considerations with constraint. Such milestone payments and royalties will be recognized as revenue once the Company can conclude it is probable that a significant revenue reversal will not occur in future periods.

The clinical and regulatory milestones under the License Agreement after the point at which the Company could opt out are considered to be variable considerations with constraint due to the fact that active participation in the development activities that generate the milestones is not required under the License Agreement, and the Company can opt out of these activities. There are no refunds or claw-back provisions and the milestones are uncertain of occurrence even after the Company has opted out. Based on this determination, these milestones will be recognized when the Company can conclude it is probable that a significant revenue reversal will not occur in future periods.

Collaboration Agreement with Bristol Myers Squibb

Overview

On March 20, 2018, the Company, through its wholly owned subsidiary Prothena Biosciences Limited (“PBL”), entered into a Master Collaboration Agreement (the “Collaboration Agreement”) with Celgene Switzerland LLC (“Celgene”), a subsidiary of Celgene Corporation (which was acquired by Bristol Myers Squibb (“BMS”) in November 2019), pursuant to which Prothena granted to Celgene a right to elect in its sole discretion to exclusively license rights both in the U.S. (the “US Rights”) and on a global basis (the “Global Rights”), with respect to the Company’s programs to develop and commercialize antibodies targeting Tau, TDP-43 and an undisclosed target (the “Collaboration Targets”). For each such program, BMS may exercise its US Rights at the IND filing, and if it so exercises such US Rights would also have a right to expand the license to Global Rights. If BMS exercises its US Rights for a program, then following the first to occur of (a) completion by the Company, in its discretion and at its cost, of Phase 1 clinical trials for such program or (b) the date on which BMS elects to assume responsibility for completing such Phase 1 clinical trials (at its cost), BMS would have decision making authority over development activities and all regulatory, manufacturing and commercialization activities in the U.S. As discussed below, BMS exercised its US Rights for the Tau/PRX005 Collaboration Target and on July 30, 2021, PBL entered into a U.S. License Agreement granting BMS the exclusive license to develop, manufacture and commercialize antibody products in the United States targeting Tau (the “Tau US License Agreement”).

The Collaboration Agreement provided for Celgene making an upfront payment to the Company of $100.0 million which was received in April 2018, plus future potential license exercise payments and regulatory and commercial milestones for each program under the Collaboration Agreement, as well as royalties on net sales of any resulting marketed products. In connection with the Collaboration Agreement, the Company and Celgene entered into a Share Subscription Agreement on March 20, 2018, under which Celgene subscribed to 1,174,536 of the Company’s ordinary shares for a price of $42.57 per share, for a total of approximately $50.0 million.

BMS US and Global Rights and Licenses

On a program-by-program basis, beginning on the effective date of the Collaboration Agreement and ending on the date that the IND Option term expires for such program (which generally occurs sixty days after the date on which the Company delivers to BMS the first complete data package for an IND that was filed for a lead candidate from the relevant program), BMS may elect in its sole discretion to exercise its US Rights to receive an exclusive license to develop, manufacture and commercialize antibodies targeting the applicable Collaboration Target in the U.S. (the “US License”). If BMS exercises its US Rights for a collaboration program, it is obligated to pay the Company an exercise fee of approximately $80.0 million per program. Thereafter, following the first to occur of (a) completion by the Company, in its discretion and at its cost, of Phase 1 clinical trials for such program or (b) BMS’s election to assume responsibility to complete such Phase 1 clinical trials (at its cost), BMS would have the sole right to develop, manufacture and commercialize antibody products targeting the relevant Collaboration Target for such program (the “Collaboration Products”) in the U.S.

On a program-by-program basis, following completion of a Phase 1 clinical trial for a collaboration program for which BMS has previously exercised its US Rights, BMS may elect in its sole discretion to exercise its Global Rights with respect to such collaboration program to receive a worldwide, exclusive license to develop, manufacture and commercialize antibodies targeting the applicable Collaboration Target (the “Global License”). If BMS exercises its Global Rights, BMS would be obligated to pay the Company an additional exercise fee of $55.0 million for such collaboration program. The Global Rights would then replace the US Rights for that collaboration program, and BMS would have decision making authority over developing, obtaining and maintaining regulatory approval for, manufacturing and commercializing the Collaboration Products worldwide.

After BMS’s exercise of Global Rights for a collaboration program, the Company is eligible to receive up to $562.5 million in regulatory and commercial milestones per program. Following an exercise by BMS of either US Rights or Global Rights for such collaboration program, the Company will also be eligible to receive tiered royalties on net sales of Collaboration Products ranging from high single digit to high teen percentages, on a weighted average basis depending on the achievement of certain net sales thresholds. Such exercise fees, milestones and royalty payments are subject to certain reductions as specified in the Collaboration Agreement, the agreement for US Rights and the agreement for Global Rights.

BMS will continue to pay royalties on a Collaboration Product-by-Collaboration Product and country-by-country basis, until the latest of (i) expiration of certain patents covering the Collaboration Product, (ii) expiration of all regulatory exclusivity for the Collaboration Product, and (iii) an agreed period of time after the first commercial sale of the Collaboration Product in the applicable country (the “Royalty Term”).

Term and Termination

The research term under the Collaboration Agreement continues for a period of six years, which BMS may extend for up to two additional 12-month periods by paying an extension fee of $10.0 million per extension period. The term of the Collaboration Agreement continues until the last to occur of the following: (i) expiration of the research term; (ii) expiration of all US Rights terms; and (iii) expiration of all Global Rights terms.

The term of any US License or Global License would continue on a Licensed Product-by-Licensed Product and country-by-country basis until the expiration of all Royalty Terms under such agreement.

The Collaboration Agreement may be terminated (i) by either party on a program-by-program basis if the other party remains in material breach of the Collaboration Agreement following a cure period to remedy the material breach, (ii) by BMS at will on a program-by-program basis or in its entirety, (iii) by either party, in its entirety, upon insolvency of the other party, or (iv) by the Company, in its entirety, if BMS challenges a patent licensed by the Company to BMS under the Collaboration Agreement.

Share Subscription Agreement

Pursuant to the terms of the Collaboration Agreement, the Company entered into a Share Subscription Agreement (the “SSA”) with Celgene, pursuant to which the Company issued, and Celgene subscribed for, 1,174,536 of the Company’s ordinary shares (the “Shares”) for an aggregate subscription price of approximately $50.0 million, pursuant to the terms and conditions thereof.

Under the SSA, BMS (formerly Celgene) is subject to certain transfer restrictions. In addition, BMS will be entitled to request the registration of the Shares with the U.S. Securities and Exchange Commission on Form S-3ASR or Form S-3 following termination of the transfer restrictions if the Shares cannot be resold without restriction pursuant to Rule 144 promulgated under the U.S. Securities Act of 1933, as amended.

Collaboration Accounting

The Collaboration Agreement was evaluated under ASC 808, Collaborative Agreements. At the outset of the Collaboration Agreement, the Company concluded that it does not qualify as collaboration under ASC 808 because the Company does not share significant risks due to economics of the collaboration.

Performance Obligations

The Company assessed the Collaboration Agreement and concluded that it represented a contract with a customer within the scope of ASC 606. Per ASC 606, a performance obligation is defined as a promise to transfer a good or service or a series of distinct goods or services. At inception of the Collaboration Agreement, the Company is not obligated to transfer the US License or Global License to BMS unless BMS exercises its US Rights or Global Rights, respectively, and the Company is not obligated to perform development activities under the development plan during preclinical and Phase 1 clinical trials including the regulatory filing of the IND.

The discovery, preclinical and clinical development activities performed by the Company are to be performed at the Company’s discretion and are not promised goods or services and therefore are not considered performance obligations under ASC 606, unless and until the Company agrees to perform the Phase 1 clinical studies (after the IND option exercise) that are determined to be performance obligations at the time the option is exercised. Per the terms of the Collaboration Agreement, the Company may conduct discovery activities to characterize, identify and generate antibodies to become collaboration candidates that target such Collaboration Target, and thereafter may pre-clinically develop collaboration candidates to identify lead candidates that target such Collaboration Target and file an IND with the U.S. Food and Drug Administration (the “FDA”) for a Phase 1 clinical trial for such lead candidates. In the event the Company agrees to be involved in a Phase 1 clinical study, the Company will further evaluate whether any such promise represents a performance obligation at the time the option is exercised. If it is concluded that the Company has obligated itself to an additional performance obligation besides the license granted at IND option exercise, then the effects of the changes in the arrangement will be evaluated under the modification guidance of ASC 606.

The Company is not obligated to perform manufacturing activities. Per the terms of the Collaboration Agreement, to the extent that the Company, at its discretion, conducts a program, the Company shall be responsible for the manufacture of collaboration candidates and collaboration products for use in such program, as well as the associated costs. Delivery of manufactured compound (clinical product supply) is not deemed a performance obligation under ASC 606 as the Company is not obligated to transfer supply of collaboration product to BMS unless BMS exercises its right to participate in the Phase 1 development.

Compensation for the Company’s provision of inventory supply, to the extent requested by BMS would be paid to the Company by BMS at a reasonable stand-alone selling price for such supply. Given that (i) there is substantial uncertainty about the development of the programs, (ii) the pricing for the inventory is at its standalone selling price and (iii) the manufacturing services require the entity to transfer additional goods or services that are incremental to the goods and services provided prior to the resolution of the contingency, the Company’s supply of product is not a material right. Therefore, the inventory supply is not considered a performance obligation unless and until, requested by BMS.

In addition to the grant of the US License after BMS exercises its US Rights for a program, BMS is entitled to receive certain ancillary development services from the Company, such as technology transfer assistance, regulatory support, safety data reporting activities and transition supply, if requested by BMS.

In addition to the grant of the Global License after BMS exercises the Global Rights for a program, BMS is entitled to receive certain ancillary development services from the Company, such as ongoing clinical trial support upon request by BMS, transition supply, if requested by BMS, and regulatory support for coordination of pharmacovigilance matters.

The Company evaluated the potential obligations to transfer the US Licenses and Global Licenses and performance of the ancillary development services subsequent to exercise of the US Rights and Global Rights, if the options are exercised by BMS, under ASC 606-10-55-42 and 55-43 to determine whether the US Rights or the Global Rights provided BMS a “material right” and concluded that BMS’s options to exercise its US Rights and Global Rights represented “material rights” to BMS that it would not have received without entering into the Agreement.

There are a total of six options including US Rights and Global Rights to acquire a US License and a Global License, respectively, and rights to request certain development services (following exercise of the US Rights and Global Rights, respectively) for each of the three programs. Per ASC 606, the US Rights and Global Rights are material rights and therefore are performance obligations. The goods and services underlying the options are not accounted for as separate performance obligations, but rather become performance obligations, if and when, an option is exercised.

US License Agreement for the Tau/PRX005 Collaboration Target

On July 30, 2021, the Company entered into the Tau US License Agreement. The Tau US License Agreement includes an upfront payment of $80.0 million and the Company will be eligible to receive regulatory and sales milestones up to $465.0 million upon achievement of certain developmental events, including regulatory approval, of a Tau Collaboration Product, and on BMS achieving certain annual net sales thresholds in the United States. The Company also will be eligible to receive tiered royalties on net sales of Tau Collaboration Products, ranging from high single digit to high teen percentages, on a weighted average basis depending on the achieving of certain net sales thresholds. Such exercise fees, milestones and royalty payments are subject to certain reductions as specified in the agreement.

The Tau US License Agreement includes the following distinct performance obligations: (1) the delivery of the US License for Tau/PRX005 Collaboration Target (“Tau US License Obligation”); and (2) the Company’s obligation to provide development activities under the development plan during Phase 1 clinical trials (the “Tau US Development Services Obligation”). Revenue allocated to the Tau US License Obligation is recognized when the Company has satisfied its obligation at a point in time, while the revenue allocated to the Tau US Development Services Obligation are recognized when the Company has satisfied its obligations ratably over the service period.

Transaction Price

According to ASC 606-10-32-2, the transaction price is the amount of consideration to which an entity expects to be entitled in exchange for transferring promised goods or services to a customer, excluding amounts collected on behalf of third parties (for example, some sales taxes). The consideration promised in a contract with a customer may include fixed amounts, variable amounts, or both. Factors considered in the determination of the transaction price included, among other things, estimated selling price of the license and costs for clinical supply and development costs.

At the inception of the Collaboration Agreement, the Company did not transfer any goods or services to BMS (formerly Celgene) that are material. Accordingly, the Company has concluded that the initial transaction price will be recognized as contract liability and will be deferred until the Company transfers control of goods or services to BMS (which would be when BMS exercises the US Right or Global Right and receives control of the US License or Global License for at least one of the programs), or when the IND Option term expires if BMS does not exercise the US Right (which is generally sixty days after the date on which the Company delivers to BMS the first complete data package for an IND that was filed for a lead candidate from the relevant program), or when the Phase 1 Option term expires if BMS does not exercise the Global Right (which is generally ninety days after the date on which the Company delivers to BMS the first complete data package for a Phase 1 clinical trial for a lead candidate from the relevant program) or at the termination of the Collaboration Agreement, whichever occurs first. At such point that the Company transfers control of goods or services to BMS, or when the option expires, the Company will recognize revenue as a continuation of the original contract. Under this approach, the Company will treat the consideration allocated to the material right as an addition to the consideration for the goods or services underlying the contract option.

At inception of the Collaboration Agreement, the Company estimated the standalone selling price for each performance obligation (i.e., the US Rights and Global Rights by program). The estimate of standalone selling price for the US Rights and Global Rights by program was based on the adjusted market assessment approach using a discounted cash flow model. The key assumptions used in the discounted cash flow model included the market opportunity for commercialization of each program in the U.S. or globally depending on the license, the probability of successfully developing and commercializing a given program target, the estimated remaining development costs for the respective program, the estimated time to commercialization of the drug for that program and a discount rate.

The initial transaction price under the Collaboration Agreement, pursuant to ASC 606, was $110.2 million, including the $100.0 million upfront payment and $10.2 million premium on the ordinary shares purchased under the SSA. The Company expects that the initial transaction price will be allocated across the US Rights and Global Rights for each program in a range of approximately $15-$25 million and $10-$18 million, respectively.

The Company did not include the option fees in the initial transaction price because such fees are contingent on the options to the US Rights and the Global Rights being exercised. Upon the exercise of the US Rights and the Global Rights for a program, the Company will have the obligation to deliver the US License and Global License and provide certain ancillary development services if requested by BMS, subsequent to its exercise of the US Rights and Global Rights, respectively, for such program. The Company will include the option fees in the transaction price at the point in time a material right is exercised and the Company transfers control of the goods and services to BMS. In addition, the Company did not include in the initial transaction price certain clinical and regulatory milestone payments since they relate to licenses for which BMS has not yet exercised its option to obtain and these variable considerations are constrained due to the likelihood of a significant revenue reversal.

Upon entering into the Tau US License Agreement, the Company granted BMS a US License for the Tau/PRX005 Collaboration Target, which transferred control of such underlying US License to BMS. Following execution of the Tau US License Agreement, BMS paid the Company an $80.0 million option exercise fee. Under the continuation of the original contract method, the Company computed the relative sales price after the Company transferred control of the US License for Tau/PRX005. The Company used the original allocated consideration for the US Right for Tau/PRX005 of $24.9 million (computed at the inception of the contract) plus the $80.0 million option exercise fee to arrive at the total transaction price of approximately $104.9 million. This total transaction price was further allocated using the relative sales price method between the Tau US License Obligation and the Tau US Development Services Obligation.

The best estimate of selling price for the US License for Tau/PRX005 was based on a discounted cash flow model. The key assumptions used in the discounted cash flow model used to determine the best estimate of selling price for the license included the market opportunity for commercialization of Tau/PRX005, the probability of successfully developing/commercializing PRX005, the remaining development costs for Tau/PRX005, and the estimated time to commercialization of Tau/PRX005. Based on the relative selling price method, the amount that the Company allocated to the performance obligations is as follows: $77.5 million to the license to be recognized concurrent with the delivery of the license; and $27.5 million as development services to be recognized based on percentage completion over the service period estimated to be from 2021-2024.

Significant Payment Terms

The upfront payment of $100.0 million was due within ten business days after the effective date of the Collaboration Agreement and was received in April 2018, while all option fees and milestone payments are due within 30 days after the achievement of the relevant milestone by BMS or receipt by BMS of an invoice for such an amount from the Company.

The Collaboration Agreement does not have a significant financing component since a substantial amount of consideration promised by BMS to the Company is variable and the amount of such variable consideration varies based upon

the occurrence or non-occurrence of future events that are not within the control of either BMS or the Company. Variable considerations related to clinical and regulatory milestone payments and option fees are constrained due to the likelihood of a significant revenue reversal.

Revenue and Expense Recognition

For the three and nine months ended September 30, 2021, collaboration revenue from BMS that was recognized based on the relative sales price method included $77.5 million in US License revenue and $1.0 million for US development services, for a total of $78.5 million in collaboration revenue related to the Tau/PRX005 program. No collaboration revenue related to the Tau/PRX005 program was recognized during the comparable periods in 2020. As of September 30, 2021, the aggregate amount of the transaction price allocated to the performance obligations that are unsatisfied was $26.5 million. The Company had no accounts receivable from BMS at September 30, 2021 and December 31, 2020, respectively.

Deferred Revenue

Of the original deferred revenue balance of $110.2 million at the beginning of the quarter ended September 30, 2021, $24.9 million was recognized as revenue in the quarter ended September 30, 2021 related to the US Right for the Tau/PRX005 program. Of the $80.0 million option exercise fee, $53.6 million was recognized as revenue related to the US License transferred and US Development Services performed in the third quarter and the balance was deferred to future periods and will be recognized as revenue over the remaining service period.

Milestone and Royalties Accounting

The Company is eligible to receive milestone payments of up to $90.0 million per program upon the achievement of certain specified regulatory milestones and milestone payments of up to $375.0 million per program upon the achievement of certain specified commercial sales milestones under the US License for such program. The Company is also eligible to receive milestone payments of up to $187.5 million per program upon the achievement of certain specified regulatory milestones and milestone payments of up $375.0 million per program upon the achievement of certain specified commercial sale milestones under the Global License for such program. Milestone payments are evaluated under ASC Topic 606. Factors considered in this determination included scientific and regulatory risk that must be overcome to achieve each milestone, the level of effort and investment required to achieve the milestone, and the monetary value attributed to the milestone. Accordingly, the Company estimates payments in the transaction price based on the most likely approach, which considers the single most likely amount in a range of possible amounts related to the achievement of these milestones. Additionally, milestone payments are included in the transaction price only when the Company can conclude it is probable that a significant revenue reversal will not occur in future periods.

The Company excluded the milestone payments and royalties in the initial transaction price because such payments are considered to be variable considerations with constraint. Such milestone payments and royalties will be recognized as revenue at a point in time when the Company can conclude it is probable that a significant revenue reversal will not occur in future periods.

The Company did not achieve any clinical and regulatory milestones under the Collaboration Agreement during the nine months ended September 30, 2021 and 2020.

Novo Nordisk Share Purchase Agreement

On July 8, 2021, the Company together with its wholly owned subsidiary, Prothena Biosciences Limited (“PBL”), entered into a definitive share purchase agreement with Novo Nordisk A/S and Novo Nordisk Region Europe A/S (each an unrelated party). Under the terms of such agreement, Novo Nordisk acquired PBL’s wholly-owned subsidiary, Neotope Neuroscience Limited (“NNL”) and gained full worldwide rights to the intellectual property and related rights to the Company’s ATTR amyloidosis business and pipeline. Upon consummation of the transaction, NNL ceased to be a related party of PBL. The aggregate purchase price consists of an upfront payment of $60.0 million in cash, subject to customary purchase price adjustments. In addition, the Company is eligible to receive additional development and sales milestone payments totaling up to $1.17 billion, including a $40.0 million near-term clinical milestone payment.

Should Novo Nordisk achieve certain stages of development or commercialization for products or product candidates containing PRX004 or a derivative thereof in ATTR amyloidosis, PBL is entitled to receive certain milestone payments based on specified development and commercial milestones. The development and commercialization milestone payments will be discounted if the milestone events are achieved with respect to other indications. Should Novo Nordisk achieve specified thresholds of worldwide, annual net sales of the milestone products, regardless of indication, PBL will also be entitled to

receive specified one-time net sales milestone payments. All milestone payments attributable to an achieved milestone will be paid to PBL, subject to Novo Nordisk’s offset right for indemnity claims or unpaid amounts in respect of any purchase price adjustment.

The upfront payment of $60.0 million was accounted for as revenue for the three and nine months ended September 30, 2021. In addition to the upfront payment, Novo Nordisk agreed to pay for certain out of pocket expenses under the Transition Services Agreement, which netted to $0.7 million after closing adjustments related to the sale of the ATTR amyloidosis program. The total revenue recognized for the three and nine months ended September 30, 2021, related to the transaction was $60.7 million. The Company had accounts receivable of $79,000 and nil from Novo Nordisk as of September 30, 2021 and December 31, 2020, respectively.

Contingent Consideration /Milestone Accounting

The Company is eligible to receive additional development and sales milestone payments from Novo Nordisk totaling up to $1.17 billion upon achievement of certain specified development and commercial sales milestones under the share purchase agreement, including $40.0 million near-term milestone payment.

The Company excluded the milestone payments in the initial transaction price because such payments are considered to be variable considerations with constraint. Such milestone payments will be recognized as revenue at a point in time when the Company can conclude it is probable that a significant revenue reversal will not occur in future periods.

The Company did not achieve any development and sales milestones under the share purchase agreement during the three and nine months ended September 30, 2021.

8. Shareholders' Equity

Ordinary Shares

As of September 30, 2021, the Company had 100,000,000 ordinary shares authorized for issuance with a par value of $0.01 per ordinary share and 46,533,247 ordinary shares issued and outstanding. Each ordinary share is entitled to one vote and, on a pro rata basis, to dividends when declared and the remaining assets of the Company in the event of a winding up.

Euro Deferred Shares

As of September 30, 2021, the Company had 10,000 Euro Deferred Shares authorized for issuance with a nominal value of €22 per share. No Euro Deferred Shares are outstanding at September 30, 2021. The rights and restrictions attaching to the Euro Deferred Shares rank pari passu with the ordinary shares and are treated as a single class in all respects.

March 2021 Offering

In March 2021, the Company completed an underwritten public offering of an aggregate of 4,025,000 of its ordinary shares at a public offering price of $20.75 per ordinary share. The Company received aggregate net proceeds of approximately $78.0 million, after deducting the underwriting discount and offering costs.

At-the-Market Offering

In May 2021, the Company initiated an at-the-market offering program ("ATM"), which allows the Company to sell and issue its ordinary shares from time-to-time for aggregate gross proceeds of up to $100.0 million. For the three and nine months ended September 30, 2021, the Company has sold and issued 1,328,178 and 1,640,174 ordinary shares, respectively, pursuant to the ATM. For the nine months ended September 30, 2021, total gross proceeds was approximately $100.0 million before deducting underwriting discounts, commissions, and other offering expenses payable by the Company of $3.2 million.

9. Share-Based Compensation

2018 Long Term Incentive Plan

In May 2018, the Company’s shareholders approved the 2018 Long Term Incentive Plan. In May 2020 and May 2021, the Company's shareholders approved amendments to the 2018 Long Term Incentive Plan (as amended, the “2018 LTIP”) to increase the number of ordinary shares available for issuance under that Plan by 1,500,000 and 1,800,000 ordinary shares, respectively. Under the 2018 LTIP, the number of ordinary shares authorized for issuance under the 2018 LTIP is equal to the sum of (a) 5,100,000 ordinary shares, (b) 1,177,933 ordinary shares that were available for issuance under the 2012 LTIP as of the May 15, 2018, effective date of the 2018 LTIP, and (c) any ordinary shares subject to issued and outstanding awards under

the 2012 Long Term Incentive Plan (the “2012 LTIP”) that expire, are cancelled or otherwise terminate following the effective date of the 2018 LTIP; provided, that no more than 2,500,000 ordinary shares may be issued pursuant to the exercise of ISOs. The 2018 LTIP provides for the grant of ISOs, NQSOs, SARs, restricted shares, RSUs, performance bonus awards, performance share units awards, dividend equivalents and other share or cash-based awards to eligible individuals. Options under the 2018 LTIP may be granted for periods up to ten years. All options granted to date, with the exception of options granted pursuant to the Option Exchange (as discussed below), have had a ten year life.

Amended and Restated 2012 Long Term Incentive Plan

Prior to the effective date of the 2018 LTIP, employees and consultants of the Company, its subsidiaries and affiliates, as well as members of the Company’s Board of Directors, received equity awards under the 2012 LTIP. All options under the 2012 LTIP were granted for periods of ten years.

2020 Employment Inducement Incentive Plan

On February 25, 2020, the Company's Board of Directors approved the 2020 Employment Inducement Incentive Plan. The 2020 EIIP provides for the grant of NQSOs, SARs, restricted shares, RSUs, performance bonus awards, performance share units awards, or other share or cash-based awards to eligible individuals. Options under the 2020 EIIP may be granted for periods up to ten years. All options issued to date have had a ten year life. As of December 31, 2020, the number of ordinary shares authorized for issuance under the 2020 EIIP was 710,000. During the nine months ended September 30, 2021, the 2020 EIIP was further amended to increase the ordinary shares available for issuance under that Plan by 535,000 ordinary shares in aggregate. As of September 30, 2021, the number of ordinary shares authorized for issuance under the 2020 EIIP was 1,245,000 and zero ordinary shares remained available for future awards under the 2020 EIIP, although the Company's Board of Directors reserves the right to amend the 2020 EIIP to increase the number of ordinary shares available and to make additional awards to key new hires.

Shares Available for Grant

The Company granted 176,000 and 147,000 options during the three months ended September 30, 2021 and 2020, respectively, and 3,323,477 (1,372,587 of which were replacement options granted pursuant to the Option Exchange as discussed below) and 1,865,950 options during nine months ended September 30, 2021, and 2020, respectively, in aggregate under its equity plans. The Company’s option awards generally vest over four years. As of September 30, 2021, 3,152,827 ordinary shares remained available for grant under its equity plans and options to purchase 8,649,897 ordinary shares in aggregate under the Company's equity plans were outstanding with a weighted-average exercise price of approximately $17.97 per share.

2020 Option Exchange Program

On May 19, 2020, the Company's shareholders approved a proposal to allow for a one-time option exchange program (the "Option Exchange") designed to give its employees, including our named executive officers, and non-employee directors of the Company, who are employed by or providing services to the Company through the completion of the Option Exchange, the opportunity to exchange eligible options for new replacement options with an exercise price equal to the fair market value of the Company’s ordinary shares on the date the replacement options are granted. Any new replacement options would be subject to a new initial one-year vesting period from the replacement option grant date and after such initial one-year vesting period would vest in substantially equal installments on the remaining original vesting dates of each exchanged option. Additionally, any new replacement options would have a term equal to the remaining term of the applicable exchanged option.

On November 9, 2020, the Company commenced the Option Exchange which closed on February 12, 2021. Options to purchase approximately 2.1 million ordinary shares were exchanged for options to purchase approximately 1.4 million ordinary shares with an exercise price of $22.85 per share. Options were eligible to exchange if they had an exercise price equal to or greater than $17.63 per share, were granted prior to April 23, 2018, under the 2012 LTIP, and were held by an eligible participant. No incremental share-based compensation expense was recognized for the Option Exchange.

Share-based Compensation Expense

The Company estimates the fair value of share-based compensation on the date of grant using an option-pricing model. The Company uses the Black-Scholes model to value share-based compensation, excluding RSUs, which the Company values using the fair market value of its ordinary shares on the date of grant. The Black-Scholes option-pricing model determines the fair value of share-based payment awards based on the share price on the date of grant and is affected by assumptions regarding a number of complex and subjective variables. These variables include, but are not limited to, the Company’s share price, volatility over the expected life of the awards and actual and projected employee stock option exercise behaviors. Since the

Company does not have sufficient historical employee share option exercise data, the simplified method has been used to estimate the expected life of all options. The Company uses its historical volatility for the Company’s stock to estimate expected volatility starting January 1, 2018. Although the fair value of share options granted by the Company is estimated by the Black-Scholes model, the estimated fair value may not be indicative of the fair value observed in a willing buyer and seller market transaction.

As share-based compensation expense recognized in the Condensed Consolidated Financial Statements is based on awards ultimately expected to vest, it has been reduced for estimated forfeitures. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from estimates. Forfeitures were estimated based on estimated future turnover and historical experience.

Share-based compensation expense will continue to have an adverse impact on the Company’s results of operations, although it will have no impact on its overall financial position. The amount of unearned share-based compensation currently estimated to be expensed from now through the year 2025 related to unvested share-based payment awards at September 30, 2021, is $49.3 million. The weighted-average period over which the unearned share-based compensation is expected to be recognized is 2.05 years. If there are any modifications or cancellations of the underlying unvested securities, the Company may be required to accelerate and/or increase any remaining unearned share-based compensation expense. Future share-based compensation expense and unearned share-based compensation will increase to the extent that the Company grants additional equity awards.

Share-based compensation expense recorded in these Condensed Consolidated Financial Statements for the three and nine months ended September 30, 2021, and 2020 was based on awards granted under the 2012 LTIP, the 2018 LTIP, and the 2020 EIIP. The following table summarizes share-based compensation expense for the periods presented (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Research and development	$	2,450	$	2,088	$	6,622	$	6,163
General and administrative	3,605		3,495		11,149		10,643
Total share-based compensation expense	$	6,055	$	5,583	$	17,771	$	16,806

The Company recognized tax benefits from share-based awards of $1.1 million and $1.1 million for the three months ended September 30, 2021 and 2020, and $3.4 million and $3.3 million for the nine months ended September 30, 2021, and 2020 respectively.

With the exception of options granted pursuant to the Option Exchange, the fair value of the options granted to employees and non-employee directors during the three and nine months ended September 30, 2021, and 2020 was estimated as of the grant date using the Black-Scholes option-pricing model assuming the weighted-average assumptions listed in the following table:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2021			2020			2021			2020
Expected volatility	82.8		%	79.6		%	81.6		%	81.1		%
Risk-free interest rate	0.9		%	0.3		%	1.0		%	1.0		%
Expected dividend yield	—			—		%	—		%	—		%
Expected life (in years)	6.0			6.0			6.0			6.0
Weighted average grant date fair value	$	45.53		$	8.56		$	18.60		$	8.22

The fair value of employee stock options is being amortized on a straight-line basis over the requisite service period for each award. Each of the inputs discussed above is subjective and generally requires significant management judgment to determine.

The following table summarizes the Company’s stock option activity during the nine months ended September 30, 2021:


	Options	Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)	Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2020	8,744,765	$	20.42	7.19	$	4,656
Granted (1)	3,323,477	25.19
Exercised	(946,660)	14.46
Forfeited(2)	(467,697)	23.62
Expired(3)	(2,003,988)	40.98
Outstanding at September 30, 2021	8,649,897	$	17.97	7.18	$	460,683
Vested and expected to vest at September 30, 2021	8,228,512	$	17.77	7.11	$	439,882
Vested at September 30, 2021	3,433,364	$	14.23	6.25	$	195,691

________________

(1)Includes replacement options to purchase 1,372,587 ordinary shares granted pursuant to the Option Exchange.

(2)Includes unvested options to purchase 179,959 ordinary shares that were exchanged pursuant to the Option Exchange.

(3)Includes vested options to purchase 1,934,446 ordinary shares that were exchanged pursuant to the Option Exchange.

The total intrinsic value of options exercised was approximately $14.6 million and $59,000 during the three months ended September 30, 2021, and 2020, respectively, and $28.2 million and $94,000 during the nine months ended September 30, 2021, and 2020, respectively, determined as of the date of exercise.

10. Income Taxes

The major taxing jurisdictions for the Company are Ireland and the U.S. The Company recorded an income tax (benefit) /provision of ($51,000) and $4.9 million for the three and nine months ended September 30, 2021, as compared to an income tax benefit of $215,000 and $636,000 for the three and nine months ended September 30, 2020, respectively. The provision for income taxes differs from the statutory tax rate of 12.5% applicable to Ireland primarily due to Irish net operating losses for which a tax provision benefit is not recognized, exempt Irish income, U.S. income taxed at different rates, and adjustments to deferred taxes for the deductibility of stock compensation. The income tax provision reflects the estimate of the effective tax rate expected to be applicable for the full year and the Company re-evaluates this estimate each quarter based on its forecasted tax expense for the full year. Jurisdictions with a projected loss for the year where no tax benefit can be recognized are excluded from the estimated annual effective tax rate.

On January 1, 2021, the Company adopted the Accounting Standards Update 2019-12 ("ASU 2019-12"), Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. There were no impacts from the provisions of ASU 2019-12 on the Company’s tax provision for the nine months ended September 30, 2021.

Pursuant to ASU 2016-09, the Company recorded a net tax benefit of $0.4 million and net tax shortfall of $37,000 for the three and nine months ended September 30, 2021, respectively, and a net tax shortfall of a nominal amount and $0.1 million for the three and nine months ended September 30, 2020, all of which were recorded as part of its income tax provision in the Condensed Consolidated Statements of Operations.

On January 1, 2019, the Company adopted ASC 842, and it recorded a reduction in deferred tax assets of $1.0 million as part of the $3.8 million change in the opening balance of the accumulated deficit for the cumulative effect of applying ASC 842.

Deferred income taxes reflect the net tax effect of temporary differences between the carrying amount of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. The Company's deferred tax assets (“DTA”) are composed primarily of its Irish subsidiaries' net operating loss carryforwards, state net operating loss carryforwards available to reduce future taxable income of the Company's U.S. subsidiaries, federal and California tax credit carryforwards, share-based compensation and other temporary differences. The Company maintains a valuation allowance against certain U.S. federal and state and Irish deferred tax assets. Each reporting period, the Company evaluates the need for a valuation allowance on its deferred tax assets by jurisdiction.

For the nine months ended September 30, 2021, the Company recorded a reduction in DTA of $5.1 million, primarily due to changes in the Company’s 162(m) limitations of $3.5 million as a result of the Company’s option exchange program that

closed on February 12, 2021, which was considered a material modification from a tax perspective and a $0.7 million DTA reduction related to the newly issued American Rescue Plan Act, which expanded the list of covered employees.

No provision for income tax in Ireland has been recognized on undistributed earnings of the Company’s U.S. subsidiaries as the Company considers the U.S. earnings to be indefinitely reinvested.

ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

In addition to historical information, this Quarterly Report on Form 10-Q contains forward-looking statements which may cause our actual results to differ materially from expectations, plans and anticipated results discussed in forward-looking statements. Factors that could cause our actual results to differ materially include, but are not limited to, the risks and uncertainties set forth in the “Summary of Risks Affecting Our Business” at the beginning of this Quarterly Report on Form 10-Q, Part II Item 1A “Risk Factors” of this Quarterly Report on Form 10-Q, and in our other filings with the U.S. Securities and Exchange Commission.

This discussion should be read in conjunction with the Condensed Consolidated Financial Statements and Notes presented in this Quarterly Report on Form 10-Q and the Consolidated Financial Statements and Notes contained in our Annual Report on Form 10-K filed with the SEC on February 26, 2021 (the “2020 Form 10-K”).

Overview

Prothena is a late-stage clinical company with a robust pipeline of novel investigational therapeutics built on protein dysregulation expertise with the potential to change the course of devastating rare peripheral amyloid and neurodegenerative diseases. Fueled by our deep scientific expertise built over decades of research, we are advancing a pipeline of therapeutic candidates for a number of indications and novel targets for which our ability to integrate scientific insights around neurological dysfunction and the biology of misfolded proteins can be leveraged.

Our wholly-owned programs include birtamimab for the potential treatment of AL amyloidosis, and a portfolio of programs for the potential treatment of Alzheimer’s disease including PRX012 which targets Aβ (Amyloid beta) and a novel dual Aβ-Tau vaccine. Our partnered programs include prasinezumab, in collaboration with Roche for the potential treatment of Parkinson’s disease and other related synucleinopathies, and programs that target tau (PRX005), TDP-43, and an undisclosed target in collaboration with Bristol Myers Squibb for the potential treatment of Alzheimer’s disease, amyotrophic lateral sclerosis (ALS), or other neurodegenerative diseases. We are also entitled to certain potential milestone payments pursuant to the Company’s share purchase agreement with Novo Nordisk pertaining to the investigational humanized monoclonal antibody known as PRX004, which has completed Phase 1 studies for the treatment of hereditary ATTR amyloidosis.

We were formed on September 26, 2012, under the laws of Ireland and re-registered as an Irish public limited company on October 25, 2012. Our ordinary shares began trading on The Nasdaq Global Market under the symbol “PRTA” on December 21, 2012, and currently trade on The Nasdaq Global Select Market.

Birtamimab for the Potential Treatment of AL Amyloidosis

Birtamimab is an investigational humanized antibody that targets toxic misfolded light chain that causes organ dysfunction and failure in patients with AL amyloidosis. AL amyloidosis is a rare, progressive, and fatal disease where immunoglobulin light chain proteins produced by clonal plasma cells misfold, aggregate, and deposit as amyloid in vital organs. These toxic aggregates and amyloid deposits cause progressive damage and failure of vital organs, including the heart.

Birtamimab binds to both soluble and insoluble amyloid aggregates in multiple organs and promotes the clearance of amyloid deposits via phagocytosis. This depleter mechanism of action broadly targets misfolded kappa and lambda light chain to clear deposited amyloid that causes organ dysfunction and failure in patients with AL amyloidosis. Birtamimab has been granted Fast Track Designation by the U.S. Food and Drug Administration (FDA) for the treatment of Mayo Stage IV patients with AL amyloidosis to reduce the risk of mortality and has been granted Orphan Drug Designation by both the FDA and European Medicines Agency (EMA).

It is estimated that 200,000 to 400,000 patients globally suffer from this rare disease, with approximately 60,000 to 120,000 (or 30%) of those patients being categorized as Mayo Stage IV. Patients categorized at diagnosis as Mayo Stage IV have poor outcomes with current standard-of-care that aims to reduce the production of new protein but does not directly target and clear the toxic amyloid that deposits in organs. There are currently no approved treatments for AL amyloidosis and there is

an urgent unmet medical need for therapies that improve survival in patients at risk for early mortality due to amyloid deposition.

Confirmatory Phase 3 AFFIRM-AL Study Design under SPA Agreement with FDA

Based on further analyses regarding data from the VITAL study and multiple in-depth discussions with the FDA, we announced plans on February 1, 2021, to advance birtamimab into the confirmatory Phase 3 AFFIRM-AL study in Mayo Stage IV patients with AL amyloidosis. AFFIRM-AL is a registration-enabling Phase 3 study that will be conducted with a primary endpoint of all-cause mortality at p≤0.10 under a Special Protocol Assessment (SPA) agreement with the FDA.

AFFIRM-AL is a global, multi-center, double-blind, placebo-controlled, 2:1 randomized, time-to-event study expected to enroll approximately 150 newly diagnosed, treatment naïve patients with AL amyloidosis categorized as Mayo Stage IV. It has been designed to evaluate the primary endpoint of all-cause mortality with a significance level of p≤0.10. Secondary endpoints will assess change from baseline to month 9 in quality of life as measured by SF-36v2 PCS and functional capacity as measured by 6MWT distance.

An interim analysis will be conducted when approximately 50% of the events have occurred, allowing the independent data monitoring committee to recommend either continuing the study or stopping early for overwhelming efficacy. Patients will receive 24 mg/kg of birtamimab or placebo by intravenous infusion every 28 days, with all patients receiving concurrent standard of care therapy consisting of a first line bortezomib-containing regimen.

Prasinezumab for the Potential Treatment of Parkinson’s Disease and Other Synucleinopathies

Prasinezumab is an investigational monoclonal antibody targeting alpha-synuclein designed to slow the progressive neurodegeneration associated with synuclein misfolding and/or the cell-to-cell transmission of the pathogenic, aggregated forms of synuclein in Parkinson’s disease and other synucleinopathies. Prasinezumab is the focus of a worldwide collaboration between Prothena and Roche. Parkinson’s disease is a progressive degenerative disorder of the central nervous system (CNS) that affects approximately one in 100 people over the age of 60, with incidence increasing based on an aging population. With an estimated seven to 10 million people living with Parkinson’s disease worldwide today, it is the most common neurodegenerative movement disorder and fastest growing neurological disorder. There are currently no disease-modifying treatments available that target the underlying cause of Parkinson’s disease and can slow its progression.

Phase 2b PADOVA Study

A Phase 2b study (PADOVA) to further assess the efficacy of prasinezumab in an expanded patient population is being conducted by Roche. PADOVA is a Phase 2b, randomized, double-blind, placebo-controlled, multicenter study to evaluate the efficacy and safety of prasinezumab in patients with early Parkinson’s disease who are on stable symptomatic (levodopa) medication. The study will enroll 575 patients randomized to receive either prasinezumab or placebo via intravenous infusion every 4 weeks. The primary endpoint is time to meaningful progression on motor signs of the disease, as assessed by ≥5 point increase in Movement Disorder Society – Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) Part III score from baseline.

Prasinezumab is the first anti-alpha synuclein antibody to advance into late-stage development. Prothena earned a $60 million clinical milestone payment upon first patient dosed in the PADOVA study announced in May 2021.

PRX004 for the Potential Treatment of ATTR Amyloidosis

PRX004 is an investigational antibody designed to deplete amyloid associated with disease pathology in hereditary and wild type ATTR amyloidosis without affecting the native tetrameric form of the protein. PRX004’s proposed mechanism of action is to deplete both circulating non-native TTR to prevent further deposition and deposited amyloid to improve organ function. PRX004 has been shown in preclinical studies to inhibit amyloid fibril formation, neutralize soluble aggregate forms of non-native TTR, and promote clearance of insoluble amyloid fibrils through antibody-mediated phagocytosis. This differentiated depleter mechanism of action could be developed as a monotherapy approach to ATTR amyloidosis and might also complement existing therapeutic approaches which either stabilize or reduce production of the native TTR tetramer. It is estimated that between 400,000 to 1.4 million patients suffer from ATTR-cardiomyopathy (ATTR-CM). Within this population, between 130,000 to 490,000 patients are estimated to be moderate-to-advanced and categorized as New York Heart Association Class III and IV. Prothena has completed a Phase 1 study with PRX004 in patients with hereditary forms of ATTR, in which PRX004 was found to be safe and well tolerated.

On July 12, 2021, we announced that Prothena and Novo Nordisk entered into a definitive purchase agreement under which Novo Nordisk acquired Prothena’s clinical stage antibody PRX004 and broader ATTR amyloidosis business.

Under the terms of the definitive purchase agreement, Novo Nordisk acquires Prothena’s wholly-owned subsidiary and gains full worldwide rights to the intellectual property and related rights of Prothena’s ATTR amyloidosis business and pipeline. The aggregate purchase price consists of an upfront payment of $60 million in cash, subject to customary purchase price adjustments. In addition, we are eligible to receive development and sales milestone payments totaling up to $1.17 billion, including $40 million in near-term clinical milestone payments.

PRX005 for the Potential Treatment of Alzheimer’s Disease

PRX005 is designed to be a best-in-class anti-tau antibody that specifically targets a key region within the microtubule binding region (“MTBR”), which has been shown in preclinical studies to be involved in the pathological spread of tau. Neurofibrillary tangles composed of misfolded tau proteins, along with amyloid beta plaques, are pathological hallmarks of Alzheimer’s disease. Cell-to-cell transmission of pathogenic extracellular tau and the accumulation of pathogenic tau also correlate with the progression of symptomatology and clinical decline in patients with Alzheimer’s disease. Recent publications suggest that during the course of Alzheimer’s disease progression, tau appears to spread throughout the brain via synaptically-connected pathways; this propagation of pathology is thought to be mediated by tau “seeds” containing the MTBR of tau. Additionally, it has been recently reported that the presence of MTBR fragments in cerebrospinal fluid correlate with dementia stages in Alzheimer’s disease to a higher degree than fragments of other tau regions. In preclinical research, antibodies targeting this region of tau were superior in blocking tau uptake and neurotoxicity, which has been associated with efficacy in Alzheimer’s disease animal models. In these preclinical models, PRX005 demonstrated significant inhibition of cell-to-cell transmission and neuronal internalization in vitro and in vivo and slowed pathological progression in a tau transgenic mouse model. A Phase 1 study of PRX005 has been initiated.

Global Neuroscience Research and Development Collaboration with Bristol Myers Squibb

In June 2021, we announced that Bristol Myers Squibb exercised its option under the global neuroscience research and development collaboration to enter into an exclusive U.S. license for PRX005. BMS paid Prothena $80.0 million following the execution of a US License Agreement for PRX005 and transfer of the underlying license.

This global neuroscience research and development collaboration is focused on three proteins implicated in the pathogenesis of several neurodegenerative diseases, including tau, TDP-43 and an undisclosed target. PRX005 is designed to be a best-in-class anti-tau, MTBR-specific antibody for the potential treatment of Alzheimer’s disease and is the first program to advance to the clinic from this collaboration, where the Phase 1 study has initiated. After receiving the $80 million payment described above, Prothena has received a total of $230 million pursuant to the collaboration and is eligible to receive up to an additional $160 million for U.S. rights, up to $165 million for global rights, and up to $1.7 billion for regulatory and commercial milestone payments for a total of up to $2.2 billion plus potential tiered commercial sales royalties across multiple programs.

PRX012 for the Potential Treatment of Alzheimer’s Disease

PRX012 is a high affinity monoclonal antibody targeting a key epitope within the N-terminus of Aβ. We are developing PRX012 as a next generation, high potency, anti-abeta antibody with best-in-class potential. Monoclonal antibodies targeting key epitopes within the N-terminus of Aβ have demonstrated that reducing amyloid plaque burden is associated with the slowing of clinical decline in Alzheimer’s disease. To address the growing prevalence of Alzheimer’s disease with a therapeutic that can be made widely accessible to patients, we have developed highly potent anti-Aβ antibodies that retain or improve key attributes that are thought to underlie the observed efficacy of N-terminally directed therapeutics such as aducanumab, with the aim of offering similar or improved efficacy with convenient subcutaneous dosing regimens.

Prothena antibodies demonstrated a higher binding strength to amyloid than aducanumab; specifically, antibodies with as much as an 11-fold greater affinity/avidity for fibrillar Aβ than aducanumab that also neutralized soluble, toxic (i.e., oligomeric) Aβ species. Prothena antibodies were also shown to recognize Aβ pathology to a greater extent than aducanumab, demonstrating more extensive plaque area binding at lower antibody concentrations, which are estimated to be clinically relevant exposures in the central nervous system following systemic dosing.

In July 2021, we presented a poster at the Alzheimer’s Association International Conference (AAIC) in Denver highlighting the ability of PRX012 to mediate microglial phagocytic clearance of both unmodified Aβ and pyroglutamate-modified AβpE3-42, in plaques of human Alzheimer’s brain tissue ex vivo.

Dual Aβ-Tau Vaccine for the Potential Treatment and Prevention of Alzheimer’s Disease

We are developing a dual vaccine, which concomitantly targets key epitopes within both the Aβ and tau proteins. Preclinical models suggest that Aβ and tau act synergistically in the development of Alzheimer’s disease; however, the majority of vaccines and passive immunotherapies under development today target only one of these two pathological features.

Our dual Aβ-Tau vaccine is being developed for the potential prevention and treatment of Alzheimer’s disease. In preclinical studies, the Aβ-tau vaccine has generated polyclonal responses against key epitopes within the N-terminal of Aβ and a key region of tau to promote amyloid clearance and blockade of tau transmission. Immunohistochemistry using sera from immunized animals demonstrated an appropriate and balanced immune response with antibodies that react to both Aβ plaques and tau tangles at concentrations expected to be reached in CNS following immunization and resultant titer generation.

In July 2021, we presented a poster at AAIC highlighting the generation of appropriate antibody quantities, phagocytosis of Aβ, and blockade of tau binding to heparan-sulfate analog, a surrogate endpoint for neuronal uptake of tau by various vaccine constructs.

At-the-Market Offering Program

In May 2021, the Company initiated an at-the-market offering program ("ATM"), which allows the Company to sell and issue shares of the Company's ordinary shares from time-to-time for an aggregate gross proceeds of up to $100.0 million. As of September 30, 2021, the Company has issued 1,640,174 ordinary shares pursuant to the ATM, with total gross proceeds of $100.0 million before deducting underwriting discounts, commissions, and other offering expenses payable by the Company of $3.2 million.

Critical Accounting Policies and Estimates

Management’s discussion and analysis of our financial condition and results of operations is based on our condensed consolidated financial statements, which have been prepared in accordance with the accounting principles generally accepted in the U.S. (“GAAP”). The preparation of these condensed consolidated financial statements requires us to make estimates and assumptions for the reported amounts of assets, liabilities, revenues, expenses and related disclosures.

There were no significant changes to our critical accounting policies and estimates during the nine months ended September 30, 2021, from the critical accounting policies and estimates disclosed in Management's Discussion and Analysis of Financial Condition and Results of Operations in our 2020 Form 10-K.

Recent Accounting Pronouncements

There have been no new accounting pronouncements or changes to accounting pronouncements during the nine months ended September 30, 2021, as compared to the recent accounting pronouncements described in our 2020 Form 10-K, that are of significance or potential significance to us.

Results of Operations

Comparison of Three and Nine Months Ended September 30, 2021 and 2020

Revenue


	Three Months Ended September 30,		Percentage Change
	2021	2020
	(Dollars in thousands)
Collaboration revenue	78,480	157	49,887	%
Revenue from license and intellectual property	60,694	—	n/m
Total revenue	139,174	157	88,546	%


	Nine Months Ended September 30,		Percentage Change
	2021	2020
	(Dollars in thousands)
Collaboration revenue	138,661	443	31,200	%
Revenue from license and intellectual property	60,744	50	121,388	%
Total revenue	199,405	493	40,347	%

___________

n/m = not meaningful

Total revenue was $139.2 million and $0.2 million for the three months ended September 30, 2021, and 2020, respectively, and $199.4 million and $0.5 million for the nine months ended September 30, 2021, and 2020, respectively.

Collaboration revenue includes milestone payments and reimbursements under our License Agreement with Roche. For the nine months ended September 30, 2021, collaboration revenue from Roche included a $60.0 million clinical milestone recognized upon first patient dosed in the PADOVA study. See Note 7, “Significant Agreements” to the Consolidated Financial Statements regarding the Roche License Agreement for more information.

Collaboration revenue also included revenue recognized under our Collaboration Agreement with Bristol Myers Squibb. For the three and nine months ended September 30, 2021, collaboration revenue recognized from BMS was $78.5 million of the total transaction consideration of $104.9 million for the PRX005 US License and US Development Services, see Note 7, “Significant Agreements” to the Consolidated Financial Statements regarding the Collaboration Agreement with Bristol Myers Squibb for more information.

License and intellectual property revenue included $60.7 million in revenue from the sale of intellectual property and related rights to the Company’s ATTR amyloidosis business and pipeline to Novo Nordisk in the three and nine months ended September 30, 2021 and $50,000 in license fees during the nine months ended September 20, 2021 and 2020 paid under the License Agreement entered into on March 1, 2020, between our wholly owned subsidiary, Prothena Biosciences Limited, and F. Hoffmann-La Roche Ltd. See Note 7, “Significant Agreements” to the Consolidated Financial Statements regarding the Novo Nordisk Share Purchase Agreement for more information.

Operating Expenses


	Three Months Ended September 30,		Percentage Change
	2021	2020
	(Dollars in thousands)
Research and development	17,992	21,605	(17)	%
General and administrative	11,955	9,398	27	%
Total operating expenses	29,947	31,003	(3)	%


	Nine Months Ended September 30,		Percentage Change
	2021	2020
	(Dollars in thousands)
Research and development	60,226	54,124	11	%
General and administrative	34,112	28,795	18	%
Total operating expenses	94,338	82,919	14	%

Total operating expenses consist of R&D expenses and general and administrative (“G&A”) expenses. Our operating expenses were $29.9 million and $94.3 million for the three and nine months ended September 30, 2021, respectively, and $31.0 million and $82.9 million for the three and nine months ended September 30, 2020, respectively.

Our R&D expenses primarily consist of personnel costs and related expenses, including share-based compensation and external costs associated with nonclinical activities and drug development related to our drug programs, including birtamimab (formerly NEOD001), prasinezumab, PRX004 (through July 8, 2021), PRX005 and our discovery programs. Through May 28,

2021, pursuant to our License Agreement with Roche, we made payments to Roche for our share of the development expenses incurred by Roche related to the prasinezumab program, which is included in our R&D expense. On May 28, 2021, we announced the exercise of our rights under the terms of the ongoing worldwide collaboration with Roche to receive potential U.S. commercial sales milestones and tiered royalties in lieu of a U.S. profit and loss share for prasinezumab in Parkinson’s disease.

Our G&A expenses primarily consist of professional service expenses and personnel costs and related expenses, including share-based compensation.

Research and Development Expenses

Our R&D expense decreased by $3.6 million or 17%, for the three months ended September 30, 2021, and increased by $6.1 million or 11% for the nine months ended September 30, 2021, compared to the same periods in the prior year. The decrease for the three months ended September 30, 2021, compared to the same period the prior year was primarily due to lower manufacturing costs primarily related to the PRX005 and birtamimab programs, lower collaboration expenses related to the prasinezumab program with Roche as a result of the cost share opt-out exercised in May 2021; offset in part by higher personnel related expenses and higher clinical trial expenses primarily related to the birtamimab and PRX005 programs. The increase for the nine months ended September 30, 2021, compared to the same period the prior year was primarily due to higher personnel expenses, higher clinical trial expenses primarily related to the birtamimab and PRX005 programs (offset in part by lower PRX004 clinical trial expense) and higher R&D consulting expenses; offset in part by lower collaboration expenses related to the prasinezumab program with Roche as a result of the cost share opt-out exercised in May 202l and lower manufacturing expenses primary related to the PRX005 and birtamimab programs.

Our research activities are aimed at developing new drug products. Our development activities involve the translation of our research into potential new drugs. R&D expenses include personnel costs and related expenses, external expenses associated with nonclinical and drug development and materials, equipment and facilities costs that are allocated to clearly related R&D activities.

The following table sets forth the R&D expenses for our major programs (specifically, any program with successful first dosing in a Phase 1 clinical trial, which were birtamimab, prasinezumab, PRX003, and PRX004 (through July 8, 2021)) and other R&D expenses for the three and nine months ended September 30, 2021, and 2020, and the cumulative amounts to date (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,				Cumulative to Date
	2021		2020		2021		2020		Cumulative to Date
Birtamimab (NEOD001) (1)	$	8,089	$	4,840	$	22,185	$	7,725	$	345,574
Prasinezumab (PRX002/RG7935)(2)	$	151	$	4,254	$	8,087	$	13,606	$	106,426
PRX003 (3)	$	4	$	28	$	48	$	(236)	$	59,006
PRX004 (4)	$	284	$	2,565	$	3,547	$	9,343	$	78,509
PRX005 (5)	$	3,569	$	5,148	$	8,961	$	10,210	$	29,200
Other R&D (6)	$	5,895	$	4,770	$	17,398	$	13,476
	$	17,992	$	21,605	$	60,226	$	54,124

(1)Cumulative R&D costs to date for birtamimab (NEOD001) include the costs incurred from the date when the program was separately tracked in preclinical development. Expenditures in the early discovery stage are not tracked by program and accordingly have been excluded from this cumulative amount.

(2)Cumulative R&D costs to date for prasinezumab and related antibodies include the costs incurred from the date when the program was separately tracked in nonclinical development. Expenditures in the early discovery stage are not tracked by program and accordingly have been excluded from this cumulative amount. Through May 28, 2021, Prasinezumab costs include payments to Roche for our share of the development expenses incurred by Roche related to prasinezumab programs. For the three and nine months ended September 30, 2021, nil and $0.2 million,respectively, and for the three and nine months ended September 30, 2020, $0.2 million and $0.4 million, respectively, of reimbursements from Roche for development services were recorded as part of collaboration revenue.

(3)Cumulative R&D costs to date for PRX003 include the costs incurred from the date when the program was separately tracked in nonclinical development. Expenditures in the early discovery stage are not tracked by program and accordingly have been excluded from this cumulative amount. Based on the Phase 1b multiple ascending dose study results announced in September 2017, we announced that we will not advance PRX003 into mid-stage clinical development for psoriasis or psoriatic arthritis as previously planned.

(4)Cumulative R&D costs to date for PRX004 include the costs incurred from the date when the program was separately tracked in nonclinical development. Expenditures in the early discovery stage are not tracked by program and accordingly have been excluded from this cumulative amount. On July 8, 2021, we sold shares of one of our wholly-owned subsidiaries to Novo Nordisk. In connection with the transaction, Novo Nordisk acquired our ATTR amyloidosis program, including the clinical stage antibody PRX004.

(5)Cumulative R&D costs to date for PRX005 include the costs incurred from the date when the program was separately tracked in nonclinical development. Expenditures in the early discovery stage are not tracked by program and accordingly have been excluded from this cumulative amount.

(6)Other R&D is comprised of preclinical development and discovery programs that have not progressed to first patient dosing in a Phase 1 clinical trial.

We expect our R&D expenses to increase for the full year ended December 31, 2021, over the prior year, primarily due to planned spending for our late stage program, birtamimab.

General and Administrative Expenses

Our G&A expenses increased by $2.6 million, or 27%, for the three months ended September 30, 2021, and increased by $5.3 million or 18% for the nine months ended September 30, 2021, compared to the same periods in the prior year. The increase for the three and nine months ended September 30, 2021, compared to the prior year, was primarily due to higher personnel expense, higher legal expenses, higher consulting and higher expense for our director and officer insurance premium.

We expect our G&A expenses to increase for the full year ended December 31, 2021, compared to the prior year, primarily related to higher personnel costs including share based compensation and increases in our director and officer insurance premiums.

Other Income (Expense)


	Three Months Ended September 30,				Percentage Change
	2021		2020
	(Dollars in thousands)
Interest income	$	11	$	43	(74)	%
Other income (expense), net	(42)		11		n/m
Total other income (expense), net	$	(31)	$	54	n/m


	Nine Months Ended September 30,				Percentage Change
	2021		2020
	(Dollars in thousands)
Interest income	$	30	$	1,359	(98)	%
Other income (expense), net	(80)		3		n/m
Total other income (expense), net	$	(50)	$	1,362	n/m

___________

n/m = not meaningful

Interest income decreased by $32,000, or 74%, for the three months ended September 30, 2021, and decreased by $1.3 million or 98%, for the nine months ended September 30, 2021 compared to the same periods in the prior year, primarily due to lower interest income from our cash and money market accounts resulting from lower interest rates. Other income (expense), net for the three and nine months ended September 30, 2021, and 2020, was primarily foreign exchange gains (losses) from transactions with vendors denominated in Euros.

Provision for (benefit from) Income Taxes


	Three Months Ended September 30,				Percentage Change
	2021		2020
	(Dollars in thousands)
Benefit from income taxes	$	(51)	$	(215)	(76)	%


	Nine Months Ended September 30,				Percentage Change
	2021		2020
	(Dollars in thousands)
Provision for (benefit from) income taxes	$	4,863	$	(636)	n/m

___________

n/m = not meaningful

The (benefit from) income taxes for the three months ended September 30, 2021, and 2020, was $(51,000) and $(215,000), respectively. The provision for and (benefit from) income taxes for the nine months ended September 30, 2021, and 2020, was $4.9 million and $(636,000), respectively. The benefit from income taxes decreased by $0.2 million for the three months ended September 30, 2021, compared to the same period in the prior year primarily due to the current and deferred tax impact of the exercise of stock options during the quarter. The provision for income taxes increased by $5.5 million for the nine months ended September 30, 2021, compared to the same period in the prior year was primarily due to a decrease in deferred tax asset related to our February 12, 2021 option exchange program and a change in our share-based compensation 162(m) limitations associated with the increase in the number of covered employees under the American Rescue Plan Act.

The tax provisions for all periods presented reflect U.S. federal taxes associated with recurring profits attributable to intercompany services that our U.S. subsidiary performs for the Company. No tax benefit has been recorded related to tax losses recognized in Ireland and any deferred tax assets for those losses are offset by a valuation allowance.

Liquidity and Capital Resources

Overview


	September 30,		December 31,
	2021		2020
Working capital	$	578,329	$	273,436
Cash and cash equivalents	600,098		295,380
Total assets	632,704		332,975
Total liabilities	142,233		148,969
Total shareholders’ equity	490,471		184,006

Working capital was $578.3 million as of September 30, 2021, an increase of $304.9 million from working capital of $273.4 million as of December 31, 2020. This increase in working capital during the nine months ended September 30, 2021, was primarily attributable to a higher cash and cash equivalents balance resulting from the net proceeds of $96.8 million from our ATM offering, net proceeds of approximately $78.0 million from our public offering in March 2021, option exercise fee of $80.0 million from BMS, milestone payment of $60.0 million from Roche, upfront payment of $60.0 million from Novo Nordisk, and proceeds from stock option exercises of approximately $13.7 million, partially offset by cash use of $94.3 million for operating expenses (adjusted to exclude non-cash charges).

As of September 30, 2021, we had $600.1 million in cash and cash equivalents. Although we believe, based on our current business plans, that our existing cash and cash equivalents will be sufficient to meet our obligations for at least the next twelve months, we anticipate that we will require additional capital in the future in order to continue the research and development of our drug candidates. Additionally, in order to develop and obtain regulatory approval for our potential products we will need to raise substantial additional funds. We expect to raise any such additional funds through public or private equity or debt financings, collaborative agreements with corporate partners, or other arrangements. We cannot assume that such additional financings will be available on acceptable terms, if at all, and such financings may only be available on terms dilutive to our shareholders.

In managing our liquidity needs in Ireland, we do not rely on unrepatriated earnings as a source of funds. As of September 30, 2021, $173.8 million of our outstanding cash and cash equivalents related to U.S. operations are considered permanently reinvested. We do not intend to repatriate these funds. However, if these funds were repatriated back to Ireland, we would incur a withholding tax from the dividend distribution.

The adequacy of our cash resources depends on many assumptions, including assumptions with respect to our expenses. These assumptions may prove to be wrong, and we could use our available capital resources sooner than we currently expect. Because of the numerous risks and uncertainties associated with the development and commercialization of our product

candidates, we are unable to estimate the amounts of increased capital outlays and operating expenses associated with completing the development of our product candidates. Our future capital requirements will depend on numerous factors, including, without limitation, the timing of initiation, progress, results and costs of our clinical trials; the results of our research and nonclinical studies; the costs of clinical manufacturing and of establishing commercial manufacturing arrangements; the costs of preparing, filing and prosecuting patent applications and maintaining, enforcing and defending intellectual property-related claims; the costs and timing of capital asset purchases; our ability to establish research collaborations, strategic collaborations, licensing or other arrangements; the costs to satisfy our obligations under current and potential future collaborations; the costs of any in-licensing transactions; and the timing, receipt, and amount of revenues or royalties, if any, from any approved drug candidates.

Pursuant to the License Agreement with Roche, in the U.S., through May 28, 2021, we and Roche shared all development allocated 70% to Roche and 30% to us, for prasinezumab, as well as any other Licensed Products and/or indications for which we choose to co-develop and co-fund. In May 2021, we exercised our rights under the terms of License Agreement to receive potential U.S. commercial sales milestone and royalties, in lieu of a U.S. profit and loss share for prasinezumab. This change in participation does not affect our rights and obligations outside the United States. See Note 7, “Significant Agreements” to the Consolidated Financial Statements regarding the Roche License Agreement for more information.

Our cash and cash equivalents may also be potentially supplemented in the future by proceeds from our collaboration partners and milestone payments from Novo Nordisk. Pursuant to the Collaboration Agreement with Roche, the company is eligible to receive payments for commercial and regulatory milestones and royalties on net sales of Collaboration Products. See Note 7, “Significant Agreements” to the Consolidated Financial Statements regarding the Roche License Agreement for more information. Pursuant to the Collaboration Agreement with BMS (formerly Celgene), the Company is eligible to receive payments for commercial and regulatory milestones and royalties on net sales of Collaboration Products. See Note 7, “Significant Agreements” to the Consolidated Financial Statements regarding the Collaboration Agreement with Bristol Myers Squibb for more information. Pursuant to the share purchase agreement with Novo Nordisk, the Company has received an upfront payment of $60 million in cash, subject to customary purchase price adjustments. In addition, we are eligible to receive development and sales milestone payments totaling up to $1.17 billion, including $40 million based on initiation of a Phase 2 study. The development and commercialization milestone payments will be discounted if the milestone events are achieved with respect to other indications. If Novo Nordisk achieves specified thresholds of worldwide, annual net sales of the milestone products, regardless of indication, we will be entitled to receive specified one-time net sales milestone payments. All milestone payments attributable to an achieved milestone will be paid to us, subject to Novo Nordisk’s offset right for indemnity claims or unpaid amounts in respect of any purchase price adjustment, as discussed in more detail in the share purchase agreement.

Cash Flows for the Nine Months Ended September 30, 2021 and 2020

The following table summarizes, for the periods indicated, selected items in our Condensed Consolidated Statements of Cash Flows (in thousands):


	Nine Months Ended September 30,
	2021	2020
Net cash provided by (used in) operating activities	115,063	(61,268)
Net cash used in investing activities	(256)	(145)
Net cash provided by financing activities	188,559	215
Net increase (decrease) in cash, cash equivalents and restricted cash	303,366	(61,198)

Cash Provided by (Used in) Operating Activities

Net cash provided by operating activities was $115.1 million for the nine months ended September 30, 2021, primarily from option exercise fee of $80.0 million from BMS, milestone payment of $60.0 million from Roche, and upfront payment of $60.0 million from Novo Nordisk partially offset by use of $94.3 million for operating expense (adjusted to exclude non-cash charges of approximately $28.0 million) and cash paid for prepaid expenses, other current liabilities, and operating lease payments.

Net cash used in operating activities was $61.3 million for the nine months ended September 30, 2020, primarily due to use of $82.9 million for operating expenses (adjusted to exclude non-cash charges of approximately $20.5 million)

Cash Used in Investing Activities

Net cash used in investing activities was $256,000 and $145,000 for the nine months ended September 30, 2021, and 2020, respectively. Net cash used in investing activities for the nine months ended September 30, 2021, and 2020, was primarily related to purchases of property and equipment.

Cash Provided by Financing Activities

Net cash provided by financing activities was $188.6 million for the nine months ended September 30, 2021, primarily from net proceeds from an ATM of $96.8 million, net proceeds from issuance of ordinary shares in public offering of $78.0 million, and proceeds from issuances of ordinary shares upon exercises of stock options of $13.7 million.

Net cash provided by financing activities for the nine months ended September 30, 2020, was primarily from proceeds from the issuance of ordinary shares upon exercise of stock options of $215,000.

Off-Balance Sheet Arrangements

At September 30, 2021, we were not a party to any off-balance sheet arrangements that have, or are reasonably likely to have, a current or future effect on our financial condition, changes in financial condition, revenue or expenses, results of operations, liquidity, capital expenditures or capital resources.

Contractual Obligations

Our contractual obligations as of September 30, 2021, consisted of minimum cash payments under operating leases of $14.6 million, purchase obligations of $10.8 million (of which $2.1 million is included in accrued current liabilities), and contractual obligations under license agreements of $0.5 million (of which $0.1 million is included in accrued current liabilities). Purchase obligations consist of non-cancelable purchase commitments to suppliers. Operating leases represent our future minimum rental commitments under our non-cancelable operating leases.

In March 2016, we entered into a noncancelable operating sublease to lease 128,751 square feet of office and laboratory space in South San Francisco, California. We are obligated to make lease payments totaling approximately $39.2 million over the lease term. Of this obligation, approximately $14.5 million remains outstanding as of September 30, 2021.

We have an existing office space in Dublin, Ireland which expires on November 30, 2021. In June 2021, we entered into a new lease agreement for new office space in Dublin, Ireland, which commenced in August 2021 and has a term of one year. This new lease has an automatic renewal clause, pursuant to which the agreement will be extended automatically for successive periods equal to the current term, unless cancelled by us. As of September 30, 2021, we are obligated to make lease payments over the remaining terms of both Dublin leases of approximately €95,000, or $110,096 as converted using an exchange rate as of September 30, 2021.

The following is a summary of our contractual obligations as of September 30, 2021 (in thousands):


	Total		2021		2022		2023		2024		2025		Thereafter
Operating leases (1)	$	14,563	$	1,604	$	6,424	$	6,535	$	—	$	—	$	—
Purchase obligations (2)	10,823		10,823		—		—		—		—		—
Contractual obligations under license agreements	490		110		55		55		45		45		180
Total	$	25,876	$	12,537	$	6,479	$	6,590	$	45	$	45	$	180

(1) See Note 6, “Commitments and Contingencies” to our Condensed Consolidated Financial Statements.

(2) Purchase obligations consist of non-cancelable purchase commitments to suppliers and contract research organizations.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Foreign Currency Risk

Our business is primarily conducted in U.S. dollars except for our agreements with contract manufacturers for drug supplies which are denominated in Euros. For the nine months ended September 30, 2021, we recorded a loss on foreign currency exchange rate differences of approximately $80,000 and for the nine months ended September 30, 2020, we recorded

a gain on foreign currency exchange rate differences of approximately $3,000, respectively. If we increase our business activities that require the use of foreign currencies, we may be exposed to losses if the Euro and other such currencies continue to strengthen against the U.S. dollar.

Interest Rate Risk

Our exposure to interest rate risk is limited to our cash equivalents, which consist of accounts maintained in money market funds. We have assessed that there is no material exposure to interest rate risk given the nature of money market funds. In general, money market funds are not subject to interest rate risk because the interest paid on such funds fluctuates with the prevailing interest rate. Accordingly, our interest income fluctuates with short-term market conditions.

In the future, we anticipate that our exposure to interest rate risk will primarily be related to our investment portfolio. We intend to invest any surplus funds in accordance with a policy approved by our board of directors which will specify the categories, allocations, and ratings of securities we may consider for investment. The primary objectives of our investment policy are to preserve principal and maintain proper liquidity to meet our operating requirements. Our investment policy also specifies credit quality standards for our investments and limits the amount of credit exposure to any single issue, issuer or type of investment.

Credit Risk

Financial instruments that potentially subject us to concentration of credit risk consist of cash and cash equivalents and accounts receivable. We place our cash and cash equivalents with high credit quality financial institutions and pursuant to our investment policy, we limit the amount of credit exposure with any one financial institution. Deposits held with banks may exceed the amount of insurance provided on such deposits. We have not experienced any losses on our deposits of cash and cash equivalents. Our credit risk exposure is up to the extent recorded on our Condensed Consolidated Balance Sheets.

ITEM 4. CONTROLS AND PROCEDURES

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our chief executive officer (“CEO”) and chief financial officer (“CFO”) evaluated the effectiveness of our disclosure controls and procedures pursuant to Rule 13a-15 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), as of the end of the period covered by this Form 10-Q. Based on this evaluation, our CEO and CFO concluded that, as of September 30, 2021, our disclosure controls and procedures are designed and are effective to provide reasonable assurance that information we are required to disclose in reports that we file or submit under the Exchange Act is recorded, processed, summarized, and reported within the time periods specified in the SEC’s rules and forms, and that such information is accumulated and communicated to our management, including our CEO and CFO, as appropriate, to allow timely decisions regarding required disclosure.

Changes in Internal Control over Financial Reporting

There were no changes in our internal control over financial reporting identified in management’s evaluation pursuant to Rules 13a-15(d) or 15d-15(d) of the Exchange Act during our third fiscal quarter ended September 30, 2021, that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Limitations on Effectiveness of Controls and Procedures

Internal control over financial reporting has inherent limitations. Internal control over financial reporting is a process that involves human diligence and compliance and is subject to lapses in judgment and breakdowns resulting from human failures. Internal control over financial reporting also can be circumvented by collusion or improper management override. Because of such limitations, there is a risk that material misstatements will not be prevented or detected on a timely basis by internal control over financial reporting. However, these inherent limitations are known features of the financial reporting process. Therefore, it is possible to design into the process safeguards to reduce, though not eliminate, this risk.

Our management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives. In addition, the design of disclosure controls and procedures must reflect the fact that there are resource constraints and that management necessarily applies its judgment in evaluating the benefits of possible controls and procedures relative to their costs.

PART II. OTHER INFORMATION

ITEM 1. LEGAL PROCEEDINGS

We are not currently a party to any material legal proceedings. We may at times be party to ordinary routine litigation incidental to our business. When appropriate in management’s estimation, we may record reserves in our financial statements for pending legal proceedings.

ITEM 1A. RISK FACTORS

Investing in our ordinary shares involves a high degree of risk. Our Annual Report on Form 10-K for 2020 (filed with the SEC on February 26, 2021) includes a detailed discussion of our business and the risks to our business. You should carefully read that Form 10-K. You should also read and carefully consider the risks described below and the other information in this Quarterly Report on Form 10-Q. The occurrence of any of the events or developments described below could materially and adversely affect our business, financial condition, results of operations and/or growth prospects. In such an event, the market price of our ordinary shares could decline, and you may lose all or part of your investment in our ordinary shares. Additional risks and uncertainties not presently known to us or that we currently deem immaterial also may impair our business operations.

Risks Relating to Our Financial Position, Our Need for Additional Capital, and Our Business

We anticipate that we will incur losses for the foreseeable future and we may never sustain profitability.

We may not generate the cash that is necessary to finance our operations in the foreseeable future. We incurred net losses of $111.1 million, $77.7 million and $155.6 million for the years ended December 31, 2020, 2019, and 2018, respectively. We expect to continue to incur substantial losses for the foreseeable future as we:

•support the Phase 3 AFFIRM-AL clinical trial for birtamimab, the Phase 1 clinical trial for PRX005, the Phase 1 clinical trial for PRX012, and potential additional clinical trials for these and other programs;

•develop and possibly commercialize our drug candidates, including birtamimab, prasinezumab, PRX005, PRX012, and our dual Aβ-Tau vaccine;

•undertake nonclinical development of other drug candidates and initiate clinical trials, if supported by nonclinical data;

•pursue our early stage research and seek to identify additional drug candidates; and

•potentially acquire rights from third parties to drug candidates or technologies through licenses, acquisitions, or other means.

We must generate significant revenue to achieve and maintain profitability. Even if we succeed in discovering, developing, and commercializing one or more drug candidates, we may not be able to generate sufficient revenue and we may never be able to achieve or sustain profitability.

We will require additional capital to fund our operations, and if we are unable to obtain such capital, we will be unable to successfully develop and commercialize drug candidates.

As of September 30, 2021, we had cash and cash equivalents of $600.1 million. Although we believe, based on our current business plans, that our existing cash and cash equivalents will be sufficient to meet our obligations for at least the next twelve months, we anticipate that we will require additional capital in order to continue the research and development, and eventual commercialization, of our drug candidates. Our future capital requirements will depend on many factors that are currently unknown to us, including, without limitation:

•the timing of progress, results, and costs of our clinical trials, including the Phase 3 clinical trial for birtamimab, the Phase 2 clinical trial for prasinezumab being conducted by Roche, the Phase 2b clinical trial for prasinezumab being conducted by Roche, the Phase 2 clinical trial for PRX004 being conducted by Novo Nordisk, the Phase 1 clinical trial for PRX005, and the Phase 1 clinical trial for PRX012;

•the timing, initiation, progress, results, and costs of these and our other research, development, and possible commercialization activities;

•the results of our research and nonclinical and clinical studies;

•the costs of manufacturing our drug candidates for clinical development as well as for future commercialization needs;

•if and when appropriate, the costs of preparing for commercialization of our drug candidates;

•the costs of preparing, filing, and prosecuting patent applications, and maintaining, enforcing, and defending intellectual property-related claims;

•our ability to establish strategic collaborations, licensing, or other arrangements;

•the costs to satisfy our obligations under current and potential future collaborations; and

•the timing, receipt, and amount of revenues or royalties, if any, from any approved drug candidates.

We have based our expectations relating to liquidity and capital resources on assumptions that may prove to be wrong, and we could use our available capital resources sooner than we currently expect. Because of the numerous risks and uncertainties associated with the development and commercialization of our drug candidates, we are unable to estimate the amounts of increased capital outlays and operating expenses associated with completing the development and commercialization of our current drug candidates.

In the pharmaceutical industry, the research and development process is lengthy and involves a high degree of risk and uncertainty. This process is conducted in various stages and, during each stage, there is substantial risk that drug candidates in our research and development pipeline will experience difficulties, delays or failures. This makes it difficult to estimate the total costs to complete our clinical trials and to estimate anticipated completion dates with any degree of accuracy, which raises concerns that attempts to quantify costs and provide estimates of timing may be misleading by implying a greater degree of certainty than actually exists.

In order to develop and obtain regulatory approval for our drug candidates we will need to raise substantial additional funds. We expect to raise any such additional funds through public or private equity or debt financings, collaborative agreements with corporate partners, or other arrangements. We cannot assure that additional funds will be available when we need them on terms that are acceptable to us or at all. If we raise additional funds by issuing equity securities, including under our ATM, substantial dilution to existing shareholders would result. If we raise additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations as well as covenants and specific financial ratios that may restrict our ability to operate our business. We may be required to relinquish rights to our technologies or drug candidates or grant licenses on terms that are not favorable to us in order to raise additional funds through strategic alliances, joint ventures, or licensing arrangements.

If adequate funds are not available on a timely basis, we may be required to:

•terminate or delay clinical trials or other development activities for one or more of our drug candidates;

•delay arrangements for activities that may be necessary to commercialize our drug candidates;

•curtail or eliminate our drug research and development programs that are designed to identify new drug candidates; or

•cease operations.

In addition, if we do not meet our payment obligations to third parties as they come due, we may be subject to litigation claims. Even if we are successful in defending against these claims, litigation could result in substantial costs and distract management and may have unfavorable results that could further adversely impact our financial condition.

The COVID-19 pandemic has adversely affected our business and could have a material adverse effect on our liquidity, results of operations, financial condition or business, including our nonclinical and clinical development programs.

The outbreak of the novel strain of coronavirus SARS-CoV-2, which causes coronavirus disease (“COVID-19”), continues to be a global pandemic. While it is not possible at this time to estimate the overall impact that COVID-19 could have on our business, the continued rapid spread of COVID-19, the emergence of variant strains, and the measures taken by the governments and local authorities of affected countries and local jurisdictions, has disrupted our Phase 2 clinical trial for prasinezumab and could disrupt and delay our planned clinical trials, our research and nonclinical studies, the manufacture or shipment of both drug substance and finished drug product for our drug candidates for preclinical testing and clinical trials and materially adversely impact our liquidity, results of operations, financial condition, or business, including the following:

•our Phase 2 clinical trial for prasinezumab has been disrupted and this and other clinical trials pursued by us and our collaboration partners may be further delayed or interrupted, including as a result of (i) interruptions of supply to clinical trial sites of drug candidate or other equipment or materials, (ii) inability or unwillingness of site investigators or other study personnel to travel to study sites, dispense drug product, or otherwise treat or monitor study participants or follow study protocols, or conduct necessary data collection or verification, (iii) inability or unwillingness of study participants to travel to clinical trial sites, receive infusions, or otherwise continue to participate in the study, (iv) diversion of healthcare resources away from the conduct of clinical trials, including the diversion of hospitals serving as our clinical trial sites and hospital staff supporting the conduct of our clinical trials, or (v) interruptions in contracting with essential third-party vendors;

•we, or our collaboration partners, may be delayed in or prevented from initiating new clinical trials of current or prospective drug candidates because of (i) delays or difficulties in manufacturing drug product, (ii) delays or difficulties preparing regulatory submissions, (iii) delays or difficulties contracting with essential third-party vendors (such as contract research organizations), (iv) delays or difficulties enlisting site investigators or initiating clinical trial sites, (v) delays or difficulties recruiting or enrolling study participants, or (vi) delays or difficulties supplying drug product or other equipment or materials to clinical trial sites or other locations;

•we may experience delays or interruptions in our business operations due to our key personnel, or a significant number of our personnel, becoming infected with COVID-19 and therefore being unable to work, even remotely, for an extended period of time;

•interruption or delays in the operations of the U.S. Food and Drug Administration (the “FDA”) and comparable foreign regulatory agencies may impact review, inspection, and approval timelines for any of our development programs;

•the pandemic may adversely affect our collaboration partners, Roche, Bristol Myers Squibb (“BMS”), and/or Novo Nordisk, in ways that adversely impacts our collaborations with them;

•business development opportunities may become more limited or difficult to undertake;

•our costs may significantly increase to manage impacts to our business to complete our planned operations within our projected timelines;

•changes in local regulations as part of a response to COVID-19 may require us to change the ways in which our clinical trials are conducted, which may result in unexpected costs, or discontinuation of the clinical trials altogether;

•we may experience delays in necessary interactions with local regulators, ethics committees, and other important agencies and contractors due to limitations in employee resources or forced furlough of government employees; or

•our liquidity needs may be adversely impacted by the economic effects of the pandemic on financial markets.

Any one or more of these risks could have a material adverse effect on our liquidity, results of operations, financial condition or business, including the progress of, and timelines for, our nonclinical and clinical development programs.

In addition, the spread of COVID-19 has caused a broad impact globally, and may materially affect us economically. For example, if the subtenant to the office space that we subleased in South San Francisco, California defaults on its payment obligations, we will not receive sublease income to offset our lease payments to the landlord of the South San Francisco office space until such time as we are able to secure a new subtenant and enter into a new sublease agreement. The spread of COVID-19 has had a negative impact on the commercial real estate market and there can be no assurance that we would be able to re-sublet the space for the same rent that the current subtenant is obligated to pay us or at all.

While the potential economic impact brought by, and the duration of, COVID-19 may be difficult to assess or predict, a widespread pandemic could result in significant disruption of global financial markets, reducing our ability to access capital, which could in the future negatively affect our liquidity. In addition, a recession or market correction resulting from the spread of COVID-19 could materially affect our business and the market price of our ordinary shares.

The United Kingdom’s withdrawal from the European Union could have a negative effect on global economic conditions and financial markets, European Union regulatory procedures and our business.

Following a national referendum and enactment of legislation by the government of the United Kingdom, the United Kingdom formally withdrew from the European Union (“EU”) on January 31, 2020, commonly referred to as Brexit. The United Kingdom remained in the EU customs union and the single market for a transition period which expired on December

31, 2020. On December 24, 2020, the United Kingdom and the EU reached agreement in principle on their future trading relationship and entered into the EU-UK Trade and Cooperation Agreement which was formally ratified by the parties and as of May 1, 2021, is fully in force. However, because the agreement merely sets forth a framework in many respects and will require complex additional bilateral negotiations between the United Kingdom and the EU as both parties continue to work on the rules for implementation, significant political and economic uncertainty remains as to aspects of the future relationship between the United Kingdom and the EU. The uncertainty surrounding Brexit has had and may continue to have a material adverse effect on global economic conditions and the stability of global financial markets, and may significantly reduce global market liquidity and restrict the ability of key market participants to operate in certain financial markets. Any of these factors could depress economic activity and restrict access to capital, which could have a material adverse effect on our business, financial condition, results of operations, and/or growth prospects.

Our future success depends on our ability to retain key personnel and to attract, retain, and motivate qualified personnel.

We are highly dependent on key personnel, including Dr. Gene G. Kinney, our President and Chief Executive Officer. There can be no assurance that we will be able to retain Dr. Kinney or any of our key personnel. The loss of the services of Dr. Kinney or any other person on whom we are highly dependent might impede the achievement of our research, development, and commercial objectives.

Recruiting and retaining qualified scientific and other personnel are critical to our growth and future success. Competition for qualified personnel in our industry is intense. We may not be able to attract and retain these personnel on acceptable terms given that competition. Failure to recruit and retain qualified personnel could have a material adverse effect on our business, financial condition, results of operations, and/or growth prospects.

Our collaborators, prospective collaborators, and suppliers may need assurances that our financial resources and stability on a stand-alone basis are sufficient to satisfy their requirements for doing or continuing to do business with us.

Some of our collaborators, prospective collaborators, and suppliers may need assurances that our financial resources and stability on a stand-alone basis are sufficient to satisfy their requirements for doing or continuing to do business with us. If our collaborators, prospective collaborators or suppliers are not satisfied with our financial resources and stability, it could have a material adverse effect on our ability to develop our drug candidates, enter into licenses or other agreements and on our business, financial condition or results of operations.

The agreements we entered into with Elan involve conflicts of interest and therefore may have materially disadvantageous terms to us.

We entered into certain agreements with Elan in connection with our separation from Elan, which set forth the main terms of the separation and provided a framework for our initial relationship with Elan. These agreements may have terms that are materially disadvantageous to us or are otherwise not as favorable as those that might be negotiated between unaffiliated third parties. In December 2013, Elan was acquired by Perrigo Company plc (“Perrigo”), and in February 2014 Perrigo caused Elan to sell all of its shares of Prothena in an underwritten offering. As a result of the acquisition of Elan by Perrigo and the subsequent sale of all of its shares of Prothena, Perrigo may be less willing to collaborate with us in connection with the agreements to which we and Elan are a party and other matters.

We may be adversely affected by earthquakes or other natural disasters.

Our key facility and almost all of our operations are in the San Francisco Bay Area of Northern California, which in the past has experienced severe earthquakes. If an earthquake, other natural disaster, or similar event were to occur and prevent us from using all or a significant portion of those operations or local critical infrastructure, or that otherwise disrupts our operations, it could be difficult or impossible for us to continue our business for a substantial period of time. We have disaster recovery and business continuity plans, but they may prove to be inadequate in the event of a natural disaster or similar event. We may incur substantial expenses if our disaster recovery and business continuity plans prove to be inadequate. We do not carry earthquake insurance. Furthermore, third parties upon which we are materially dependent upon may be vulnerable to natural disasters or similar events. Accordingly, such a natural disaster or similar event could have an adverse effect on our business, financial condition, or results of operations.

We may experience breaches or similar disruptions of our information technology systems or data.

Our business is increasingly dependent on critical, complex, and interdependent information technology systems to support business processes as well as internal and external communications. Despite the implementation of security measures, our internal computer systems, and those of our current and any future CROs and other contractors, consultants, and collaborators, are vulnerable to damage from cyberattacks, “phishing” attacks, ransomware, computer viruses, unauthorized

access, natural disasters, terrorism, war, and telecommunication or electrical failures. Attacks upon information technology systems are increasing in their frequency, levels of persistence, sophistication, and intensity, and are being conducted by sophisticated and organized groups and individuals with a wide range of motives and expertise. As a result of the COVID-19 pandemic, we may also face increased cybersecurity risks due to our reliance on internet technology and the number of our employees who are working remotely, which may create additional opportunities for cybercriminals to exploit vulnerabilities. Furthermore, because the techniques used to obtain unauthorized access to or to sabotage systems change frequently and often are not recognized until launched against a target, we may be unable to anticipate these techniques or implement adequate preventative measures. We may also experience security breaches that may remain undetected for an extended period. Any breakdown, malicious intrusion, or computer virus could result in the impairment of key business processes or breach of data security, which could result in a material disruption of our development programs and cause interruptions in our business operations, whether due to a loss of our trade secrets or other intellectual property or lead to unauthorized disclosure of personal data of our employees, third parties with which we do business, clinical trial participants, or others. For example, the loss of clinical trial data from completed or future clinical trials could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data. In addition, such a breach may require notification to governmental agencies, the media, or individuals pursuant to applicable data privacy and security law and regulations. Such an event could have an adverse effect on our business, financial condition, or results of operations.

Changes in and failures to comply with U.S. and foreign privacy and data protection laws, regulations, and standards may adversely affect our business, operations, and financial performance.

We and our partners may be subject to federal, state, and foreign data privacy and security laws and regulations. The legislative and regulatory landscape for privacy and data protection continues to evolve, and there has been an increasing focus on privacy and data protection issues, which may affect our business and may increase our compliance costs and exposure to liability. In the United States, numerous federal and state laws and regulations, including state security breach notification laws, federal and state health information privacy laws (including HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act, and regulations promulgated thereunder), and federal and state consumer protection laws, govern the collection, use, disclosure, and protection of personal information. Each of these laws is subject to varying interpretations by courts and government agencies, creating complex compliance issues. For example, the California Consumer Privacy Act (the “CCPA”) went into effect January 1, 2020. The CCPA, among other things, imposes new data privacy obligations on covered companies and provides expanded privacy rights to California residents, including the right to access, delete, and opt out of certain disclosures of their information. The CCPA provides for civil penalties for violations, as well as a private right of action with statutory damages for certain data breaches, which may increase the frequency and likelihood of data breach litigation. Although the law includes limited exceptions for health-related information, including clinical trial data, such exceptions may not apply to all of our operations and processing activities. Further, the California Privacy Rights Act (the “CPRA”) recently passed in California. The CPRA will impose additional data protection obligations on covered businesses, including additional consumer rights processes, limitations on data uses, new audit requirements for higher risk data, and opt outs for certain uses of sensitive data. It will also create a new California data protection agency authorized to issue substantive regulations and could result in increased privacy and information security enforcement. The majority of the provisions will go into effect on January 1, 2023, and additional compliance investment and potential business process changes may be required. In addition, the CCPA has prompted a number of proposals for new federal and state privacy legislation that, if passed, could increase our potential liability, increase our compliance costs and adversely affect our business. If we fail to comply with applicable laws and regulations we could be subject to penalties or sanctions, including criminal penalties if we knowingly obtain or disclose individually identifiable health information from a covered entity in a manner that is not authorized or permitted by HIPAA or applicable state laws.

We are also or may become subject to rapidly evolving data protection laws, rules, and regulations in foreign jurisdictions. For example, the European Union General Data Protection Regulation (the “EU GDPR”) governs the collection of, and other processing activities involving, personal data (i.e., data which identifies an individual or from which an individual is identifiable) including, clinical trial data, and grants individuals various data protection rights (e.g., the right to erasure of personal data). The EU GDPR imposes a number of obligations on companies, including inter alia: (i) accountability and transparency requirements, and enhanced requirements for obtaining valid consent; (ii) obligations to consider data protection as any new products or services are developed and to limit the amount of personal data processed; and (iii) obligations to implement appropriate technical and organizational measures to safeguard personal data and to report certain personal data breaches to the supervisory authority without undue delay (and no later than 72 hours where feasible). In addition, the EU GDPR prohibits the transfer of personal data from the European Economic Area (“EEA”) to the United States and other jurisdictions that the European Commission does not recognize as having “adequate” data protection laws unless a data transfer mechanism has been put in place. In July 2020, the Court of Justice of the European Union limited how organizations could lawfully transfer personal data from the EEA to the United States by invalidating the EU-US Privacy Shield for purposes of international transfers and imposing further restrictions on the use of standard contractual clauses (“SCCs”) including, a requirement for companies to carry out a transfer privacy impact assessment, which among other things, assesses the laws

governing access to personal data in the recipient country and considers whether supplementary measures that provide privacy protections additional to those provided under the SCCs will need to be implemented to ensure an essentially equivalent level of data protection to that afforded in the EEA. The EU GDPR imposes substantial fines for breaches and violations (up to the greater of €20 million or 4% of our annual global revenue). The EU GDPR also confers a private right of action on data subjects and consumer associations to lodge complaints with supervisory authorities, seek judicial remedies, and obtain compensation for damages resulting from violations of the EU GDPR. Relatedly, following the United Kingdom’s withdrawal from the EU (i.e., Brexit), and the expiry of the Brexit transition period, which ended on December 31, 2020, the EU GDPR has been implemented in the United Kingdom (as the “UK GDPR”). The UK GDPR sits alongside the UK Data Protection Act 2018 which implements certain derogations in the EU GDPR into UK law. Under the UK GDPR, companies not established in the UK but who process personal data in relation to the offering of goods or services to individuals in the UK, or to monitor their behavior will be subject to the UK GDPR – the requirements of which are (at this time) largely aligned with those under the EU GDPR and as such, may lead to similar compliance and operational costs with potential fines up to the greater of £17.5 million or 4% of global turnover. The above-described changes lead to additional costs and increase our overall risk exposure.

Compliance with U.S. and foreign data privacy and security laws, rules, and regulations could require us to take on more onerous obligations in our contracts, require us to engage in costly compliance exercises, restrict our ability to collect, use and disclose data, or in some cases, impact our or our partners’ or suppliers’ ability to operate in certain jurisdictions. Each of these constantly evolving laws can be subject to varying interpretations. If we fail to comply with any such laws, rules, or regulations, we may face government investigations and/or enforcement actions, fines, civil or criminal penalties, private litigation, or adverse publicity that could adversely affect our business, financial condition, and results of operations.

Risks Related to the Discovery, Development, and Regulatory Approval of Drug Candidates

Our success is largely dependent on the success of our research and development programs. Our drug candidates are in various stages of development and we may not be able to successfully discover, develop, obtain regulatory approval for, or commercialize any drug candidates.

The success of our business depends substantially upon our ability to discover, develop, obtain regulatory approval for and commercialize our drug candidates successfully. Our research and development programs are prone to the significant and likely risks of failure inherent in drug development, which can result from the failure of the drug candidate to be sufficiently effective, the safety profile of the drug candidate, a clinical trial that is not sufficiently enrolled or powered or adequately designed to detect a drug effect, or other reasons. We intend to continue to invest most of our time and financial resources in our research and development programs.

There is no assurance that the results of the Phase 3 clinical trial for birtamimab, the Phase 2 clinical trial for prasinezumab, the Phase 2b clinical trial for prasinezumab, the Phase 2 clinical trial for PRX004, the Phase 1 clinical trial for PRX005, and the Phase 1 clinical trial for PRX012 will support further development of these drug candidates. In addition, we currently do not, and may never, have any other drug candidates in clinical trials, and we have not identified drug candidates for many of our research programs.

Before obtaining regulatory approvals for the commercial sale of any drug candidate for a target indication, we must demonstrate with substantial evidence gathered in adequate and well-controlled clinical trials that the drug candidate is safe and effective for use for that target indication. In the U.S., this must be done to the satisfaction of the FDA; in the EU, this must be done to the satisfaction of the European Medicines Agency (the “EMA”); and in other countries this must be done to the satisfaction of comparable regulatory authorities.

Satisfaction of these and other regulatory requirements is costly, time consuming, uncertain, and subject to unanticipated delays. Despite our efforts, our drug candidates may not:

•offer improvement over existing treatment options;

•be proven safe and effective in clinical trials; or

•meet applicable regulatory standards.

Positive results in nonclinical studies of a drug candidate may not be predictive of similar results in humans during clinical trials, and promising results from early clinical trials of a drug candidate may not be replicated in later clinical trials. Interim results of a clinical trial do not necessarily predict final results. A number of companies in the pharmaceutical and biotechnology industries have suffered significant setbacks in late-stage clinical trials even after achieving promising results in early-stage development. Accordingly, the results from completed nonclinical studies and early clinical trials for our drug candidates may not be predictive of the results we may obtain in later stage studies or trials. Our nonclinical studies or clinical

trials may produce negative or inconclusive results, and we may decide, or regulators may require us, to conduct additional nonclinical studies or clinical trials, or to discontinue clinical trials altogether.

Furthermore, we have not marketed, distributed, or sold any products. Our success will, in addition to the factors discussed above, depend on the successful commercialization of any drug candidates that obtain regulatory approval. Successful commercialization may require:

•obtaining and maintaining commercial manufacturing arrangements with third-party manufacturers;

•developing the marketing and sales capabilities, internal and/or in collaboration with pharmaceutical companies or contract sales organizations, to market and sell any approved drug; and

•acceptance of any approved drug in the medical community and by patients and third-party payers.

Many of these factors are beyond our control. We do not expect any of our drug candidates to be commercially available for several years and some or all may never become commercially available. Accordingly, we may never generate revenues through the sale of products.

We have entered into collaborations with Roche and BMS and may enter into additional collaborations in the future, and we might not realize the anticipated benefits of such collaborations.

Research, development, commercialization and/or strategic collaborations, including those that we have with Roche and BMS, are subject to numerous risks, which include the following:

•collaborators may have significant control or discretion in determining the efforts and resources that they will apply to a collaboration, and might not commit sufficient efforts and resources or might misapply those efforts and resources;

•we may have limited influence or control over the approaches to research, development, and/or commercialization of products candidates in the territories in which our collaboration partners lead research, development, and/or commercialization;

•collaborators might not pursue research, development, and/or commercialization of collaboration drug candidates or might elect not to continue or renew research, development, and/or commercialization programs based on nonclinical and/or clinical trial results, changes in their strategic focus due to the acquisition of competing products, availability of funding, or other factors, such as a business combination that diverts resources or creates competing priorities;

•collaborators might delay, provide insufficient resources to, or modify or stop research or clinical development for collaboration drug candidates or require a new formulation of a drug candidate for clinical testing;

•collaborators could develop or acquire products outside of the collaboration that compete directly or indirectly with our drug candidates or require a new formulation of a drug candidate for nonclinical and/or clinical testing;

•collaborators with sales, marketing, and distribution rights to one or more drug candidates might not commit sufficient resources to sales, marketing, and distribution or might otherwise fail to successfully commercialize those drug candidates;

•collaborators might not properly maintain or defend our intellectual property rights or might use our intellectual property improperly or in a way that jeopardizes our intellectual property or exposes us to potential liability;

•collaboration activities might result in the collaborator having intellectual property covering our activities or drug candidates, which could limit our rights or ability to research, develop, and/or commercialize our drug candidates;

•collaborators might not be in compliance with laws applicable to their activities under the collaboration, which could impact the collaboration or us;

•disputes might arise between us and a collaborator that could cause a delay or termination of the collaboration or result in costly litigation that diverts management attention and resources; and

•collaborations might be terminated, which could result in a need for additional capital to pursue further research, development, and/or commercialization of our drug candidates.

In addition, funding provided by a collaborator might not be sufficient to advance drug candidates under the collaboration.

If a collaborator terminates a collaboration or a program under a collaboration, including by failing to exercise a license or other option under the collaboration, whether because we fail to meet a milestone or otherwise, any potential revenue from the collaboration would be significantly reduced or eliminated. In addition, we will likely need to either secure other funding to advance research, development, and/or commercialization of the relevant drug candidate or abandon that program, the development of the relevant drug candidate could be significantly delayed, and our cash expenditures could increase significantly if we are to continue research, development, and/or commercialization of the relevant drug candidates.

Any one or more of these risks, if realized, could reduce or eliminate future revenue from drug candidates under our collaborations, and could have a material adverse effect on our business, financial condition, results of operations, and/or growth prospects.

If clinical trials of our drug candidates are prolonged, delayed, suspended, or terminated, we may be unable to commercialize our drug candidates on a timely basis, if at all, which would require us to incur additional costs and delay or prevent our receipt of any revenue from potential product sales.

We cannot predict whether we will encounter problems with the Phase 3 clinical trial for birtamimab, the Phase 2 clinical trial for prasinezumab, the Phase 2b clinical trial for prasinezumab, the Phase 2 clinical trial for PRX004, the Phase 1 clinical trial for PRX005, the Phase 1 clinical trial for PRX012, or any other future clinical trials that will cause us or any regulatory authority to delay, suspend or terminate those clinical trials or delay the analysis of data derived from them. A number of events, including any of the following, could delay the completion of our ongoing or planned clinical trials and negatively impact our ability to obtain regulatory approval for, and to market and sell, a particular drug candidate:

•conditions imposed on us by the FDA, the EMA, or other comparable regulatory authorities regarding the scope or design of our clinical trials;

•delays in obtaining, or our inability to obtain, required approvals from institutional review boards (“IRBs”) or other reviewing entities at clinical sites selected for participation in our clinical trials;

•insufficient supply or deficient quality of our drug candidates or other materials necessary to conduct our clinical trials;

•delays in obtaining regulatory authority authorization for the conduct of our clinical trials;

•lower than anticipated enrollment and/or retention rate of subjects in our clinical trials, which can be impacted by a number of factors, including size of patient population, design of trial protocol, trial length, eligibility criteria, perceived risks and benefits of the drug candidate, patient proximity to trial sites, patient referral practices of physicians, availability of other treatments for the relevant disease, and competition from other clinical trials;

•slower than expected rates of events in trials with a composite primary endpoint that is event-based;

•serious and unexpected drug-related side effects experienced by subjects in clinical trials; or

•failure of our third-party contractors and collaborators to meet their contractual obligations to us or otherwise meet their development or other objectives in a timely manner.

Further, conducting clinical trials in foreign countries, as we do and may continue do for our drug candidates, presents potential additional risks for our clinical trials. These risks include the failure in foreign countries to adhere to clinical protocol as a result of differences in regional or local healthcare services or customs, obtaining clinical data and/or clinical samples from sites in such foreign countries, managing additional administrative burdens associated with foreign regulatory requirements, as well as political and economic risks relevant to such foreign countries.

We are dependent upon Roche with respect to further development of prasinezumab. Under the terms of our collaboration with Roche, Roche is responsible for that further development, including the conduct of the ongoing Phase 2 and Phase 2b clinical trials and any future clinical trial of that drug candidate.

We are dependent upon Novo Nordisk with respect to further development of PRX004, including the Phase 2 clinical trial and any future clinical trial of that drug candidate.

Clinical trials may also be delayed or terminated as a result of ambiguous or negative data or results. In addition, a clinical trial may be delayed, suspended or terminated by us, the FDA, the EMA or other comparable regulatory authorities, the IRBs at the sites where the IRBs are overseeing a trial, or the safety oversight committee overseeing the clinical trial at issue due to a number of factors, including:

•failure to conduct the clinical trial in accordance with regulatory requirements or our clinical protocols;

•inspection of the clinical trial operations or trial sites by the FDA, the EMA, or other regulatory authorities resulting in the imposition of a clinical hold on or imposition of additional conditions for the conduct of the trial;

•interpretation of data by the FDA, the EMA, or other regulatory authorities;

•requirement by the FDA, the EMA, or other regulatory authorities to perform additional studies;

•failure to achieve primary or secondary endpoints or other failure to demonstrate efficacy or adequate safety;

•unforeseen safety issues; or

•lack of adequate funding to continue the clinical trial.

Additionally, changes in regulatory requirements and guidance may occur and we may need to amend clinical trial protocols to reflect these changes. Amendments may require us to resubmit our clinical trial protocols to regulatory authorities and IRBs for reexamination, which may impact the cost, timing, or successful completion of a clinical trial.

We do not know whether our clinical trials will be conducted as planned, will need to be restructured, or will be completed on schedule, if at all. Delays in our clinical trials will result in increased development costs for our drug candidates. In addition, if we experience delays in the completion of, or if we terminate, any of our clinical trials, the commercial prospects for our drug candidates may be delayed or harmed and our ability to generate product revenues will be delayed or jeopardized. Furthermore, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of a drug candidate.

The regulatory approval processes of the FDA, the EMA, and other comparable regulatory authorities are lengthy, time consuming, and inherently unpredictable, and if we are ultimately unable to obtain regulatory approval for our drug candidates, our business will be substantially harmed.

The time required to obtain approval by the FDA, the EMA, and other comparable regulatory authorities is inherently unpredictable but typically takes many years following the commencement of clinical trials and depends upon numerous factors, including the substantial discretion of the regulatory authorities. In addition, approval policies, regulations, or the type and amount of clinical data necessary to gain approval may change during the course of a drug candidate’s clinical development and may vary among jurisdictions. We have not obtained regulatory approval for any drug candidate, and it is possible that none of our existing drug candidates or any drug candidates we may seek to develop in the future will ever obtain regulatory approval.

Our drug candidates could fail to receive regulatory approval for many reasons, including the following:

•the FDA, the EMA, or comparable regulatory authorities may disagree with the design, implementation, or conduct of our clinical trials;

•we may be unable to demonstrate to the satisfaction of the FDA, the EMA, or comparable regulatory authorities that a drug candidate is safe and effective for its proposed indication;

•the results of clinical trials may not meet the level of statistical significance required by the FDA, the EMA, or comparable regulatory authorities for approval;

•we may be unable to demonstrate that a drug candidate’s clinical and other benefits outweigh its safety risks;

•the FDA, the EMA, or comparable regulatory authorities may disagree with our interpretation of data from nonclinical studies or clinical trials;

•the data collected from clinical trials of our drug candidates may not be sufficient to support the submission of a New Drug Application (“NDA”) or a Biologic License Application (“BLA”) to the FDA, a Marketing Authorization Application (“MAA”) to the EMA, or similar applications to comparable regulatory authorities;

•the FDA, the EMA, or comparable regulatory authorities may fail to approve the manufacturing processes or facilities of third-party manufacturers with which we contract for clinical and commercial supplies; or

•the approval policies or regulations of the FDA, the EMA, or comparable regulatory authorities may significantly change in a manner rendering our clinical data insufficient for approval.

This lengthy approval process as well as the unpredictability of future clinical trial results may result in our failing to obtain regulatory approval to market our drug candidates, which would significantly harm our business, results of operations, and/or growth prospects.

Separately, in response to the COVID-19 pandemic, on March 10, 2020, the FDA announced its intention to postpone most inspections of foreign manufacturing facilities and products through April 2020, and on March 18, 2020, the FDA temporarily postponed routine surveillance inspections of domestic manufacturing facilities. Subsequently, on July 10, 2020, the FDA announced its intention to resume certain on-site inspections of domestic manufacturing facilities subject to a risk-based prioritization system. In May 2021, the FDA updated its guidance, first published in August 2020, clarifying how it intends to conduct inspections during the COVID-19 pandemic, including how it plans to determine which inspections are “mission critical.” The FDA intends to use this risk-based assessment system to identify the categories of regulatory activity that can occur within a given geographic area, ranging from mission critical inspections to resumption of all regulatory activities. Regulatory authorities outside the United States may adopt similar restrictions or other policy measures in response to the COVID-19 pandemic, including providing guidance regarding the conduct of clinical trials. If global health concerns continue to prevent the FDA or other regulatory authorities from conducting their regular inspections, or impact reviews or other regulatory activities, it could significantly impact the ability of the FDA or other regulatory authorities to timely review and process our regulatory submissions, which could have a material adverse effect on our business.

In addition, even if we were to obtain approval, regulatory authorities may approve any of our drug candidates for fewer or more limited indications than we request, may grant approval contingent on the performance of costly post-marketing clinical trials, or may approve a drug candidate with a label that does not include the labeling claims necessary or desirable for the successful commercialization of that drug candidate. Any of the foregoing scenarios could materially harm the commercial prospects for our drug candidates.

The FDA or other comparable foreign regulatory authorities may not accept data from trials conducted in locations outside of their jurisdiction.

We are and may choose to conduct international clinical trials in the future. The acceptance of study data by the FDA or other comparable foreign regulatory authority from clinical trials conducted outside of their respective jurisdictions may be subject to certain conditions. In cases where data from foreign clinical trials are intended to serve as the basis for marketing approval in the United States, the FDA will generally not approve the application on the basis of foreign data alone unless (1) the data are applicable to the United States population and United States medical practice; (2) the trials are performed by clinical investigators of recognized competence; and (3) the data may be considered valid without the need for an on-site inspection by the FDA, or if the FDA considers such an inspection to be necessary, the FDA is able to validate the data through an on-site inspection or other appropriate means. In addition, such foreign trials would be subject to the applicable local laws of the foreign jurisdictions where the trials are conducted. There can be no assurance that the FDA or any other comparable foreign regulatory authority will accept data from trials conducted outside of its applicable jurisdiction. If the FDA or any other comparable foreign regulatory authority does not accept such data, it would result in the need for additional trials, which would be costly and time-consuming and delay aspects of our business plan, and which may result in our product candidates not receiving approval for commercialization in the applicable jurisdiction.

Even if our drug candidates receive regulatory approval in one country or jurisdiction, we may never receive approval or commercialize our products in other countries or jurisdictions.

In order to market drug candidates in a particular country or jurisdiction, we must establish and comply with numerous and varying regulatory requirements of that country or jurisdiction, including with respect to safety and efficacy. Approval procedures vary among countries and can involve additional product testing and additional administrative review periods. The time required to obtain approval in other countries might differ from that required to obtain, for example, FDA approval in the U.S. or EMA approval in the EU. The regulatory approval process in other countries may include all of the risks detailed above regarding FDA approval in the U.S. and EMA approval in the EU as well as other risks. Regulatory approval in one country or jurisdiction does not ensure regulatory approval in another country or jurisdiction, but a failure or delay in obtaining regulatory approval in one country may have a negative effect on the regulatory process in others. Failure to obtain regulatory approval in one country or jurisdiction or any delay or setback in obtaining such approval would impair our ability to develop other markets for that drug candidate.

Although we have obtained agreement with the FDA on a special protocol assessment (“SPA”) with regard to our Phase 3 AFFIRM-AL trial of birtamimab, an SPA does not guarantee approval of birtamimab or any other particular outcome from regulatory review.

On January 27, 2021, the FDA agreed to an SPA for our Phase 3 AFFIRM-AL clinical trial of birtamimab. The FDA’s SPA process is designed to facilitate the FDA’s review and approval of drugs by allowing the FDA to evaluate proposed critical design features of certain clinical trials that are intended to form the primary basis for determining a drug candidate’s efficacy and safety. Upon specific request by a clinical trial sponsor, the FDA will evaluate the study protocol and statistical analysis plan and respond to a sponsor’s questions regarding protocol design and scientific and regulatory requirements. FDA aims to complete SPA reviews within 45 days of receipt of the request. The FDA ultimately assesses whether specific elements of the

protocol design for the trial, such as entry criteria, endpoints, size, duration, and planned analyses, are acceptable to support an application for regulatory approval of the drug candidate with respect to the effectiveness of and safety for the indication studied. All agreements and disagreements between the FDA and the sponsor regarding a SPA must be clearly documented in an SPA letter or the minutes of a meeting between the sponsor and the FDA.

Although the FDA has agreed to the SPA for our Phase 3 AFFIRM-AL clinical trial with respect to the primary endpoint and certain other aspects of the clinical trial, a SPA agreement does not guarantee approval of a drug candidate. The FDA may limit the scope of its agreement to an SPA agreement to certain, specific aspects of the clinical trial design. Even if the FDA agrees to the design, execution, and analysis proposed in a protocol reviewed under the SPA process, the FDA may revoke or alter its agreement in certain circumstances. In particular, a SPA agreement is not binding on the FDA if public health concerns emerge that were unrecognized at the time of the SPA agreement, other new scientific concerns regarding product safety or efficacy arise, the sponsor fails to comply with the agreed upon study protocol, or the relevant data, assumptions, or information provided by the sponsor in a request for the SPA change or are found to be false or to omit relevant facts. In addition, even after a SPA agreement is finalized, the SPA agreement may be modified, and such modification will be deemed binding on the FDA review division, except under the circumstances described above, if the FDA and the sponsor agree in writing to the modification of the study protocol and/or statistical analysis plan. Generally, such modification is intended to improve the study. The FDA retains significant latitude and discretion in interpreting the terms of the SPA agreement and the data and results from any study that is the subject of the SPA agreement.

Moreover, if the FDA revokes or alters its agreement under the SPA, or interprets the data collected from the clinical trial differently than the sponsor, the FDA may not deem the data sufficient to support an application for regulatory approval.

Both before and after marketing approval, our drug candidates are subject to ongoing regulatory requirements and continued regulatory review, and if we fail to comply with these continuing requirements, we could be subject to a variety of sanctions and the sale of any approved products could be suspended.

Both before and after regulatory approval to market a particular drug candidate, adverse event reporting, manufacturing, labeling, packaging, storage, distribution, advertising, promotion, record keeping, and reporting related to the product are subject to extensive, ongoing regulatory requirements. These requirements include submissions of safety and other post-marketing information and reports, as well as continued compliance with current good manufacturing practice (“cGMP”) requirements and current good clinical practice (“cGCP”) requirements for any clinical trials that we conduct. Any regulatory approvals that we receive for our drug candidates may also be subject to limitations on the approved indicated uses for which the product may be marketed or to the conditions of approval, or contain requirements for potentially costly post-marketing testing, including Phase 4 clinical trials, and surveillance to monitor the safety and efficacy of the drug candidate. Later discovery of previously unknown problems with a product, including adverse events of unanticipated severity or frequency, or not previously observed in clinical trials, or problems with our third-party manufacturers or manufacturing processes, or failure to comply with the regulatory requirements of the FDA, the EMA, or other comparable regulatory authorities could subject us to administrative or judicially imposed sanctions, including:

•restrictions on the marketing of our products or their manufacturing processes;

•warning letters;

•civil or criminal penalties;

•fines;

•injunctions;

•product seizures or detentions;

•import or export bans;

•voluntary or mandatory product recalls and related publicity requirements;

•suspension or withdrawal of regulatory approvals;

•total or partial suspension of production; and

•refusal to approve pending applications for marketing approval of new products or supplements to approved applications.

The policies of the FDA, the EMA, or other comparable regulatory authority may change and additional government regulations may be enacted that could prevent, limit or delay regulatory approval of our drug candidates. If we are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we are not able to

maintain regulatory compliance, we may lose any marketing approval that we may have obtained, which would adversely affect our business, prospects and ability to achieve or sustain profitability.

If side effects are identified during the time our drug candidates are in development, or, if they are approved by applicable regulatory authorities, after they are on the market, we may choose to or be required to perform lengthy additional clinical trials, discontinue development of the affected drug candidate, change the labeling of any such products, or withdraw any such products from the market, any of which would hinder or preclude our ability to generate revenues.

Undesirable side effects caused by our drug candidates could cause us or regulatory authorities to interrupt, delay or halt clinical trials and could result in a more restrictive label or the delay or denial of regulatory approval by the FDA, the EMA, or other comparable regulatory authorities. Drug-related side effects could affect patient recruitment or the ability of enrolled patients to complete a trial or result in potential product liability claims. Any of these occurrences may harm our business, financial condition and prospects significantly. Even if any of our drug candidates receives marketing approval, as greater numbers of patients use a drug following its approval, an increase in the incidence or severity of side effects or the incidence of other post-approval problems that were not seen or anticipated during pre-approval clinical trials could result in a number of potentially significant negative consequences, including:

•regulatory authorities may withdraw their approval of the product;

•regulatory authorities may require the addition of labeling statements, such as contraindications, warnings, or precautions; or impose additional safety monitoring or reporting requirements;

•we may be required to change the way the product is administered, or to conduct additional clinical trials;

•we could be sued and held liable for harm caused to patients; and

•our reputation may suffer.

Any of these events could substantially increase the costs and expenses of developing, commercializing and marketing any such drug candidates or could harm or prevent sales of any approved products.

We deal with hazardous materials and must comply with environmental laws and regulations which can be expensive and restrict how we do business.

Some of our research and development activities involve the controlled storage, use, and disposal of hazardous materials. We are subject to U.S. federal, state, local, and other countries’ and jurisdictions’ laws and regulations governing the use, manufacture, storage, handling, and disposal of these hazardous materials. Although we believe that our safety procedures for the handling and disposing of these materials comply with the standards prescribed by these laws and regulations, we cannot eliminate the risk of accidental contamination or injury from these materials. In the event of an accident, state or federal authorities may curtail our use of these materials, and we could be liable for any civil damages that result, which may exceed our financial resources and may seriously harm our business. Because we believe that our laboratory and materials handling policies and practices sufficiently mitigate the likelihood of materials liability or third-party claims, we currently carry no insurance covering such claims. An accident could damage, or force us to shut down, our operations.

Risks Related to the Commercialization of Our Drug Candidates

Even if any of our drug candidates receives regulatory approval, if such approved product does not achieve broad market acceptance, the revenues that we generate from sales of the product will be limited.

Even if any drug candidates we may develop or acquire in the future obtain regulatory approval, they may not gain broad market acceptance among physicians, healthcare payers, patients and the medical community. The degree of market acceptance for any approved drug candidate will depend on a number of factors, including:

•the indication and label for the product and the timing of introduction of competitive products;

•demonstration of clinical safety and efficacy compared to other products;

•prevalence, frequency, and severity of adverse side effects;

•availability of coverage and adequate reimbursement from managed care plans and other third-party payers;

•convenience and ease of administration;

•cost-effectiveness;

•other potential advantages of alternative treatment methods; and

•the effectiveness of marketing and distribution support of the product.

Consequently, even if we discover, develop, and commercialize a product, the product may fail to achieve broad market acceptance and we may not be able to generate significant revenue from the product.

The success of prasinezumab in the United States, if approved, will be dependent upon the strength and performance of our collaboration with Roche. If we fail to maintain our existing collaboration with Roche, such termination would likely have a material adverse effect on our ability to develop and commercialize prasinezumab and our business. Furthermore, in May 2021, we opted out of profit and loss sharing with Roche for prasinezumab in Parkinson’s disease; however if we opt out of profit and loss sharing for any other Licensed Products and/or indications, our revenues from such other Licensed Products and/or indications will be reduced.

The success of sales of prasinezumab in the U.S. will be dependent on the ability of Roche to successfully develop in collaboration with us, and launch and commercialize prasinezumab, if approved by the FDA, pursuant to the License Agreement we entered into in December 2013. Our collaboration with Roche is complex, particularly with respect to future U.S. commercialization of prasinezumab, with respect to financial provisions, allocations of responsibilities, cost estimates, and the respective rights of the parties in decision making. Accordingly, significant aspects of the development and commercialization of prasinezumab require Roche to execute its responsibilities under the arrangement, or require Roche’s agreement or approval, prior to implementation, which could cause significant delays that may materially impact the potential success of prasinezumab in the U.S. In addition, Roche may under some circumstances independently develop products that compete with prasinezumab, or Roche may decide to not commit sufficient resources to the development, commercialization, marketing and distribution of prasinezumab. If we are not able to collaborate effectively with Roche on plans and efforts to develop and commercialize prasinezumab, our business could be materially adversely affected.

Furthermore, the terms of the License Agreement provide that Roche has the ability to terminate such arrangement for any reason after the first anniversary of the License Agreement at any time upon 90 days’ notice (if prior to first commercial sale) or 180 days’ notice (if after first commercial sale). For example, even if prasinezumab was approved by the FDA, Roche may determine that the outcomes of clinical trials made prasinezumab a less attractive commercial product and terminate our collaboration. If the License Agreement is terminated, our business and our ability to generate revenue from sales of prasinezumab could be substantially harmed as we will be required to develop, commercialize, and build our own sales and marketing organization, or enter into another strategic collaboration in order to develop and commercialize prasinezumab in the U.S. Such efforts may not be successful and, even if successful, would require substantial time and resources to carry out.

The manner in which Roche launches prasinezumab, if approved by the FDA, including the timing of launch and potential pricing, will have a significant impact on the ultimate success of prasinezumab in the U.S., and the success of the overall commercial arrangement with Roche. If launch of commercial sales of prasinezumab in the U.S. by Roche is delayed or prevented, our revenue will suffer and our stock price may decline. Further, if launch and resulting sales by Roche are not deemed successful, our business would be harmed and our stock price may decline. Any lesser effort by Roche in its prasinezumab sales and marketing efforts may result in lower revenue and thus lower profits with respect to the U.S. The outcome of Roche’s commercialization efforts in the U.S. could also have a negative effect on investors’ perception of potential sales of prasinezumab outside of the U.S., which could also cause a decline in our stock price.

In May 2021, we opted out of profit and loss sharing with Roche for prasinezumab in Parkinson’s disease. However, pursuant to the License Agreement, we are responsible for 30% of all development and commercialization costs for any future Licensed Products and/or indications (other than Parkinson’s disease with prasinezumab) that we opt to co-develop, in each case unless we elect to opt out of profit and loss sharing. If we elect to opt out of profit and loss sharing, we will instead receive sales milestones and royalties, and our revenue, if any, from such other Licensed Products and/or indications will be reduced.

Our right to co-develop Licensed Products and/or indications under the License Agreement (other than Parkinson’s disease with prasinezumab for which we have opted out of co-development) will terminate if we commence certain studies for a competitive product that treats Parkinson’s disease or other indications that we opted to co-develop. In addition, our right to co-promote prasinezumab and other Licensed Products will terminate if we commence a Phase 3 study for a competitive product that treats Parkinson’s disease.

Moreover, under the terms of the License Agreement, we rely on Roche to provide us estimates of their costs, revenue, and revenue adjustments and royalties, which estimates we use in preparing our quarterly and annual financial reports. If the underlying assumptions on which Roche’s estimates were based prove to be incorrect, actual results or revised estimates supplied by Roche that are materially different from the original estimates could require us to adjust the estimates included in

our reported financial results. If material, these adjustments could require us to restate previously reported financial results, which could have a negative effect on our stock price.

Our ability to receive any significant revenue from prasinezumab will be dependent on Roche’s efforts and may result in lower levels of income than if we marketed or developed our drug candidates entirely on our own. Roche may not fulfill its obligations or carry out marketing activities for prasinezumab as diligently as we would like. We could also become involved in disputes with Roche, which could lead to delays in or termination of development or commercialization activities and time-consuming and expensive litigation or arbitration. If Roche terminates or breaches the License Agreement, or otherwise decides not to complete its obligations in a timely manner, the chances of successfully developing, commercializing, or marketing prasinezumab would be materially and adversely affected.

Outside of the United States, we are solely dependent on the efforts and commitments of Roche, either directly or through third parties, to further develop and, if prasinezumab is approved by applicable regulatory authorities, commercialize prasinezumab. If Roche’s efforts are unsuccessful, our ability to generate future product sales from prasinezumab outside the United States would be significantly reduced.

Under our License Agreement, outside of the U.S., Roche has responsibility for developing and commercializing prasinezumab and any future Licensed Products targeting α-synuclein. As a consequence, any progress and commercial success outside of the U.S. is dependent solely on Roche’s efforts and commitment to the program. For example, Roche may delay, reduce, or terminate development efforts relating to prasinezumab outside of the U.S., or under some circumstances independently develop products that compete with prasinezumab, or decide not to commit sufficient resources to the commercialization, marketing, and distribution of prasinezumab.

In the event that Roche does not diligently develop and commercialize prasinezumab, the License Agreement provides us the right to terminate the License Agreement in connection with a material breach uncured for 90 days after notice thereof. However, our ability to enforce the provisions of the License Agreement so as to obtain meaningful recourse within a reasonable timeframe is uncertain. Further, any decision to pursue available remedies including termination would impact the potential success of prasinezumab, including inside the U.S., and we may choose not to terminate as we may not be able to find another partner and any new collaboration likely will not provide comparable financial terms to those in our arrangement with Roche. In the event of our termination, this may require us to develop and commercialize prasinezumab on our own, which is likely to result in significant additional expense and delay. Significant changes in Roche’s business strategy, resource commitment and the willingness or ability of Roche to complete its obligations under our arrangement could materially affect the potential success of the drug candidate. Furthermore, if Roche does not successfully develop and commercialize prasinezumab outside of the U.S., our potential to generate future revenue outside of the U.S. would be significantly reduced.

If we are unable to establish sales and marketing capabilities or enter into agreements with third parties to market and sell approved products, we may be unable to generate product revenue.

We do not currently have a fully-scaled organization for the sales, marketing, and distribution of pharmaceutical products. In order to market any products that may be approved by the FDA, the EMA, or other comparable regulatory authorities, we must build our sales, marketing, managerial, and other non-technical capabilities or make arrangements with third parties to perform these services.

We have entered into the License Agreement with Roche for the development of prasinezumab and may develop our own sales force and marketing infrastructure to co-promote prasinezumab in the U.S. for the treatment of Parkinson’s disease and any future Licensed Products approved for Parkinson’s disease in the U.S. If we exercise our co-promotion option and are unable to develop our own sales force and marketing infrastructure to effectively commercialize prasinezumab or other Licensed Products, our ability to generate additional revenue from potential sales of prasinezumab or such products in the U.S. may be harmed. In addition, our right to co-promote prasinezumab and other Licensed Products will terminate if we commence a Phase 3 study for a competitive product that treats Parkinson’s disease.

For any other products that may be approved, if we are unable to establish adequate sales, marketing, and distribution capabilities, whether independently or with third parties, we may not be able to generate product revenue and may not become profitable.

If government and third-party payers fail to provide coverage and adequate reimbursement rates for any of our drug candidates that receive regulatory approval, our revenue and prospects for profitability will be harmed.

In both U.S. and non-U.S. markets, our sales of any future products will depend in part upon the availability of reimbursement from third-party payers. Such third-party payers include government health programs such as Medicare, managed care providers, private health insurers, and other organizations. There is significant uncertainty related to the third-

party coverage and reimbursement of newly approved drugs. Coverage and reimbursement may not be available for any drug that we or our collaborators commercialize and, even if these are available, the level of reimbursement may not be satisfactory. Third-party payers often rely upon Medicare coverage policy and payment limitations in setting their own reimbursement policies. Third-party payers are also increasingly attempting to contain healthcare costs by demanding price discounts or rebates limiting both coverage and the amounts that they will pay for new drugs, and, as a result, they may not cover or provide adequate payment for our drug candidates. We might need to conduct post-marketing studies in order to demonstrate the cost-effectiveness of any future products to such payers’ satisfaction. Such studies might require us to commit a significant amount of management time and financial and other resources. Our future products might not ultimately be considered cost-effective. Adequate third-party reimbursement might not be available to enable us to maintain price levels sufficient to realize an appropriate return on investment in product development. If coverage and adequate reimbursement are not available or reimbursement is available only to limited levels, we or our collaborators may not be able to successfully commercialize any drug candidates for which marketing approval is obtained.

The regulations that govern marketing approvals, pricing, coverage, and reimbursement for new drugs vary widely from country to country. Current and future legislation may significantly change the approval requirements in ways that could involve additional costs and cause delays in obtaining approvals. Some countries require approval of the sale price of a drug before it can be marketed. In many countries, the pricing review period begins after marketing or licensing approval is granted. In some countries, prescription pharmaceutical pricing remains subject to continuing governmental control even after initial approval is granted. As a result, we or our collaborators might obtain marketing approval for a drug in a particular country, but then be subject to price regulations that delay commercial launch of the drug, possibly for lengthy time periods, and negatively impact our ability to generate revenue from the sale of the drug in that country. Adverse pricing limitations may hinder our ability to recoup our investment in one or more drug candidates, even if our drug candidates obtain marketing approval.

U.S. and other governments continue to propose and pass legislation designed to reduce the cost of healthcare. In the U.S., we expect that there will continue to be federal and state proposals to implement similar governmental controls. In addition, recent changes in the Medicare program and increasing emphasis on managed care in the U.S. will continue to put pressure on pharmaceutical product pricing. For example, in 2010, the U.S. Patient Protection and Affordable Care Act, as amended by the U.S. Health Care and Education Reconciliation Act (collectively, the “ACA”), was enacted. The ACA substantially changed the way healthcare is financed by both governmental and private insurers and significantly affects the pharmaceutical industry. Among the provisions of the ACA of importance to the pharmaceutical industry are the following:

•an annual, nondeductible fee on any entity that manufactures or imports certain branded prescription drugs and biologic agents, apportioned among these entities according to their market share in certain government healthcare programs;

•an increase in the minimum rebates a manufacturer must pay under the U.S. Medicaid Drug Rebate Program to 23.1% and 13.0% of the average manufacturer price for branded and generic drugs, respectively;

•expansion of healthcare fraud and abuse laws, including the U.S. False Claims Act and the U.S. Anti-Kickback Statute, new government investigative powers and enhanced penalties for non-compliance;

•a new Medicare Part D coverage gap discount program, under which manufacturers must now agree to offer 70 percent point-of-sale discounts off negotiated prices of applicable brand drugs to eligible beneficiaries during their coverage gap period, as a condition for the manufacturer’s outpatient drugs to be covered under Medicare Part D;

•extension of manufacturers’ Medicaid rebate liability to covered drugs dispensed to individuals who are enrolled in Medicaid managed care organizations;

•expansion of eligibility criteria for Medicaid programs by, among other things, allowing states to offer Medicaid coverage to additional individuals and by adding new mandatory eligibility categories for certain individuals with income at or below 133% of the federal poverty level, thereby potentially increasing a manufacturer’s Medicaid rebate liability;

•a licensure framework for follow-on biologic products;

•expansion of the entities eligible for discounts under the Public Health Service pharmaceutical pricing program;

•new requirements under the federal Open Payments program and its implementing regulations;

•a new requirement to annually report drug samples that manufacturers and distributors provide to physicians; and

•a new Patient-Centered Outcomes Research Institute to oversee, identify priorities in, and conduct comparative clinical effectiveness research, along with funding for such research.

In addition, other legislative changes have been proposed and adopted since the ACA was enacted. These changes include aggregate reductions to Medicare payments to providers of 2% per fiscal year, which went into effect in 2013 and will stay in effect through 2030, with the exception of a temporary suspension from May 1, 2020, through March 31, 2021, unless additional congressional action is taken. In 2013, the U.S. American Taxpayer Relief Act of 2012, among other things, further reduced Medicare payments to several types of providers and increased the statute of limitations period for the government to recover overpayments to providers from three to five years. These new laws may result in additional reductions in Medicare and other healthcare funding, which could have a material adverse effect on customers for our drugs, if approved, and, accordingly, our financial operations.

Since its enactment, there have been judicial, executive, and Congressional challenges to certain aspects of the ACA. The U.S. Supreme Court is currently reviewing the constitutionality of the ACA in its entirety, although it is unclear how the Supreme Court will rule. It is also unclear how other efforts, if any, to challenge, repeal, or replace the ACA will impact the law. The ultimate content, timing, or effect of any healthcare reform legislation on the U.S. healthcare industry is unclear.

We expect that other healthcare reform measures that may be adopted in the future may result in more rigorous coverage criteria and in additional downward pressure on the price that we receive for any approved drug. Legislation and regulations affecting the pricing of pharmaceuticals might change before our drug candidates are approved for marketing. Any reduction in reimbursement from Medicare or other government healthcare programs may result in a similar reduction in payments from private payers. The implementation of cost containment measures or other healthcare reforms may prevent us from being able to generate revenue, attain profitability or commercialize our drugs.

There can be no assurance that our drug candidates, if they are approved for sale in the U.S. or in other countries, will be considered medically reasonable and necessary for a specific indication, that they will be considered cost-effective by third-party payers, that coverage or an adequate level of reimbursement will be available, or that third-party payers’ reimbursement policies will not adversely affect our ability to sell our drug candidates profitably if they are approved for sale.

The markets for our drug candidates are subject to intense competition. If we are unable to compete effectively, our drug candidates may be rendered noncompetitive or obsolete.

The research, development, and commercialization of new drugs is highly competitive. We will face competition with respect to all drug candidates we may develop or commercialize in the future from pharmaceutical and biotechnology companies worldwide. The key factors affecting the success of any approved product will be its indication, label, efficacy, safety profile, drug interactions, method of administration, pricing, coverage, reimbursement, and level of promotional activity relative to those of competing drugs.

Furthermore, many large pharmaceutical and biotechnology companies, academic institutions, governmental agencies, and other public and private research organizations are pursuing the development of novel drugs that target the same indications we are targeting with our research and development program. We face, and expect to continue to face, intense and increasing competition as new products enter the market and advanced technologies become available. Many of our competitors have:

•significantly greater financial, technical and human resources than we have and may be better equipped to discover, develop, manufacture, and commercialize drug candidates;

•more extensive experience in nonclinical testing and clinical trials, obtaining regulatory approvals, and manufacturing and marketing pharmaceutical products;

•drug candidates that have been approved or are in late-stage clinical development; and/or

•collaborative arrangements in our target markets with leading companies and research institutions.

Competitive products may render our research and development program obsolete or noncompetitive before we can recover the expenses of developing and commercializing our drug candidates. Furthermore, the development of new treatment methods and/or the widespread adoption or increased utilization of any vaccine or development of other products or treatments for the diseases we are targeting could render any of our drug candidates noncompetitive, obsolete or uneconomical. If we successfully develop and obtain approval for a drug candidate, we will face competition based on the safety and effectiveness of the approved product, the timing of its entry into the market in relation to competitive products in development, the availability and cost of supply, marketing and sales capabilities, coverage, reimbursement, price, patent position and other factors. Even if we successfully develop drug candidates but those drug candidates do not achieve and maintain market acceptance, our business will not be successful.

Our drug candidates for which we intend to seek approval as biologic products may face competition sooner than anticipated.

Our current drug candidates are regulated by the FDA as biologic products and we intend to seek approval for these products pursuant to the BLA pathway. The U.S. Biologics Price Competition and Innovation Act of 2009 (the “BPCIA”) created an abbreviated pathway for the approval of biosimilar and interchangeable biologic products. The abbreviated regulatory pathway establishes legal authority for the FDA to review and approve biosimilar biologics, including the possible designation of a biosimilar as “interchangeable” based on its similarity to an existing brand product.

Under the BPCIA, an application for a biosimilar product cannot be submitted to the FDA until four years following the date that the reference product was first licensed by the FDA, and cannot be approved by the FDA until 12 years after the original branded product was approved under a BLA. The BPCIA also created certain exclusivity periods for biosimilars approved as interchangeable products. However, during the 12-year period of reference product exclusivity, another company may obtain FDA licensure and market a competing version of the reference product if the FDA approves a full de novo BLA, not an abbreviated BLA for a biosimilar product, for the competing product containing that applicant’s own preclinical data and data from adequate and well-controlled clinical trials to demonstrate the safety, purity and potency of its product.

The law is complex and is still being interpreted and implemented by the FDA. Any processes adopted by the FDA to implement the BPCIA could have a material adverse effect on the future commercial prospects for our biologic products. In addition, there has been discussion of whether Congress should reduce the 12-year reference product exclusivity period. Other aspects of the BPCIA, some of which may impact the BPCIA exclusivity provisions, have also been the subject of recent litigation. As a result, the ultimate implementation of the BPCIA is subject to significant uncertainty.

We believe that any of our drug candidates approved as a biologic product under a BLA should qualify for the 12-year period of exclusivity. However, there is a risk that this exclusivity could be shortened due to congressional action or otherwise, or that the FDA will not consider our drug candidates to be reference products for competing products, potentially creating the opportunity for generic competition sooner than anticipated. Moreover, the extent to which a biosimilar, once approved, will be substituted for any one of our reference products in a way that is similar to traditional generic substitution for non-biologic products is not yet clear, and will depend on a number of marketplace and regulatory factors that are still developing.

We may be unable to maintain the benefits associated with Orphan Drug Designation, including the potential for supplemental market exclusivity.

Birtamimab has been granted Orphan Drug Designation by both the FDA and EMA for the treatment of AL amyloidosis. In addition, we may seek Orphan Drug Designation for one or more of our current or future drug candidates. Regulatory authorities in some jurisdictions, including the United States and Europe, may designate drug products for relatively small patient populations as orphan drugs. Under the Orphan Drug Act, the FDA may grant orphan designation to a drug product intended to treat a rare disease or condition, defined as a disease or condition with a patient population of fewer than 200,000 in the United States. In the United States, Orphan Drug Designation entitles a party to financial incentives such as opportunities for grant funding towards clinical trial costs, tax advantages and user-fee waivers. Orphan Drug Designation does not convey any advantage in, or shorten the duration of, the regulatory review and licensure process.

If a drug product that has Orphan Drug Designation subsequently receives the first FDA approval or licensure for a particular active ingredient for the disease for which it has such designation, the drug product is entitled to orphan product exclusivity, which means that the FDA may not approve any other applications, including an NDA or BLA, to market the same drug product for the same indication for seven years, except in limited circumstances such as a showing of clinical superiority to the product with orphan drug exclusivity or if the FDA finds that the holder of the orphan drug exclusivity has not shown that it can assure the availability of sufficient quantities of the orphan drug to meet the needs of patients with the disease or condition for which the biological product was designated. As a result, even if one of our drug candidates receives orphan exclusivity, the FDA can still approve or license other drug products that have a different active ingredient for use in treating the same indication or disease. Further, the FDA can waive orphan exclusivity if we are unable to manufacture sufficient supply of our drug product.

A Fast Track designation by the FDA, even if granted for current or future drug candidates, may not lead to a faster development or regulatory review, licensure process and does not increase the likelihood that our drug candidates will receive marketing licensure.

Birtamimab has been granted Fast Track Designation by the FDA for the treatment of AL amyloidosis. In addition, we may seek Fast Track designation for one or more of our future drug candidates. If a drug candidate is intended for the treatment of a serious condition and demonstrates the potential to address an unmet medical need for this condition, the sponsor may apply for FDA Fast Track designation for a particular indication. We may seek Fast Track designation for our drug candidates, but there is no assurance that the FDA will grant this status to any of our drug candidates. The FDA has broad discretion

whether or not to grant Fast Track designation, and even if we consider a particular drug candidate to be eligible for this designation, there is no assurance that it will be granted by the FDA. Even if we do receive Fast Track designation, we may not experience a faster review or approval compared to other, non-expedited FDA procedures, and receiving a Fast Track designation does not provide assurance of ultimate FDA approval. In addition, the FDA may withdraw Fast Track designation if it believes that the designation is no longer supported by data from our applicable clinical development program. Marketing applications filed by sponsors of products granted Fast Track designation may qualify for priority review under FDA policies and procedures, but Fast Track designation does not assure any such review or ultimate marketing approval by the FDA.

We are subject to healthcare and other laws and regulations, including anti-bribery, anti-kickback, fraud and abuse, false claims, and physician payment transparency laws and regulations, which could expose us to criminal, civil and/or administrative sanctions and penalties; exclusion from governmental healthcare programs or reimbursements; contractual damages; and reputational harm.

Our operations and activities are directly, or indirectly through our service providers and collaborators, subject to numerous healthcare and other laws and regulations, including, without limitation, those relating to anti-bribery, anti-kickback, fraud and abuse, false claims, physician payment transparency, and health information privacy and security, in the U.S., the EU, and other countries and jurisdictions in which we conduct our business. These laws include:

•the U.S. Anti-Kickback Statute, which prohibits, among other things, persons from knowingly and willfully soliciting, receiving, offering or paying remuneration, directly or indirectly, in cash or in kind, to induce or reward, or in return for, either the referral of an individual for, or the purchase or recommendation of an item or service reimbursable under a federal healthcare program, such as the Medicare and Medicaid programs. A person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation;

•U.S. federal false claims laws, including the False Claims Act, which impose criminal and civil penalties, including civil whistleblower or qui tam actions, against individuals or entities for knowingly presenting, or causing to be presented, claims for payment from Medicare, Medicaid, or other third-party payers that are false or fraudulent or making a false statement to avoid, decrease or conceal an obligation to pay money to the federal government. In addition, the government may assert that a claim including items and services resulting from a violation of the U.S. federal Anti-Kickback Statute constitutes a false or fraudulent claim for purposes of the False Claims Act;

•the U.S. Health Insurance Portability and Accountability Act of 1996 (“HIPAA”), which imposes criminal and civil liability for executing a scheme to defraud any healthcare benefit program and making false statements in connection with the delivery of or payment for healthcare benefits, items or services. Similar to the U.S. federal Anti-Kickback Statute, a person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation;

•the U.S. Physician Payment Sunshine Act, which requires applicable manufacturers of drugs, devices, biologics and medical supplies for which payment is available under Medicare, Medicaid or the Children’s Health Insurance Program, with specific exceptions, to report annually to the Centers for Medicare & Medicaid Services (“CMS”) information related to “payments or other transfers of value” made to physicians (defined to include doctors, dentists, optometrists, podiatrists and chiropractors) and teaching hospitals and applicable manufacturers and applicable group purchasing organizations to report annually to CMS ownership and investment interests held by the physicians (as defined by statute) and their immediate family members. Effective January 1, 2022, these reporting obligations will extend to include transfers of value made during the previous year to physician assistants, nurse practitioners, clinical nurse specialists, anesthesiologist assistants, certified registered nurse anesthetists, and certified nurse midwives;

•state laws and regulations that apply to sales or marketing arrangements; apply to healthcare items or services reimbursed by non-governmental third-party payers, including private insurers; require pharmaceutical companies to comply with the pharmaceutical industry’s voluntary compliance guidelines; that restrict payments that may be made to healthcare providers; require drug manufacturers to report information related to payments and other transfers of value to physicians and other healthcare providers or marketing expenditures; and

•similar and other laws and regulations in the U.S. (federal, state and local), in the EU (including member countries), and other countries and jurisdictions.

On September 4, 2018, we received a subpoena from the U.S. Department of Justice requesting the production of documents relating to our NEOD001 development program. We completed the production of documents in July 2019. Since that time, the Department of Justice has not requested that we provide any additional information.

We cannot predict the outcome of this matter or whether any government agency will take further action. If further action is taken, it could divert the attention of management and require the devotion of a substantial amount of time and resources.

Ensuring our compliance with applicable laws and regulations involves substantial costs, and it is possible that governmental authorities or third parties will assert that our business practices fail to comply with these laws and regulations. If our actions are found to be in violation of any laws and regulations, we may be subject to significant civil, criminal, and administrative damages, penalties, and fines, as well as exclusion from participation in government healthcare programs, curtailment or restructuring of our operations, and reputational harm, any of which could have a material adverse effect on our business, financial condition, or results of operations.

If a successful product liability or clinical trial claim or series of claims is brought against us for uninsured liabilities or in excess of insured liabilities, we could incur substantial liability.

The use of our drug candidates in clinical trials and the sale of any products for which we obtain marketing approval will expose us to the risk of product liability and clinical trial liability claims. Product liability claims might be brought against us by consumers, healthcare providers, or others selling or otherwise coming into contact with our products. Clinical trial liability claims may be filed against us for damages suffered by clinical trial subjects or their families. If we cannot successfully defend ourselves against product liability claims, we could incur substantial liabilities. In addition, regardless of merit or eventual outcome, product liability claims may result in:

•decreased demand for any approved drug candidates;

•impairment of our business reputation;

•withdrawal of clinical trial participants;

•costs of related litigation;

•distraction of management’s attention;

•substantial monetary awards to patients or other claimants;

•loss of revenues; and

•the inability to successfully commercialize any approved drug candidates.

We currently have clinical trial liability insurance coverage for all of our clinical trials. However, our insurance coverage may not be sufficient to reimburse us for any expenses or losses we may suffer. Moreover, insurance coverage is becoming increasingly expensive, and, in the future, we may not be able to maintain insurance coverage at a reasonable cost or in sufficient amounts to protect us against losses due to liability. If and when we obtain marketing approval for any of our drug candidates, we intend to expand our insurance coverage to include the sale of commercial products; however, we may be unable to obtain this product liability insurance on commercially reasonable terms. On occasion, large judgments have been awarded in class action lawsuits based on drugs that had unanticipated side effects. A successful product liability claim or series of claims brought against us could cause our ordinary share price to decline and, if judgments exceed our insurance coverage, could decrease our cash and adversely affect our business.

Risks Related to Our Dependence on Third Parties

We rely on third parties to conduct our clinical trials, and those third parties may not perform satisfactorily, including failing to meet established deadlines for the completion of any such clinical trials.

We do not have the ability to independently conduct clinical trials for our drug candidates, and we rely on third parties, such as consultants, contract research organizations, medical institutions, and clinical investigators to assist us with these activities. Our reliance on these third parties for clinical development activities results in reduced control over these activities. Furthermore, these third parties may also have relationships with other entities, some of which may be our competitors. Although we have and will enter into agreements with these third parties, we will be responsible for confirming that our clinical trials are conducted in accordance with their general investigational plans and protocols. Moreover, the FDA, the EMA, and other comparable regulatory authorities require us to comply with regulations and standards, commonly referred to as cGCPs, for conducting, recording, and reporting the results of clinical trials to assure that data and reported results are credible and accurate and that the trial participants are adequately protected. Our reliance on third parties does not relieve us of these responsibilities and requirements. If we or any of our third-party contractors fail to comply with applicable cGCPs, the clinical data generated in our clinical trials may be deemed unreliable and the FDA, the EMA, or other comparable regulatory authorities may require us to perform additional clinical trials before approving our marketing applications. We cannot assure you that upon inspection by a given regulatory authority, such regulatory authority will determine that any of our clinical trials complies with cGCP regulations. In addition, our clinical trials must be conducted with product produced under cGMPs. Our

failure to comply with these regulations may require us to repeat clinical trials, which would delay the regulatory approval process.

To date, we believe our consultants, contract research organizations, and other third parties with which we are working have performed well; however, if these third parties do not successfully carry out their contractual duties, meet expected deadlines, or comply with applicable regulations, we may be required to replace them. Although we believe that there are a number of other third-party contractors we could engage to continue these activities, we may not be able to enter into arrangements with alternative third-party contractors or to do so on commercially reasonable terms, which may result in a delay of our planned clinical trials. Accordingly, we may be delayed in obtaining regulatory approvals for our drug candidates and may be delayed in our efforts to successfully develop our drug candidates.

In addition, our third-party contractors are not our employees, and except for remedies available to us under our agreements with such third-party contractors, we cannot control whether or not they devote sufficient time and resources to our ongoing clinical and nonclinical programs. If third-party contractors do not successfully carry out their contractual duties or obligations or meet expected deadlines, if they need to be replaced or if the quality or accuracy of the clinical data they obtain is compromised due to the failure to adhere to our clinical protocols, regulatory requirements or for other reasons, our clinical trials may be extended, delayed or terminated and we may not be able to obtain regulatory approval for or successfully commercialize our drug candidates. As a result, our results of operations and the commercial prospects for our drug candidates would be harmed, our costs could increase and our ability to generate revenues could be delayed.

If we do not establish additional strategic collaborations, we may have to alter our research, development, and/or commercialization plans.

Research, development, and potential commercialization of our drug candidates will require substantial additional cash to fund expenses. Our strategy includes potentially collaborating with additional leading pharmaceutical and biotechnology companies to assist us in furthering research, development, and/or potential commercialization of some of our drug candidates in some or all geographies. It may be difficult to enter into one or more of such collaborations in the future. We face significant competition in seeking appropriate collaborators and these collaborations are complex and time-consuming to negotiate and document. We may not be able to negotiate collaborations on acceptable terms, or at all, in which case we may have to curtail the development of a particular drug candidate, reduce or delay its development program or one or more of our other development programs, delay its potential commercialization or increase our expenditures and undertake development or commercialization activities at our own expense. If we elect to increase our expenditures to fund development or commercialization activities on our own, we will need to obtain additional capital, which may not be available to us on acceptable terms, or at all. If we do not have sufficient funds, we will not be able to bring our drug candidates to market and generate product revenue.

We have no manufacturing capacity and depend on third-party manufacturers to supply us with nonclinical and clinical trial supplies of all of our drug candidates, and we will depend on third-party manufacturers to supply us with any drug product for commercial sale if we obtain marketing approval from the FDA, the EMA, or any other comparable regulatory authority for any of our drug candidates.

We do not own or operate facilities for the manufacture, packaging, labeling, storage, testing, or distribution of nonclinical or clinical supplies of any of our drug candidates. We instead contract with and rely on third parties to manufacture, package, label, store, test, and distribute nonclinical and clinical supplies of our drug candidates, and we plan to continue to do so for the foreseeable future. We also rely on third-party consultants to assist us with managing these third-parties and with our manufacturing strategy. If any of these third-parties fail to perform these activities for us, nonclinical or clinical development of our drug candidates could be delayed, which could have an adverse effect on our business, financial condition, results of operations, and/or growth prospects.

If the FDA, the EMA, or any other comparable regulatory authority approves any of our drug candidates for commercial sale, we expect to continue to rely, at least initially, on third-parties to manufacture, package, label, store, test, and distribute commercial supplies of such approved drug product. Significant scale-up of manufacturing may require additional comparability validation studies, which the FDA, the EMA, or other comparable regulatory authorities must review and approve. Our third-party manufacturers might not be able to successfully establish such comparability or increase their manufacturing capacity in a timely or economic manner, or at all. If our third-party manufacturers are unable to successfully establish comparability or increase their manufacturing capacity for any drug product, and we are unable to timely establish our own manufacturing capabilities, the commercial launch of that drug candidate could be delayed or there could be a shortage in supply, which could have an adverse effect on our business, financial condition, results of operations, and/or growth prospects.

Our third-party manufacturers’ facilities could be damaged by fire, power interruption, information system failure, natural disaster or other similar event, which could cause a delay or shortage in supplies of our drug candidates, which could have an adverse effect on our business, financial condition, results of operations, and/or growth prospects.

Our drug candidates require, and any future drug product will require, precise, high quality manufacturing, packaging, labeling, storage, and testing that meet stringent cGMP, other regulatory requirements and other standards. Our third-party manufacturers are subject to ongoing periodic and unannounced inspections by the FDA, the EMA, and other comparable regulatory authorities to ensure compliance with these cGMPs, other regulatory requirements and other standards. We do not have control over, and are dependent upon, our third-party manufacturers’ compliance with these cGMPs, regulations and standards. Any failure by a third-party manufacturer to comply with these cGMPs, regulations or standards or that compromises the safety of any of our drug candidates or any drug product could cause a delay or suspension of production of nonclinical or clinical supplies of our drug candidates or commercial supplies of drug product, cause a delay or suspension of nonclinical or clinical development, product approval and/or commercialization of our drug candidates or drug product, result in seizure or recall of clinical or commercial supplies, result in fines and civil penalties, result in liability for any patient injury or death or otherwise increase our costs, any of which could have an adverse effect on our business, financial condition, results of operations, and/or growth prospects. If a third-party manufacturer cannot or fails to perform its contractual commitments, does not have sufficient capacity to meet our nonclinical, clinical or eventual commercial requirements or fails to meet cGMPs, regulations or other standards, we may be required to replace it or qualify an additional third-party manufacturer. Although we believe there are a number of potential alternative manufacturers, the number of manufacturers with the necessary manufacturing and regulatory expertise and facilities to manufacture biologics like our antibodies is limited. In addition, we could incur significant additional costs and delays in identifying and qualifying any new third-party manufacturer, due to the technology transfer to such new manufacturer and because the FDA, the EMA, and other comparable regulatory authorities must approve any new manufacturer prior to manufacturing our drug candidates. Such approval would require successful technology transfer, comparability and other testing and compliance inspections. Transferring manufacturing to a new manufacturer could therefore interrupt supply, delay our clinical trials and any commercial launch, and/or increase our costs for our drug candidates, any of which could have an adverse effect on our business, financial condition, results of operations, and/or growth prospects.

Rentschler Biopharma SE (“Rentschler”) and Catalent Pharma Solutions, LLC (“Catalent”) are our third-party manufacturers of clinical supplies of birtamimab. We are dependent on Rentschler and Catalent to manufacture these clinical supplies.

Roche, with whom we are collaborating on development of prasinezumab, manufactured clinical supplies for the Phase 2 and Phase 2b clinical trials for prasinezumab and is expected to do so for any subsequent clinical trials of prasinezumab. We are dependent on Roche to continue to manufacture these clinical supplies.

We are dependent on Novo Nordisk, and its third party manufacturers if applicable, to manufacture clinical supplies of PRX004 .

Catalent and Berkshire Sterile Manufacturing, LLC (“Berkshire”) are our third-party manufacturers of clinical supplies of PRX005. We are dependent on Catalent and Berkshire to manufacture these clinical supplies.

Catalent is our third-party manufacturer of clinical supplies of our drug candidate PRX012. We are dependent on Catalent to manufacture these clinical supplies.

In July 2021, the Company sold the equity interests of a subsidiary that owns and has exclusive licenses to intellectual property rights and other assets pertaining to the investigational humanized monoclonal antibody known as PRX004, and we might not realize the anticipated benefits of such transaction.

On July 8, 2021, the Company, together with its wholly owned subsidiary, Prothena Biosciences Limited (“PBL”), entered into a Share Purchase Agreement with Novo Nordisk and NNRE (together with Novo Nordisk, “Buyer”), pursuant to which PBL sold and transferred to NNRE, all issued and outstanding ordinary shares of Neotope Neuroscience Limited, a wholly owned subsidiary of PBL, for an aggregate purchase price of up to $1.23 billion. The aggregate purchase price consists of an upfront payment of $60 million in cash, subject to customary purchase price adjustments, and an aggregate of $1.17 billion in cash, payable on Buyer’s achievement of certain development, commercialization and net sales-based milestones. There can be no assurance that such milestones will be met. If we do not receive milestone payments as a result of the transaction in anticipated amounts or at all, we may need to seek additional sources of capital to pursue further research, development, and/or commercialization of our drug candidates, and this could have a material adverse effect on our business, financial condition, results of operations, and/or growth prospects.

We depend on third-party suppliers for key raw materials used in our manufacturing processes, and the loss of these third-party suppliers or their inability to supply us with adequate raw materials could harm our business.

We rely on third-party suppliers for the raw materials required for the production of our drug candidates. Our dependence on these third-party suppliers and the challenges we may face in obtaining adequate supplies of raw materials involve several risks, including limited control over pricing, availability, quality, and delivery schedules. We cannot be certain that our suppliers will continue to provide us with the quantities of these raw materials that we require or satisfy our anticipated specifications and quality requirements. Any supply interruption in limited or sole sourced raw materials could materially harm our ability to manufacture our products until a new source of supply, if any, could be identified and qualified. Although we believe there are currently several other suppliers of these raw materials, we may be unable to find a sufficient alternative supply channel in a reasonable time or on commercially reasonable terms. Any performance failure on the part of our suppliers could delay the development and potential commercialization of our drug candidates, including limiting supplies necessary for clinical trials and regulatory approvals, which would have a material adverse effect on our business.

Risks Related to Our Intellectual Property

If we are unable to adequately protect or enforce the intellectual property relating to our drug candidates our ability to successfully commercialize our drug candidates will be harmed.

Our success depends in part on our ability to obtain patent protection both in the U.S. and in other countries for our drug candidates. Our ability to protect our drug candidates from unauthorized or infringing use by third parties depends in substantial part on our ability to obtain and maintain valid and enforceable patents. Due to evolving legal standards relating to the patentability, validity and enforceability of patents covering pharmaceutical inventions and the scope of claims made under these patents, our ability to obtain, maintain and enforce patents is uncertain and involves complex legal, factual and scientific questions. Accordingly, rights under any issued patents may not provide us with sufficient protection for our drug candidates or provide sufficient protection to afford us a commercial advantage against competitive products or processes. Additionally, our ability to obtain patent protection for our drug candidates also depends on our collaborators, partners, contractors, and employees involved in the generation of intellectual property to carry out their contractual duties, including those to assign or license relevant intellectual property rights developed on our behalf to us.

In addition, the strength of patents in the biotechnology and pharmaceutical field can be uncertain, and evaluating the scope of such patents involves complex legal, factual, and scientific analyses and has in recent years been the subject of much litigation, resulting in court decisions, including Supreme Court decisions, which have increased uncertainties as to the ability to enforce patent rights in the future. We cannot guarantee that any patents will issue from any pending or future patent applications owned by or licensed to us or our affiliates. Even if patents have issued or will issue, we cannot guarantee that the claims of these patents are or will be valid or enforceable or will provide us with any significant protection against competitive products or otherwise be commercially valuable to us. Patent applications in the U.S. are maintained in confidence for up to 18 months after their filing. In some cases, however, patent applications remain confidential in the U.S. Patent and Trademark Office (the “USPTO”) for the entire time prior to issuance as a U.S. patent. Similarly, publication of discoveries in the scientific or patent literature often lags behind actual discoveries. Consequently, we cannot be certain that we or our licensors or co-owners were the first to invent, or the first to file patent applications on, our drug candidates or their use as drugs. In the event that a third party has also filed a U.S. patent application relating to our drug candidates or a similar invention, we may have to participate in interference or derivation proceedings declared by the USPTO to determine priority of invention in the U.S. The costs of these proceedings could be substantial and it is possible that our efforts would be unsuccessful, resulting in a loss of our U.S. patent position. Furthermore, we may not have identified all U.S. and non-U.S. patents or published applications that affect our business either by blocking our ability to commercialize our drugs or by covering similar technologies. Composition-of-matter patents on the biological or chemical active pharmaceutical ingredient are generally considered to be the strongest form of intellectual property protection for pharmaceutical products, as such patents provide protection without regard to any method of use. We cannot be certain that the claims in our patent applications covering composition-of-matter of our drug candidates will be considered patentable by the USPTO and courts in the U.S. or by the patent offices and courts in other countries, nor can we be certain that the claims in our issued composition-of-matter patents will not be found invalid or unenforceable if challenged. Method-of-use patents protect the use of a product for the specified method. This type of patent does not prevent a competitor from making and marketing a product that is identical to our product for an indication that is outside the scope of the patented method. Moreover, even if competitors do not actively promote their product for our targeted indications, physicians may prescribe these products “off-label.” Although off-label prescriptions may infringe or contribute to the infringement of method-of-use patents, the practice is common and such infringement is difficult to prevent or prosecute.

We cannot guarantee that any of our patent searches or analyses, including the identification of relevant patents, the scope of patent claims or the expiration of relevant patents, are complete or thorough, nor can we be certain that we have identified each and every third-party patent and pending application in the United States and abroad that is relevant to or necessary for the commercialization of our drug candidates in any jurisdiction. The scope of a patent claim is determined by an interpretation of

the law, the written disclosure in a patent and the patent’s prosecution history. Our interpretation of the relevance or the scope of a patent or a pending application may be incorrect, which may negatively impact our ability to market our products. We may incorrectly determine that our products are not covered by a third-party patent or may incorrectly predict whether a third-party’s pending application will issue with claims of relevant scope. Our determination of the expiration date of any patent in the United States or abroad that we consider relevant may be incorrect, which may negatively impact our ability to develop and market our drug candidates. Our failure to identify and correctly interpret relevant patents may negatively impact our ability to develop and market our products.

We may be subject to a third-party preissuance submission of prior art to the USPTO and foreign patent agencies, or become involved in opposition, derivation, reexamination, inter partes review, post-grant review, or other patent office proceedings or litigation, in the U.S. or elsewhere, challenging our patent rights or the patent rights of others. An adverse determination in any such submission, proceeding or litigation could result in loss of exclusivity or in patent claims being narrowed, invalidated, or held unenforceable, in whole or in part, which could limit our ability to stop others from using or commercializing similar or identical technology and products, or limit the duration of the patent protection of our technology and products. In addition, given the amount of time required for the development, testing and regulatory review of new drug candidates, patents protecting such candidates might expire before or shortly after such candidates are commercialized. Any failure to obtain or maintain patent protection with respect to our drug candidates could have a material adverse effect on our business, financial condition, results of operations, and/or growth prospects.

Changes in U.S. patent law could diminish the value of patents in general, thereby impairing our ability to protect our products.

As is the case with other biopharmaceutical companies, our success is heavily dependent on intellectual property, particularly patents. Obtaining and enforcing patents in the biopharmaceutical industry involves both technological and legal complexity and is costly, time-consuming, and inherently uncertain. Changes in either the patent laws or interpretation of the patent laws in the United States could increase the uncertainties and costs, and may diminish our ability to protect our inventions, obtain, maintain, and enforce our intellectual property rights and, more generally, could affect the value of our intellectual property or narrow the scope of our owned and licensed patents. Recent patent reform legislation in the United States and other countries, including the Leahy-Smith America Invents Act, or the Leahy-Smith Act, signed into law on September 16, 2011, could increase those uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents. The Leahy-Smith Act includes a number of significant changes to U.S. patent law. These include provisions that affect the way patent applications are prosecuted, redefine prior art and provide more efficient and cost-effective avenues for competitors to challenge the validity of patents. These include allowing third-party submission of prior art to the USPTO during patent prosecution and additional procedures to attack the validity of a patent by USPTO administered post-grant proceedings, including post-grant review, inter partes review, and derivation proceedings. After March 2013, under the Leahy-Smith Act, the United States transitioned to a first inventor to file system in which, assuming that the other statutory requirements are met, the first inventor to file a patent application will be entitled to the patent on an invention regardless of whether a third-party was the first to invent the claimed invention. A third party that files a patent application in the USPTO after March 2013, but before we file an application covering the same invention, could therefore be awarded a patent covering an invention of ours even if we had made the invention before it was made by such third party. This will require us to be cognizant going forward of the time from invention to filing of a patent application. Since patent applications in the United States and most other countries are confidential for a period of time after filing or until issuance, we cannot be certain that we or our licensors were the first to either (i) file any patent application related to our drug candidates and other proprietary technologies we may develop or (ii) invent any of the inventions claimed in our or our licensor’s patents or patent applications. Even where we have a valid and enforceable patent, we may not be able to exclude others from practicing the claimed invention where the other party can show that they used the invention in commerce before our filing date or the other party benefits from a compulsory license. However, the Leahy-Smith Act and its implementation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents, all of which could have a material adverse effect on our business, financial condition, results of operations, and/or growth prospects.

Recent U.S. Supreme Court rulings have narrowed the scope of patent protection available in certain circumstances and weakened the rights of patent owners in certain situations. In addition to increasing uncertainty with regard to our ability to obtain patents in the future, this combination of events has created uncertainty with respect to the value of patents once obtained. Depending on decisions by Congress, the federal courts, the USPTO and the relevant law-making bodies in other countries, the laws and regulations governing patents could change in unpredictable ways that would weaken our ability to obtain new patents or to enforce our existing patents and patents that we might obtain in the future. We cannot predict how future decisions by Congress, the federal courts or the USPTO may impact the value of our patents.

Obtaining and maintaining our patent protection depends on compliance with various procedural, document submission, fee payment, and other requirements imposed by governmental patent agencies, and our patent protection could be reduced or eliminated for non-compliance with these requirements.

Periodic maintenance fees on any issued patent are due to be paid to the USPTO and foreign patent agencies in several stages over the lifetime of the patent. The USPTO and various foreign governmental patent agencies require compliance with a number of procedural, documentary, fee payment, and other similar provisions during the patent application process. Although an inadvertent lapse, including due to the effect of the COVID-19 pandemic on us or our patent maintenance vendors, can in many cases be cured by payment of a late fee or by other means in accordance with the applicable rules, there are situations in which noncompliance can result in abandonment or lapse of the patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. Noncompliance events that could result in abandonment or lapse of a patent or patent application or invalidity of an issued patent include failure to respond to official actions within prescribed time limits, non-payment of fees, failure to properly legalize and submit formal documents, and failure to submit certain prior art. In any such event, our competitors might be able to enter the market, which would have a material adverse effect on our business.

The lives of our patents may not be sufficient to effectively protect our products and business.

Patents have a limited lifespan. In the United States, if all maintenance fees are paid timely, the natural expiration of a patent is generally 20 years after its first effective filing date. Although various extensions may be available, the life of a patent, and the protection it affords, is limited. Given the amount of time required for the development, testing, and regulatory review of new drug candidates, patents protecting such candidates might expire before or shortly after such drug candidates are commercialized. Even if patents covering our drug candidates are obtained, once a patent covering a drug candidate has expired, we may be open to competition, including biosimilar or generic medications. As a result, our patent portfolio may not provide us with sufficient rights to exclude others from commercializing drug candidates similar or identical to ours. Our patents issued as of December 31, 2020, are anticipated to expire on dates ranging from 2023 to 2040, subject to any patent extensions that may be available for such patents. If patents are issued on our patent applications pending as of December 31, 2020, the resulting patents are projected to expire on dates ranging from 2025 to 2041. In addition, although upon issuance in the United States a patent’s life can be increased based on certain delays caused by the USPTO, this increase can be reduced or eliminated based on certain delays caused by the patent applicant during patent prosecution. A patent term extension based on regulatory delay may be available in the United States. However, only a single patent can be extended for each first regulatory review period for a product, and any patent can be extended only once, for a single product. Moreover, the scope of protection during the period of the patent term extension does not extend to the full scope of the claim, but instead only to the scope of the product as approved. Laws governing analogous patent term extensions in foreign jurisdictions vary widely, as do laws governing the ability to obtain multiple patents from a single patent family. Additionally, we may not receive an extension if we fail to exercise due diligence during the testing phase or regulatory review process, apply within applicable deadlines, fail to apply prior to expiration of relevant patents or otherwise fail to satisfy applicable requirements. If we are unable to obtain patent term extension or restoration, or the term of any such extension is less than we request, the period during which we will have the right to exclusively market our product will be shortened and our competitors may obtain approval of competing products following our patent expiration and may take advantage of our investment in development and clinical trials by referencing our clinical and preclinical data to launch their product earlier than might otherwise be the case, and our revenue could be reduced, possibly materially. If we do not have sufficient patent life to protect our products, our business and results of operations will be adversely affected.

We may be subject to claims challenging the inventorship or ownership of our patents and other intellectual property.

We may be subject to claims that former employees, collaborators, or other third parties have an interest in our patents or other intellectual property as an inventor or co-inventor. The failure to name the proper inventors on a patent application can result in the patents issuing thereon being unenforceable. Inventorship disputes may arise from conflicting views regarding the contributions of different individuals named as inventors, the effects of foreign laws where foreign nationals are involved in the development of the subject matter of the patent, conflicting obligations of third parties involved in developing our drug candidates or as a result of questions regarding co-ownership of potential joint inventions. For example, we may have inventorship disputes arise from conflicting obligations of consultants or others who are involved in developing our drug candidates. Alternatively, or additionally, we may enter into agreements to clarify the scope of our rights in such intellectual property. Litigation may be necessary to defend against these and other claims challenging inventorship. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights, such as exclusive ownership of, or right to use, valuable intellectual property. Such an outcome could have a material adverse effect on our business. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

We or our licensors may have relied on third-party consultants or collaborators or on funds from third parties, such as the U.S. government, such that we or our licensors are not the sole and exclusive owners of the patents we in-licensed. If other third

parties have ownership rights or other rights to our patents, including in-licensed patents, they may be able to license such patents to our competitors, and our competitors could market competing products and technology. This could have a material adverse effect on our competitive position, business, financial conditions, results of operations, and prospects.

In addition, while it is our policy to require our employees and contractors who may be involved in the conception or development of intellectual property to execute agreements assigning such intellectual property to us, we may be unsuccessful in executing such an agreement with each party who, in fact, conceives or develops intellectual property that we regard as our own. The assignment of intellectual property rights may not be self-executing, or the assignment agreements may be breached, and we may be forced to bring claims against third parties, or defend claims that they may bring against us, to determine the ownership of what we regard as our intellectual property. Such claims could have a material adverse effect on our business, financial condition, results of operations, and/or growth prospects.

We may not be able to protect our intellectual property rights throughout the world.

Patents are of national or regional effect, and filing, prosecuting, maintaining, and defending patents on drug candidates in all countries throughout the world would be prohibitively expensive, and our intellectual property rights in some countries outside the United States can have a different scope and strength than do those in the United States. In addition, the laws of some foreign countries, particularly certain developing countries, do not protect intellectual property rights to the same extent as federal and state laws in the United States. Consequently, we may not be able to prevent third parties from practicing our inventions in all countries outside the United States, or from selling or importing products made using our inventions in and into the United States or other jurisdictions. Competitors may use our technologies in jurisdictions where we have not obtained patent protection to develop their own products and further, may export otherwise infringing products to territories where we have patent protection, but enforcement rights are not as strong as those in the United States. These products may compete with our products and our patents or other intellectual property rights may not be effective or adequate to prevent them from competing.

We license patent rights from third-party owners. Such licenses may be subject to early termination if we fail to comply with our obligations in our licenses with third parties, which could result in the loss of rights or technology that are material to our business.

We are a party to licenses that give us rights to third-party intellectual property or technology that is necessary or useful for our business, and we may enter into additional licenses in the future. Under these license agreements we are obligated to pay the licensor fees, which may include annual license fees, milestone payments, royalties, a percentage of revenues associated with the licensed technology and a percentage of sublicensing revenue. In addition, under certain of such agreements, we are required to diligently pursue the development of products using the licensed technology. If we fail to comply with these obligations, including due to the impact of the COVID-19 pandemic on our business operations or our use of the intellectual property licensed to us in an unauthorized manner, and fail to cure our breach within a specified period of time, the licensor may have the right to terminate the applicable license, in which event we could lose valuable rights and technology that are material to our business, harming our ability to develop, manufacture, and/or commercialize our platform or drug candidates.

In addition, the agreements under which we license intellectual property or technology to or from third parties are complex, and certain provisions in such agreements may be susceptible to multiple interpretations. The resolution of any contract interpretation disagreement that may arise could narrow what we believe to be the scope of our rights to the relevant intellectual property or technology or increase what we believe to be our financial or other obligations under the relevant agreement, either of which could have a material adverse effect on our business, financial condition, results of operations, and/or growth prospects. Moreover, if disputes over intellectual property that we have licensed prevent or impair our ability to maintain our current licensing arrangements on commercially acceptable terms, we may be unable to successfully develop and commercialize the affected drug candidates. Our business also would suffer if any current or future licensors fail to abide by the terms of the license, if the licensors fail to enforce licensed patents against infringing third parties, if the licensed patents or other rights are found to be invalid or unenforceable, or if we are unable to enter into necessary licenses on acceptable terms. Moreover, our licensors may own or control intellectual property that has not been licensed to us and, as a result, we may be subject to claims, regardless of their merit, that we are infringing or otherwise violating the licensor’s rights.

In addition, while we cannot currently determine the amount of the royalty obligations we would be required to pay on sales of future products, if any, the amounts may be significant. The amount of our future royalty obligations will depend on the technology and intellectual property we use in products that we successfully develop and commercialize, if any. Therefore, even if we successfully develop and commercialize products, we may be unable to achieve or maintain profitability.

If we are unable to successfully obtain rights to required third-party intellectual property rights or maintain the existing intellectual property rights we have, we may have to abandon development of the relevant research programs or drug candidates and our business, financial condition, results of operations, and/or growth prospects could suffer.

Licensing of intellectual property is of critical importance to our business and involves complex legal, business and scientific issues and is complicated by the rapid pace of scientific discovery in our industry. Disputes may also arise between us and our licensors regarding intellectual property subject to a license agreement, including those relating to:

•the scope of rights granted under the license agreement and other interpretation-related issues;

•whether and the extent to which our technology and processes infringe on intellectual property of the licensor that is not subject to the license agreement;

•our right to sublicense patent and other rights to third parties under collaborative development relationships;

•whether we are complying with our diligence obligations with respect to the use of the licensed technology in relation to our development and commercialization of our drug candidates, and what activities satisfy those diligence obligations;

•the priority of invention of patented technology;

•the amount and timing of payments owed under license agreements; and

•the allocation of ownership of inventions and know-how resulting from the joint creation or use of intellectual property by our licensors and by us and our partners.

If disputes over intellectual property that we have licensed prevent or impair our ability to maintain our current licensing arrangements on acceptable terms, we may be unable to successfully develop and commercialize the affected drug candidates. We are generally also subject to all of the same risks with respect to protection of intellectual property that we license as we are for intellectual property that we own, which are described below. If we or our licensors fail to adequately protect this intellectual property, our ability to commercialize our products could suffer.

We depend, in part, on our licensors to file, prosecute, maintain, defend, and enforce patents and patent applications that are material to our business.

If the licensor retains control of prosecution of the patents and patent applications licensed to us, we may have limited or no control over the manner in which the licensor chooses to prosecute or maintain its patents and patent applications and have limited or no right to continue to prosecute any patents or patent applications that the licensor elects to abandon. If our licensors or any future licensees having rights to file, prosecute, maintain, and defend our patent rights fail to conduct these activities for patents or patent applications covering any of our drug candidates, including due to the impact of the COVID-19 pandemic on our licensors’ business operations, our ability to develop and commercialize those drug candidates may be adversely affected and we may not be able to prevent competitors from making, using, or selling competing products. We cannot be certain that such activities by our licensors have been or will be conducted in compliance with applicable laws and regulations or will result in valid and enforceable patents or other intellectual property rights. Pursuant to the terms of the license agreements with some of our licensors, the licensors may have the right to control enforcement of our licensed patents or defense of any claims asserting the invalidity of these patents and, even if we are permitted to pursue such enforcement or defense, we cannot ensure the cooperation of our licensors. We cannot be certain that our licensors will allocate sufficient resources or prioritize their or our enforcement of such patents or defense of such claims to protect our interests in the licensed patents. Even if we are not a party to these legal actions, an adverse outcome could harm our business because it might prevent us from continuing to license intellectual property that we may need to operate our business. In addition, even when we have the right to control patent prosecution of licensed patents and patent applications, enforcement of licensed patents, or defense of claims asserting the invalidity of those patents, we may still be adversely affected or prejudiced by actions or inactions of our licensors and their counsel that took place prior to or after our assuming control. In the event we breach any of our obligations related to such prosecution, we may incur significant liability to our licensing partners.

We may wish to form collaborations in the future with respect to our drug candidates, but may not be able to do so or to realize the potential benefits of such transactions, which may cause us to alter or delay our development and commercialization plans.

Our drug candidates may also require specific components to work effectively and efficiently, and rights to those components may be held by others. We may be unable to in-license any compositions, methods of use, processes or other third party intellectual property rights from third parties that we identify. We may fail to obtain any of these licenses at a reasonable cost or on reasonable terms, which would harm our business. If we fail to obtain licenses to necessary third-party intellectual property rights, we may need to cease use of the compositions or methods covered by such third-party intellectual property rights and may need to seek to develop alternative approaches that do not infringe on such intellectual property rights which may entail additional costs and development delays, even if we were able to develop such alternatives, which may not be feasible. Even if we are able to obtain a license, it may be non-exclusive, thereby giving our competitors access to the same

technologies licensed to us. In that event, we may be required to expend significant time and resources to develop or license replacement technology. Any delays in entering into new collaborations or strategic partnership agreements related to our drug candidates could delay the development and commercialization of our drug candidates in certain geographies, which could harm our business prospects, financial condition, and results of operations.

The licensing and acquisition of third-party intellectual property rights is a competitive practice, and companies that may be more established, or have greater resources than we do, may also be pursuing strategies to license or acquire third-party intellectual property rights that we may consider necessary or attractive in order to commercialize our drug candidates. More established companies may have a competitive advantage over us due to their larger size and cash resources or greater clinical development and commercialization capabilities. There can be no assurance that we will be able to successfully complete such negotiations and ultimately acquire the rights to the intellectual property surrounding the additional drug candidates that we may seek to acquire.

Moreover, some of our owned and in-licensed patents or patent applications or future patents are or may be co-owned with third parties. If we are unable to obtain an exclusive license to any such third-party co-owners’ interest in such patents or patent applications, such co-owners may be able to license their rights to other third parties, including our competitors, and our competitors could market competing products and technology. In addition, we may need the cooperation of any such co-owners of our patents in order to enforce such patents against third parties, and such cooperation may not be provided to us. Furthermore, our owned and in-licensed patents may be subject to a reservation of rights by one or more third parties. Any of the foregoing could have a material adverse effect on our competitive position, business, financial conditions, results of operations and prospects.

Litigation regarding patents, patent applications, and other proprietary rights may be expensive and time consuming. If we are involved in such litigation, it could cause delays in bringing drug candidates to market and harm our ability to operate.

Our success will depend in part on our ability to operate without infringing the proprietary rights of third parties. Although we are not currently aware of any litigation or other proceedings or third-party claims of intellectual property infringement related to our drug candidates, the pharmaceutical industry is characterized by extensive litigation regarding patents and other intellectual property rights, as well as administrative proceedings for challenging patents, including interference, derivation, inter partes review, post-grant review, and reexamination proceedings before the USPTO, or oppositions and other comparable proceedings in foreign jurisdictions , as well as administrative proceedings for challenging patents, including interference, derivation, inter partes review, post-grant review, and reexamination proceedings before the USPTO, or oppositions and other comparable proceedings in foreign jurisdictions. Other parties may hold or obtain patents in the future and allege that the use of our technologies infringes these patent claims or that we are employing their proprietary technology without authorization. Furthermore, patent reform and changes to patent laws add uncertainty to the possibility of challenge to our patents in the future. We cannot assure you that our drug candidates and other proprietary technologies we may develop will not infringe existing or future patents owned by third parties.

In addition, third parties may challenge our existing or future patents. Competitors may also infringe our patents or other intellectual property or the intellectual property of our licensors. To cease such infringement or unauthorized use, we may be required to file patent infringement claims, which can be expensive and time-consuming and divert the time and attention of our management and scientific personnel. Proceedings involving our patents or patent applications or those of others could result in adverse decisions regarding:

•the patentability of our inventions relating to our drug candidates; and/or

•the enforceability, validity or scope of protection offered by our patents relating to our drug candidates; and/or

•findings that our drug candidates, products, or activities infringe third party patents or other intellectual property rights.

Litigation or other legal proceedings relating to intellectual property claims, with or without merit, is unpredictable and generally expensive and time consuming and, even if resolved in our favor, is likely to divert significant resources from our core business including distracting our technical and management personnel from their normal responsibilities. Such litigation or proceedings could substantially increase our operating losses and reduce the resources available for development activities or any future sales, marketing or distribution activities. We may not have sufficient financial or other resources to adequately conduct such litigation or proceedings. Some of our competitors may be able to sustain the costs of such litigation or proceedings more effectively than we can because of their greater financial resources and more mature and developed intellectual property portfolios. Uncertainties resulting from the initiation and continuation of patent litigation or other proceedings could have a material adverse effect on our ability to compete in the marketplace.

Third parties asserting their patent or other intellectual property rights against us may seek and obtain injunctive or other equitable relief, which could effectively block our ability to further develop and commercialize our drug candidates or force us

to cease some of our business operations. Defense of these claims, regardless of their merit, would involve substantial litigation expense and would be a substantial diversion of management and other employee resources from our business, cause development delays, and may impact our reputation. Claims that we have misappropriated the confidential information or trade secrets of third parties could have a similar negative impact on our business.

In the event we are able to establish third-party infringement of our patents, the court may decide not to grant an injunction against further infringing activity and instead award only monetary damages, which may or may not be an adequate remedy. Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be compromised by disclosure during this type of litigation. In addition, there could be public announcements of the results of hearings, motions or other interim proceedings or developments. If securities analysts or investors perceive these results to be negative, it could have a substantial adverse effect on the price of our ordinary shares..

If we are unable to avoid infringing the patent rights of others, we may be required to seek a license, defend an infringement action, or challenge the validity of the patents in court. Patent litigation is costly and time consuming. We may not have sufficient resources to bring these actions to a successful conclusion. In addition, if we do not obtain a license, develop or obtain non-infringing technology, fail to defend an infringement action successfully, or have infringed patents declared invalid, we may:

•incur substantial monetary damages, including treble damages and attorneys’ fees for willful infringement;

•obtain one or more licenses from third parties and potentially pay royalties;

•redesign our infringing products, which may be impossible on a cost-effective basis or require substantial time and monetary expenditure;

•encounter significant delays in bringing our drug candidates to market; and/or

•be precluded from participating in the manufacture, use, or sale of our drug candidates or methods of treatment requiring licenses.

In that event, we would be unable to further develop and commercialize our drug candidates, which could harm our business significantly.

If our trademarks and trade names are not adequately protected, then we may not be able to build name recognition in our markets of interest and our business may be adversely affected.

Our current or future trademarks or trade names may be challenged, infringed, circumvented, declared generic or descriptive, or determined to be infringing on other marks. We may not be able to protect our rights to these trademarks and trade names or may be forced to stop using these names, which we need for name recognition by potential partners or customers in our markets of interest. During trademark registration proceedings, we may receive rejections of our applications by the USPTO or in other foreign jurisdictions. Although we would be given an opportunity to respond to those rejections, we may be unable to overcome such rejections. In addition, in the USPTO and in comparable agencies in many foreign jurisdictions, third parties are given an opportunity to oppose pending trademark applications and to seek to cancel registered trademarks. Opposition or cancellation proceedings may be filed against our trademarks, and our trademarks may not survive such proceedings. If we are unable to establish name recognition based on our trademarks and trade names, we may not be able to compete effectively and our business may be adversely affected. We may license our trademarks and trade names to third parties, such as distributors. Though these license agreements may provide guidelines for how our trademarks and trade names may be used, a breach of these agreements or misuse of our trademarks and tradenames by our licensees may jeopardize our rights in or diminish the goodwill associated with our trademarks and trade names.

Moreover, any name we have proposed to use with our drug candidate in the United States must be approved by the FDA, regardless of whether we have registered it, or applied to register it, as a trademark. Similar requirements exist in Europe. The FDA typically conducts a review of proposed product names, including an evaluation of potential for confusion with other product names. If the FDA (or an equivalent administrative body in a foreign jurisdiction) objects to any of our proposed proprietary product names, it may be required to expend significant additional resources in an effort to identify a suitable substitute name that would qualify under applicable trademark laws, not infringe the existing rights of third parties and be acceptable to the FDA. Furthermore, in many countries, owning and maintaining a trademark registration may not provide an adequate defense against a subsequent infringement claim asserted by the owner of a senior trademark. At times, competitors or other third parties may adopt trade names or trademarks similar to ours, thereby impeding our ability to build brand identity and possibly leading to market confusion. In addition, there could be potential trade name or trademark infringement claims brought by owners of other registered trademarks or trademarks that incorporate variations of our registered or unregistered trademarks or trade names. If we assert trademark infringement claims, a court may determine that the marks we have asserted are invalid

or unenforceable, or that the party against whom we have asserted trademark infringement has superior rights to the marks in question. In this case, we could ultimately be forced to cease use of such trademarks.

We may be unable to adequately prevent disclosure of trade secrets and other proprietary information.

We rely on trade secrets to protect our proprietary technologies, especially where we do not believe patent protection is appropriate or obtainable; however, trade secrets are difficult to protect. We rely in part on confidentiality agreements with our employees, consultants, outside scientific collaborators, sponsored researchers, and other advisors to protect our trade secrets and other proprietary information. These agreements may not effectively prevent disclosure of confidential information and may not provide an adequate remedy in the event of unauthorized disclosure of confidential information. Any disclosure, either intentional or unintentional, by our employees, the employees of third parties with whom we share our facilities or third-party consultants and vendors that we engage to perform research, clinical trials or manufacturing activities, or misappropriation by third parties (such as through a cybersecurity breach) of our trade secrets or proprietary information could enable competitors to duplicate or surpass our technological achievements, thus eroding our competitive position in our market. In addition, others may independently discover our trade secrets and proprietary information, and we would have no right to prevent them from using that technology or information to compete with us. Costly and time-consuming litigation could be necessary to enforce and determine the scope of our proprietary rights, and failure to obtain or maintain trade secret protection could adversely affect our competitive business position. Furthermore, the laws of some foreign countries do not protect proprietary rights to the same extent or in the same manner as the laws of the United States. As a result, we may encounter significant problems in protecting and defending our intellectual property both in the United States and abroad. If we are unable to prevent unauthorized material disclosure of our intellectual property to third parties, or misappropriation of our intellectual property by third parties, we will not be able to establish or maintain a competitive advantage in our market, which could materially adversely affect our business, operating results, and financial condition.

We may be subject to claims that our employees, collaborators, partners, contractors, or advisors have wrongfully used or disclosed alleged trade secrets of third parties.

Many of our employees were previously employed at universities, Elan or Elan subsidiaries, or other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Likewise, our collaborators, partners, contractors, and advisors may have in the past, or may currently, work with or for universities, or other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Although we try to ensure that our employees do not use the proprietary information or know-how of third parties is not disclosed to us or used in their work for us, we may be subject to claims that we or our employees, collaborators, partners, contractors, or advisors have used or disclosed intellectual property, including trade secrets or other proprietary information, of third parties. Litigation may be necessary to defend against these claims. Even if we are successful in defending against these claims, litigation could result in substantial cost and be a distraction to our management and employees. If our defenses to these claims fail, in addition to requiring us to pay monetary damages, a court could prohibit us from using technologies or features that are essential to our drug candidates, if such technologies or features are found to incorporate, be derived from, or benefited from the knowledge of the trade secrets or other proprietary information of third parties. Moreover, any such litigation or the threat thereof may adversely affect our reputation, our ability to form strategic alliances or sublicense our rights to collaborators, engage with scientific advisors or hire employees or consultants, each of which would have an adverse effect on our business, results of operations and financial condition. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management.

Intellectual property rights do not necessarily address all potential threats to our competitive advantage.

The degree of future protection afforded by our intellectual property rights is uncertain because intellectual property rights have limitations and may not adequately protect our business or permit us to maintain our competitive advantage. For example:

•others may be able to make drug candidates that are similar to ours but that are not covered by the claims of the patents that we own or have exclusively licensed;

•we or our licensors or future collaborators might not have been the first to make the inventions covered by the issued patent or pending patent application that we own or have exclusively licensed;

•we or our licensors or future collaborators might not have been the first to file patent applications covering certain of our inventions;

•others may independently develop similar or alternative technologies or duplicate any of our technologies without infringing our intellectual property rights;

•it is possible that our pending patent applications will not lead to issued patents;

•issued patents that we own or have exclusively licensed may be held invalid or unenforceable, as a result of legal challenges by our competitors;

•our competitors might conduct research and development activities in countries where we do not have patent rights and then use the information learned from such activities to develop competitive products for sale in our major commercial markets;

•we may not develop additional proprietary technologies that are patentable;

•we cannot predict the scope of protection of any patent issuing based on our patent applications, including whether the patent applications that we own or in-license will result in issued patents with claims that cover our drug candidates or uses thereof in the United States or in other foreign countries;

•the claims of any patent issuing based on our patent applications may not provide protection against competitors or any competitive advantages, or may be challenged by third parties;

•if enforced, a court may not hold that our patents are valid, enforceable and infringed;

•we may need to initiate litigation or administrative proceedings to enforce and/or defend our patent rights which will be costly whether we win or lose;

•we may choose not to file a patent in order to maintain certain trade secrets or know-how, and a third party may subsequently file a patent covering such intellectual property;

•we may fail to adequately protect and police our trademarks and trade secrets; and

•the patents of others may have an adverse effect on our business, including if others obtain patents claiming subject matter similar to or improving that covered by our patents and patent applications.

Should any of these events occur, they could significantly harm our business, results of operations, and prospects.

Risks Related to Our Ordinary Shares

The market price of our ordinary shares may fluctuate widely.

Our ordinary shares commenced trading on the Nasdaq Global Market on December 21, 2012 and currently trade on the Nasdaq Global Select Market. We cannot predict the prices at which our ordinary shares may trade. The market price of our ordinary shares may fluctuate widely, depending upon many factors, some of which may be beyond our control, including:

•our ability to obtain financing as needed;

•progress in and results from our ongoing or future nonclinical research and clinical trials;

•our collaborations with third parties, including with Roche and BMS;

•failure or delays in advancing our nonclinical drug candidates or other drug candidates we may develop in the future into clinical trials;

•results of clinical trials conducted by others, including on drugs that would compete with our drug candidates;

•issues in manufacturing our drug candidates;

•regulatory developments or enforcement in the U.S. and other countries;

•developments or disputes concerning patents or other proprietary rights;

•introduction of technological innovations or new commercial products by our competitors;

•changes in estimates or recommendations by securities analysts, if any, who cover our company;

•public concern over our drug candidates;

•litigation;

•future sales of our ordinary shares by us or by existing shareholders;

•general market conditions;

•changes in the structure of healthcare payment systems;

•failure of any of our drug candidates, if approved, to achieve commercial success;

•economic and other external factors or other disasters or crises;

•period-to-period fluctuations in our financial results;

•overall fluctuations in U.S. equity markets;

•our quarterly or annual results, or those of other companies in our industry;

•announcements by us or our competitors of significant acquisitions or dispositions;

•the operating and ordinary share price performance of other comparable companies;

•investor perception of our company and the drug development industry;

•natural or environmental disasters that investors believe may affect us;

•changes in tax laws or regulations applicable to our business or the interpretations of those tax laws and regulations by taxing authorities; or

•fluctuations in the budgets of federal, state and local governmental entities around the world.

These and other external factors may cause the market price and demand for our ordinary shares to fluctuate substantially, which may limit or prevent investors from readily selling their ordinary shares and may otherwise negatively affect the liquidity of our ordinary shares. In particular, stock markets in general have experienced volatility that has often been unrelated to the operating performance of a particular company. These broad market fluctuations may adversely affect the trading price of our ordinary shares. Some companies that experienced volatility in the trading price of their stock have been the subject of securities class action litigation. If any of our shareholders brought a lawsuit against us, we could incur substantial costs defending the lawsuit. Such a lawsuit could also divert the time and attention of our management.

Your percentage ownership in Prothena may be diluted in the future.

As with any publicly traded company, your percentage ownership in us may be diluted in the future because of equity issuances for acquisitions, capital raising transactions (including the sale of ordinary shares under our ATM), or otherwise. We may need to raise additional capital in the future. If we are able to raise additional capital, we may issue equity or convertible debt instruments, which may severely dilute your ownership interest in us. In addition, we intend to continue to grant option awards to our directors, officers and employees, which would dilute your ownership stake in us. As of September 30, 2021, the number of ordinary shares available for issuance pursuant to outstanding and future equity awards under our equity plan was 11,802,724.

If we are unable to maintain effective internal controls, our business could be adversely affected.

We are subject to the reporting and other obligations under the U.S. Securities Exchange Act of 1934, as amended, including the requirements of Section 404 of the U.S. Sarbanes-Oxley Act, which require annual management assessments of the effectiveness of our internal control over financial reporting. In addition, under Section 404(b) of the U.S. Sarbanes-Oxley Act, if we are either an “accelerated filer” or “large accelerated filer,” our independent registered public accounting firm must attest to the effectiveness of our internal control over financial reporting. The rules governing the standards that must be met for management to assess our internal control over financial reporting are complex and require significant documentation, testing and possible remediation to meet the detailed standards under the rules. During the course of its testing, our management may identify material weaknesses or deficiencies which may not be remedied in time to meet the deadline imposed by the Sarbanes-Oxley Act. These reporting and other obligations place significant demands on our management and administrative and operational resources, including accounting resources.

Our management is responsible for establishing and maintaining adequate internal control over financial reporting. Our internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of our financial statements for external purposes in accordance with accounting principles generally accepted in the U.S. During the course of our review and testing of our internal controls, we may identify deficiencies and be unable to remediate them before we must provide the required reports. Furthermore, if we have a material weakness in our internal controls over financial reporting, we may not detect errors on a timely basis and our consolidated financial statements may be materially misstated. We, or our independent registered public accounting firm (if required), may not be able to conclude on an ongoing basis that we have effective internal control over financial reporting, which could harm our operating results, cause investors to lose confidence in our reported financial information and cause the trading price of our stock to fall.

We cannot provide assurance that a material weakness will not occur in the future, or that we will be able to conclude on an ongoing basis that we have effective internal controls over financial reporting in accordance with Section 404 and the related rules and regulations of the SEC when required. A material weakness in internal control over financial reporting is a deficiency, or a combination of deficiencies, in internal control over financial reporting, such that there is a reasonable possibility that a

material misstatement of a company’s annual or interim consolidated financial statements will not be prevented or detected on a timely basis by the company’s internal controls. If we cannot in the future favorably assess, or our independent registered public accounting firm (if required), is unable to provide an unqualified attestation report on, the effectiveness of our internal controls over financial reporting, investor confidence in the reliability of our financial reports may be adversely affected, which could have a material adverse effect on our share price. In addition, any failure to report our financial results on an accurate and timely basis could result in sanctions, lawsuits, delisting of our shares from the Nasdaq Global Select Market or other adverse consequences that would have an adverse effect on our business, financial position and results of operations.

If we were treated as a passive foreign investment company for U.S. federal income tax purposes, it could result in adverse U.S. federal income tax consequences to United States holders of our ordinary shares.

Significant potential adverse U.S. federal income tax implications generally apply to U.S. investors owning shares of a passive foreign investment company (“PFIC”), directly or indirectly. In general, we would be a PFIC for a taxable year if either (i) 75% or more of our income constitutes passive income, or (ii) 50% or more of our assets produce passive income are held for the production of passive income. Changes in the composition of our active or passive income, passive assets or changes in our fair market value may cause us to become a PFIC. A separate determination must be made each taxable year as to whether we are a PFIC (after the close of each taxable year).

We do not believe we were a PFIC for U.S. federal income tax purposes for our taxable year ended December 31, 2020. However, the application of the PFIC rules is subject to uncertainties in a number of respects, and we cannot assure that the U.S. Internal Revenue Service (the “IRS”) will not take a contrary position. We also cannot assure that we will not be a PFIC for U.S. federal income tax purposes for the current taxable year or any future taxable year.

We may not be able to successfully maintain our tax rates, which could adversely affect our business and financial condition, results of operations and growth prospects.

We are incorporated in Ireland and maintain subsidiaries or offices in Ireland and the U.S. We are able to achieve a low average tax rate through the performance of certain functions and ownership of certain assets in tax-efficient jurisdictions, together with intra-group service agreements. However, changes in tax laws or interpretations thereof in any of these jurisdictions could adversely affect our ability to do so in the future. Taxing authorities, such as the IRS and the Irish Revenue Commissioners (“Irish Revenue”), actively audit and otherwise challenge these types of arrangements, and have done so in our industry. We are subject to reviews and audits by the IRS, Irish Revenue and other taxing authorities from time to time, and the IRS, Irish Revenue or other taxing authority may challenge our structure and inter-group arrangements. Responding to or defending against challenges from taxing authorities could be expensive and time consuming, and could divert management’s time and focus away from operating our business. We cannot predict whether and when taxing authorities will conduct an audit, challenge our tax structure or the cost involved in responding to any such audit or challenge. If we are unsuccessful, we may be required to pay taxes for prior periods, interest, fines or penalties, and may be obligated to pay increased taxes in the future, all of which could have an adverse effect on our business, financial condition, results of operations, and/or growth prospects.

Future changes to the tax laws relating to multinational corporations could adversely affect us.

Under current law, we are treated as a foreign corporation for U.S. federal tax purposes. However, changes to the U.S. Internal Revenue Code, U.S. Treasury Regulations or other IRS guidance thereunder could adversely affect our status as a foreign corporation or otherwise affect our effective tax rate. For example, in 2017 the United States enacted tax reform that contained significant changes to corporate taxation, including a provision that would require capitalization and amortization of research and development costs over five years for tax years beginning after December 31, 2021. In addition, the Irish Government, Irish Revenue, U.S. Congress, the IRS, the Organization for Economic Co-operation and Development, and other governments and agencies in jurisdictions where we do business have recently focused on issues related to the taxation of multinational corporations, and specifically in the area of “base erosion and profit shifting,” such as where payments are made between affiliates from a jurisdiction with high tax rates to a jurisdiction with lower tax rates. As a result, the tax laws in Ireland, the U.S., and other countries in which we do business could change on a prospective or retroactive basis, and any such changes could have an adverse effect on our business, financial condition, results of operations, and/or growth prospects.

Irish law differs from the laws in effect in the United States and may afford less protection to holders of our ordinary shares.

It may not be possible to enforce court judgments obtained in the U.S. against us in Ireland based on the civil liability provisions of the U.S. federal or state securities laws. In addition, there is uncertainty as to whether the courts of Ireland would recognize or enforce judgments of U.S. courts obtained against us or our directors or officers based on the civil liabilities provisions of the U.S. federal or state securities laws or hear actions against us or those persons based on those laws. We have been advised that the U.S. currently does not have a treaty with Ireland providing for the reciprocal recognition and enforcement of judgments in civil and commercial matters. Therefore, a final judgment for the payment of money rendered by

any U.S. federal or state court based on civil liability, whether or not based solely on federal or state securities laws, would not automatically be enforceable in Ireland.

As an Irish incorporated company, we are governed by the Irish Companies Act 2014, as amended (the “Companies Act”), which differs in some material respects from laws generally applicable to U.S. corporations and shareholders, including, among others, differences relating to interested director and officer transactions and shareholder lawsuits. Likewise, the duties of directors and officers of an Irish company generally are owed to the company only. Shareholders of Irish companies generally do not have a personal right of action against directors or officers of the company and may exercise such rights of action on behalf of the company only in limited circumstances. Accordingly, holders of our ordinary shares may have more difficulty protecting their interests than would holders of securities of a corporation incorporated in a jurisdiction of the U.S.

The operation of the Irish Takeover Rules may affect the ability of certain parties to acquire our ordinary shares.

Under the Irish Takeover Rules, if an acquisition of ordinary shares were to increase the aggregate holding of the acquirer and its concert parties to ordinary shares that represent 30% or more of the voting rights of the company, the acquirer and, in certain circumstances, its concert parties would be required (except with the consent of the Irish Takeover Panel) to make an offer for the outstanding ordinary shares at a price not less than the highest price paid for the ordinary shares by the acquirer or its concert parties during the previous 12 months. This requirement would also be triggered by an acquisition of ordinary shares by a person holding (together with its concert parties) ordinary shares that represent between 30% and 50% of the voting rights in the company if the effect of such acquisition were to increase that person’s percentage of the voting rights by 0.05% within a 12 month period. Under the Irish Takeover Rules, certain separate concert parties are presumed to be acting in concert. Our board of directors and their relevant family members, related trusts and “controlled companies” are presumed to be acting in concert with any corporate shareholder who holds 20% or more of our shares. The application of these presumptions may result in restrictions upon the ability of any of the concert parties and/or members of our board of directors to acquire more of our securities, including under the terms of any executive incentive arrangements. In the future, we may consult with the Irish Takeover Panel with respect to the application of this presumption and the restrictions on the ability to acquire further securities, although we are unable to provide any assurance as to whether the Irish Takeover Panel will overrule this presumption. Accordingly, the application of the Irish Takeover Rules may restrict the ability of certain of our shareholders and directors to acquire our ordinary shares.

Irish law differs from the laws in effect in the United States with respect to defending unwanted takeover proposals and may give our board of directors less ability to control negotiations with hostile offerors.

We are subject to the Irish Takeover Panel Act, 1997, Takeover Rules, 2013. Under those Irish Takeover Rules, our Board is not permitted to take any action that might frustrate an offer for our ordinary shares once our Board has received an approach that may lead to an offer or has reason to believe that such an offer is or may be imminent, subject to certain exceptions. Potentially frustrating actions such as (i) the issue of ordinary shares, options or convertible securities, (ii) material acquisitions or disposals, (iii) entering into contracts other than in the ordinary course of business, or (iv) any action, other than seeking alternative offers, which may result in frustration of an offer, are prohibited during the course of an offer or at any earlier time during which our Board has reason to believe an offer is or may be imminent. These provisions may give our Board less ability to control negotiations with hostile offerors and protect the interests of holders of ordinary shares than would be the case for a corporation incorporated in a jurisdiction of the U.S.

Irish law requires that our shareholders renew every five years the authority of our Board of Directors to issue shares and to do so for cash without applying the statutory pre-emption right, and if our shareholders do not renew these authorizations by May 17, 2022 (or any renewal is subject to limitations), our ability to raise additional capital to fund our operations would be limited.

As an Irish incorporated company, we are governed by the Companies Act. The Companies Act requires that every five years our shareholders renew the separate authorities of our Board to (a) allot and issue shares, and (b) opt out of the statutory pre-emption right that otherwise applies to share issuances for cash (which pre-emption right would require that shares issued for cash be offered to our existing shareholders on a pro rata basis before the shares may be issued to new shareholders). At our shareholders' annual general meeting held on May 17, 2017, our shareholders authorized our Board to issue ordinary shares up to the amount of our authorized share capital, and to opt out of the statutory pre-emption right for such issuances. Under Irish law, these authorizations will expire on May 17, 2022, five years after our shareholders last renewed these authorizations. Irish law requires that our shareholders renew the authority for our Board to issue ordinary shares by a resolution approved by not less than 50% of the votes cast at a general meeting of our shareholders. Irish law requires that our shareholders renew the authority of our Board to opt out of the statutory pre-emption right in share issuances for cash by a resolution approved by not less than 75% of the votes cast at a general meeting of our shareholders. If these authorizations are not renewed before May 17, 2022, or are renewed with limitations, our Board would be limited in its ability to issue shares, which would limit our ability to

raise additional capital to fund our operations, including the research, development and potential commercialization of our drug candidates.

Transfers of our ordinary shares may be subject to Irish stamp duty.

Irish stamp duty may be payable in respect of transfers of our ordinary shares (currently at the rate of 1% of the price paid or the market value of the shares acquired, if greater).

Under the Irish Stamp Duties Consolidation Act, 1999 (the “Stamp Duties Act”), a transfer of our ordinary shares from a seller who holds shares through The Depository Trust Company (“DTC”) to a buyer who holds the acquired shares through DTC should not be subject to Irish stamp duty. Shareholders may also transfer their shares into or out of DTC without giving rise to Irish stamp duty provided that there is no change in the beneficial ownership of such shares and the transfer into or out of DTC is not effected in contemplation of a subsequent sale of such shares to a third party; in order to benefit from this exemption from Irish stamp duty, the seller must confirm to us that there is no change in the ultimate beneficial ownership of the shares as a result of the transfer and there is no agreement for the sale of the shares by the beneficial owner to a third party being contemplated.

A transfer of our ordinary shares (i) by a seller who holds shares outside of DTC to any buyer, or (ii) by a seller who holds the shares through DTC to a buyer who holds the acquired shares outside of DTC, may be subject to Irish stamp duty. Payment of any Irish stamp duty is generally a legal obligation of the transferee.

Any Irish stamp duty payable on transfers of our ordinary shares could adversely affect the price of those shares.

We do not anticipate paying cash dividends, and accordingly, shareholders must rely on ordinary share appreciation for any return on their investment.

We anticipate losing money for the foreseeable future and, even if we do turn a profit, we do not anticipate declaring or paying any cash dividends for the foreseeable future. Therefore, the success of an investment in our ordinary shares will depend upon appreciation in their value and in order to receive any income or realize a return on your investment, you will need to sell your Prothena ordinary shares. There can be no assurance that our ordinary shares will maintain their price or appreciate in value.

Dividends paid by us may be subject to Irish dividend withholding tax.

Although we do not currently anticipate paying cash dividends, if we were to do so in the future, a dividend withholding tax (currently at a rate of 25%) may arise. A number of exemptions from dividend withholding tax exist such that shareholders resident in the U.S. and shareholders resident in other countries that have entered into a double taxation treaty with Ireland may be entitled to exemptions from dividend withholding tax subject to the completion of certain dividend withholding tax declaration forms.

Shareholders entitled to an exemption from Irish dividend withholding tax on any dividends received from us will not be subject to Irish income tax in respect of those dividends, unless they have some connection with Ireland other than their shareholding (for example, they are resident in Ireland). Non-Irish resident shareholders who receive dividends subject to Irish dividend withholding tax will generally have no further liability to Irish income tax on those dividends.

Prothena ordinary shares received by means of a gift or inheritance could be subject to Irish capital acquisitions tax.

Irish capital acquisitions tax (“CAT”) could apply to a gift or inheritance of our ordinary shares irrespective of the place of residence, ordinary residence or domicile of the parties. This is because our ordinary shares will be regarded as property situated in Ireland. The person who receives the gift or inheritance has primary liability for CAT. Gifts and inheritances passing between spouses are exempt from CAT. It is recommended that each shareholder consult his or her own tax advisor as to the tax consequences of holding our ordinary shares or receiving dividends from us.

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS

None.

ITEM 3. DEFAULTS UPON SENIOR SECURITIES

None.

ITEM 4. MINE SAFETY DISCLOSURES

Not Applicable.

ITEM 5. OTHER INFORMATION

None.

ITEM 6. EXHIBITS

EXHIBIT INDEX

Previously Filed

Exhibit
No.

Description

Form

File No.

Filing Date

Exhibit

Filed Herewith

10.1#

Tenth Amendment to the Prothena Corporation plc 2020 Employment Inducement Incentive Plan

10.2#

Amended and Restated Consulting Agreement, dated July 15, 2020, between Prothena Biosciences Inc and Dennis J. Selkoe

10.3+

Amendment No. 2 to License, Development, and Commercialization Agreement, entered into on December 11, 2013, among Prothena Biosciences Limited, Prothena Biosciences Inc, F. Hoffman-La Roche Ltd and Hoffman-La Roche Inc.

10.4+

Share Purchase Agreement, dated as of July 8, 2021, by and among Novo Nordisk A/S, Novo Nordisk Region Europe A/S, Prothena Corporation plc, and Prothena Biosciences Limited

10.5+

U.S. License Agreement, dated as of July 30, 2021, as amended on August 12, 2021 and September 8, 2021, by and between Prothena Biosciences Limited and Celgene Switzerland LLC

31.1

Certification of Principal Executive Officer pursuant to Rule 13a-14(a) and 15d-14(a) of the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002

31.2

Certification of Principal Financial Officer pursuant to Rule 13a-14(a) and 15d-14(a) of the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002

32.1*

Certification of Principal Executive Officer and Principal Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

101.INS

XBRL Instance Document - The instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document

101.SCH

Inline XBRL Taxonomy Extension Schema Document

101.CAL

Inline XBRL Taxonomy Extension Calculation Linkbase Document

101.DEF

Inline XBRL Taxonomy Extension Definition Linkbase Document

101.LAB

Inline XBRL Taxonomy Extension Label Linkbase Document

Previously Filed

Exhibit
No.

Description

Form

File No.

Filing Date

Exhibit

Filed Herewith

101.PRE

Inline XBRL Taxonomy Extension Presentation Linkbase Document

104

Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101)

_______________

# Indicates management contract or compensatory plan or arrangement.

+ Certain information in this exhibit (indicated by asterisks) has been excluded pursuant to Regulation S-K, Item 601(b)(10). Such information is both not material and the type of information that the registrant customarily and actually treats as private and confidential.

* Exhibit 32.1 is being furnished and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liability of that section, nor shall such exhibit be deemed to be incorporated by reference in any registration statement or other document filed under the Securities Act of 1933, as amended, or the Exchange Act, except as otherwise specifically stated in such filing.

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this Quarterly Report on Form 10-Q to be signed on its behalf by the undersigned, thereunto duly authorized.

Dated:

November 4, 2021

Prothena Corporation plc

(Registrant)

/s/ Gene G. Kinney

Gene G. Kinney

President and Chief Executive Officer

/s/ Tran B. Nguyen

Tran B. Nguyen

Chief Financial Officer and Chief Strategy Officer

Exhibit 10.1

TENTH AMENDMENT TO THE

PROTHENA CORPORATION PLC

2020 EMPLOYMENT INDUCEMENT INCENTIVE PLAN

This Tenth Amendment (this “Tenth Amendment”) to the Prothena Corporation plc 2020 Employment Inducement Incentive Plan (“2020 EIIP”), was made and adopted by the Board of Directors (“Board”) of Prothena Corporation plc, a public limited company organized under the laws of Ireland (the “Company”), on September 1, 2021 (the “Amendment Date”).

RECITALS

WHEREAS, the Company maintains the 2020 EIIP; and

WHEREAS, the Board believes it is in the best interests of the Company and its shareholders to amend the 2020 EIIP to increase the number of ordinary shares authorized for issuance under the 2020 EIIP.

NOW, THEREFORE, BE IT RESOLVED, that the 2020 EIIP is hereby amended as follows, effective as of the Amendment Date:

AMENDMENT

1.Section 2.28 of the 2020 EIIP is hereby amended and restated in its entirety as follows:

“2.28 “Overall Share Limit” means 1,245,000 Shares.”

2.This Tenth Amendment shall be and hereby is incorporated into and forms a part of the 2020 EIIP, and except as expressly provided herein, all terms and conditions of the 2020 EIIP shall remain in full force and effect.

Exhibit 10.2

AMENDED AND RESTATED

CONSULTING AGREEMENT

This Amended and Restated Consulting Agreement (this “Agreement”) is effective as of July 15, 2020 (the “Effective Date”) and is made by and between Dennis J. Selkoe, M.D., an individual (“Consultant”), and Prothena Biosciences Inc, a Delaware corporation with offices at 331 Oyster Point Boulevard, South San Francisco, CA 94080, U.S.A. (“Prothena”). Consultant and Prothena may each be referred to individually herein as a “Party” and collectively as the “Parties”.

WHEREAS, Prothena is engaged in the business of researching and developing therapies for neurodegenerative diseases;

WHEREAS, Consultant is an expert in neurodegenerative diseases;

WHEREAS, Prothena and Consultant previously entered into that certain Consulting Agreement dated July 15, 2020 (the “Prior Agreement”) pursuant to which Consultant to provided services to Prothena; and

WHEREAS, Prothena and Consultant wish to amend and restate the Prior Agreement in its entirety on the terms and conditions set forth in this Agreement.

NOW, THEREFORE, in connection therewith and for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, Consultant and Prothena agree as follows:

1.SCOPE OF SERVICES

1.1Services. Subject to the terms and conditions of this Agreement, Consultant shall perform services to Prothena as requested in connection with its assessment of potential business development opportunities and matters related to partnered collaboration programs (the “Services”).

1.2Performance. Consultant shall perform the Services (a) in a professional, diligent, workmanlike and timely manner, that meets or exceeds the standards and practices that are generally accepted in the industry and exercised by others performing similar services, and (b) in strict compliance with all applicable laws, rules, regulations and guidelines, including but not limited to the U.S. Federal Food, Drug and Cosmetic Act, the U.S. Federal Anti-Kickback Statute, the U.S. Foreign Corrupt Practices Act, and the PhRMA Code on Interactions with Healthcare Professionals. None of the Services nor the Work Product (defined in Section 1.3 below) shall infringe, misappropriate or violate any proprietary rights of any third party.

1.3Work Product. Consultant shall (a) create in a timely and accurate manner, and (b) maintain during the Term (defined in Section 7.1 below), written records of the results, data and other materials and deliverables generated or recorded in the performance of the Services (the “Work Product”), which Work Product shall be owned by, and shall be Confidential Information (defined below) of, Prothena. Promptly upon completion of the Services or

termination of this Agreement, or upon earlier request by Prothena, Consultant shall deliver the Work Product to Prothena.

1.4Independent Contractor. Consultant is an independent contractor and nothing in this Agreement or the Services provided hereunder is intended to reflect or create, or shall be construed as reflecting or creating, the relationship of partners, principal and agent, or employer and employee. Neither Party shall have any express or implied authority to assume or create any obligation on behalf of, or in the name of, the other Party to any contract or undertaking with any third party directly or indirectly as a result of this Agreement. Any taxes, insurance or benefits imposed on Consultant due to his business activities, including any Services provided hereunder, shall be the sole responsibility of Consultant.

1.5Prothena Affiliates. Prothena may specify that the Consultant’s Services will be for the benefit of an Affiliate of Prothena. The term “Affiliate” means any entity that controls, is controlled by or is under common control with Prothena.

2.COMPENSATION, EXPENSES AND INVOICING

2.1Compensation. Prothena shall pay Consultant at the rate of $500.00 for each hour of Services actually performed by Consultant. For the avoidance of doubt, travel time, if any, required to perform the Services shall not be billable except to the extent that Services are actually performed during such time.

2.2Travel and Other Expenses. Prothena shall reimburse Consultant for reasonable travel and other expenses actually incurred by Consultant, without commission or mark-up, to the extent necessary to perform the Services.

2.3Maximum Amount Payable. Notwithstanding anything to the contrary herein, the maximum aggregate amount payable to Consultant under this Agreement, including for reimbursement of expenses, shall not exceed $60,000.

2.4Invoicing. Consultant shall submit to Prothena a written invoice (“Invoice”) monthly for Services actually performed and expenses actually incurred. Each such Invoice shall include (a) a description of the Services performed, by date, and the amount of time spent for each Service, (b) the compensation earned by Consultant in accordance with Section 2.1 above, and (c) the reimbursable expenses incurred by Consultant in accordance with Section 2.2 above. Invoices shall be sent by e-mail to Accounting@Prothena.com. Prothena shall pay to Consultant all undisputed amounts due no later than thirty (30) days from Prothena’s receipt of the applicable Invoice; provided, however, that Prothena may withhold payment pending delivery by Consultant to Prothena of any Work Product.

3.CONFIDENTIALITY

3.1Confidential Information. “Confidential Information” means any and all confidential, proprietary and/or trade secret information or materials that are directly or indirectly disclosed by or on behalf of Prothena or its Affiliates to Consultant or its Affiliates in connection with this Agreement. Confidential Information includes, without limitation, trade secrets,

processes, formulae, data, know-how, improvements, inventions, techniques, marketing plans, strategies, forecasts, employees and customer and contact lists.

3.2Exceptions. Confidential Information shall not include any information that Consultant can demonstrate by competent written evidence (a) previously was in his possession, as shown by its pre-existing records, without violation of any obligation of confidentiality, (b) has become publicly known through no wrongful act of or breach of this Agreement by Consultant, (c) was received by Consultant without breach of this Agreement from a third party without restriction as to the use and disclosure of the information, or (d) was independently developed by Consultant without use of the Confidential Information.

3.3Confidentiality. Consultant shall maintain in confidence and shall not disclose or use for any purpose other than as expressly provided for in this Agreement any Confidential Information. Consultant may use and disclose Confidential Information only to its directors, officers, employees and permitted subcontractors, and solely to the extent required and for the purpose of performing the Services. Consultant shall not use the Confidential Information for any purpose or in any manner that would constitute a violation of any law, rule, regulation or guideline. Consultant shall ensure that any of its directors, officers, employees and subcontractors receiving any Confidential Information as permitted under this Agreement shall be informed of the confidential nature of such Confidential Information and shall be bound by confidentiality obligations at least as strict as the confidentiality obligations in this Agreement to protect the confidentiality of such Confidential Information. Any failure by any such directors, officers, employee or subcontractors of Consultant to meet the foregoing obligations shall be deemed to be a breach by Consultant.

3.4Authorized Disclosures. If Consultant is required by a valid order of a court or other governmental body or otherwise required by the law to disclose Confidential Information, it shall give Prothena timely written notice of such a requirement before doing so and shall cooperate with Prothena to seek a protective order, confidential treatment or other appropriate protections of such Confidential Information.

3.5Notice. Consultant will promptly report to Prothena any actual or suspected breach of the terms of this Section 3, and will take all reasonable further steps requested by Prothena to prevent, control or remedy any such breach.

3.6Return of Confidential Information. Upon request of Prothena or the termination of this Agreement, Consultant shall (a) return to Prothena all tangible forms of the Confidential Information and (b) destroy all electronic forms of the Confidential Information, including all notes, reports or other documents prepared by Consultant that contain any Confidential Information in Consultant’s possession, custody or control, within thirty (30) days of such request or termination; provided, however, that Consultant may retain a single copy of the Confidential Information in a secure format for the sole purpose of determining the scope of Consultant’s obligations under this Agreement.

3.7Survival. The confidentiality and non-use obligations set forth in this Section 3 shall survive termination of this Agreement and continue for a period of seven (7) years following the date of such termination of this Agreement.

3.8Injunctive Relief and Irreparable Harm. Consultant agrees that its breach of any of the obligations of this Section 3 may cause Prothena irreparable damage for which recovery of money damages may be inadequate. Prothena will, therefore, be entitled to seek timely injunctive relief without the necessity of proving money damages, in addition to any and all remedies available at law or equity.

3.9Defend Trade Secrets Act Notice of Immunity Rights. Consultant acknowledges that the Company has provided Consultant with the following notice of immunity rights in compliance with the requirements of the Defend Trade Secrets Act: (a) Consultant will not be held criminally or civilly liable under any Federal or State trade secret law for the disclosure of Confidential Information that is made in confidence to a Federal, State or local government official or to an attorney solely for the purpose of reporting or investigating a suspected violation of law; (b) Consultant will not be held criminally or civilly liable under any Federal or State trade secret law for the disclosure of Confidential Information that is made in a complaint or other document filed in a lawsuit or other proceeding, if such filing is made under seal; and (c) if Consultant files a lawsuit for retaliation by the Company for reporting a suspected violation of law, Consultant may disclose the Confidential Information to its attorney and use the Confidential Information in the court proceeding, if Consultant files any document containing the Confidential Information under seal, and does not disclose the Confidential Information, except pursuant to court order.

4.INTELLECTUAL PROPERTY

4.1Intellectual Property. “Intellectual Property” means any and all ideas, concepts, discoveries, inventions, developments, formulae, processes, know-how, trade secrets, techniques, materials, methodologies, modifications, inventions, innovations, improvements, processes, writings, documentation, electronic code, data and rights (whether or not protectable under state, federal or other jurisdictions’ patent, trademark, copyright or similar laws) or the like, whether or not written or otherwise fixed in any form or medium, regardless of the media on which contained and whether or not patentable or copyrightable, and all intellectual property rights therein.

4.2Project IP. Prothena shall solely and exclusively own all right, title and interest in and to the Work Product and all Intellectual Property arising during the course of performance of the Services, whether made solely by either Party or jointly by the Parties (collectively, the “Project IP”). Consultant hereby assigns to Prothena, its successors or assigns, as the case may be, all rights, titles and interest in the Project IP. Consultant shall promptly notify Prothena in writing of any inventions within the Project IP conceived of, or reduced to practice, by Consultant, together with a reasonable description of any such invention.

4.3Assistance. Consultant agrees to execute such documents and take such action as Prothena may request to memorialize, secure and perfect Prothena’s interest in the Project IP. If Prothena is unable for any reason, after reasonable effort, to secure Consultant’s signature on any document needed in connection with the actions specified above, Consultant hereby irrevocably designates and appoints Prothena as Consultant’s duly authorized officers and agents as Consultant’s agent and attorney-in-fact, which appointment is coupled with an interest, to act for

and on Consultant’s behalf to execute, verify and file any such documents and to do all other lawfully permitted acts to further the purposes of the preceding paragraph with the same legal force and effect as if executed by Consultant.

4.4No Other Rights. Delivery of any Intellectual Property or Confidential Information of Prothena to Consultant shall not be deemed to grant to Consultant any right or licenses under such Confidential Information or under any Intellectual Property of Prothena, including without limitation the Work Product or any Project IP, except as expressly set forth in this Agreement.

5.REPRESENTATIONS AND WARRANTIES

5.1By Each Party. Each Party represents and warrants to the other Party that (a) it has the full power and authority to enter into this Agreement, (b) this Agreement has been duly authorized, and (c) this Agreement is binding upon it.

5.2By Consultant. Consultant represents and warrants that (a) entering into this Agreement and performing the Services and obligations contemplated under this Agreement would not violate any law, rule, regulation or judicial order applicable to Consultant, and would not violate or constitute a default under any agreement to which Consultant is a party, and (b) Consultant is not (i) under investigation by the U.S. Food and Drug Administration or any other governmental agency or authority that could result in any debarment, sanction or exclusion action (a “Debarment”), (ii) subject to a Debarment, or (iii) currently excluded or otherwise ineligible from participating in any governmental health care program. In the event that Consultant becomes the subject of an investigation that could result in a Debarment or becomes subject to a Debarment, Consultant shall immediately notify Prothena in writing. Upon the receipt of such notice by Prothena, or if Prothena otherwise becomes aware of such Debarment or threatened Debarment, Prothena shall have the right to terminate this Agreement immediately.

6.INDEMNIFICATION

6.1By Consultant. Consultant shall indemnify and hold Prothena and its Affiliates, and their respective directors, officers, employees and agents (each a “Prothena Indemnitee”), harmless from and against any and all liabilities, losses, damages or expenses of any kind, including costs and reasonable attorneys’ fees (collectively, “Losses”) arising out of or resulting from any third party suit, proceeding, action, claim or demand (collectively, “Claims”) to the extent resulting from (a) any grossly negligent or willful act or omission by Consultant; or (b) any breach of this Agreement by Consultant. Notwithstanding the foregoing, Consultant shall not be obligated to indemnify any Prothena Indemnitee to the extent that the applicable Claim is subject to Prothena’s indemnification obligations under Section 6.2 below.

6.2By Prothena. Prothena shall indemnify and hold Consultant harmless from any and all Losses arising out of or resulting from Claims to the extent resulting from (a) any grossly negligent or willful acts or omissions by Prothena or any of its directors, officers, employees or agents, or (b) any breach of this Agreement by Prothena. Notwithstanding the foregoing, Prothena shall not be obligated to indemnify Consultant to the extent that the applicable Claim is subject to Consultant’s indemnification obligations under Section 6.1 above.

7.TERM AND TERMINATION

7.1Term. The term of this Agreement (the “Term”) shall commence as of the Effective Date and shall terminate on September 30, 2022, unless terminated earlier pursuant to Section 7.2 below.

7.2Termination. Either Party may terminate this Agreement by providing at least ten (10) business days prior written notice to the other Party.

7.3Effect of Termination. Upon any termination of this Agreement:

(a)Consultant shall immediately cease all Services;

(b)Prothena shall pay to Consultant all amounts due for Services performed under this Agreement;

(c)Consultant shall return or destroy, at Prothena’s election, Prothena’s Confidential Information; and

(d)Consultant shall promptly deliver to Prothena the Work Product, or at Prothena’s instruction, destroy the Work Product.

7.4 Survival. Sections 1.3, 3, 4, 6, 7.3 and 8 shall survive any termination of this Agreement.

8.MISCELLANEOUS

8.1Entire Agreement; Amendments. This Agreement contains the entire understanding of the Parties with respect to the subject matter herein and supersedes all previous agreements (oral and written), negotiations and discussions. The Parties may modify or amend the provisions hereof only in a writing duly executed by authorized representatives of the Parties.

8.2Remedies. If (a) Consultant’s Services fail to meet standards set forth in this Agreement, (b) Consultant fails to provide appropriate and timely Services, or (c) Consultant commits any other material error in performance of the Services, Prothena shall in its sole discretion have the right, in addition to any other remedy it may have at law or equity, to (i) require that the applicable Services be remedied or re-performed without charge to Prothena, or (ii) set off the costs of the loss, damage or defect against monies owed to Consultant and/or require Consultant to provide a refund of all amounts paid for such Services.

8.3Notices. All legal notices from one Party to the other will be in writing and will be given by addressing the same to the applicable address set forth below, or at such other address as either may specify in writing to the other. Notices shall be sent by overnight courier, certified mail with return receipt requested, or by other means of delivery requiring an acknowledged receipt. For purposes of clarity, notice may be provided via electronic mail with read receipt requested. All notices shall be effective upon receipt.

To Prothena: Prothena Biosciences Inc

331 Oyster Point Boulevard

South San Francisco, CA 94080, U.S.A.

Attention: Chief Legal Officer and Secretary

To Consultant: Dennis J. Selkoe, M.D.

8.4Assignment. This Agreement and the Services contemplated hereunder are personal to Consultant and Consultant shall not assign, transfer or subcontract any of Consultant’s obligations under this Agreement without the prior written consent of Prothena. Any attempted assignment, transfer or subcontracting in violation hereof shall be null and void. The Company may freely assign this Agreement, and Consultant expressly agrees that any intellectual property rights licensed to the Company are transferable to the Company’s assignee without Consultant’s consent.

8.5Waiver. No waiver by either Party of any obligation under this Agreement, or non-performance thereof, of the other Party shall constitute a waiver of any other obligation or non-performance of such other Party.

8.6Severability. If any provision of this Agreement is declared void or unenforceable, such provision shall be deemed modified to the extent necessary to allow enforcement, and all other portions of this Agreement shall remain in full force and effect.

8.7Governing Law. This Agreement shall be governed by and construed in accordance with the laws of the State of California, without giving effect to any conflicts of laws principles thereof.

8.8Arbitration. To ensure rapid and economical resolution of any disputes unrelated to patent rights regarding this Agreement, in the event any dispute is not resolved by action taken under Section 8.2 above, the Parties hereby agree that any and all claims, disputes or controversies of any nature whatsoever arising out of, or relating to, this Agreement, or its interpretation, enforcement, breach, performance or execution, or services thereunder, shall be resolved, to the fullest extent permitted by law, by final, binding and confidential arbitration in San Francisco, CA under the then applicable American Arbitration Association arbitration rules. The Parties each acknowledge that by agreeing to this arbitration procedure, they waive the right to resolve any such dispute, claim or demand through a trial by jury or judge or by administrative proceeding. The Parties will share the costs of arbitration equally. Both Parties will be responsible for their own attorney’s fees, and the arbitrator may not award attorney’s fees unless a statute or contract at issue specifically authorizes such an award. Nothing in this Agreement is intended to prevent either Party from obtaining injunctive relief in court to prevent irreparable harm pending the conclusion of any arbitration. With respect to injunctive relief, the Parties agree to personal jurisdiction and venue in the state or federal courts of San Francisco, California. With respect to any dispute relating to patent rights, including without limitation the validity, enforceability or scope of any patent, the laws of the applicable country of the patent

shall govern and the courts of such applicable country shall have jurisdiction with regard to any patent dispute.

8.9Execution. This Agreement may be executed in one or more counterparts, each of which shall be deemed an original but all of which together shall constitute one and the same document. This Agreement may be executed electronically (including PDF). The Parties agree that electronic copies of signatures have the same effect as original signatures.

8.10Termination of the Prior Agreement. The Prior Agreement is hereby terminated and superseded in its entirety by this Agreement.

(Signature Page Follows)

IN WITNESS WHEREOF, this Agreement has been executed by the Parties hereto effective as of the Effective Date.

PROTHENA BIOSCIENCES INC DENNIS J. SELKOE, M.D.

By: /s/ Gene Kinney /s/ Dennis Selkoe

Name: Gene G. Kinney, Ph.D. Date: September 30, 2021

Title: President and Chief Executive Officer

Date: September 30, 2021

[Signature Page to Amended and Restated Consulting Agreement]

Exhibit 10.3

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10). Such excluded information is both not material and the type of information that the registrant customarily and actually treats as private and confidential.

AMENDMENT NO. 2 TO LICENSE, DEVELOPMENT, AND COMMERCIALIZATION AGREEMENT

This AMENDMENT NO. 2 (this “Amendment No. 2”) is made effective August 26, 2021 (“Amendment No. 2 Effective Date”) and hereby amends that certain LICENSE, DEVELOPMENT, AND COMMERCIALIZATION AGREEMENT (collectively, with all amendments thereto, the “Agreement”), dated December 11, 2013, by and between NEOTOPE BIOSCIENCES LIMITED (as of January 5, 2015, PROTHENA BIOSCIENCES LIMITED, “Prothena Ireland”) with respect to all rights and obligations under this Agreement outside of the United States, and PROTHENA BIOSCIENCES INC (“Prothena US”) with respect to all rights and obligations under this Agreement in the United States (Prothena US, together with Prothena Ireland, “Prothena”), on the one hand, and F. HOFFMANN-LA ROCHE LTD (“Roche Basel”) with respect to all rights and obligations under this Agreement outside of the United States, and HOFFMANN-LA ROCHE INC. (“Roche Nutley”) with respect to all rights and obligations under this Agreement in the United States (Roche Nutley, together with Roche Basel, “Roche”), on the other hand. All capitalized terms used herein shall have the meaning ascribed herein or in the Agreement.

RECITALS

WHEREAS, Prothena and Roche are parties to the Agreement; and

WHEREAS, Prothena has requested and Roche has agreed to clarify certain provisions in the Agreement in accordance with the terms hereof.

NOW, THEREFORE, in consideration of the foregoing and the mutual agreements set forth below, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties hereby agree as follows:

1.The following new Section 1.14bis is hereby added to the Agreement:

1.14bis “Change of Control” means, with respect to a Party: (a) the acquisition by any Third Party of beneficial ownership of fifty percent (50%) or more of the then outstanding common shares or voting power of such Party, other than acquisitions by employee benefit plans sponsored or maintained by such Party; (b) the consummation of a business combination involving such Party, unless, following such business combination, the stockholders of such Party immediately prior to such business combination beneficially own directly or indirectly more than fifty percent (50%) of the then outstanding common shares or voting power of the entity resulting from such business combination; or (c) the sale of all or substantially all of such Party’s assets or business relating to the subject matter of the Agreement.

2.The following new Section 1.16bis is hereby added to the Agreement:

1.16bis “Collaboration Agreements” means (i) the Agreement, (ii) that certain License Agreement, dated March 1, 2020, by and between Prothena Biosciences Limited (f/k/a Neotope Biosciences Limited) and F. Hoffmann-La Roche Ltd (including, for the avoidance of doubt, as amended pursuant to that certain Understanding Related to License, Development and Commercialization Agreement, dated March 1, 2020, by and between Prothena Biosciences

Limited (f/k/a Neotope Biosciences Limited) and Prothena Biosciences Inc., on the one hand, and F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc., on the other hand), and (iii) that certain Sublicense Agreement, dated March 3, 2014, by and between Prothena Biosciences Limited (f/k/a Neotope Biosciences Limited), one the one hand, and F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc., on the other hand, in each case, as may be amended and/or restated from time to time.

3.The following new Section 18.13 is hereby added to the Agreement:

18.13 Exceptions for Change of Control. Notwithstanding anything to the contrary in the Collaboration Agreements, if, during the Term, Prothena Ireland, Prothena US and/or Prothena Corporation plc is acquired by or otherwise undergoes a Change of Control with a Third Party:

(a)such Third Party, its affiliates, and any persons or entities acquired by any such persons or entities following such Change of Control (each, an “Acquiror Entity”) shall have the right to conduct, participate in, or fund, directly or indirectly, alone or with a Third Party, research, development or commercialization activities specifically directed to any Antibody Products targeting Alpha-Synuclein (“Acquiror Programs”); provided that, subject to Section 18.13(b), no Prothena Technology or Roche Technology is used in such research, development or commercialization activities;

(b)any Patents, Information and other intellectual property owned by, licensed to, or otherwise Controlled by any Acquiror Entity (whether as of or following the Effective Date) (the “Acquiror IP”) shall not be included in the intellectual property rights licensed or with respect to which rights are granted, or ownership is assigned, to Roche or any of its Affiliates hereunder or pursuant to any Collaboration Agreement (and without limiting the foregoing, and for clarity, the Acquiror IP shall not be included in the Prothena Technology);

(c)the definition of Firewalled Entities in Section 3.1 of the Agreement shall be amended so that subsection (ii) reads as follows: (ii) any (A) Affiliate of Roche or (B) [***], which in the case of either (A) or (B) is subject to a firewall or similar mechanism designed to prevent the transfer of Information specifically directed to Antibody Products targeting Alpha-Synuclein between such Affiliate [***] who work on Antibody Products targeting Alpha-Synuclein under this Agreement; and

(d)Prothena’s membership in [***] Committees shall be [***] and Roche shall inform Prothena of its Development and Commercialization activities under the Agreement in report to be provided on or about the [***]; provided that, in respect of the foregoing (a) and (b), the personnel working on the day-day to activities under this Agreement (which, for clarity, does not include members of management and other personnel not involved in such day-to-day activities) are subject to a firewall or similar mechanism designed to prevent the transfer of Confidential Information from such personnel to personnel working on the day-day to activities for such Acquiror Programs, and further provided that such employees must have obligations that are no less protective of Roche than the obligations applicable to Prothena set forth herein, to prevent any unauthorized use or disclosure of Confidential Information of Roche or Roche Technology.

4.Prothena Affiliates. Without limiting Section 3.1 of the Agreement, for clarity, for purposes of Sections 12.2, 12.3(c), 16.6 and 16.7 of the Agreement, “Affiliates” of Prothena shall not include any Acquiror Entity.

5.Conflicts. For clarity, in the event of any conflict between the terms of this Amendment No. 2 and the Agreement or any other Collaboration Agreement, this Amendment No. 2 shall control.

6.Counterparts. This Amendment No. 2 may be executed in counterparts with the same effect as if both Parties had signed the same document. All such counterparts shall be deemed an original, shall be construed together, and shall constitute one and the same instrument. Any such counterpart, to the extent delivered by means of a fax machine or by .pdf, .tif, .gif, .jpeg or similar attachment to electronic mail (any such delivery, an “Electronic Delivery”) shall be treated in all manner and respects as an original executed counterpart and shall be considered to have the same binding legal effect as if it were the original signed version thereof delivered in person. No Party hereto shall raise the use of Electronic Delivery to deliver a signature or the fact that any signature or agreement or instrument was transmitted or communicated through the use of Electronic Delivery as a defense to the formation of a contract, and each Party forever waives any such defense, except to the extent that such defense relates to lack of authenticity.

7.Entire Agreement. This Amendment No. 2, together with the Collaboration Agreements, contains the entire agreement by the Parties with respect to the subject matter hereof and supersedes any prior express or implied agreements, understandings and representations, either oral or written, which may have related to the subject matter hereof in any way.

8.Severability. If any provision of this Amendment No. 2 shall be held invalid, illegal or unenforceable, such provision shall be enforced to the maximum extent permitted by law and the Parties’ fundamental intentions hereunder and the remaining provisions shall not be affected or impaired.

9.Governing Law. This Amendment No. 2 and all actions arising out of or in connection with this Amendment No. 2 shall be governed by and construed in accordance with the laws of the State of New York, without regard to its or any other jurisdiction’s conflict of law principles. Any disputes arising out of or relating to this Amendment No. 2 shall be resolved in accordance with Section 17 of the Agreement as if such dispute were a Dispute under the Agreement.

[Signature Page Follows]

IN WITNESS WHEREOF, the Parties have caused this Amendment No. 2 to be executed in duplicate as of the date written above by their duly authorized officers.

Prothena Biosciences Limited

By: /s/ Olivia Waldron
Name: Olivia Waldron
Title: Assistant Company Secretary

Prothena Biosciences Inc

By: /s/ Karin Walker
Name: Karin Walker
Title: Chief Accounting Officer

F. Hoffmann-La Roche Ltd

By: /s/ Barbara Schroeder de Castro Lopes
Name: Barbara Schroeder de Castro Lopes
Title: Authorized Signatory

By: /s/ Markus Keller
Name: Markus Keller
Title: Alliance Director

Hoffmann-La Roche Inc.

By: /s/ John P. Parise
Name: John P. Parise
Title:Authorized Signatory

Signature Page to Amendment No. 2

Exhibit 10.4

SHARE PURCHASE AGREEMENT

by and between

NOVO NORDISK A/S;

NOVO NORDISK REGION EUROPE A/S;

PROTHENA CORPORATION PLC;

and

PROTHENA BIOSCIENCES LIMITED

Dated as of July 8, 2021

Table of Contents

Page


SECTION 1. Description of Transaction			1
1.1 Purchase and Sale of Shares			1
1.2 Purchase Price			1
1.3 Closing			1
1.4 Payoff Letters			2
1.5 Withholding			2
1.6 Post Closing Adjustment to Closing Purchase Price			3
1.7 Contingent Consideration.			5
SECTION 2. Representations and Warranties of Seller			12
2.1 Due Incorporation; Etc			12
2.2 Assets of the Acquired Company.			12
2.3 Title to Shares; Capitalization, Etc			13
2.4 Financial Statements			14
2.5 Absence of Certain Changes			14
2.6 No Tangible Assets			14
2.7 Intellectual Property.			14
2.8 Regulatory Matters.			17
2.9 Material Contracts.			18
2.10 Liabilities			20
2.11 Compliance with Laws; Permits			20
2.12 Certain Business Practices			20
2.13 Tax Matters.			21
2.14 Employee Benefit Plans and Employee Matters			24
2.15 Insurance			25
2.16 Legal Proceedings; Orders			25
2.17 Authority; Binding Nature of Agreement			25
2.18 Non-Contravention; Governmental Consents			25
2.19 Financial Advisor			26
2.20 Intercompany Contracts			26
2.21 Solvency.			26
2.22 Powers of Attorney and Agency			27
2.23 Directors			27
SECTION 3. Representations and Warranties of Buyer			27
3.1 Due Incorporation; Subsidiaries			27
3.2 Authority; Binding Nature of Agreement			27
3.3 Non-Contravention; Consents			27
3.4 Litigation			28
3.5 No Buyer Vote Required			28
3.6 Availability of Funds			28


			i.

Table of Contents

(continued)

Page


SECTION 4. Certain Covenants of Seller			28
4.1 Access			28
4.2 Conduct of the Business of the Acquired Company			29
4.3 Exclusivity			31
SECTION 5. Additional Covenants of the Parties			31
5.1 Reasonable Best Efforts			31
5.2 Indemnification of Certain Persons			32
5.3 Disclosure			33
5.4 Tax Matters			33
5.5 Notification of Certain Events			37
5.6 Guaranty of Parent			37
SECTION 6. Conditions Precedent to Obligations of Buyer			38
6.1 Accuracy of Representations and Warranties			38
6.2 Performance of Covenants			38
6.3 No Restraints			38
6.4 Agreements and Documents			38
6.5 Closing Certificate			39
6.6 Company Material Adverse Effect.			39
6.7 Intercompany Contracts.			39
6.8 Transition Services Agreement.			39
SECTION 7. Conditions Precedent to Obligations of Seller			39
7.1 Accuracy of Representations and Warranties			40
7.2 Performance of Covenants			40
7.3 No Restraints			40
7.4 Closing Certificate			40
7.5 Transition Services Agreement.			40
SECTION 8. Indemnification			40
8.1 Indemnification of Buyer			40
8.2 Indemnification of Seller			41
8.3 Third-Party Claims			42
8.4 Indemnification Mechanics			43
8.5 Survival			44
8.6 Sole and Exclusive Remedy; Limitations			45
8.7 Mitigation of Losses			46
8.8 Provisions			46
8.9 Change of Law			47
8.10 Voluntary Acts			47
8.11 Treatment of Payments			47
8.12 Offset			47


			ii.

Table of Contents

(continued)

Page


SECTION 9. Termination			48
9.1 Termination			48
9.2 Effect of Termination			49
SECTION 10. Miscellaneous Provisions			49
10.1 Amendment			49
10.2 Expenses			49
10.3 Waiver			49
10.4 Entire Agreement; Counterparts			49
10.5 Applicable Law; Jurisdiction			49
10.6 Attorneys’ Fees			50
10.7 Assignability			50
10.8 Third Party Beneficiaries; No Recourse			50
10.9 Notices			51
10.10 Severability			52
10.11 Knowledge			53
10.12 Conflict of Interest			53
10.13 Attorney-Client Privilege			53
10.14 Acknowledgement			54
10.15 Specific Performance			54
10.16 Construction			55
10.17 Disclosure Schedule			55


			iii.

Table of Contents

(continued)

Certain schedules and exhibits have been omitted pursuant to Item 601(b)(2) of Regulation S-K. The Company agrees to furnish supplementally a copy of any omitted schedules or exhibits

Exhibits

Exhibit A - Certain Definitions

Exhibit B - Clinical Development Plan

Exhibit C - Form of Joint Press Release

Exhibit D - Form of Transition Services Agreement

Schedules

Disclosure Schedule

iv.

SHARE PURCHASE AGREEMENT

This Share Purchase Agreement (as may be amended from time to time, this “Agreement”) is made and entered into as of July 8, 2021 by and among: Novo Nordisk A/S, an entity organized under the laws of Denmark (“Novo Nordisk”); Novo Nordisk Region Europe A/S, an entity organized under the laws of Denmark (“NNRE” and together with Novo Nordisk, “Buyer”); Prothena Biosciences Limited, a private company limited by shares incorporated under the laws of Ireland with registered number 460227 (“Seller”); and Prothena Corporation Plc, a public company limited by shares incorporated under the laws of Ireland with registered number 518146 (“Parent”). Parent is a party to this Agreement solely for purposes of Section 5.6 (Guaranty of Parent). Certain capitalized terms used in this Agreement are defined in Exhibit A.

Recitals

A. Seller owns 100 ordinary shares, nominal value $1.00 per share, of Neotope Neuroscience Limited, a private company limited by shares incorporated under the laws of Ireland with registered number 660578 (the “Acquired Company”) (such shares, the “Shares”), which Shares constitute all of the issued and outstanding equity interests in the Acquired Company.

B. Seller desires to sell and transfer all of the Shares to NNRE, and NNRE desires to acquire all of the Shares from Seller, all on the terms and subject to the conditions set forth in this Agreement.

NOW, THEREFORE, in consideration of these premises, the covenants set forth herein and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties to this Agreement, intending to be legally bound, agree as follows:

SECTION 1.Description of Transaction

1.1Purchase and Sale of Shares. Upon the terms and subject to the conditions set forth in this Agreement, at the Closing, Seller shall sell, transfer and deliver to NNRE, free and clear of all Liens, and NNRE shall purchase from Seller, the Shares (the “Sale”).

1.2Purchase Price. Subject to Section 1.6 (Post Closing Adjustment to Closing Purchase Price) and Section 8.11 (Treatment of Payments), the consideration for the Sale pursuant to this Agreement will be the Purchase Price.

1.3Closing.

(a)The consummation of the transactions contemplated by this Agreement (the “Closing”) shall take place remotely via electronic exchange of required Closing documentation in lieu of an in-person Closing at 9:00 a.m. Dublin, Ireland time on a date to be mutually agreed on by the parties (the “Closing Date”), which shall be no later than the second Business Day after the satisfaction or waiver of the last to be satisfied or waived of the conditions set forth in Section 6 (Conditions Precedent to Obligations of Buyer) and Section 7 (Conditions Precedent to Obligations of Seller) (other than those

conditions that by their nature are to be satisfied at the Closing, but subject to the satisfaction or waiver of such conditions). Upon the occurrence of the Closing, the time and date that the transactions contemplated hereby become effective shall be 12:01 a.m. Dublin, Ireland time on the Closing Date.

(b)At the Closing, Buyer shall:

(i)pay an amount in cash equal to the Closing Purchase Price to Seller, by wire transfer of immediately available funds to an account of Seller specified in writing by Seller not less than three (3) Business Days prior to the Closing Date;

(ii)procure the payment on behalf of the Acquired Company of the Estimated Closing Date Indebtedness (and any penalties, premiums, fees and charges) to the applicable holder of such Debt, by wire transfer of immediately available funds to an account of such Debt holder specified in writing by Seller not less than three (3) Business Days prior to the Closing Date; and

(iii)pay the Estimated Closing Date Transaction Expenses to each applicable third-party payee of such Estimated Closing Date Transaction Expenses, by wire transfer of immediately available funds, to such third party in accordance with the instruction provided by such third party not less than three (3) Business Days prior to the Closing Date.

1.4Payoff Letters. Prior to the Closing, Seller shall obtain payoff letters for the Closing Date Indebtedness set forth in Section 1.4 of the Disclosure Schedule, in form and substance reasonably acceptable to Buyer, which shall provide the dollar amount and the payee of the applicable Closing Date Indebtedness required to be paid in order to fully pay off such Closing Date Indebtedness as of the Closing.

1.5Withholding. Buyer shall be entitled to deduct and withhold from any consideration payable hereunder, or other payment otherwise payable pursuant to this Agreement, the amounts required to be deducted and withheld under applicable Law. Any amounts so withheld shall be paid over to the appropriate Governmental Body. Buyer and Seller acknowledge that neither party expects any consideration or other payment payable hereunder to require deduction or withholding. If any consideration or other payment payable hereunder is required to be deducted or withheld pursuant to this Section, Buyer shall pay additional amounts to Seller to the extent necessary to ensure that Seller receives, after payment of all such Taxes, the amount specified in this Agreement provided, however, that Buyer shall not be obliged to pay any such additional amounts to Seller where Buyer can reasonably demonstrate that any such deduction or withholding arose (i) solely as a result of an act or transaction taken or entered into by Seller, including as a result of such amount being payable to a recipient resident in a jurisdiction other than Ireland or (ii) as a result of a change in Law after the date hereof. If any consideration or other payment payable hereunder is required to be deducted or withheld under this Section and such deduction or withholding arose as a result of circumstances described in the proviso to the prior sentence, any amount so deducted or withheld and paid over to a Governmental Body shall be treated as though it had been paid to Seller. Buyer and Seller will cooperate with respect to all documentation required by any taxing authority or reasonably

requested by Seller or Buyer to secure (i) a reduction in the rate of applicable withholding taxes or (ii) a position that withholding taxes are not applicable in the circumstances. As soon as practicable after any payment of Taxes by Buyer to a taxing authority pursuant to this Section 1.5, Buyer shall deliver to Seller the original or a certified copy of a receipt issued by such taxing authority evidencing such payment, a copy of the return reporting such payment or other evidence of such payment reasonably satisfactory to Seller.

1.6Post Closing Adjustment to Closing Purchase Price

(a)Not less than [***] Business Days prior to the Closing Date, Seller shall deliver to Buyer the Estimated Closing Statement. Upon the delivery of the Estimated Closing Statement, Seller shall (i) reasonably make available to Buyer and its representatives the work papers and other books and records used in preparing the Estimated Closing Statement (ii) make its representatives reasonably available to Buyer and its representatives to discuss Buyer’s comments to the Estimated Closing Statement and (iii) consider all reasonable comments in good faith.

(b)Within [***] following the Closing, Buyer shall prepare and deliver to Seller a written statement (the “Closing Statement”), setting forth in reasonable detail, Buyer’s good faith calculation of the Closing Purchase Price, including (i) the Closing Date Cash Amount, (ii) the Closing Date Indebtedness and (iii) the Closing Date Transaction Expenses. Following the Closing, Buyer shall provide to Seller and its representatives, reasonable access during regular business hours, in such a manner as to not interfere with the normal operation of Buyer or the Acquired Company (subject to the execution of customary work paper access letters, if requested), to work papers and books and records relating to the preparation of the Closing Statement and to the representatives of Buyer and the Acquired Company who are knowledgeable about the preparation of the Closing Statement, in each case, solely for the purpose of assisting Seller and its representatives in their review of the Closing Statement and the calculations contained therein.

(c)If Seller disagrees with the calculations in the Closing Statement, Seller shall notify Buyer of such disagreement in writing (the “Dispute Notice”) no later than the [***] after delivery of the Closing Statement. The Dispute Notice must set forth in reasonable detail (A) any item on the Closing Statement which Seller believes has not been prepared in accordance with this Agreement and Seller’s determination of the amount of such item and (B) Seller’s alternative calculation of the Closing Purchase Price, the Closing Date Cash Amount, the Closing Date Indebtedness or the Closing Date Transaction Expenses, as the case may be. The Dispute Notice shall include only disagreements based on mathematical errors or the failure of the Closing Purchase Price, the Closing Date Cash Amount, the Closing Date Indebtedness or the Closing Date Transaction Expenses to be calculated in accordance with this Section 1.6 (Post Closing Adjustment to Closing Purchase Price) and the definitions contained in this Agreement (including the inclusion or exclusion of items in the definition and the magnitude of the included or excluded items). Any item or amount that Seller does not dispute in the Dispute Notice within such period shall be final, binding and conclusive for all purposes hereunder.

(d)In the event any such Dispute Notice is timely provided, Buyer and Seller shall use commercially reasonable efforts for a period of [***] after the date of such Dispute Notice (or such longer period as they may mutually agree) to resolve any disagreements with respect to the calculations included in the Closing Statement that were disputed in the Dispute Notice. If, at the end of such [***] period (or such longer period as mutually agreed), Seller and Buyer remain unable to resolve the dispute in its entirety, then the unresolved items and amounts thereof in dispute shall be submitted to an internationally recognized financial services firm, reasonably acceptable to Buyer and Seller, which shall not be the independent accountants of Buyer or Seller (the “Dispute Auditor”). The Dispute Auditor shall determine, based solely on the provisions of this Section 1.6 (Post Closing Adjustment to Closing Purchase Price), Accounting Principles and the written presentations by Seller and Buyer, and not by independent review, only those items and amounts that remain then in dispute as set forth in the Dispute Notice.

(e)The Dispute Auditor’s determination of the Closing Purchase Price, the Closing Date Cash Amount, the Closing Date Indebtedness or the Closing Date Transaction Expenses, as applicable, shall be made within [***] after the dispute is submitted for its determination and shall be set forth in a written statement delivered to Seller and Buyer. A judgment of a court of competent jurisdiction selected pursuant to Section 10.5 (Applicable Law; Jurisdiction) hereof may be entered upon the Dispute Auditor’s determination, provided that no party shall make any filing to obtain such judgment unless (i) the payment required by such determination shall not have been made and (ii) [***] shall have elapsed following delivery of the Dispute Auditor’s determination, provided, further, that any filing to obtain such judgment shall respect the confidential nature of the dispute resolution process provided in this Section 1.6 (Post Closing Adjustment to Closing Purchase Price) and shall disclose the details of the dispute only to the extent necessary to obtain a judgment. The Dispute Auditor shall have exclusive jurisdiction over and, resorting to the Dispute Auditor as provided in this Section 1.6 (Post Closing Adjustment to Closing Purchase Price), shall be the only recourse and remedy of the parties against one another with respect to, those items and amounts that remain in dispute under this Section 1.6 (Post Closing Adjustment to Closing Purchase Price), and Buyer shall not be entitled to seek indemnification or recovery of any attorneys’ fees or other professional fees incurred by Buyer in connection with any dispute governed by this Section 1.6 (Post Closing Adjustment to Closing Purchase Price). The Dispute Auditor shall allocate its fees and expenses between Buyer and Seller according to the degree to which the positions of the respective parties are not accepted by the Dispute Auditor.

(f)Seller and Buyer shall, and shall cause their respective Affiliates and representatives to, cooperate in good faith with the Dispute Auditor, and shall give the Dispute Auditor access to all data and other information it reasonably requests for purposes of such resolution. In no event shall the decision of the Dispute Auditor assign a value to any item greater than the greatest value for such item claimed by either Buyer or Seller or lesser than the smallest value for such item claimed by either Buyer or Seller. Any determinations made by the Dispute Auditor pursuant to this Section 1.6 (Post Closing Adjustment to Closing Purchase Price) shall be final, non-appealable and binding on the parties hereto, absent manifest error or common law fraud.

(g)“Adjustment Amount” shall mean the net amount, which may be positive or negative, equal to: (i) (a) the Closing Date Cash Amount (as finally determined in accordance with this Section 1.6 (Post Closing Adjustment to Closing Purchase Price)); minus (b) the Estimated Closing Date Cash Amount; plus (ii) (a) the Estimated Closing Date Indebtedness; minus (b) the Closing Date Indebtedness (as finally determined in accordance with this Section 1.6 (Post Closing Adjustment to Closing Purchase Price)); plus (iii) (a) the Estimated Closing Date Transaction Expenses; minus (b) the Closing Date Transaction Expenses (as finally determined in accordance with this Section 1.6 (Post Closing Adjustment to Closing Purchase Price)); provided [***]. If the Adjustment Amount is a positive number, then within [***] after the final determination of the Adjustment Amount, Buyer shall pay the Adjustment Amount in cash to Seller by wire transfer of immediately available funds to an account specified in writing by Seller.

If the Adjustment Amount is a negative number, then within [***] after the final determination of the Adjustment Amount, Seller shall pay the absolute value of the Adjustment Amount in cash to Buyer by wire transfer of immediately available funds to an account specified in writing by Buyer.

No line item included in the calculation of the Closing Date Cash Amount, the Closing Date Indebtedness and the Closing Date Transaction Expenses shall be duplicative of any other line item included in such other calculations.

1.7Contingent Consideration.

(a)If the Closing shall have occurred, then (i) no more than [***] after the achievement of each of the milestone events set forth in Table I below with respect to a PRX004 Milestone Product by a Milestone Obligor (each, a “Development and Commercialization Milestone Event”) and (ii) within [***] after the end of each calendar quarter in which each milestone event set forth in Table II below is achieved with respect to a Milestone Product by a Milestone Obligor (each, a “Net Sales Milestone Event” and together with the Development and Commercialization Milestone Events, each a “Milestone Event” and collectively the “Milestone Events”), in each case, (A) Buyer shall notify Seller that such Milestone Event has been achieved (each such notice, a “Milestone Notice”) and (B) as partial consideration for the purchase and sale of the Shares pursuant to this Agreement, Buyer shall pay the milestone payment corresponding to such Milestone Event (each, a “Milestone Payment,” and, collectively, the “Milestone Payments”) in cash to Seller by wire transfer of immediately available funds to an account specified by Seller, in each case, subject to [***]. All Milestone Payments will be made in United States dollars, and the rate of exchange to be used in converting Net Sales made in other currencies into United States dollars will be the average of the daily exchange rates for the calendar quarter in which the applicable sales were made as such daily exchange rate is published in the U.S. east coast edition of The Wall Street Journal. For clarity, if more than one Net Sales Milestone Event is achieved in the same calendar quarter (and where such Net Sales Milestone Events have not been previously achieved), all Milestone Payments corresponding to such Net Sales Milestone Events achieved in such calendar quarter shall be paid by Buyer in aggregate. In the event Development and Commercialization Milestone Event #3 or Development and Commercialization

Milestone Event #4 in Table I below is achieved prior to Buyer paying the Milestone Payment corresponding to Development and Commercialization Milestone Event #1 and/or Development and Commercialization Milestone Event #2 in Table I below, then Development and Commercialization Milestone Event #1 and/or Development and Commercialization Milestone Event #2, as applicable, shall be deemed to have been achieved and such unpaid Milestone Payment corresponding to Development and Commercialization Milestone Event #1 and/or Development and Commercialization Milestone Event #2, as applicable, shall become due and payable in addition to and concurrently with the Milestone Payment corresponding to Development and Commercialization Milestone Event #3 or Development and Commercialization Milestone Event #4, as applicable. In the event that a Milestone Obligor [***] prior to Buyer paying the Milestone Payment corresponding to Development and Commercialization Milestone Event [***] in Table I below, then Development and Commercialization Milestone Event [***] shall be deemed to have been achieved and such unpaid Milestone Payment corresponding to Development and Commercialization Milestone Event #2 shall become due and payable within [***] of such Initiation. For clarity, in the event that a Milestone Obligor [***] of a PRX004 Milestone Product that satisfies [***], then Development and Commercialization Milestone Event [***] in Table I below shall become due and payable within [***] of such [***] if it was not paid prior to such [***]. If the first achievement of a Development and Commercialization Milestone Event is with respect to the [***], Buyer shall pay the applicable Milestone Payment as set forth in Table I and shall not have any further payment obligations hereunder on account of the subsequent achievement of such Development and Commercialization Milestone Event with respect to any [***] or by any other [***]. If the first achievement of a Development and Commercialization Milestone Event is with respect to an [***], Buyer shall pay the applicable Milestone Payment corresponding to such Development and Commercialization Milestone Event under the heading [***] as set forth in Table I and if the same Development and Commercialization Milestone Event is subsequently achieved for the [***], then Buyer shall pay to Seller an amount equal to [***]; after such payment, Buyer shall not have any further payment obligations hereunder on account of the subsequent achievement of such Development and Commercialization Milestone Event with respect to any [***] or by any other [***] (it being understood that if the first achievement of any Development and Commercialization Milestone Event is with respect to the [***], no Milestone Payment will be payable for any achievement of such Development and Commercialization Milestone Event with respect to any [***]). As an example, [***]. Notwithstanding anything in this Agreement to the contrary, (i) the maximum aggregate amount of Milestone Payments that Buyer and any other Milestone Obligor shall be obligated to pay shall be $1,170,000,000.00, (ii) each Net Sales Milestone Payment shall be paid only with respect to the first Milestone Product to achieve such Net Sales Milestone Event, (iii) no Milestone Payment for any Development and Commercialization Milestone Event shall be payable more than one time with respect to the ATTR Indication or any Other Indication and (iv) the maximum aggregate amount of the Milestone Payment for (A) Development and Commercialization Milestone Event #1 is [***], (B) Development and Commercialization Milestone Event #2 is [***], (C) Development and Commercialization Milestone Event #3 is [***], (D) Development and Commercialization Milestone Event #4 is [***] and (E) Development and

Commercialization Milestone Event #5 is [***] (it being understood that no Milestone Payment shall be due for any subsequent or repeated achievements of any Milestone Event with respect to the ATTR Indication or any Other Indication, as applicable, even if the same Milestone Event is achieved by more than one Milestone Product or achieved multiple times by the same Milestone Product). The parties acknowledge and agree that it is possible that, without any breach of this Agreement, any or all of the Milestone Events may not be [***] achieved, in which case any or all of the Milestone Payments may not be paid.

Table I


Milestone Number	Development and Commercialization Milestone Event	Milestone Payment (ATTR Indication)	Milestone Payment (Other Indication)
1	[***]	$[***]	$[***]
2	[***]	$[***]	$[***]
3	[***]	$[***]	$[***]
4	[***]	$[***]	$[***]
5	[***]	$[***]	$[***]

Table II


Milestone Number	Net Sales Milestone Event	Milestone Payment
6	First achievement of Annual Net Sales of any Milestone Product worldwide of at least $[***]	$[***]
7	First achievement of Annual Net Sales of any Milestone Product worldwide of at least $[***]	$[***]
8	First achievement of Annual Net Sales of any Milestone Product worldwide of at least $[***]	$[***]
9	First achievement of Annual Net Sales of any Milestone Product worldwide of at least $[***]	$[***]

(b)Commencing upon the Closing, Buyer and the other Milestone Obligors shall have the right, in their sole and absolute discretion, to direct and control the research, development, commercialization and other exploitation of all Milestone Products in all respects, including the determination to test, develop, pursue, market, make any regulatory filings with respect to, or make any strategic decisions affecting, such Milestone Products; provided that, commencing upon the Closing and continuing until the achievement of the [***], Buyer shall, and shall cause each Milestone Obligor to, act in good faith and with fair dealing and use Diligent Efforts to develop and achieve the [***] (it being understood that, notwithstanding anything in this Agreement to the contrary, in no event shall Buyer or any other Milestone Obligor be liable for any failure to perform any of its obligations under this Section 1.7(b) (Contingent Consideration) solely as a result of [***]. For the avoidance of doubt, the parties intend the express provisions of this Section 1.7(b) (Contingent Consideration) to govern their contractual obligations with respect to the rights and obligations under this Section 1.7(b) (Contingent Consideration) and to supersede any standard of efforts or implied covenant of good faith and fair dealing that might otherwise be imposed by applicable Law with respect thereto.

(c)If the Milestone Obligors, taken as a whole, cease performance of (i) [***] material development or commercialization activities with respect to all PRX004 Milestone Products for the [***] or (ii) [***] material activities set forth under the [***], then Buyer shall, or shall cause the applicable Milestone Obligor to, send written notice of each such cessation to Seller together with a detailed explanation for such cessation of activities. Buyer’s or the applicable Milestone Obligor’s satisfaction of its obligations pursuant to the foregoing sentence shall not relieve Buyer or such Milestone Obligor of

the obligation to act in good faith and use Diligent Efforts as set forth in Section 1.7(b) (Contingent Consideration)

(d)For so long as the Milestone Payments for any Development and Commercialization Milestone Events may become payable, Buyer shall, and shall cause each Milestone Obligor to, keep and maintain reasonable documentation substantiating its efforts to achieve such Milestone Events, and within [***] after the end of each of the [***] and [***] in each calendar year, Buyer shall, and shall cause each Milestone Obligor to, provide a written report to Seller in reasonable detail regarding the status of efforts to achieve such Development and Commercialization Milestone Events (each such report, an “Update Report”). If Seller requests a meeting with Buyer to discuss any Update Report within [***] after receipt thereof, Buyer shall make available for such a meeting such of its and the applicable Milestone Obligor’s respective employees and representatives with appropriate expertise and knowledge of the activities undertaken to perform the Clinical Development Plan, develop and commercialize PRX004 Milestone Products in [***] and achieve the Development and Commercialization Milestone Events. In addition, for [***] following Seller’s receipt of an Update Report, Buyer shall, and shall cause Milestone Obligors to, make available a qualified, designated employee with appropriate expertise and access to relevant information to respond telephonically or electronically to questions posed by Seller concerning the Update Report.

(e)Commencing with the calendar quarter in which the [***], within [***] after the end of each calendar quarter until all Milestone Payments corresponding to the Net Sales Milestone Events have been paid pursuant to Section 1.7(a) (Contingent Consideration), Buyer shall deliver to Seller a report setting forth, on a Milestone Product-by-Milestone Product, [***] (each such report, a “Sales Report”). Buyer shall, and shall cause each Milestone Obligor to, maintain complete and accurate books and records in reasonably sufficient detail to permit Seller to confirm the accuracy of the Sales Reports. Commencing with the calendar year in which the [***] occurs, upon the written request of Seller not more than one time during any calendar year, Seller shall have the right, at Seller’s expense, to have [***] be provided access during normal business hours, upon reasonable prior written notice, to such books and records of Buyer and each other Milestone Obligor as may be required to verify the accuracy of any Sales Report. Buyer shall, and shall cause each Milestone Obligor to, assist such [***] in conducting such audit, without charge, and shall make such books and records available for inspection and copying. Any and all records examined by such [***] shall be deemed to be confidential information of the audited Person, and, prior to providing such [***] with such access, the audited Person and such [***] shall have entered into a customary confidentiality agreement which shall provide, among other customary obligations, that any and all audited records shall not be disclosed by such independent certified public accounting firm to any third party [***] (except for the information expressly sought to be confirmed [***] as set forth in this Section 1.7(e) (Contingent Consideration)). If, based on the results of any audit conducted under this Section 1.7(e) (Contingent Consideration), it is determined pursuant to the terms of this Agreement that a Net Sales Milestone Event was achieved prior to the initiation of such audit and Buyer failed to provide a Milestone Notice to Seller in accordance Section 1.7(a) (Contingent

Consideration) with respect to such Net Sales Milestone Event, then Buyer shall make the Milestone Payment corresponding to such Net Sales Milestone Event, plus interest from the original due date as provided in Section 1.7(j) (Contingent Consideration) to Seller by wire transfer of immediately available funds to an account specified by Seller, within [***] after the [***] written report is delivered to Seller and to Buyer, to the extent not already paid, and [***]. If, based on the results of any audit conducted under this Section 1.7(e) (Contingent Consideration), it is determined pursuant to the terms of this Agreement that no such failure to provide a Milestone Notice occurred, [***].

(f)After the Closing until the date on which all Milestone Payments have been made, Buyer (or a Milestone Obligor) may divest (by way of merger, consolidation, asset acquisition or sale, exclusive license, assignment or other similar transfer) to a third party (the “Transferee”) all or substantially all of the Acquired Company’s right, title and interest in and to any Milestone Product and all Intellectual Property related to such Milestone Product and Buyer shall have no further obligations, responsibilities or liability under Section 1.7(f) (Contingent Consideration) with respect to such divested Milestone Product if [***]. Buyer shall provide Seller with copies of the divestiture documents within 30 days after execution, which copies may be redacted to remove information not required for Seller’s confirmation that the applicable conditions set forth in this Section 1.7(f) (Contingent Consideration) have been satisfied. For clarity, nothing in this Section 1.7(f) (Contingent Consideration) shall be construed as preventing or otherwise limiting Buyer from divesting, transferring, selling, licensing, conveying or otherwise disposing of any of its rights, title or interests in or to any Milestone Product or any Intellectual Property relating thereto; provided that Buyer shall remain primarily responsible for the obligations in this Section 1.7 (Contingent Consideration) following any divestiture, transfer, sale, license, conveyance or disposal of any Milestone Product or Intellectual Property relating thereto if the applicable conditions set forth in this Section 1.7(f) (Contingent Consideration) are not satisfied.

(g)Seller (i) shall, for a period of [***] from receipt by Seller, treat all information provided to it pursuant to this Section 1.7 (Contingent Consideration) (including information contained in any Update Report or Sales Report) as if it were confidential documents and information concerning the Acquired Company in accordance with Section 4.1(b) (but subject to the terms, limitations and exceptions of Sections 4.1(b) and 4.1(c)), and (ii) shall not use such information other than to assess the progress towards and the likelihood of achieving the Milestone Events, to determine Buyer’s compliance with its obligations pursuant to this Section 1.7 (Contingent Consideration) or enforce Seller’s rights pursuant to this Section 1.7 (Contingent Consideration) including the right to receive Milestone Payments corresponding to Milestone Events.

(h)If Seller in good faith believes that a Milestone Obligor is breaching any of its obligations under this Section 1.7 (Contingent Consideration), then Seller may provide Buyer with written notice thereof and provide reasonable detail regarding such alleged breaches. Buyer shall designate representatives, including at least one officer of Buyer or the applicable Milestone Obligor with operating responsibility for the applicable Milestone Products and appropriate expertise, to meet with Seller within [***] from the

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date of such notice to address in good faith Seller’s belief that such Milestone Obligor is breaching one or more obligations under Section 1.7 (Contingent Consideration). Buyer shall, and shall cause the Milestone Obligors to, work together with Seller to schedule an in-person meeting, if reasonably feasible, at a mutually acceptable location, or will schedule one or more conference calls to address the asserted breach of obligations, and Buyer and Seller shall endeavor in good faith to resolve any dispute. If no such resolution is reached during the [***] period following the date of Seller’s notice, then Seller shall be entitled to pursue all remedies available to it under this Agreement or otherwise under Law or equity with respect to such matter (in each case subject to and in accordance with the terms and limitations set forth in this Agreement, including Section 10.5 (Applicable Law; Jurisdiction)).

(i)The right of Seller to receive Milestone Payments: (i) does not give Seller dividend rights, voting rights, liquidation rights, preemptive rights or other rights of holders of shares of the Acquired Company; (ii) shall not be evidenced by a certificate or other instrument; (iii) other than pursuant to a Permitted Transfer, shall not be assignable or otherwise transferable by Seller; and (iv) does not represent any right other than the right to receive the consideration set forth in this Section 1.7 (Contingent Consideration). Any attempted transfer (other than a Permitted Transfer) of the right to the Milestone Payments by any holder thereof (other than as specifically permitted by the immediately preceding sentence) shall be null and void.

(j)Any Milestone Payment that is not paid on or before the date such payment is due under this Agreement will bear interest at the lower of (i) an annual rate equal to the prime rate (as published in The Wall Street Journal in effect on the date such payment was required to be made) plus [***], calculated on the total number of days payment is delinquent and (ii) the maximum rate allowed by applicable Law. Interest will accrue beginning on the first day following the due date for payment. Payment of such interest by Buyer shall not limit, in any way, Seller’s rights to exercise any other remedies it may have as a consequence of the lateness of any payment.

SECTION 2.Representations and Warranties of Seller

Seller represents and warrants to Buyer, except as set forth in the Disclosure Schedule, as follows:

2.1Due Incorporation; Etc.

(a)Each of Seller and the Acquired Company is a private company limited by shares incorporated under the laws of Ireland and is duly organized and validly existing under the laws of Ireland and has all necessary corporate power and authority to conduct its business in the manner in which its business is currently being conducted. Seller has delivered or otherwise made available to Buyer or its representatives true and correct copies of the constitution and certificate of incorporation of each of Seller and the Acquired Company, and in the case of the Acquired Company, including all amendments thereto, as in effect on the date hereof, which documents are in full force and effect as of the date hereof.

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(b)Seller is duly qualified or licensed to do business and, where applicable as a legal concept, is in good standing in each jurisdiction where the character of the properties owned, leased or licensed by it or the nature of its business and activities makes such qualification, licensing or good standing necessary, except where the failure to be so qualified or licensed or in good standing has not had or would not reasonably be expected to prevent or materially impair or materially delay the ability of Seller to perform its obligations under this Agreement. The Acquired Company is duly qualified or licensed to do business and, where applicable as a legal concept, is in good standing in each jurisdiction where the character of the properties owned, leased or licensed by it or the nature of its business and activities makes such qualification, licensing or good standing necessary, except where the failure to be so qualified or in such good standing has not had and would not reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect.

2.2Assets of the Acquired Company.

(a)The Acquired Company was formed on November 13, 2019. [***] Since October 1, 2020, the Acquired Company has solely engaged in the business of developing the Compound and PRX004 Milestone Product (the “Business”). The Acquired Company has not engaged in any business activities, conducted any operations, or incurred, directly or indirectly, any obligation or liability of any type or kind whatsoever, or entered into any Contract with any Person, in each case other than in connection with [***] or the Business.

(b)Except as set forth in Section 2.2(b) of the Disclosure Schedule, the Acquired Company exclusively owns or licenses from third parties all of the property, assets and rights owned, licensed or held for use by any member of the Parent Group in or for the Business as currently conducted prior to the Closing, free and clear of any Liens, other than Permitted Encumbrances and no member of the Parent Group (other than the Acquired Company) has any right, title or interest in or to the Compound or any Milestone Product.

(c)The Acquired Company does not (i) have any Subsidiaries or (ii) own or control, directly or indirectly, any equity interests in any other Person.

2.3Title to Shares; Capitalization, Etc.

(a)Seller is the legal and beneficial owner of, and has good and valid title to, the Shares, free and clear of any Liens. The Shares comprise of the whole of the allotted and issued share capital of the Acquired Company.

(b)The authorized share capital of the Acquired Company consists of ordinary shares, nominal value $1.00 per share, of which 100 shares are issued and outstanding and legally and beneficially held by Seller. All of the Shares are duly authorized, validly issued and are fully paid and nonassessable, and have not been issued in violation of any preemptive rights. The Acquired Company does not hold any treasury shares.

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(c)Other than the Shares, (i) there are no other existing options, warrants, calls, rights (whether actual or contingent and including conversion rights, preemptive rights, co-sale rights, rights of first refusal or other similar rights) or agreements to which the Acquired Company or Seller is a party requiring, and there are no securities of the Acquired Company outstanding which upon conversion or exchange would require, the issuance, allotment, sale or transfer of any additional shares of the Acquired Company or other equity securities of the Acquired Company or other securities convertible into, exchangeable for, or evidencing the right to subscribe for or purchase, shares of the Acquired Company or other equity securities of the Acquired Company, (ii) there are no obligations, contingent or otherwise, of the Acquired Company to repurchase, redeem or otherwise acquire any shares of the Acquired Company and (iii) there are no outstanding stock appreciation, phantom stock, profit participation or similar rights with respect to the Acquired Company. There are no bonds, debentures, notes or other Debt of the Acquired Company having the right to vote or consent (or convertible into, or exchangeable for, securities having the right to vote or consent) on any matters on which Seller may vote. There are no voting trusts, irrevocable proxies or other Contracts or understandings to which the Acquired Company or Seller is a party or is bound with respect to the voting or consent of any shares of the Acquired Company.

2.4Financial Statements. Seller has delivered or otherwise made available to Buyer or its representatives true and correct copies of (a) the Acquired Company’s audited financial statements for the year ended December 31, 2020 (the “Audited Financial Statements”) and (b) the unaudited balance sheet of the Acquired Company as of May 31, 2021 (the “Unaudited Balance Sheet,” and such date, the “Balance Sheet Date”), and unaudited statement of operations as of May 31, 2021 (all of the foregoing financial statements of the Acquired Company and any notes thereto are hereinafter collectively referred to as the “Company Financial Statements”). The Company Financial Statements were prepared in accordance with IFRS and fairly present in all material respects the financial condition of the Acquired Company at the dates therein indicated and the results of operations of the Acquired Company for the periods therein specified in accordance with IFRS, except that the unaudited financial statements do not contain footnotes and are subject to normal year-end adjustments.

2.5Absence of Certain Changes. Since the Balance Sheet Date through the date of this Agreement, (a) there has not occurred any event, development or series of related events that has had or would reasonably be expected to have, individually or in the aggregate, a Company Material Adverse Effect and (b) except as contemplated by this Agreement and for discussion, negotiations and transactions related to this Agreement or other potential strategic transactions, the Acquired Company has operated its business in the ordinary course of business in all material respects and has not taken any action that, if taken after the date of this Agreement and without Buyer’s consent, would constitute a material breach of Sections 4.2(a) through 4.2(q) (Conduct of the Business of the Acquired Company).

2.6No Tangible Assets. Except as set forth in Section 2.6 of the Disclosure Schedule, the Acquired Company does not own, and does not have any leasehold interest in, any tangible assets, including real property.

2.7Intellectual Property.

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(a)Section 2.7(a) of the Disclosure Schedule identifies a true, correct and complete list of: (i) each item of Registered IP (A) included in the Company Intellectual Property or (B) included in the Company Licensed Intellectual Property that is exclusively licensed to the Acquired Company; and (ii) the jurisdiction in which such item of Registered IP has been registered or filed and the applicable registration, application or serial number. None of such Registered IP, to Seller’s Knowledge with respect to such Registered IP that is included in the Company Licensed Intellectual Property, has been adjudged invalid or unenforceable and, to Seller’s Knowledge, each such item of Registered IP is valid, subsisting, and enforceable other than such items that are applications that have not been granted, issued or registered, as applicable.

(b)To Seller’s Knowledge, there is no Intellectual Property owned by any third party (including any member of the Parent Group that is not the Acquired Company) that (i) is valid and enforceable, (ii) is required to conduct the Business as currently conducted and (iii) the Acquired Company is not currently authorized to use. The Company Intellectual Property and Company Licensed Intellectual Property constitute all Intellectual Property owned by or licensed to Seller or any member of the Parent Group, as of the Closing that Covers the Compound or the PRX004 Milestone Product that was the subject of the phase 1 clinical trial completed by the Acquired Company in 2020 (as such Compound and PRX004 Milestone Product exist as of the Closing) or that is otherwise necessary to, or used or held for use in, the conduct of the Business as currently conducted.

(c)To Seller’s Knowledge, neither the Acquired Company nor the conduct of the Business as currently conducted infringes, misappropriates or otherwise violates nor the Acquired Company’s prior conduct of the Business infringed, misappropriated or otherwise violated, any Intellectual Property rights of any third parties. No Person has asserted any written claim, or to Seller’s Knowledge, any oral claim, and there is no Legal Proceeding pending, or to Seller’s Knowledge, threatened, against the Acquired Company (i) challenging the Acquired Company’s right, interest or title in any of the Company Intellectual Property or, to Seller’s Knowledge, Company Licensed Intellectual Property or the validity or enforceability of such Company Intellectual Property or, to Seller’s Knowledge, any Company Licensed Intellectual Property or (ii) alleging any infringement, misappropriation or other violation of any third party Intellectual Property by the Acquired Company or the conduct of the Business. None of the Company Intellectual Property, and to the Seller’s Knowledge, the Company Licensed Intellectual Property, is subject to any pending or outstanding injunction, directive, order, judgment, or other disposition of dispute that adversely restricts the use, transfer, registration or licensing of any such Company Intellectual Property, or to Seller’s Knowledge, Company Licensed Intellectual Property, by the Acquired Company. The consummation of the transactions contemplated by this Agreement will not alter, encumber, impair or extinguish any Company Intellectual Property or, to Seller’s Knowledge, any Company Licensed Intellectual Property. The representations and warranties in Sections 2.7(b) and 2.7(c) (Intellectual Property) are the only representations and warranties by Seller with respect to the infringement or alleged infringement by the Acquired Company of the Intellectual Property of any third party.

14.

(d)To Seller’s Knowledge, no Person has infringed, misappropriated or otherwise violated, and no Person is currently infringing, misappropriating or otherwise violating any material (i) Company Intellectual Property or (ii) Company Licensed Intellectual Property exclusively licensed to the Acquired Company.

(e)Section 2.7(e)(i) of the Disclosure Schedule identifies each Contract pursuant to which the Acquired Company is a licensee of, or is otherwise granted any rights to use or any covenant to be sued under, any Intellectual Property owned by any third party that is used or held for use in the Business (other than (i) non-disclosure or material transfer Contracts, (ii) Contracts between the Acquired Company and its employees or consultants, (iii) non-exclusive licenses to off-the-shelf, commercially available third party software with annual license maintenance or other fees of $[***] or less in the aggregate, (iv) any Contract in connection with purchases of assays or other laboratory consumables, (v) clinical trial Contracts and (vi) immaterial Contracts for provision by a third party of research services, including preclinical services, in the case of each of clauses (i)-(vi), entered into in the ordinary course of business). Section 2.7(e)(ii) of the Disclosure Schedule identifies each Contract material to the Business pursuant to which the Acquired Company is a licensor of, or otherwise grants to any third party any rights to use or any covenant not to sue under, any Company Intellectual Property or Company Licensed Intellectual Property (other than non-exclusive licenses entered into in the ordinary course of business).

(f)Except as set forth in Section 2.7(f) of the Disclosure Schedule, the Acquired Company is the sole and exclusive owner of all Company Intellectual Property, free and clear of any Liens, other than Permitted Encumbrances or licenses that are set forth in Section 2.7(e)(ii) of the Disclosure Schedule or are not required to be listed therein, and holds a legal and valid license to all material Company Licensed Intellectual Property. As of the Closing, except for the Acquired Company, no Person that is an Affiliate of the Acquired Company as of immediately prior to the Closing (including Parent and its Subsidiaries) shall have any right, title or interest in or to any quantities of the Compound or any PRX004 Milestone Product then in existence or (i) any Company Intellectual Property or (ii) any Company Licensed Intellectual Property that is specific to the Compound or that is exclusively licensed to the Acquired Company. The Acquired Company has not granted to any Person any license (including any sublicense), option, or other right, title or interest (including any right of first refusal or other preferential right or covenant not to sue or other immunity) in or to, or assigned or otherwise transferred to any Person, any Company Intellectual Property or Company Licensed Intellectual Property for the purpose of permitting such Person to commercialize the Compound or any Milestone Product.

(g)To Seller’s Knowledge, in relation to the Acquired Company’s collection, use, or disclosure of any personally identifiable information in the possession or control of the Acquired Company (including Personal Data) in connection with the conduct of the Business or otherwise, the Acquired Company has taken commercially reasonable security measures against unauthorized access to, unauthorized alterations, disclosure or destruction of, or access to any such personally identifiable information transmitted, stored or processed by the Acquired Company and has complied in all

15.

material respects with (i) all governing Laws (including applicable Data Protections Laws), (ii) the Acquired Company’s written and published privacy policies or notices, and (iii) contractual obligations by which the Acquired Company is bound. To Seller’s Knowledge, there are no complaints to, or audits, proceedings, investigations or claims pending against, the Acquired Company by any Governmental Body, or by any Person, in respect of the Acquired Company’s collection, use or disclosure of personally identifiable information (including Personal Data) of any Person in connection with the conduct of the Business. To Seller’s Knowledge, the Acquired Company has not suffered a breach of or other unauthorized access to personally identifiable information in the Acquired Company’s possession that compromised the privacy or security of such personally identifiable information.

(h)The Acquired Company has used commercially reasonable efforts to protect the secrecy and confidentiality of all Company Intellectual Property and Company Licensed Intellectual Property, in each case the value of which is contingent on maintaining the confidentiality thereof, and to the Seller’s Knowledge, no such Company Intellectual Property or Company Licensed Intellectual Property has been disclosed by the Acquired Company other than to Persons bound by valid, binding and enforceable written confidentiality agreements. All current and former employees, consultants and independent contractors of the Acquired Company and any other Person who is or was involved in the creation or development by or on behalf of the Acquired Company of any Intellectual Property for or on behalf of the Business have entered into valid, binding and enforceable written agreements with the Acquired Company or its Affiliates pursuant to which such Person has assigned to the Acquired Company or its Affiliate all Intellectual Property conceived, reduced to practice, authored, developed or otherwise created by such Person in the course of such Person’s employment by the Acquired Company or performance of services on behalf of the Acquired Company, all in accordance with all applicable Laws, and, to the extent that such Intellectual Property was assigned to an Affiliate of the Acquired Company, such Affiliate assigned such Intellectual Property to the Acquired Company.

(i)Except as set forth in Section 2.7(i) of the Disclosure Schedule, no Governmental Body or academic institution has any right to, ownership of, or right to royalties for, any Company Intellectual Property or, to the Seller’s Knowledge, any Company Licensed Intellectual Property that is exclusively licensed to the Acquired Company.

1.8Regulatory Matters.

(a)The Acquired Company has filed with the applicable regulatory authorities (including the FDA or any other Governmental Body performing functions similar to those performed by the FDA) all required material filings, declarations, listings, registrations, reports or submissions, including adverse event reports for its business as currently being conducted. All such filings, declarations, listings, registrations, reports or submissions were in material compliance with applicable Laws when filed, and no deficiencies have been asserted by any applicable Governmental Body with respect to any such filings, declarations, listing, registrations, reports or submissions.

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(b)Except as would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect, all preclinical and clinical investigations sponsored by the Acquired Company are being conducted in compliance with applicable Laws, rules, regulations and guidances, including Good Clinical Practices requirements and federal and state Laws, rules, regulations and guidances restricting the use and disclosure of individually identifiable health information. As of the date of this Agreement, the Acquired Company has not received any written notices or other correspondence from the FDA or any other Governmental Body performing functions similar to those performed by the FDA with respect to any ongoing clinical or preclinical studies or tests requiring the termination, suspension or material modification of such studies or tests.

(c)The Acquired Company has not (i) made an untrue statement of a material fact or fraudulent statement to the FDA or any Governmental Body, (ii) failed to disclose a material fact required to be disclosed to the FDA or any Governmental Body or (iii) committed any other act, made any statement or failed to make any statement, that (in any such case) establishes a reasonable basis for the FDA to invoke its Fraud, Untrue Statements of Material Facts, Bribery, and Illegal Gratuities Final Policy or for any other Governmental Body to invoke a similar policy. As of the date of this Agreement, the Acquired Company and the Business are not the subject of any pending or, to Seller’s Knowledge, threatened investigation by the FDA pursuant to its Fraud, Untrue Statements of Material Facts, Bribery, and Illegal Gratuities Final Policy. The Acquired Company has not been, and, to Seller’s Knowledge, no agent or clinical investigator of the Acquired Company has been, suspended or debarred or convicted of any crime or engaged in any conduct that would reasonably be expected to result in (a) debarment under 21 U.S.C. Section 335a or any similar Law or (b) exclusion under 42 U.S.C. Section 1320a-7 or any similar Law.

2.9Material Contracts.

(a)Section 2.9(a) of the Disclosure Schedule lists each Contract in effect as of the date of this Agreement to which the Acquired Company is a party in the following categories (other than (1) clinical trial Contracts and material transfer Contracts in the ordinary course of business, (2) any Contract concerning non-exclusive rights to “off-the-shelf” or similar software or to other technology that is unmodified and generally available on commercially reasonable terms with annual license, maintenance or other fees of $[***] or less in the aggregate, (3) any Contract that is terminable without penalty by any other party thereto on 90 days’ or less notice, (4) nondisclosure agreements entered into (x) in the ordinary course of business or (y) in connection with discussions, negotiations and transactions related to this Agreement or other potential strategic transactions, or (5) Intercompany Contracts) (each such Contract, and those Contracts that would be required to be listed in Section 2.9(a) of the Disclosure Schedule if not for the fact that they were entered into after the date of this Agreement, together with any exhibits, annexes, appendices or attachments thereto, the “Material Contracts”):

(i)any Contract that requires future payments by or to the Acquired Company in excess of $[***] in any calendar year, including any such Contract

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for the purchase or sale of assets, raw materials, goods, commodities, utilities, equipment, supplies, products or other personal property, or for the provision or receipt of services;

(ii)any Contract related to an acquisition, divestiture, merger or similar transaction;

(iii)(A) any guaranty, surety or performance bond or letter of credit issued or posted, as applicable, by the Acquired Company; (B) any Contract evidencing Debt of the Acquired Company or providing for the creation or granting of any Lien upon any of the property or assets of the Acquired Company (excluding Permitted Encumbrances); (C) any Contract (1) relating to any outstanding loan or advance to any Person (other than advances to consultants in the ordinary course of business consistent with past practice) or (2) obligating or committing the Acquired Company to make any such loans or advances; and (D) any currency, commodity or other hedging, futures, forward, warrant, option, swap or other derivative contract;

(iv)any Contract creating or purporting to create any partnership, strategic alliance, joint venture or similar arrangement, or any sharing of profits or losses, by the Acquired Company with any third party;

(v)any Contract (A) containing covenants restricting or purporting to restrict competition which, in either case, have, would have or purport to have the effect of prohibiting the Acquired Company or, after the Closing, Buyer or the Acquired Company from engaging in any business or activity in any geographic area or other jurisdiction; (B) in which the Acquired Company has granted “exclusivity” obligations or that requires the Acquired Company to deal exclusively with, or grant exclusive rights or rights of first refusal (or rights of first offer) to, any customer, vendor, supplier, distributor, contractor or other Person; (C) that includes minimum purchase conditions (including any take-or-pay Contracts) or other requirements imposed on the Acquired Company, in either case that exceed $[***] in any calendar year; or (D) containing a “most-favored-nation”, “best pricing” or other similar term or provision by which another party to such Contract or any other Person is, or could become, entitled to any benefit, right or privilege which, under the terms of such Contract, must be at least as favorable to such party as those offered to another Person;

(vi)any Contract involving commitments to make capital expenditures or to purchase or sell assets involving $[***] or more individually;

(vii)any lease, sublease, rental or occupancy agreement, license, installment, and conditional sale agreement or agreement under which Acquired Company is lessee or lessor of, or owns, uses or operates any leasehold or other interest in any real or personal property;

(viii)any Contract required to be listed under Section 2.7(e) (Intellectual Property); and

(ix)any Contract with a Governmental Body.

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(b) With respect to each Material Contract: (i) such Material Contract is, to Seller’s Knowledge, with respect to each party thereto other than the Acquired Company, binding and enforceable against such party in accordance with its terms, subject to (A) Laws of general application relating to bankruptcy, insolvency and the relief of debtors, and (B) rules of Law governing specific performance, injunctive relief and other equitable remedies; and (ii) the Acquired Company is not in material breach or material default of such Material Contract and, to Seller’s Knowledge, no other party to such Material Contract is in material breach or material default of such Material Contract. Seller has delivered or otherwise made available to Buyer or its counsel a true and complete copy of each such Material Contract.

2.10Liabilities. Except as set forth in Section 2.10 of the Disclosure Schedule, the Acquired Company has no material liabilities of any kind, whether accrued, contingent, absolute, determined, determinable or otherwise, and there is no existing condition, situation or set of circumstances which would reasonably be expected to result in such a liability, other than liabilities: (i) which are adequately reflected or reserved against in the Unaudited Balance Sheet as of the Balance Sheet Date; (ii) which have been incurred in the ordinary course of business since the Balance Sheet Date (it being understood that any liability arising as a result of breach of Contract or any tortious conduct, or violation of applicable Law, will be deemed not to have been incurred in the ordinary course of business); and (iii) liabilities and obligations incurred in connection with this Agreement.

2.11Compliance with Laws; Permits.

(a)The Acquired Company is in material compliance with, and has been in material compliance with, applicable Laws, and the Acquired Company has not received any written notices of any violation with respect to such Laws, except for violations that are immaterial, have been cured or are no longer being asserted.

(b)Section 2.11(b) of the Disclosure Schedule sets forth a true and complete list of all material permits, licenses, franchises, approvals, certificates, registrations or other authorizations of any Governmental Body that are issued to the Acquired Company and necessary under all applicable Laws for the Acquired Company to carry on its business as currently conducted, together with the name of the Governmental Body issuing such permit (the “Permits”). Except where a failure would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect, the Acquired Company holds all such Permits, is in compliance in all material respects with all such Permits, each such Permit is valid, is in full force and effect and no such Permit has been terminated. None of the Permits will be violated, revoked, terminated or become terminable, in whole or in part, as a result of the transactions contemplated by this Agreement. The Acquired Company has paid all fees, assessments and contributions with respect to the Permits. The Acquired Company has not received any written notice alleging the failure to hold any Permit required to be held by the Acquired Company to conduct its business as conducted immediately prior to the Closing or own its assets.

2.12Certain Business Practices. The Acquired Company, and to Seller’s Knowledge, its representatives (acting on behalf of the Acquired Company), in each case, to the

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extent such action or inaction constitutes a material violation of applicable Anti-Corruption Laws, has not (a) used and is not using any funds for any unlawful contributions, unlawful gifts, unlawful entertainment or other unlawful expenses; (b) made any direct or indirect unlawful payments to any foreign or domestic Government Official; (c) violated and is not violating any Anti-Corruption Laws; (d) established or maintained, and is not maintaining, any unlawful or unrecorded fund of monies or other properties; (e) made, and is not making, any false or fictitious entries on its accounting books and records; (f) made, and is not making, any bribe, payoff, influence payment, kickback or other unlawful payment of any nature, and has not paid, and is not paying, any fee, commission or other payment that has not been properly recorded on its accounting books and records as required by the Anti-Corruption Laws; and (g) otherwise given or received anything of value to or from a Government Official, an intermediary for payment to any individual including Government Officials, any political party or customer, for the purpose of obtaining or retaining business.

2.13Tax Matters.

Except as set forth in Section 2.13 of the Disclosure Schedule:

(a)The Acquired Company has filed all income and other material Acquired Company Returns that it was required to file under applicable Laws (taking into account any valid extensions of the due date for filing). All such Acquired Company Returns were correct and complete in all material respects, when filed. All income and other material Taxes due and owing by the Acquired Company (whether or not shown on any Acquired Company Return) have been paid. There are no Liens for Taxes (other than Permitted Encumbrances) upon any of the assets of the Acquired Company. No extension of time with respect to any date on which an Acquired Company Return was required to be filed by Acquired Company that extends such date beyond the date of this Agreement is in force, and no waiver or agreement by Acquired Company is in force for the extension of time for the payment, collection or assessment of any Taxes beyond the date of this Agreement, in each case, other than pursuant to customary extensions of the due date for filing a Tax Return.

(b)The Acquired Company has kept and maintained, in all material respects, complete and accurate records, invoices and other documents required for Tax purposes, including any claims or elections made to calculate the Tax liability or relief which would arise on any disposal or on the realization of any asset owned by the Acquired Company at Closing.

(c)The Acquired Company has not received written notice from any Governmental Body of any audit or other examination of any Acquired Company Return that has not been resolved in full. Neither Seller, nor the Acquired Company, has received notice, in writing, from any Tax authority that any adjustment relating to any Acquired Company Return has been proposed by any Tax authority. There are no matters relating to Taxes under discussion between any Tax authority and the Acquired Company.

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(d)The Acquired Company has not received written notice from any Governmental Body of any material Tax deficiency that is outstanding, assessed or proposed against Acquired Company and has not been resolved in full. The Acquired Company has never received a written claim from any Governmental Body in a jurisdiction in which the Acquired Company does not file an Acquired Company Returns that the Acquired Company is or may be subject to taxation by that jurisdiction.

(e)The amount of any liability to Tax of the Acquired Company has not, to any material extent, depended on any arrangement or concession (in either case whether formal or informal) with any Tax authority.

(f)The Acquired Company is not a party to any agreement with any third party relating to allocating or sharing the payment of, or liability for, Taxes (other than this Agreement and any contract, such as a loan or a lease, entered into in the ordinary course of business the primary purpose of which is unrelated to Taxes).

(g)The Shares do not derive, directly or indirectly, their value or the greater part of their value from the assets specified in paragraphs (a) to (c) of Section 980(2) of the TCA and the Shares are not shares to which paragraph (e) of the said Section 980(2) of the TCA applies.

(h)Notwithstanding anything herein to the contrary, Seller makes no representation or warranty with respect to Buyer’s or the Acquired Company’s ability to utilize or otherwise benefit from, any particular Tax attribute of the Acquired Company, including without limitation, the Tax basis of assets, net operating losses, capital losses, deductions, Tax credits and other similar items of the Acquired Company.

(i)Neither Seller nor the Acquired Company has made any requests for rulings or determinations, with respect to any Tax of the Acquired Company, that are currently pending before a taxing authority or that have been received and would be binding upon the Acquired Company after the Closing Date.

(j)The Acquired Company is not and has not been during any taxable period for which the period of assessment or collection remains open a member of any affiliated, consolidated, combined, unitary or similar group (other than any such group the common parent of which is Parent).

(k)All deductions or withholdings in respect of (or on account of) any Tax which the Acquired Company has been required to make have been made by the Acquired Company from any payments made by it and have been duly and properly accounted for to the relevant Tax authority.

(l)All material expenses and charges incurred by the Acquired Company prior to the date of this Agreement are fully deductible for Tax purposes and no circumstances exist which would lead to the denial of a Tax deduction by a Tax authority for any such expenses incurred prior to the date of this Agreement.

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(m)The Acquired Company has not claimed a Tax deduction for interest as a charge.

(n)All documents to which the Acquired Company is a party and under which the Acquired Company has any rights or in respect of which the Acquired Company is an accountable person or which form part of the Acquired Company’s title to any asset owned by it have been duly stamped with the correct amount of stamp duty, paid within the applicable time limits. The Acquired Company has not been a party to any transaction involving a claim to or filing with a Tax authority for an exemption from stamp duty.

(o)The Acquired Company has not made a mandatory disclosure to a Tax authority in respect of a transaction or a proposed transaction which enables any person to obtain a Tax advantage and no circumstances exist which mean that the Acquired Company should have made such a disclosure but failed to do so.

(p)The Acquired Company has not been and will not be required, based on the circumstances of the Acquired Company as of Closing and events occurring prior to Closing, to provide information on reportable cross-border arrangements to a Tax authority pursuant to Council Directive 2011/16/EU (as amended by Council Directives 2018/822/EU and 2020/876/EU, and including any implementing legislation or regulation thereto) (“DAC6”) nor has the Acquired Company entered into any reportable cross-border arrangements which will require another person to provide information to a Tax authority pursuant to DAC6.

(q)The Acquired Company is registered for VAT in Ireland and is not and never has been registered for VAT in any jurisdiction other than Ireland.

(r)The Acquired Company has not been required by any Tax authority to give security (or further security) as a condition of supplying goods or services pursuant to or under VAT law.

(s)The Acquired Company has not acted as an agent of any person not established in Ireland in the supply of goods in Ireland nor has allowed such supplies to be made on land owned, occupied or controlled by the Acquired Company.

(t)The Acquired Company is not authorized by any Tax authority to receive supplies of qualifying goods and services at the zero rate of VAT as a result of the Acquired Company primarily being engaged in making zero-rated supplies of goods and / or services.

(u)The Acquired Company has not made any self-supplies of goods or services for VAT purposes at any time within the past five years.

(v)The Acquired Company has not made any supply for VAT purposes to a person connected by financial or legal ties for less than the open market value.

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(w)The Acquired Company has not made any gifts of goods in the course or furtherance of its business. The Acquired Company has not made any supply which is exempt from VAT. The Acquired Company is not a capital goods owner for Irish VAT purposes.

(x)The Acquired Company has not claimed or surrendered group relief, and the Acquired Company has not received payment in respect of any surrender of group relief which may be due to be repaid to any company.

(y)Except as provided in the Unaudited Balance Sheet, the Acquired Company is not obliged to make or entitled to receive any payment for the surrender of group relief in respect of any period ending on or before the Balance Sheet Date.

(z)The Acquired Company has not acquired from any other company any asset (other than assets in respect of which the consideration received on disposal by the transferor would be treated as income for tax purposes) in circumstances where the companies were, at the time of the acquisition, members of the same group of companies for Tax purposes.

(aa)The Acquired Company is not a close company for Tax purposes.

(ab)The Acquired Company has not received any notice under Section 811(6) or assessment under Section 811C of the TCA or engaged in, or been a party to, a tax avoidance transaction within the meaning of Section 811(2) or Section 811C(2) of the TCA or any other transaction or series of transactions or scheme or arrangement of which the main purpose, or one of the main purposes, was or could be said to be the avoidance or deferral of, or a reduction in the liability to, Tax.

(ac)During the three years before the date of this Agreement there has been no major change in the nature or conduct of a trade or business carried on by the Acquired Company and the scale of activities of any trade or business carried on by the Acquired Company has not been small or negligible.

(ad)All expenditure which the Acquired Company has incurred or may incur under any subsisting commitment on research and development (including expenditure on buildings or structures used for research and development) which has qualified for a research and development tax credit is disclosed in the most recent corporation tax computations.

(ae)The entry into or completion of the Transaction Documents, or any of them, will not result in any profit or gain being deemed to accrue to the Acquired Company for Tax purposes pursuant to Section 623 of the TCA. Seller is not otherwise responsible for any Taxes arising from a change to the Tax status of the Acquired Company as a result of the entry into or completion of the Transaction Documents.

(af)This Section 2.13 (Tax Matters) contains the sole and exclusive representations and warranties of Seller with respect to Taxes and any claim for breach of representation with respect to Taxes shall be based on the representations made in this

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Section 2.13 (Tax Matters) and shall not be based on the representations set forth in any other provision of this Agreement. No representation or warranty contained in this Section 2.13 (Tax Matters) (other than subsections (f) and (g)) of this Section 2.13 (Tax Matters) shall be deemed to apply directly or indirectly with respect to any taxable period beginning after Closing or portion of any Straddle Period after Closing. Neither Seller nor the Acquired Company makes any representation as to (i) the amount of, or limitations on, any net operating losses, Tax credits, Tax basis or other Tax attributes of the Acquired Company for purposes of the utilization of such Tax attributes after Closing or (ii) whether the entry into or completion of the Transaction Documents would affect the Tax status of the Acquired Companies.

2.14Employee Benefit Plans and Employee Matters. The Acquired Company does not have, and has not had, any employees or any consultants, agency workers or other individuals providing services to the Acquired Company that could reasonably be deemed to be an employee of the Acquired Company. Except as set forth in Section 2.14 of the Disclosure Schedule, the Acquired Company does not maintain or contribute to, is not a party to, or has any direct or indirect liability with respect to, any Employee Benefit Plan. Except as set forth in Section 2.14 of the Disclosure Schedule, no individual independent contractors or consultants, or any other individuals who could be considered to be an employee of the Acquired Company or would otherwise be protected under applicable Law, including United States or Irish employment legislation, is or has been eligible to participate in any Employee Benefit Plans of the Acquired Company. The Acquired Company is in compliance in all material respects with all applicable Laws relating to classification of individuals as non-employee contractors or consultants.

2.15Insurance. The Acquired Company or its Affiliates in the Parent Group has the insurance of the types and in the amounts set forth in Section 2.15 of the Disclosure Schedule (the “Insurance Policies”) for the benefit of the Acquired Company. True and complete copies of certificates of insurance representing the Insurance Policies have been provided to Buyer prior to the date hereof. The Insurance Policies are in full force and effect and all premiums due and payable under such Insurance Policies have been paid on a timely basis. As of the date of this Agreement and with respect to the Insurance Policies as applied to the Acquired Company, there is no material claim pending under the Insurance Policies as to which coverage has been questioned, denied or disputed (or in respect of which any rights have been reserved) by the underwriters of such policies. To Seller’s Knowledge, as of the date of this Agreement, there is no threatened termination of, or material premium increase with respect to, and no event or circumstance has occurred that, with notice or lapse of time or both, would permit any termination or modification of any of such policies.

2.16Legal Proceedings; Orders. There is no pending Legal Proceeding and, to Seller’s Knowledge, no Person has threatened to commence any Legal Proceeding: (a) against the Acquired Company or any of the assets owned or used by the Acquired Company or any Person whose liability the Acquired Company has retained or assumed, either contractually or by operation of law; or (b) as of the date of this Agreement, that challenges, or that may have the effect of preventing, delaying, making illegal or otherwise interfering with, the Sale or any of the other transactions contemplated by this Agreement. There is no order, writ, injunction, judgment or decree to which the Acquired Company, any of its officers or any of the assets owned or used

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by the Acquired Company is subject. No application has been made for the appointment of an inspector to investigate the affairs of the Company pursuant to the Irish Companies Act.

2.17Authority; Binding Nature of Agreement. Seller has all necessary corporate power and authority to enter into and to perform its obligations under this Agreement. This Agreement constitutes a legal, valid and binding obligation of Seller, enforceable against Seller in accordance with its terms, subject to (i) Laws of general application relating to bankruptcy, insolvency and the relief of debtors, and (ii) rules of law governing specific performance, injunctive relief and other equitable remedies.

2.18Non-Contravention; Governmental Consents. The execution, performance and delivery of this Agreement and the consummation of the transactions contemplated by this Agreement by Seller will not cause a: (a) violation of any of the provisions of the constitution or organizational documents of Seller or the Acquired Company; (b) violation by Seller or the Acquired Company of any Law applicable to Seller and the Acquired Company; or (c) default (or an event that, with or without notice or lapse of time or both would constitute a default) on the part of the Acquired Company under, or give to others any rights of termination, acceleration or cancellation of, or result in the creation of a Lien on any of the properties or assets of the Acquired Company (other than a Permitted Encumbrance) pursuant to, any Material Contract, except with respect to clauses (b) and (c) only, for violations and defaults that would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect or would not reasonably be expected to prevent or materially impair or materially delay the ability of Seller to consummate the transactions contemplated hereby. Except as may be required by any Antitrust Laws or governmental regulation, neither Seller nor the Acquired Company is required to obtain any consent, approval or waiver from any Governmental Body in connection with the execution and delivery of this Agreement or the consummation of the Sale and the other transactions contemplated hereby.

2.19Financial Advisor. No broker, finder or investment banker is entitled to any brokerage or finder’s fee in connection with the Sale or any of the other transactions contemplated by this Agreement based upon arrangements made by or on behalf of the Acquired Company.

2.20Intercompany Contracts. Section 2.20 of the Disclosure Schedule sets forth the Intercompany Contracts in effect as of the date of this Agreement. True and correct copies all such Intercompany Contracts have been made available to Buyer or its representatives on or prior to the date of this Agreement. Other than such Intercompany Contracts, (a) there are no material obligations of the Acquired Company to Seller or any Affiliate of Seller (other than the Acquired Company) and (b) neither Seller nor any of its Affiliates (other than the Acquired Company) has, and to Seller’s Knowledge, no officer or director of Seller or any of its Affiliates (other than the Acquired Company) has any interest in any Contract to which the Acquired Company is party.

2.21Solvency.

(a)No order has been made or petition presented or resolution passed or proceedings taken or, to Seller’s Knowledge, ground arisen for the winding up of either

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Seller or the Acquired Company or for or with a view to appointing an examiner, receiver, administrator, trustee or other similar officer to either Seller or the Acquired Company nor has any distress, execution, sequestration, attachment or other process been levied or entered upon or sued out in respect of either Seller or the Acquired Company or against any property or asset of either Seller or the Acquired Company nor, to Seller’s Knowledge, is any of the foregoing in the process of being so levied, entered upon or sued out, nor is there any unfulfilled or unsatisfied judgment, court order or award outstanding against either Seller or the Acquired Company.

(b)Neither Seller nor the Acquired Company has ceased payment of any debt nor is Seller or the Acquired Company insolvent or unable to pay its debts within the meaning of section 509 or 570 of the Irish Companies Act. No notice has been served on either Seller or the Acquired Company under section 570 of the Irish Companies Act and no arrangement has been or is about to be entered into by either Seller or the Acquired Company under section 453 or section 676 of the Irish Companies Act and no encumbrancer has taken possession or attempted to take possession of or exercised or attempted to exercise any power of sale in respect of the whole or any part of the undertaking, property, assets or revenues of either Seller or the Acquired Company and, to Seller’s Knowledge, there exist no circumstances under which a receiver may be appointed by any person over the whole or any part of the undertaking, property, assets or revenues of either Seller or the Acquired Company and there is no unfulfilled or unsatisfied judgment, ruling, order, award, decree or directive outstanding against Seller or the Acquired Company and there has been no material delay by either Seller or the Acquired Company in the payment of any obligation due for payment.

2.22Powers of Attorney and Agency. There are in force no powers of attorney or other rights of representation given by the Acquired Company and no person, as agent or otherwise, is entitled or authorised to bind or commit the Acquired Company to any obligation not in the ordinary and usual course of its business as conducted immediately prior to the Closing.

2.23Directors. No director of Seller or the Acquired Company is subject to a restriction order pursuant to section 819 of the Irish Companies Act or a disqualification order pursuant to Part 14 Chapter 4 of the Irish Companies Act or any similar or equivalent restriction or disqualification order in any other jurisdiction. The number of directorships of private companies held by any director of the Acquired Company does not and has not since February 21, 2000 exceeded 25 (where directorships of a company and one or more of its subsidiaries count as one directorship).

SECTION 3.Representations and Warranties of Buyer

Novo and NNRE jointly and severally represent and warrant to Seller as follows:

3.1Due Incorporation; Subsidiaries. Novo is a public limited company (an aktieselskab) duly incorporated, validly existing and in good standing under the laws of Denmark. NNRE is a private limited company (an aktieselskab) duly incorporated, validly existing and in good standing under the laws of Denmark.

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3.2Authority; Binding Nature of Agreement. Each of Novo and NNRE has all necessary corporate power and authority to enter into and perform their obligations under this Agreement. The execution, delivery and performance by each of Novo and NNRE of this Agreement have been duly authorized by all necessary action on the part of Novo and NNRE and their respective governing bodies. This Agreement constitutes the legal, valid and binding obligation of Novo and NNRE, enforceable against them in accordance with its terms, subject to (a) Laws of general application relating to bankruptcy, insolvency and the relief of debtors and (b) rules of law governing specific performance, injunctive relief and other equitable remedies.

3.3Non-Contravention; Consents. The execution and delivery of this Agreement and the consummation of the transactions contemplated by this Agreement by Buyer will not: (a) cause a violation of any of the provisions of the respective organizational documents of Buyer (b) cause a violation by Buyer of any Law applicable to Buyer or (c) cause a default on the part of Buyer under any material Contract of Buyer, except, with respect to clauses (b) and (c) only, for violations and defaults that would not reasonably be expected to materially and adversely impact Buyer’s ability to consummate the transactions contemplated by this Agreement. Except as may be required by any Antitrust Laws or governmental regulation, Buyer is not required to obtain any consent, approval or waiver from any Governmental Body or party to a material Contract of Buyer at any time prior to the Closing in connection with the execution and delivery of this Agreement or the consummation of the Sale.

3.4Litigation. As of the date of this Agreement, there is no Legal Proceeding pending (or, to the knowledge of Buyer, being threatened) against Buyer that would delay, restrain, prevent, enjoin or otherwise prohibit the consummation of the Sale.

3.5No Buyer Vote Required. No vote or other action of the stockholders of Buyer is required by applicable Law, the certificate of incorporation or bylaws (or similar charter or organizational documents) of Buyer or otherwise in order for Buyer to consummate the Sale and the transactions contemplated hereby.

1.6Availability of Funds. Buyer has, as of the date of this Agreement, and will have, from and after the Closing, sufficient funds on hand and available through existing liquidity facilities (without restrictions on drawdown that would delay payment of the Purchase Price to consummate the transactions contemplated hereby) to (a) pay the Purchase Price, (b) pay any and all fees and expenses in connection with the transactions contemplated hereby and any debt or equity financing of Buyer, (c) repay or refinance all Debt of the Acquired Company to the extent such repayment or refinancing is required in connection with the transactions contemplated hereby and (d) satisfy all of its other payment obligations payable hereunder and under any agreement ancillary hereto, including Milestone Payments in accordance with Section 1.7 (Contingent Consideration).

SECTION 4.Certain Covenants of Seller

4.1Access.

(a)During the period from the date of this Agreement through the earlier of the Closing or the termination of this Agreement pursuant to Section 9.1 (Termination) (the “Pre-Closing Period”), and upon reasonable advance notice to Seller, Seller shall

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provide Buyer and Buyer’s representatives with reasonable access during normal business hours to the Acquired Company’s facilities and existing books and records and appropriate personnel designated by Seller for the purpose of enabling Buyer to verify the accuracy of Seller’s representations and warranties set forth in Section 2 (Representations and Warranties of Seller); provided, however, that any such access shall be conducted at Buyer’s expense, under the supervision of appropriate personnel designated by Seller and in such a manner as to maintain the confidentiality of this Agreement and the transactions contemplated hereby in accordance with the terms hereof and not to interfere with the normal operation of the business of Seller or the Acquired Company or to create a material risk of damage or destruction to any material assets or property of Seller or the Acquired Company. Any investigation shall be subject to Seller’s and the Acquired Company’s reasonable security measures and insurance requirements and shall not include the right to perform invasive testing. Nothing herein shall require Seller or the Acquired Company to disclose any information to Buyer if such disclosure would, in Seller’s reasonable discretion (a) jeopardize any attorney-client or other legal privilege or (b) contravene any applicable Law or binding agreement entered into prior to the date of this Agreement (including any confidentiality agreement to which Seller or the Acquired Company is a party). The terms and conditions of the Confidentiality Agreement shall apply to any information obtained by Buyer or its representatives in connection with their investigation conducted hereunder.

(b)For [***] after the Closing, Seller shall hold, and shall use commercially reasonable efforts to cause its Affiliates and their respective officers, directors, employees, accountants, counsel, consultants, advisors and agents to hold, in confidence all confidential documents and information concerning the Acquired Company and the Business; provided, however, that such documents and information are not considered confidential if they: (i) are or become generally available to the public through no fault of Seller or its Affiliates; or (ii) are later lawfully acquired by Seller or its Affiliates from sources other than those related to its prior ownership of the Acquired Company.

(c)Notwithstanding Section 4.1(b), Seller or its Affiliates may disclose confidential documents or confidential information concerning the Acquired Company and the Business: (i) to authorized representatives and employees of Seller or its Affiliates and as otherwise is necessary in the course of performing Seller’s obligations hereunder or under any other agreement between Seller, Buyer or the Acquired Company, including, without limitation, the Transition Services Agreement; (ii) for purposes of including applicable information in Parent Group’s financial statements or periodic reports to the extent required by applicable Law, applicable requirements of Nasdaq or applicable accounting standards; (iii) as is required to be disclosed by applicable Law or order of any Governmental Body, or by subpoena, summons or other legal process; provided that Seller shall provide prior notice to Buyer, to the extent legally permissible, of such requirements so that Buyer may seek a protective order or other remedy; or (iv) to prepare and file any Tax Returns, to respond to any inquiries regarding the same from any Governmental Body or to prosecute or defend any action, proceeding or audit by any Governmental Body with respect to such Tax Returns.

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4.2Conduct of the Business of the Acquired Company. During the Pre-Closing Period, except (1) as set forth in Section 4.2 of the Disclosure Schedule, (2) to the extent necessary to comply with Seller’s obligations under this Agreement or any agreement ancillary hereto or necessary to effectuate the transactions contemplated hereby and thereby, (3) as necessary to ensure that Seller or the Acquired Company complies with applicable Laws and contractual obligations or as reasonably necessary to comply with or implement COVID-19 Measures, (4) with Buyer’s written consent (which shall not be unreasonably withheld, conditioned or delayed) or (5) to the extent to be reflected in the Closing Date Transaction Expenses: (i) Seller shall use commercially reasonable efforts to (A) carry on the Acquired Company’s business in the ordinary course, (B) preserve intact the Acquired Company’s present business organization, and (C) preserve the Acquired Company’s relationships with material suppliers, distributors, licensors, licensees and others to whom the Acquired Company has contractual obligations; and (ii) Seller shall cause the Acquired Company not to:

(a)amend the constitution of the Acquired Company;

(b)split, combine or reclassify the Acquired Company’s share capital or issue or authorize the issuance of any other securities in respect of, in lieu of or in substitution for shares of the Acquired Company;

(c)issue any shares of the Acquired Company or securities convertible into, or subscriptions, rights, warrants or options to acquire, or other agreements or commitments of any character obligating it to issue any such shares or other convertible securities;

(d)enter into or adopt any plan or agreement of complete or partial liquidation or dissolution, or file a voluntary petition in bankruptcy or commence a voluntary legal procedure for reorganization, arrangement, adjustment, release or composition of indebtedness in bankruptcy or other similar Laws now or hereafter in effect;

(e)make any capital expenditures, capital additions or capital improvements (other than in accordance with the annual budget for capital expenditures made available to Buyer on or prior to the date of this Agreement);

(f)(i) materially reduce the amount of any insurance coverage provided by existing Insurance Policies other than upon the expiration of any such policy or (ii) fail to maintain in full force and effect insurance coverage materially consistent with past practices;

(g)acquire or agree to acquire by merging with, or by purchasing a portion of the stock or assets of, or by any other manner, any business or any Entity, other than as permitted in clause (e) above or supplies and equipment in the ordinary course of business of the Acquired Company consistent with past practice;

(h)make any loans, advances or capital contributions to, or investments in, any other Person;

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(i)create, incur, assume, suffer to exist or otherwise become liable with respect to any Debt;

(j)enter into or materially amend any Material Contract;

(k)make or change or revoke any material election in respect of Taxes, change any accounting method in respect of Taxes, file any material amended Tax Return, obtain any Tax ruling or enter into any closing or similar agreement, settle any claim or assessment in respect of material Taxes, or consent to any extension or waiver of the limitation period applicable to any claim or assessment in respect of material Taxes other than pursuant to customary extensions of the due date for filing a Tax Return;

(l)make any material changes in its methods of accounting or accounting practices (including with respect to reserves), other than as required by IFRS;

(m)waive, release, assign, compromise, commence, settle or agree to settle any Legal Proceeding, other than waivers, releases, compromises or settlements in the ordinary course of business consistent with past practice that (i) involve only the payment of monetary damages not in excess of $[***] in the aggregate and (ii) do not include the imposition of equitable relief on, or the admission of wrongdoing by, the Acquired Company;

(n)waive, release, fail to enforce or assign any material claims, rights or benefits;

(o)sell, lease, license or otherwise transfer or dispose of, abandon or permit to lapse, fail to take any action necessary to maintain, enforce or protect, or create or incur any Lien (other than Permitted Encumbrances) on, any Company Intellectual Property or Company Licensed Intellectual Property;

(p)(i) adopt, enter into or become a party to any Employee Benefit Plan, (ii) hire or engage any employee or any other individuals who could be considered to be an employee of the Acquired Company or would otherwise be protected under applicable Law as an employee of the Acquired Company or (iii) engage any new individual independent contractor or consultant; or

(q)agree or commit to take any of the actions described in clauses (a) through (m) of this Section 4.2 (Conduct of the Business of the Acquired Company).

Notwithstanding anything to the contrary in this Agreement, nothing contained herein shall give to Buyer, directly or indirectly, the right to control or direct the operations of Seller or the Acquired Company prior to the Closing Date, and prior to the Closing Date, each of Buyer, Seller and the Acquired Company shall exercise, in accordance with the terms and conditions hereof, complete control and supervision of its respective operations.

4.3Exclusivity. Seller agrees that during the Pre-Closing Period, Seller shall not, and shall cause its Affiliates not to, and shall not permit its and their directors, managers,

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officers, employees or representatives to, solicit, encourage or initiate the submission of proposals or offers from, provide any confidential information to, or participate in discussions or negotiations or enter into any agreement (including any letter of intent or memorandum of understanding) with, any Person (other than Buyer and its Affiliates) concerning the sale of any material portion of the business of the Acquired Company or the Shares.

SECTION 5.Additional Covenants of the Parties

5.1Reasonable Best Efforts. Subject to the terms and conditions set forth in this Agreement, each of the parties hereto shall use their respective reasonable best efforts to take, or cause to be taken, all actions, to file, or cause to be filed, all documents and to do, or cause to be done, and to assist and cooperate with the other parties in doing, all things necessary, proper or advisable to consummate and make effective the Sale as soon as reasonably practicable, including (i) the obtaining of all necessary actions or nonactions, waivers, consents, clearances, decisions, declarations, approvals and, expirations or terminations of waiting periods from Governmental Bodies and the making of all necessary registrations and filings and the taking of all steps as may be necessary to obtain any such consent, decision, declaration, approval, clearance or waiver, or expiration or termination of a waiting period by or from, or to avoid an action or proceeding by, any Governmental Body in connection with any Antitrust Laws, (ii) the obtaining of all necessary consents, authorizations, approvals or waivers from third parties and (iii) the execution and delivery of any additional instruments necessary to consummate the Sale; provided, however, no party hereto or any of their respective Affiliates shall be required under any provision of this Agreement to (and, without Buyer’s prior written consent, the Acquired Company shall not) (i) propose, negotiate, commit to or effect, by consent decree, hold separate orders or otherwise, the sale, divesture, disposition, or license of any assets, properties, products, rights, services or businesses of such party, such party’s Subsidiaries, such party’s Affiliates, or the Acquired Company, or any interest therein, or agree to any other structural or conduct remedy, (ii) otherwise take or commit to take any actions that would limit such party, such party’s Subsidiaries’, such party’s Affiliates’, or the Acquired Company’s freedom of action with respect to its or their ability to retain any assets, properties, products, rights, services or businesses of such party, such party’s Subsidiaries, such party’s Affiliates, or the Acquired Company, or any interest or interests therein, or (iii) litigate, challenge or take any action with respect to any action or proceeding by any Person, including any Governmental Body (any of the actions described in this sentence, other than proposing or negotiating (but not committing to or effecting) the actions as set forth in clause (i) of this sentence.

5.2Indemnification of Certain Persons.

(a)All rights to indemnification by the Acquired Company existing in favor of those Persons (the “Indemnified Persons”) for their acts and omissions occurring prior to the Closing, as provided in the Acquired Company’s constitution (as in effect as of the date of this Agreement), shall survive the Sale and shall not be amended, repealed or otherwise modified, and shall be observed by the Acquired Company (and Buyer shall cause the Acquired Company to so observe) to the fullest extent available under applicable Laws, and any claim made requesting indemnification pursuant to such indemnification rights shall continue to be subject to this Section 5.2 (Indemnification of

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Certain Persons) and the indemnification rights provided under this Section 5.2 (Indemnification of Certain Persons) until disposition of such claim.

(b)From the Closing until the [***] anniversary of the date on which the Closing occurs, Buyer shall, and shall cause the Acquired Company (together with its successors and assigns, the “Indemnifying Parties”) to, to the fullest extent permitted under applicable Laws, indemnify, defend and hold harmless each Indemnified Person against all losses, claims, damages, liabilities, fees, expenses, judgments or fines incurred by such Indemnified Person, to the extent arising out of or pertaining to any and all matters pending, existing or occurring at or prior to the Closing, whether asserted or claimed prior to, at or after the Closing, including any such matter arising under any claim with respect to the transactions contemplated herein. Without limiting the foregoing, the Indemnifying Parties shall also, to the fullest extent permitted under applicable Law, advance costs and expenses (including attorneys’ fees) incurred by the Indemnified Persons in connection with matters for which such Indemnified Persons are eligible to be indemnified pursuant to this Section 5.2(b) (Indemnification of Certain Persons) within 15 days after receipt by Buyer of a written request for such advance, subject to the execution by such Indemnified Persons of appropriate undertakings to repay such advanced costs and expenses as required under appropriate circumstances.

(c)In the event that Buyer or the Acquired Company or any of their respective successors or assigns (i) consolidates with or merges into any other Person and shall not be the continuing or surviving corporation or Entity of such consolidation or merger or (ii) transfers all or substantially all of its properties and assets to any Person, then, and in each such case, Buyer shall ensure that the successors and assigns of Buyer or the Acquired Company, as the case may be, shall assume the obligations set forth in this Section 5.2 (Indemnification of Certain Persons).

(d)The provisions of this Section 5.2 (Indemnification of Certain Persons) shall survive the consummation of the Sale and are (i) intended to be for the benefit of, and will be enforceable by, each of the Indemnified Persons and their successors, assigns and heirs and (ii) in addition to, and not in substitution for, any other rights to indemnification or contribution that any such Indemnified Person may have by contract or otherwise. This Section 5.2 (Indemnification of Certain Persons) may not be amended, altered or repealed after the Closing without the prior written consent of the affected Indemnified Person.

5.3Disclosure. Immediately upon the execution of this Agreement, Seller and Buyer shall issue a joint press release in the form attached hereto as Exhibit C (the “Joint Press Release”). During the Pre-Closing Period, other than the Joint Press Release, neither Seller, on the one hand, nor Buyer, on the other hand, shall issue any press release or make any public statement regarding this Agreement or the Sale, or regarding any of the other transactions contemplated by this Agreement, without the prior written consent of the other party; provided, however, that (i) each party hereto may, without such consent, make any public statement in response to questions from investors, customers or vendors, or make internal announcements to employees, so long as such statements are consistent with previous press releases, public disclosures or public statements made jointly by the parties (including the Joint Press Release),

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or individually, if approved by the other party, (ii) either party hereto may issue a press release or public announcement related to this Agreement or the transactions contemplated herein that does not disclose the material terms thereof after the Closing without the consent of the other party and (iii) either party hereto may, without the prior consent of the other party hereto but subject to giving advance notice to the other party, issue any such press release or make any such public announcement or statement as may be required by applicable Laws, including rules and regulations of a national stock exchange.

5.4Tax Matters.

(a)Seller (or its duly authorized agent) shall prepare and file, or shall cause to be prepared and filed, all Acquired Company Returns for any Pre-Closing Tax Period ended on or before the Closing Date and remit any Taxes due in respect of such Seller prepared returns (“Seller Prepared Returns”). All Seller Prepared Returns shall be prepared in a manner consistent with the Acquired Company’s past practices and this Agreement, except as otherwise required by applicable Law. To the extent that any Seller Prepared Return has not been prepared and filed on or before Closing, Seller shall timely provide Buyer with the Seller Prepared Return and funding to pay any Taxes due with respect thereto and Buyer shall cause the return to be authorized and signed by the Acquired Company and submitted to the relevant Governmental Body, in a timely manner, and without amendment.

(b)Buyer (or its duly authorized agent) shall prepare Acquired Company Returns for the Straddle Period (“Buyer Prepared Returns”). Buyer shall cause each such Buyer Prepared Return to be authorized, signed and submitted to the relevant Governmental Body by the Acquired Company within applicable time limits and shall timely remit any Taxes due in respect of such Buyer Prepared Return. Buyer shall prepare each such Buyer Prepared Return in a manner consistent with the past practice of the Acquired Company, and no position shall be taken, election made or method adopted that is inconsistent with positions taken, elections made or methods used by Seller or the Acquired Company in prior periods in filing such Acquired Company Returns to the extent such position, election or method is with respect to a Pre-Closing Tax Period. Buyer will submit each Buyer Prepared Return to Seller for review and comment at least forty-five calendar days prior to the due date for filing such Buyer Prepared Return (or, if such due date is within forty-five calendar days following the Closing Date, as promptly as practicable following the Closing Date). Buyer will reflect, without amendment, any comments provided by Seller in the Buyer Prepared Returns (to the extent that those comments relate to a Pre-Closing Tax Period or any matter that could form the basis for a claim of indemnification pursuant to this Agreement). Seller shall have final determination in relation to any Tax position, election or method adopted or any other matter to be reflected in the Buyer Prepared Return insofar as it relates to a Pre-Closing Tax Period or any matter that could form the basis for a claim of indemnification pursuant to this Agreement. In relation to any Tax position, election or method adopted or any other matter to be reflected in a Buyer Prepared Return insofar as it relates to a Pre-Closing Tax Period, Seller shall, if requested, provide written confirmation to Buyer declaring to the best of its knowledge and belief that the information provided is correct and complete.

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(c)Buyer will not, and will cause the Acquired Company not to (and will not permit their respective Affiliates to) (i) except for the filing of any Seller Prepared Returns in accordance with Section 5.4(a) (Tax Matters) and the preparation and filing of Buyer Prepared Returns prepared and filed in accordance with Section 5.4(b) (Tax Matters), file or amend any Acquired Company Returns with respect to any Pre-Closing Tax Period, (ii) amend any Buyer Prepared Return that was prepared and filed in accordance with Section 5.4(b) (Tax Matters), (iii) make or change any Tax election or change any method of accounting that has retroactive effect to a Pre-Closing Tax Period, (iv) agree to extend or waive the statute of limitations with respect to Taxes of the Acquired Company for a Pre-Closing Tax Period or (v) initiate discussions or examinations with any Governmental Body (including any voluntary disclosures) regarding Taxes with respect to any Pre-Closing Tax Period, except, in each such case, (A) with the prior written consent of Seller (which will not be unreasonably withheld, delayed, or conditioned); provided that, for the avoidance of doubt, it shall not be unreasonable to withhold, delay or condition consent for the purpose of reducing or eliminating Taxes of the Acquired Company in respect of Pre-Closing Tax Periods or Taxes of Seller or its Affiliates or to prevent the taking of any action that could prejudice the Tax position adopted by the Acquired Company for Pre-Closing Tax Periods or of Seller or its Affiliates or (B) if such action could not form the basis for a claim of indemnification pursuant to this Agreement and could not, to the best of Buyer’s knowledge, information and belief acting reasonably, materially increase the Taxes payable by Seller or its Affiliates and could not, to the best of Buyer’s knowledge, information and belief acting reasonably, adversely impact the Tax positions adopted by Seller.

(d)If Buyer becomes aware of any assessment, notice, letter, determination, demand or other document by or on behalf of any taxing authority (whether issued or made before or after the Closing Date and whether satisfied or not at the Closing Date) (each a “Tax Claim”), or any matter that could give rise to a Tax Claim, including any self-assessment return, amended return, computation, accounts or any other documents required to be filed with or submitted to a taxing authority or capable of being submitted to a taxing authority, in any case which relates to a Pre-Closing Tax Period, Buyer shall, in good time and as soon as reasonably practicable, give written notice of that matter to Seller to include written details of all relevant matters relating to the Tax Claim. Any failure to so notify Seller in good time and as soon as reasonably practicable shall relieve Seller of its obligations hereunder with respect to such Tax Claim (including its indemnification obligations under Sections 8.1(c) and (d)), except to the extent such failure shall not have actually prejudiced Seller or its Affiliates. Seller shall have the right to control such Tax Claim, including the defense and settlement thereof; provided that Seller (1) will keep Buyer reasonably informed concerning the progress of such Tax Claim, (2) provide Buyer copies of all correspondence and other documents relevant to such Tax Claim, and (3) will not settle such Tax Claim without the consent of Buyer, which consent will not be unreasonably withheld, conditioned or delayed. Buyer will have the right to participate in the defense of any such Tax Claim (which will include participation in meetings with taxing authorities and/or Governmental Body and review and comment on written submissions to taxing authorities and/or Governmental Body) and to employ counsel, at its own expense, separate from the counsel employed by Seller.

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With respect to any such Tax Claim that Seller does not elect to control pursuant to the prior sentence of this Section 5.4(d) (Tax Matters), Buyer will control such Tax Claim at Seller’s sole cost and expense, including the defense and settlement thereof; provided that if such Tax Claim could reasonably be expected to form the basis for a claim of indemnification pursuant to this Agreement or could increase the Taxes payable by Seller, Buyer (1) will keep Seller reasonably informed concerning the progress of such Tax Claim, (2) provide Seller copies of all correspondence and other documents relevant to such Tax Claim, and (3) will not settle such Tax Claim without the consent of Seller. In addition, if such Tax Claim could reasonably be expected to form the basis for a claim of indemnification pursuant to this Agreement or could increase the Taxes payable by Seller, Seller will have the right to participate in the defense of such Tax Claim (which will include participation in meetings with taxing authorities and review and comment on written submissions to taxing authorities) and to employ counsel, at Seller’s expense, separate from the counsel employed by Buyer.

(e)Buyer shall (and shall cause the Acquired Company and their Affiliates to), on the one hand, and Seller shall, on the other hand, cooperate as and to the extent reasonably requested by the other party, in connection with the preparation and filing of Acquired Company Returns, and any proceeding, investigation, audit or review by a Governmental Body with respect to Taxes. Such cooperation shall include signing any Acquired Company Returns, amended Acquired Company Returns, claims or other documents necessary to settle any Tax controversy, executing powers of attorney, the retention and (upon the other party’s request) the provision of records and information in such party’s control which are reasonably relevant to any such proceeding, investigation, audit or review and making employees available on a mutually convenient basis to provide additional information and explanation of any material provided under this Agreement. Buyer agrees (i) to retain all books and records with respect to Tax matters pertinent to the Acquired Company relating to any taxable period beginning before the Closing Date until the expiration of Seller’s indemnification obligations hereunder with respect to Tax matters, and to abide by all record retention agreements entered into with any taxing authority, and (ii) until the expiration of Seller’s indemnification obligations hereunder with respect to Tax matters, to give Seller reasonable written notice prior to transferring, destroying or discarding any such books and records and, if Seller so requests, Buyer or the Acquired Company, as the case may be, will allow Seller to take possession of such books and records.

(f)Buyer shall be responsible for all Transfer Taxes (as well as the filing of all Tax Returns and any other documentation with respect thereto) in connection with the transactions contemplated hereby.

(g)Both the Acquired Company and Seller form part of a VAT Group within the meaning section 15 of the VATCA (the “Seller VAT Group”), Seller is the relevant company which has filed a form VAT52 pursuant to section 15 of the VATCA and regulation 4 of the VAT Regulations 2010 in respect of the Seller VAT Group (the “VAT Group Remitter”). Seller shall, in its capacity as VAT Group Remitter, procure that on the date hereof, notice is given to the Irish Revenue Commissioners that the Acquired Company will cease to be a member of the Seller VAT Group with effect from the

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Closing Date. Seller shall provide to Buyer a copy of such notice to the Irish Revenue Commissioners together with any correspondence received from or issued to the Irish Revenue Commissioners in relation to this matter as soon as reasonably practicable.

In respect of any VAT period which is prior to or ongoing at the time the Acquired Company ceases to be a member of the Seller VAT Group and in respect of which the filing date for the VAT3 return by the VAT Group Remitter for such period has not passed prior to Closing (“Relevant VAT Periods”), Buyer will procure that the Acquired Company contribute to the VAT Group Remitter that proportion of any VAT for which the VAT Group Remitter is accountable that is properly attributable to supplies, acquisitions and importations in respect of which VAT is due during the Relevant VAT Periods made by the Acquired Company while a member of the Seller VAT Group (“Supplies”) (less any amount of deductible input tax attributable to the Acquired Company during the Relevant VAT Periods while a member of the Seller VAT Group) and that relates to Supplies made or deemed to be made in the Acquired Company’s ordinary course of business up to, and including, the time the Acquired Company ceases to be a member of the Seller VAT Group. Any contribution made under this paragraph shall be made in cleared funds the later of ten Business Days after demand is made for it and ten Business Days before the day on which the VAT Group Remitter must account for that VAT to the Irish Revenue Commissioners. Seller shall procure that an amount equal to any payment made by Buyer under this paragraph shall be promptly and duly accounted for to the Irish Revenue Commissioners. The Acquired Company shall not make a contribution, under this paragraph, to the extent that it relates to an amount for which Seller is liable to Buyer under this Agreement (disregarding any limitations on claims set out herein) or would have been so liable had the Acquired Company never been a member of the Seller VAT Group and had instead been separately registered for VAT.

Seller shall pay, or shall procure to be paid, to the Acquired Company an amount equivalent to the proportion of any repayment of VAT received by the VAT Group Remitter in respect of the Relevant VAT Periods from the Irish Revenue Commissioners or of any credit obtained by reference to an excess of deductible input tax over output tax that is attributable to Supplies made, or deemed to be made, by the Acquired Company while a member of Seller VAT Group in respect of the Relevant VAT Periods (ignoring, for this purpose, the deeming provisions in section 15(1) of VATCA) within ten Business Days of receipt by, or offset against a liability of, the VAT Group Remitter.

(h)For the purposes of preparing all income Tax Returns described in Section 5.4 (Tax Matters) and calculating Pre-Closing Taxes, no election under Section 338 or 336(e) of the Code (or any comparable applicable provision of state, local or non-U.S. Tax Law) shall be made with respect to the Sale.

(i)Prior to or as soon as practicable after the date hereof, Seller shall apply to the Irish taxing authority for a certificate providing that Seller is a resident for the purposes of Tax in Ireland (such certificate, a “Tax Certificate”). Seller shall provide a copy of such Tax Certificate to Buyer as soon as it is available.

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1.5Notification of Certain Events. During the Pre-Closing Period, each party hereto shall promptly notify the other party of, and furnish such other party with any information it may reasonably request with respect to, the occurrence of any event or condition or the existence of any fact that may reasonably be expected to cause, in the case Buyer is such notified party, any of the conditions to the obligations of Buyer to consummate the Sale set forth in Section 6 (Conditions Precedent to Obligations of Buyer) or, in the case Seller is such notified party, any of the conditions to the obligations of Seller to consummate the Sale set forth in Section 7 (Conditions Precedent to Obligations of Seller), not to be satisfied. A party’s satisfaction of its obligations in the foregoing sentence shall not relieve such party of any of its other obligations under this Agreement.

1.6Guaranty of Parent. Parent irrevocably guarantees each and every covenant and obligation of Seller and the full and timely performance of Seller’s obligations under the provisions of this Agreement. This is a guaranty of payment and performance, and not of collection, and Parent acknowledges and agrees that this guaranty is full and unconditional, and no release or extinguishments of Seller’s liabilities, whether by decree in any bankruptcy proceeding or otherwise, will affect the continuing validity and enforceability of this guaranty. Parent hereby waives, for the benefit of each Buyer Indemnified Party, (i) any right to require any Buyer Indemnified Party as a condition of performance of Parent to proceed against Seller or pursue any other remedies whatsoever and (ii) to the fullest extent permitted by applicable Law, any defenses or benefits that may be derived from or afforded by law that limit the liability of or exonerate guarantors or sureties, except to the extent that any such defense is available to Seller. Parent understands that Buyer is relying on this guaranty in entering into this Agreement.

SECTION 6.Conditions Precedent to Obligations of Buyer

The obligations of Buyer to effect the Sale are subject to the satisfaction (or waiver by Buyer), at or prior to the Closing, of each of the following conditions; provided that if the Closing occurs, all Closing conditions set forth in this Section 6 (Conditions Precedent to Obligations of Buyer) that have not been fully satisfied as of the Closing shall be deemed to have been waived by Buyer:

6.1Accuracy of Representations and Warranties. The Specified Representations (other than Section 2.3 (Title to Shares; Capitalization) shall be true and correct in all material respects as of the Closing Date with the same effect as though made on and as of the Closing (except to the extent expressly made as of an earlier date, in which case such representations and warranties shall be so true and correct as of such earlier date). The representations and warranties of Seller set forth in Section 2.3 (Title to Shares; Capitalization) shall be true and correct in all respects, subject only to de minimis exceptions with the same effect as though made on and as of the Closing (except to the extent expressly made as of an earlier date, in which case such representations and warranties shall be so true and correct as of such earlier date, subject only to de minimis exceptions as of such date). The representations and warranties of Seller set forth in clause (a) of Section 2.5 (Absence of Certain Changes) shall be true and correct as of the date hereof. The other representations and warranties of Seller set forth in Section 2 (Representations and Warranties of Seller) shall be true and correct (without giving effect to any limitation as to materiality or Company Material Adverse Effect set forth therein) as of the Closing Date with the same effect as though made on and as of the Closing (except to the extent

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expressly made as of an earlier date, in which case such representations and warranties shall be so true and correct as of such earlier date), except where the failure of such representations and warranties to be so true and correct would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect.

6.2Performance of Covenants. Seller shall have performed and complied with, in all material respects, all of its covenants contained in this Agreement at or before the Closing (to the extent that such covenants require performance by Seller at or before the Closing).

6.3No Restraints. No temporary restraining order, preliminary or permanent injunction or other order preventing the consummation of the Sale by Buyer shall have been issued by any Governmental Body of competent jurisdiction and remain in effect, and no material Law shall have been enacted since the date of this Agreement that makes consummation of the Sale by Buyer illegal.

6.4Agreements and Documents. Buyer shall have received the following agreements and documents, each of which shall be in full force and effect:

(a)a duly completed and dated stock transfer form for the Shares, duly executed by Seller in favor of Buyer and the share certificate(s) representing the Shares, if any (or, in the case of any share certificate(s) found to be missing, an indemnity in a form satisfactory to Buyer, acting reasonably);

(b)details of the Irish tax reference number (within the meaning of Regulation 2 of the Stamp Duty (E-Stamping of Instruments) Regulations 2009 (S.I. no. 476 of 2009)) of Seller;

(c)either a certificate of the kind described in section 980 of the TCA or a letter from the auditors of the Acquired Company addressed to the Acquired Company (in a form reasonably satisfactory to Buyer) confirming that none is required;

(d)written resignations of all directors of the Acquired Company from their directorships in and offices of profit under and employment with the Acquired Company, with such written resignations given as deeds, effective as of the Closing and containing an acknowledgement that each has no claim against the Acquired Company in respect of breach of contract, compensation for loss of office or otherwise howsoever arising;

(e)a written resignation executed as a deed from the secretary of the Acquired Company containing an acknowledgement that he has no claim against the Acquired Company in respect of breach of contract, compensation for loss of office or otherwise howsoever arising;

(f)a written resignation of the existing auditors of the Acquired Company and containing a statement complying with the provisions of section 400(3)(a) of the Irish Companies Act that there are no circumstances connected with their resignation which they consider should be brought to the attention of the members or creditors of the Acquired Company; and

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(g)wire instructions for the payment of the Closing Purchase Price.

6.5Closing Certificate. An authorized officer of Seller shall have delivered to Buyer a certificate to the effect that each of the conditions specified above in Sections 6.1 (Accuracy of Representations and Warranties) and 6.2 (Performance of Covenants) is satisfied in all respects.

6.6Company Material Adverse Effect. Since the date of this Agreement, there shall not have been a Company Material Adverse Effect that shall have been continuing.

6.7Intercompany Contracts. The Intercompany Contracts set forth in Section 6.7 of the Disclosure Schedule shall be terminated, with no further liability or obligation, directly or indirectly, of any kind thereunder on the part of the Acquired Company, effective immediately prior to the Closing.

6.8Transition Services Agreement. The Transition Services Agreement shall have been executed by Seller.

SECTION 7.Conditions Precedent to Obligations of Seller

The obligation of Seller to effect the Sale is subject to the satisfaction (or waiver by Seller), at or prior to the Closing, of the following conditions, provided that if the Closing occurs, all Closing conditions set forth in this Section 7 (Conditions Precedent to Obligations of Seller) that have not been fully satisfied as of the Closing shall be deemed to have been waived by Seller:

7.1Accuracy of Representations and Warranties. The representations and warranties of Buyer set forth in Section 3 (Representations and Warranties of Buyer) shall be true and correct in all material respects as of as of the Closing Date with the same effect as though made on and as of the Closing (except to the extent expressly made as of an earlier date, in which case such representations and warranties shall be so true and correct as of such earlier date).

7.2Performance of Covenants. Buyer shall have performed and complied with, in all material respects, all of its covenants contained in this Agreement at or before the Closing (to the extent that such covenants require performance by Buyer at or before the Closing).

7.3No Restraints. No temporary restraining order, preliminary or permanent injunction or other order preventing the consummation of the Sale by Seller shall have been issued by any Governmental Body of competent jurisdiction and remain in effect, and no material Law shall have been enacted since the date of this Agreement that makes consummation of the Sale by Seller illegal.

7.4Closing Certificate. An authorized officer of Buyer shall have delivered to Seller a certificate to the effect that each of the conditions specified above in Sections 7.1 (Accuracy of Representations and Warranties) and 7.2 (Performance of Covenants) is satisfied in all respects.

7.5Transition Services Agreement. The Transition Services Agreement shall have been executed by Buyer.

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SECTION 8.Indemnification

8.1Indemnification of Buyer. Subject to the other provisions of this Section 8 (Indemnification), from and after the Closing Date, Seller shall indemnify Buyer, its Affiliates (including after the Closing, the Acquired Company) and their respective officers and directors (each, a “Buyer Indemnified Party”) in respect of, and hold the Buyer Indemnified Parties harmless against, any Damages suffered by any Buyer Indemnified Party resulting from:

(a)any inaccuracy in or breach of any representation or warranty set forth in Section 2 (Representations and Warranties of Seller) as of the Closing Date (except for those representations and warranties that address matters only as of an earlier specified date, the accuracy of which shall be determined as of such earlier specified date); provided, however, that all materiality qualifications including “material” and “Company Material Adverse Effect” contained in Section 2 (Representations and Warranties of Seller) shall be disregarded for all purposes under this Section 8.1(a), except for materiality qualifications including “material” and “Company Material Adverse Effect” that appear in Sections [***];

(b)any breach by Seller of any covenant or agreement contained in this Agreement;

(c)all Pre-Closing Taxes;

(d)any Deemed Tax Liability;

(e)any Secondary Tax Liability;

(f)any Closing Date Transaction Expenses or Closing Date Indebtedness in each case to the extent not considered in connection with the purchase price adjustment process; or

(g)any liability of the Acquired Company, whether contingent or noncontingent, arising from the Acquired Company’s (A) ownership, operation or sale of [***] and (B) membership in the Parent Group prior to Closing.

provided, however, that any Adjustment Amount payable pursuant to Section 1.6 (Post Closing Adjustment to Closing Purchase Price) shall be determined in accordance with Section 1.6 (Post Closing Adjustment to Closing Purchase Price) and not this Section 8 (Indemnification).

8.2Indemnification of Seller. Subject to the other provisions of this Section 8 (Indemnification), following the Closing, Buyer shall indemnify Seller, its Affiliates and their respective officers and directors in respect of, and hold them harmless against, any Damages suffered by such Persons resulting from:

(a)any inaccuracy in or breach of any representation or warranty Section 3 (Representations and Warranties of Buyer) as of the Closing Date (except for those representations and warranties that address matters only as of an earlier specified date,

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the accuracy of which shall be determined as of such earlier specified date); provided, however, that all materiality qualifications including “material” and “Company Material Adverse Effect” contained in Section 3 (Representations and Warranties of Buyer) shall be disregarded for all purposes under this Section 8.2(a);

(b)any breach by Buyer of any covenant or agreement contained in this Agreement; or

(c)any Tax liability of (i) Seller, (ii) any Seller Affiliate which was, on or prior to the Closing Date, a member of the same group of companies (within the meaning of section 629A(1) of the TCA) as the Acquired Company or (iii) any Person who was, on or prior to the Closing Date, a controlling director (within the meaning of section 629A(1) of the TCA) of the Acquired Company, where such Tax is a liability imposed pursuant to section 629 of the TCA as a consequence of the Acquired Company ceasing to be resident in Ireland for Tax purposes within a period of [***] of the Closing Date and Buyer or the Acquired Company having failed to discharge that liability to Tax;

8.3Third-Party Claims.

(a)In the event Buyer becomes aware of a third-party claim (including any Legal Proceeding commenced or threatened to be commenced by any third-party) that Buyer reasonably believes may result in an indemnification pursuant to Section 8.1 (Indemnification of Buyer) (any such claim, a “Third-Party Claim”), Buyer shall promptly notify Seller in writing of such Third-Party Claim (such notice, the “Claim Notice”). The Claim Notice shall be accompanied by copies of any documentation submitted by the third party making such Third-Party Claim and shall describe in reasonable detail (to the extent known by Buyer) the facts constituting the basis for such Third-Party Claim and the amount of the claimed Damages. The failure to so notify the Indemnifying Party shall not relieve the Indemnifying Party of its obligations hereunder, except to the extent such failure shall have materially and adversely prejudiced the Indemnifying Party (it being understood that a forfeiture of rights or defenses would materially and adversely prejudice the Indemnifying Party).

(b)Within 20 Business Days after receipt of any Claim Notice, Seller may, upon written notice thereof to Buyer, assume control of the defense of the Third-Party Claim referred to therein at Seller’s sole cost and expense with counsel reasonably satisfactory to Buyer. If such notice is timely given, Seller shall be entitled to control such defense so long as (i) the Third-Party Claim primarily seeks a claim for monetary damages against a Buyer Indemnified Party and (ii) the Third-Party Claim does not relate to or otherwise arise in connection with any criminal or regulatory Legal Proceeding or any Legal Proceeding involving any Intellectual Property (subject to the limitations in Section 8.3(d)).

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(c)If Seller does not so assume control of the defense of such Third-Party Claim, Buyer shall control the defense of such Third-Party Claim. The party not controlling the defense of such Third-Party Claim (the “Non-Controlling Party”) may participate therein at its own expense. The party controlling the defense of such Third-Party Claim (the “Controlling Party”) shall keep the Non-Controlling Party reasonably apprised of the status of such Third-Party Claim and the defense thereof and shall consider in good faith recommendations made by the Non-Controlling Party with respect thereto.

(d)The Non-Controlling Party shall furnish the Controlling Party with such information as it may have with respect to such Third-Party Claim (including copies of any summons, complaint or other pleading which may have been served on such party and any written claim, demand, invoice, billing or other document evidencing or asserting the same) and shall otherwise cooperate with and assist the Controlling Party in the defense of such Third-Party Claim. Neither Buyer nor Seller shall agree to any settlement of, or the entry of any judgment arising from, any such Third-Party Claim without the prior written consent of the other of such parties, which shall not be unreasonably withheld or delayed; provided, however, that the consent of Buyer shall not be required with respect to any such settlement or judgment if (i) Parent agrees in writing to pay the full amount of Damages in connection with such Third-Party Claim (net of any remaining Indemnity Deductible), (ii) does not impose injunctive, equitable or other similar type of relief (including any relief that limits the scope of or otherwise affects any of Buyer’s or any of its Affiliates’ (including the Acquired Company’s) rights relating to any Company Intellectual Property or Company Licensed Intellectual Property) or require an admission of liability or wrongdoing on behalf of the Buyer Indemnified Party or any of its Affiliates and (iii) such settlement or judgment includes a complete release of the Buyer Indemnified Party and its Affiliates from all Damages and obligations with respect to such Third-Party Claim. Any party’s assumption of the defense of any Third-Party Claim can be made with a reservation of the right to contest the right of the Indemnified Party to be indemnified with respect to such claim under this Agreement, and a party’s consent to any settlement of a Third-Party Claim shall not be used as evidence of the truth of the allegations in any Third-Party Claim or the merits of such Third-Party Claim. Furthermore, the existence of any Third-Party Claim shall not create a presumption of any breach by a party to this Agreement of any of its representations, warranties or covenants set forth in this Agreement. The procedures in this Section 8.3 (Third-Party Claims) shall not apply to any Tax Claim, which shall be governed solely by Section 5.4(d) (Tax Matters) or to the determination of any Adjustment Amount, which shall be governed solely by Section 1.6 (Post Closing Adjustment to Closing Purchase Price).

8.4Indemnification Mechanics.

(a)In order to seek indemnification under this Section 8 (Indemnification), the Indemnified Party shall deliver a written demand in good faith (an “Indemnification Demand”) to Seller (if the Indemnified Party is a Buyer Indemnified Party) or Buyer (if the Indemnified Party is Seller, its Affiliates or their respective officers and directors) which contains (i) a description and the amount of any Damages incurred or reasonably

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expected to be incurred by the Indemnified Party, (ii) a statement that the Indemnified Party is entitled to indemnification under Section 8.1 (Indemnification of Buyer) or Section 8.2 (Indemnification of Seller) for such Damages and a reasonable explanation of the basis therefor and (iii) a demand for payment in the amount of such Damages.

(b)Upon reasonable request, the Indemnified Party shall furnish Seller or Buyer, as applicable, with any information to the extent that such information is reasonably necessary in order to evaluate the Indemnification Demand. If Seller or Buyer, as applicable, in good faith objects to any claim made by the Indemnified Party in the Indemnification Demand, then Seller or Buyer, as applicable, shall deliver a written notice (an “Indemnification Dispute Notice”) to the Indemnified Party within 30 days following receipt by Seller or Buyer, as applicable, of an Indemnification Demand from such Indemnified Party. The Indemnification Dispute Notice shall set forth in reasonable detail the principal basis for the dispute of any claim made by the Indemnified Party in the Indemnification Demand. If Seller or Buyer, as applicable, fails to deliver an Indemnification Dispute Notice prior to the expiration of such 30-day period, then the indemnity claim set forth in the Indemnification Demand shall be conclusively determined in the Indemnified Party’s favor for purposes of this Section 8 (Indemnification), and the Indemnified Party shall be indemnified for the amount of the Damages stated in such Indemnification Demand (or, in the case of any notice in which the Damages (or any portion thereof) are estimated, the amount of such Damages (or such portion thereof) as finally determined) on demand or, in the case of any notice in which the Damages (or any portion thereof) are estimated, on such later date when the amount of such Damages (or such portion thereof) becomes finally determined, in either case, subject to the limitations of this Section 8 (Indemnification).

(c)If Seller or Buyer, as applicable, delivers an Indemnification Dispute Notice, then the Indemnified Party and Seller or Buyer, as applicable, shall attempt in good faith to resolve any such objections raised by Seller or Buyer, as applicable, in such Indemnification Dispute Notice. If the Indemnified Party and Seller or Buyer, as applicable, agree to a resolution of such objection, then a memorandum setting forth the matters conclusively determined by the Indemnified Party and Seller or Buyer, as applicable, shall be prepared and signed by both parties, and shall be binding and conclusive upon the parties hereto.

(d)If no such resolution can be reached during the 30-day period following the Indemnified Party’s receipt of a given Indemnification Dispute Notice, then upon the expiration of such 30-day period (or such longer period as may be mutually agreed), the Indemnified Party shall be entitled to pursue all remedies available to them under this Agreement or otherwise under Law or equity with respect to such claims (in each case subject to the terms and limitations set forth in this Agreement, including Section 10.5 (Applicable Law; Jurisdiction)).

8.5Survival. All representations and warranties contained in this Agreement shall (a) survive the Closing and (b) shall, (i) in the case of the representations and warranties set forth in Section 2.13 (Tax Matters), expire at 5:00 p.m. Dublin, Ireland time on the date that is [***] from the end of the accounting period in which the Irish corporation Tax Return relating to the

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accounting period of the Acquired Company current at the Closing Date is due to be filed; except in the case of the representation and warranty set forth in Section 2.13(ee) which shall expire at 5:00 p.m. Dublin, Ireland time on the date that is [***] from the Closing Date, (ii) in the case of the representations and warranties set forth in Section 2.7 (Intellectual Property), expire at 5:00 p.m. Dublin, Ireland time on the date that is [***] from the Closing Date, (iii) in the case of the Specified Representations (other than Section 2.13 (Tax Matters)), expire at 5:00 p.m. Dublin, Ireland time on the date that is [***] from the Closing Date and (iv) in the case of all other representations and warranties, expire at 5:00 p.m. Dublin, Ireland time on the date that is [***] after the Closing Date; provided, however, that with respect to any claim as to which an Indemnified Party shall have, on or prior to such date, delivered an Indemnification Demand, the indemnification obligations hereunder with respect to such claim, and the claim asserted in such Indemnification Demand, shall survive until such time as such claim is fully and finally resolved. All covenants and agreements of the parties contained in this Agreement (A) that are to be performed at or prior to the Closing shall expire at 5:00 p.m. Dublin, Ireland time on the date that is [***] after the Closing Date and (B) that are to be performed following the Closing shall continue in effect and expire in accordance with their respective terms. It is the express intent of the parties that, if an applicable survival period as contemplated by this Section 8.5 (Survival) is shorter than the statute of limitations that would otherwise have been applicable, then, by contract, the applicable statute of limitations shall be reduced to the shortened survival period contemplated hereby. The parties further acknowledge that the time periods set forth in this Section 8.5 (Survival) for the assertion of claims under this Agreement are the result of arms’-length negotiations among the parties and that they intend for the time periods to be enforced as agreed by the parties.

8.6Sole and Exclusive Remedy; Limitations.

(a)From and after the Closing, except (i) for the right to pursue specific performance pursuant to Section 10.15 (Specific Performance), (ii) any claim of common law fraud asserted against the Person who committed such common law fraud (but otherwise subject to the limitations of this Section 8 (Indemnification)) and (iii) pursuant to Section 1.6 (Post Closing Adjustment to Closing Purchase Price) (but otherwise subject to the limitations therein), the indemnification terms set forth in this Section 8 (Indemnification) shall constitute the sole and exclusive remedy of Buyer for any and all Damages or other claims relating to or arising from this Agreement regardless of the legal theory under which such liability or obligation may be sought to be imposed, whether sounding in contract or tort, or whether at Law or in equity, or otherwise, and the parties hereby agree that Buyer shall not have any remedy or recourse with respect to any of the foregoing other than as expressly set forth in this Section 8 (Indemnification) (and subject to the limitations and terms set forth in this Section 8 (Indemnification)). Notwithstanding anything herein to the contrary, in no event shall Seller’s liability to Buyer under this Agreement (other than pursuant to Section 8.1(f) and Section 8.1(g) or for breach of Section 2.2(a)) exceed the Closing Purchase Price and any Milestone Payment actually received by Seller.

(b)Other than for any claim of common law fraud asserted against the Person who committed such common law fraud (but otherwise subject to the limitations of this Section 8 (Indemnification)), from and after the Closing, the Buyer Indemnified Parties

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may not avoid the limitation on liability set forth in this Section 8 (Indemnification) by (i) seeking damages for breach of contract, tort or pursuant to any other theory of liability, all of which are hereby waived, or (ii) asserting or threatening any claim against any Person that is not a party for breaches of the representations, warranties, covenants and agreements contained in this Agreement. The parties hereto agree that the provisions in this Agreement relating to indemnification, and the limits imposed on the remedies with respect to this Agreement and the transactions contemplated hereby, were specifically bargained for between sophisticated parties and were specifically taken into account in the determination of the amounts to be paid to Seller hereunder.

(c)No current or former shareholder, director, officer, employee, Affiliate or advisor of Seller, each of whom shall be an express third-party beneficiary thereof, shall have any liability of any nature to Buyer with respect to the breach by Seller of any representation, warranty, covenant or agreement contained in this Agreement or any other matter relating to the Sale or the other transactions contemplated by this Agreement. The parties acknowledge that (i) no current or former shareholder, director, officer, employee, Affiliate or advisor of Seller has made or is making any representations or warranties whatsoever regarding Seller or the Acquired Company or the subject matter of this Agreement, express or implied, (ii) except as expressly provided in Section 2 (Representations and Warranties of Seller) or as set forth in any other Transaction Document or in any certificate delivered with respect to this Agreement, neither Seller nor the Acquired Company has made or is making, and Buyer is not relying upon, any representations or warranties whatsoever regarding Seller or the Acquired Company or the subject matter of this Agreement, express or implied and (iii) there shall not be any multiple recovery for any Damages.

(d)Subject to Section 8.6(e), the maximum Damages indemnifiable pursuant to Section 8.1(a) shall be an amount equal to $[***] (the “Indemnity Cap”); provided, however, that the Indemnity Cap shall not apply to any Damages related to the inaccuracy in, or breach of, any of the Specified Representations, which Damages (other than any Damages arising from a breach of Section [***]) shall be limited to the Closing Purchase Price and any Milestone Payments actually received by Seller; provided, further, that in the event that any Milestone Payment becomes payable to Seller prior to the payment of any Damages, then the Indemnity Cap shall automatically [***].

(e)Notwithstanding anything in Section 8.6(d), in the event that Damages indemnifiable pursuant to Section 8.1(a) exceed the Indemnity Cap, Buyer shall be entitled to indemnification for Damages solely with respect to an inaccuracy in, or breach of, the representations or warranties set forth in Section [***] in excess of the Indemnity Cap up to an aggregate amount of Damages equal to [***].

(f)Notwithstanding anything to the contrary contained herein, Buyer shall not be entitled to recover any Damages under Section 8.1(a) unless and until the aggregate Damages (excluding Non-Qualified Damages) for which they would otherwise be entitled to indemnification under Section 8.1(a) exceed $[***] (the “Indemnity Deductible”) (at which point Buyer shall become entitled to be indemnified only for such Damages (excluding Non-Qualified Damages) in excess of the Indemnity Deductible).

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Seller shall not indemnify Buyer for, and Buyer shall not be entitled to recover for, in each case, any Damages with respect to indemnification pursuant to Section 8.1(a) which do not exceed $[***] per claim (any such Damages that are disregarded pursuant to this sentence, “Non-Qualified Damages”). Notwithstanding the foregoing, the limitations of this Section 8.6(f) shall not apply to any claim of breach of the Specified Representations.

8.7Mitigation of Losses. After Buyer becomes aware of any event that would reasonably be expected to give rise to any Damages, Buyer shall ensure that all commercially reasonable steps are taken and all commercially reasonable assistance is given to avoid or mitigate such Damages which in the absence of mitigation might give rise to or increase Damages in respect of any claim under this Section 8 (Indemnification). In the event Buyer fails to so mitigate such indemnifiable Damages, Buyer will not be able to recover the portion of such Damages that could reasonably have been avoided had Buyer made such efforts.

8.8Provisions. No indemnification will be available to Buyer in respect of any Damages to the extent the fact, matter, event or circumstance giving rise to the claim or on which it is based is allowed, provided, accrued or reserved for in the Company Financial Statements or is provided for or otherwise taken into account in determining any adjustment pursuant to Section 1.6 (Post Closing Adjustment to Closing Purchase Price).

8.9Change of Law. No indemnification will be available to Buyer in respect of any Damages to the extent that those Damages arise from, or are increased or extended, as a result of a change in Law occurring after the Closing Date, with retroactive effect (a “Change of Law”), other than a Change of Law in respect of Taxes; provided that indemnification shall not be sought in respect of Taxes as a result of a Change of Law until the factual basis for such indemnification arises in the context of a Third-Party Claim or Tax Claim.

8.10Voluntary Acts. No indemnification will be available to Buyer in respect of any claim made pursuant to Section 8.1 (Indemnification of Buyer) in relation to Tax matters to the extent such claim would not have arisen but for a voluntary act, transaction, supply or occurrence (“Voluntary Act”) carried out by Buyer, or a Buyer Affiliate, on or after the Closing Date except for these purposes a Voluntary Act shall not include any act, transaction, supply or occurrence which (i) was carried out pursuant to a legally binding obligation entered into by the Acquired Company prior to the Closing Date, (ii) was carried out with the written consent of Seller or (iii) is undertaken solely with respect to a Tax period other than a Pre-Closing Tax Period and does not affect a Pre-Closing Tax Period (e.g., amending a Tax Return for a Pre-Closing Tax Period or making a Tax election retroactive to a Pre-Closing Tax period each would constitute a Voluntary Act whereas taking the same actions with respect to a Tax period other than a Pre-Closing Tax Period would not constitute a Voluntary Act provided that the taking of any such action with respect to a Tax Period other than a Pre-Closing Tax Period would not address prejudicially any Pre-Closing tax positions taken by the Acquired Company.

8.11Treatment of Payments. The parties hereto agree to treat any payments or offset amounts made pursuant to this Section 8 (Indemnification) as adjustments to the Purchase Price for all purposes, including all Tax purposes to the maximum extent permitted by applicable Law.

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8.12Offset.

(a)Notwithstanding anything in this Agreement to the contrary, the parties acknowledge and agree that, in addition to any other right or remedy under this Agreement, Buyer is expressly authorized to set off against any unpaid future Milestone Payments (i) any Damages for which it is entitled to indemnification under Section 8.1 (Indemnification of Buyer) (subject to the other limitations set forth in this Section 8 (Indemnification)), following final resolution of the claims set forth in any Indemnification Demand pursuant to Section 8.4 (Indemnification Mechanics) and (ii) any Adjustment Amount, if such Adjustment Amount is a negative number after the final determination of such amount pursuant to Section 1.6 (Post Closing Adjustment to Closing Purchase Price).

(b)If and to the extent, at the time any Milestone Payment is due and payable, there shall be (i) any outstanding Indemnification Demand with respect to claims pursuant to Section 8.1 (Indemnification), the amount of Damages with respect to which shall not have been finally determined, or (ii) any unpaid amount of an Adjustment Amount payable to Buyer after the final determination of such amount pursuant to Section 1.6 (Post Closing Adjustment to Closing Purchase Price), then Buyer shall be entitled to withhold from such Milestone Payment the amount of (x) Damages (subject to the limitations set forth herein, including the Indemnity Cap and exclusion of Non-Qualified Damages, and taking into account any Milestone Payment that was previously withheld by Buyer) that Buyer reasonably estimates to be subject to such indemnification claim and that is set forth in the Indemnification Demand or (y) the unpaid Adjustment Amount (taking into account any Adjustment Amount that was previously withheld by Buyer) that was finally determined pursuant to Section 1.6 (Post Closing Adjustment to Closing Purchase Price). If the final amount of Damages for such claim is less than the amount withheld from such Milestone Payment for such claim, then Buyer shall promptly, and in any event within five Business Days following the final determination of the amount of such Damages, deliver the difference to Seller by wire transfer in immediately available funds to an account designated by Seller. If the final amount of Damages for such claim exceeds the amount by which such Milestone Payment was reduced for such claim, then, subject to the limitations set forth in this Section 8 (Indemnification), Buyer shall continue to be entitled to the amount of such excess pursuant to the terms and conditions of this Section 8 (Indemnification).

SECTION 9.Termination

9.1Termination. This Agreement may be terminated prior to the Closing:

(a)by mutual written consent of Buyer and Seller;

(b)by either Buyer or Seller if the Sale shall not have been consummated by the End Date; provided, however, that a party shall not be permitted to terminate this Agreement pursuant to this Section 9.1(b) (Termination) if the failure to consummate the Sale by the End Date is attributable to a failure on the part of such party to perform any

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covenant in this Agreement required to be performed by such party at or prior to the Closing;

(c)by either Buyer or Seller if a Governmental Body of competent jurisdiction shall have issued a final and nonappealable order having the effect of permanently restraining, enjoining or otherwise prohibiting the Sale;

(d)by Buyer, if Seller shall have materially breached or materially failed to perform any of its representations, warranties, covenants or agreements contained in this Agreement, which material breach or failure to perform (i) would give rise to the failure of a condition set forth in Section 6.1 (Accuracy of Representations and Warranties) or Section 6.2 (Performance of Covenants) and (ii) cannot be or has not been cured within 30 days following receipt by Seller of written notice of such material breach or failure to perform; provided, however, that Buyer shall not have the right to terminate this Agreement pursuant to this Section 9.1(d) (Termination) if Buyer is then in material breach of this Agreement; or

(e)by Seller, if Buyer shall have materially breached or materially failed to perform any of their respective representations, warranties, covenants or agreements contained in this Agreement, which material breach or failure to perform (i) would give rise to the failure of a condition set forth in Section 7.1 (Accuracy of Representations and Warranties) or Section 7.2 (Performance of Covenants) and (ii) cannot be or has not been cured within 30 days following receipt by Buyer of written notice of such material breach or failure to perform; provided, however, that Seller shall not have the right to terminate this Agreement pursuant to this Section 9.1(e) (Termination) if Seller is then in material breach of this Agreement.

9.2Effect of Termination. In the event of the termination of this Agreement as provided in Section 9.1 (Termination), this Agreement shall be of no further force or effect; provided, however, that (i) this Section 9.2 (Effect of Termination) and Section 10 (Miscellaneous Provisions) shall survive the termination of this Agreement and shall remain in full force and effect and (ii) nothing herein shall relieve any party from any liability for common law fraud or for a material breach of any covenant or agreement set forth in this Agreement that is the consequence of an action or failure to act by the breaching party with the knowledge that such action or failure to act would result in such material breach.

SECTION 10.Miscellaneous Provisions

10.1Amendment. This Agreement may not be amended except by an instrument in writing signed on behalf of Seller and Buyer.

10.2Expenses. All fees and expenses incurred in connection with this Agreement and the transactions contemplated by this Agreement shall be paid by the party incurring such expenses, whether or not the Sale is consummated.

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10.3Waiver.

(a)No failure on the part of any party to exercise any power, right, privilege or remedy under this Agreement, and no delay on the part of any party in exercising any power, right, privilege or remedy under this Agreement, shall operate as a waiver of such power, right, privilege or remedy; and no single or partial exercise of any such power, right, privilege or remedy shall preclude any other or further exercise thereof or of any other power, right, privilege or remedy.

(b)No party shall be deemed to have waived any claim arising out of this Agreement, or any power, right, privilege or remedy under this Agreement, unless the waiver of such claim, power, right, privilege or remedy is expressly set forth in a written instrument duly executed and delivered on behalf of such party; and any such waiver shall not be applicable or have any effect except in the specific instance in which it is given.

10.4Entire Agreement; Counterparts. This Agreement and the other Transaction Documents constitute the entire agreement and supersede all prior agreements and understandings, both written and oral, among or between any of the parties with respect to the subject matter hereof and thereof; provided, however, that the Confidentiality Agreement shall not be superseded and shall remain in full force and effect until the Closing. This Agreement may be executed in several counterparts, each of which shall be deemed an original and all of which shall constitute one and the same instrument. This Agreement may be executed by facsimile or electronic transmission, each of which shall be deemed an original.

10.5Applicable Law; Jurisdiction. This Agreement shall be governed by, and construed in accordance with, the laws of the State of New York, regardless of the Laws that might otherwise govern under applicable principles of conflicts of laws thereof. EXCEPT AS SET FORTH IN SECTION 1.6 (POST CLOSING ADJUSTMENT TO CLOSING PURCHASE PRICE) AND SECTION 1.7 (CONTINGENT CONSIDERATION), IN ANY ACTION BETWEEN ANY OF THE PARTIES ARISING OUT OF OR RELATING TO THIS AGREEMENT OR ANY OF THE TRANSACTIONS CONTEMPLATED BY THIS AGREEMENT, EACH OF THE PARTIES IRREVOCABLY AND UNCONDITIONALLY: (A) CONSENTS AND SUBMITS TO THE EXCLUSIVE JURISDICTION AND VENUE OF NEW YORK STATE COURT SITTING IN NEW YORK COUNTY OR, IF SUCH STATE COURT DOES NOT HAVE SUBJECT MATTER JURISDICTION, THE FEDERAL COURT SITTING IN NEW YORK COUNTY, NEW YORK; (B) WAIVES, TO THE FULLEST EXTENT PERMITTED BY LAW, ANY OBJECTION THAT IT MAY NOW OR HEREAFTER HAVE TO THE LAYING OF VENUE OF ANY SUCH ACTION IN ANY SUCH COURT OR THAT ANY SUCH ACTION BROUGHT IN ANY SUCH COURT HAS BEEN BROUGHT IN AN INCONVENIENT FORUM; AND (C) WAIVES THE RIGHT TO TRIAL BY JURY.

10.6Attorneys’ Fees. In any action at law or suit in equity to enforce this Agreement or the rights of any of the parties hereunder, the prevailing party in such action or suit shall be entitled to receive a reasonable sum for its attorneys’ fees and all other reasonable costs and expenses incurred in such action or suit.

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10.7Assignability. This Agreement shall be binding upon, and shall be enforceable by and inure solely to the benefit of, the parties hereto and their respective successors and assigns; provided, however, that, neither this Agreement nor any of the rights hereunder may be assigned (whether by merger, consolidation, sale or otherwise) by Seller or Buyer without the prior written consent of the other party, and any attempted assignment of this Agreement or any of such rights without such consent shall be void and of no effect except that, subject to Section 1.7(g) (Contingent Consideration), either Buyer or Seller may assign this Agreement or any such rights to an Affiliate without the prior written consent of the other party hereto; provided, further, however, that subject to Section 1.7(g) (Contingent Consideration), Buyer or Seller may assign this Agreement as a whole without such consent in connection with the acquisition (whether by merger, consolidation, sale or otherwise) of Buyer or Seller, as applicable, as long as Buyer or Seller, as applicable, provides written notice to the other party hereto of such assignment and the assignee thereof agrees in writing to assume and be bound as a party to this Agreement.

10.8Third Party Beneficiaries; No Recourse.

(a)Except as provided in Section 5.2 (Indemnification of Certain Persons), Section 8.1 (Indemnification of Buyer) Section 8.2 (Indemnification of Seller), Section 8.6(c) (Sole and Exclusive Remedy; Limitations), Section 10.12 (Conflict of Interest) and Section 10.14 (Acknowledgement), nothing in this Agreement, express or implied, is intended to or shall confer upon any Person (other than the parties hereto) any right, benefit or remedy of any nature whatsoever under or by reason of this Agreement.

(b)The parties to this Agreement agree on their own behalf and on behalf of their respective Subsidiaries and Affiliates that this Agreement may only be enforced against, and any action for breach of this Agreement may only be made against, the parties to this Agreement, and no NonRecourse Party of a party to this Agreement shall have any liability relating to this Agreement or any of the transactions contemplated herein.

10.9Notices. Any notice or other communication required or permitted to be delivered to any party under this Agreement shall be in writing and shall be deemed properly delivered, given and received (a) upon receipt when delivered by hand, (b) upon transmission, if sent by facsimile or electronic transmission (in each case with receipt verified by electronic confirmation), or (c) one Business Day after being sent by courier or express delivery service; provided that in each case the notice or other communication is sent to the address or facsimile telephone number set forth beneath the name of such party below (or to such other address or facsimile telephone number as such party shall have specified in a written notice given to the other parties hereto):

if to Buyer or, after the Closing, the Acquired Company:

Novo Nordisk A/S
Novo Alle 1
2880 Bagsværd
Denmark
Attention: Head of Business Development (with a copy to General Counsel)
Email: [***]

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with a copy to (which shall not constitute notice):

Davis Polk & Wardwell LLP

450 Lexington Avenue

New York, NY 10017

Attention: William H. Aaronson; David Bauer

Email: [***]

and

Matheson
Attention: David Fitzgibbon; John Coary
E-mail: [***]

if to Seller:

Prothena Biosciences Limited
77 Sir John Rogerson’s Quay, Block C, Grand Canal Docklands
Dublin 2, D02 VK60, Ireland
Attention: Director
Email: [***]

if to Parent:

Prothena Corporation Plc
77 Sir John Rogerson’s Quay, Block C, Grand Canal Docklands
Dublin 2, D02 VK60, Ireland
Attention: Chief Legal Officer and Company Secretary
Email: [***]

if, prior to Closing, to the Acquired Company:

Neotope Neurosciences Limited
77 Sir John Rogerson’s Quay, Block C, Grand Canal Docklands
Dublin 2, D02 VK60, Ireland
Attention: Director
Email: [***]

in each case with respect to Seller, Parent or, prior to Closing, the Acquired Company, with a copy to (which shall not constitute notice):

Prothena Biosciences Inc
331 Oyster Point Boulevard
South San Francisco, CA 94080 USA
Attention: Legal Department
Email: [***]

and

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Cooley LLP
4401 Eastgate Mall
San Diego, CA 92121
Attention: Barbara Borden; Marya Postner; Rowook Park
Facsimile: [***]
E-mail: [***]

and

A&L Goodbody
Attention: Alan Casey; Deirdre Geraghty
E-mail: [***]

10.10Severability. Any term or provision of this Agreement that is invalid or unenforceable in any situation in any jurisdiction shall not affect the validity or enforceability of the remaining terms and provisions hereof or the validity or enforceability of the offending term or provision in any other situation or in any other jurisdiction. If the final judgment of a court of competent jurisdiction declares that any term or provision hereof is invalid or unenforceable, the parties hereto agree that the court making such determination shall have the power to limit the term or provision, to delete specific words or phrases, or to replace any invalid or unenforceable term or provision with a term or provision that is valid and enforceable and that comes closest to expressing the intention of the invalid or unenforceable term or provision, and this Agreement shall be enforceable as so modified. In the event such court does not exercise the power granted to it in the prior sentence, the parties hereto agree to replace such invalid or unenforceable term or provision with a valid and enforceable term or provision that will achieve, to the extent possible, the economic, business and other purposes of such invalid or unenforceable term.

10.11Knowledge. “Knowledge” of Seller or Seller’s “Knowledge” shall [***]. With respect to matters involving Intellectual Property, Knowledge does not require that the Knowledge Individuals have conducted, obtain or have obtained any freedom-to-operate opinions or similar opinions of counsel or any Intellectual Property clearance searches, and no knowledge of any third-party Intellectual Property that would have been revealed by such inquiries, opinions or searches will be imputed to the Knowledge Individuals or the direct reports of any of the foregoing; provided that any such opinions or searches that have been conducted or obtained prior to the date of this Agreement will not be excluded from the term “Knowledge” as a result of this sentence.

10.12Conflict of Interest. If Seller so desires, without the need for any consent or waiver by the Acquired Company or Buyer, each of Cooley LLP (“Cooley”) or A&L Goodbody (“ALG”) shall be permitted to represent Seller after the Closing in connection with any matter, including without limitation, anything related to the transactions contemplated by this Agreement, any other agreements referenced herein or any disagreement or dispute relating thereto. Without limiting the generality of the foregoing, after the Closing, each of Cooley and ALG shall be permitted to represent Seller, any of their agents and Affiliates, or any one or more of them, in connection with any negotiation, transaction or dispute (including any litigation, arbitration or other adversary proceeding) with Buyer, the Acquired Company or any of their

52.

agents or Affiliates under or relating to this Agreement, any transaction contemplated by this Agreement, and any related matter, such as claims or disputes arising under other agreements entered into in connection with this Agreement, including with respect to any indemnification claims. Upon and after the Closing, the Acquired Company shall cease to have any attorney-client relationship with Cooley and ALG, unless and to the extent Cooley or ALG is specifically engaged in writing by the Acquired Company to represent the Acquired Company after the Closing and either such engagement involves no conflict of interest with respect to Seller or Seller consents in writing at the time to such engagement. Any such representation of the Acquired Company by Cooley or ALG after the Closing shall not affect the foregoing provisions hereof. Cooley and ALG shall be an express third-party beneficiary for such purposes.

10.13Attorney-Client Privilege. Buyer and Seller agree that any attorney-client privilege, attorney work-product protection, and the expectation of client confidence attaching as a result of counsel’s (whether external or internal) representation of the Acquired Company in connection with the transactions contemplated by this Agreement, including the Sale, and all information and documents covered by such privilege or protection (the “Covered Materials”), shall belong to and be controlled by Seller, and not by the Acquired Company, following the Closing, and may be waived only by Seller, and not the Acquired Company, and shall not pass to or be claimed or used by Buyer or the Acquired Company. Absent the consent of Seller, neither Buyer nor the Acquired Company shall have a right to access the Covered Materials following the Closing and, in the event Buyer or the Acquired Company accesses Covered Materials in violation of this sentence, such access will not waive or otherwise affect the rights of Seller with respect to the related privilege or protection. If a dispute arises between Buyer or the Acquired Company, on the one hand, and a third party other than (and unaffiliated with) Seller, on the other hand, after the Closing, then the Acquired Company may assert such attorney-client privilege to prevent disclosure to such Covered Materials; and provided, further, that Buyer and the Acquired Company may not waive such privilege without the prior written consent of Seller.

10.14Acknowledgement.

(a)Buyer is acquiring the Shares for investment for its own account and not with a view to, or for sale in connection with, any distribution of any part thereof. Buyer acknowledges that the Shares and the sale thereof have not been registered under the Laws of any jurisdiction.

(b)Buyer is not relying and Buyer has not relied on any representations or warranties whatsoever regarding the subject matter of this Agreement, express or implied, except for the representations and warranties expressly set forth in Section 2 (Representations and Warranties of Seller). Such representations and warranties by Seller constitute the sole and exclusive representations and warranties of Seller in connection with the transactions contemplated hereunder and Buyer understands, acknowledges and agrees that all other representations and warranties of any kind or nature whether express, implied or statutory are specifically disclaimed by Seller.

(c)In connection with the due diligence investigation of Seller and the Acquired Company by Buyer and its Affiliates, stockholders, directors, officers, employees, agents, representatives or advisors, Buyer and its Affiliates, stockholders,

53.

directors, officers, employees, agents, representatives and advisors have received and may continue to receive after the date hereof from Seller and its Affiliates, shareholders, directors, officers, employees, consultants, agents, representatives and advisors (each of whom shall be an express third-party beneficiary hereof) certain estimates, projections, forecasts and other forward-looking information, as well as certain business plan information, regarding Seller or the Acquired Company and their respective businesses and operations. Buyer hereby acknowledges that there are uncertainties inherent in attempting to make such estimates, projections, forecasts and other forward-looking statements, as well as in such business plans, and that Buyer will have no claim against Seller, or any of its Affiliates, shareholders, directors, officers, employees, consultants, agents, representatives or advisors, or any other Person, with respect thereto. Accordingly, Buyer hereby acknowledges and agrees that, except for the representations and warranties expressly set forth in Section 2 (Representations and Warranties of Seller) of this Agreement, neither Seller, nor any of its Affiliates, shareholders, directors, officers, employees, consultants, agents, representatives or advisors has made or is making any express or implied representation or warranty with respect to such estimates, projections, forecasts, forward-looking statements or business plans.

10.15Specific Performance. Each of the parties hereto agrees that this Agreement is intended to be legally binding and specifically enforceable pursuant to its terms and that Buyer and Seller would be irreparably harmed if any of the provisions of this Agreement are not performed in accordance with their specific terms and that monetary damages would not provide adequate remedy in such event. Accordingly, in addition to any other remedy to which a non-breaching party may be entitled at law, a non-breaching party shall be entitled to seek injunctive relief to prevent breaches of this Agreement and to specifically enforce the terms and provisions hereof, in each case without posting a bond or undertaking, this being in addition to any other remedy to which they are entitled at law or in equity.

10.16Construction.

(a)For purposes of this Agreement, whenever the context requires: the singular number shall include the plural, and vice versa; the masculine gender shall include the feminine and neuter genders; the feminine gender shall include the masculine and neuter genders; and the neuter gender shall include masculine and feminine genders.

(b)The parties hereto agree that any rule of construction to the effect that ambiguities are to be resolved against the drafting party shall not be applied in the construction or interpretation of this Agreement.

(c)As used in this Agreement, the words “include” and “including,” and variations thereof, shall not be deemed to be terms of limitation, but rather shall be deemed to be followed by the words “without limitation.”

(d)Except as otherwise indicated, all references in this Agreement to “Sections,” “Exhibits” and “Schedules” are intended to refer to Sections of this Agreement and Exhibits or Schedules to this Agreement.

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(e)The bold-faced headings contained in this Agreement are for convenience of reference only, shall not be deemed to be a part of this Agreement and shall not be referred to in connection with the construction or interpretation of this Agreement.

(f)Any document uploaded to the online data room utilized for the transactions contemplated by this Agreement on or prior to the date of this Agreement shall be considered “made available”, “furnished”, “delivered” or “provided” for purposes of this Agreement.

(g)Unless the context requires otherwise, the word “or” shall be inclusive such that for example, “A or B” shall be deemed to mean “A or B or both A and B.”

10.17Disclosure Schedule. The Disclosure Schedule has been arranged, for purposes of convenience only, as separate parts corresponding to the subsections of Section 2 (Representations and Warranties of Seller) of this Agreement. The representations and warranties contained in Section 2 (Representations and Warranties of Seller) of this Agreement are subject to (a) the exceptions and disclosures set forth in the part of the Disclosure Schedule corresponding to the particular subsection of Section 2 (Representations and Warranties of Seller) in which such representation and warranty appears; (b) any exceptions or disclosures explicitly cross-referenced in such part of the Disclosure Schedule by reference to another part of the Disclosure Schedule; and (c) any exception or disclosure set forth in any other part of the Disclosure Schedule to the extent it is reasonably apparent on the face of such disclosure that such exception or disclosure is intended to qualify such representation and warranty. No reference to or disclosure of any item or other matter in the Disclosure Schedule shall be construed as an admission or indication that such item or other matter is material (nor shall it establish a standard of materiality for any purpose whatsoever) or that such item or other matter is required to be referred to or disclosed in the Disclosure Schedule. The information set forth in the Disclosure Schedule is disclosed solely for the purposes of this Agreement, and no information set forth therein shall be deemed to be an admission by any party hereto to any third party of any matter whatsoever, including of any violation of Law or breach of any agreement. The Disclosure Schedule and the information and disclosures contained therein are intended only to qualify and limit the representations, warranties and covenants of Seller contained in this Agreement. Nothing in the Disclosure Schedule is intended to broaden the scope of any representation or warranty contained in this Agreement or create any covenant. Matters reflected in the Disclosure Schedule are not necessarily limited to matters required by the Agreement to be reflected in the Disclosure Schedule. Such additional matters are set forth for informational purposes and do not necessarily include other matters of a similar nature.

[Signature Page Follows]

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In Witness Whereof, the parties have caused this Agreement to be executed as of the date first above written.

Novo Nordisk A/S

By: /s/ Karsten Munk Knudsen

Name: Karsten Munk Knudsen

Title: Executive Vice President

By: /s/ Marcus Schindler

Name: Marcus Schindler

Title: Executive Vice President

[Signature Page to Share Purchase Agreement]

In Witness Whereof, the parties have caused this Agreement to be executed as of the date first above written.

Novo Nordisk Region Europe A/S

By: /s/ Karsten Munk Knudsen

Name: Karsten Munk Knudsen

Title: Executive Vice President

By: /s/ Tomas Haagen

Name: Tomas Haagen

Title: Board member

[Signature Page to Share Purchase Agreement]

In Witness Whereof, the parties have caused this Agreement to be executed as of the date first above written.

Prothena Biosciences Limited

By: /s/ Yvonne Tchrakian

Name: Yvonne M. Tchrakian

Title: Director & Company Secretary

[Signature Page to Share Purchase Agreement]

In Witness Whereof, the parties have caused this Agreement to be executed as of the date first above written.

Prothena Corporation Plc

By: /s/ Shane Cooke

Name: Shane Cooke

Title: Director

[Signature Page to Share Purchase Agreement]

Exhibit A

Certain Definitions

For purposes of the Agreement (including this Exhibit A):

“Accounting Principles” shall mean (i) IFRS as in effect at the date of the financial statement to which it refers, or if there is no such financial statement, then as of the Closing Date, using and applying the same accounting principles, practices, procedures, policies and methods (with consistent classifications, judgments, elections, inclusions, exclusions and valuation and estimation methodologies) used and applied by the Acquired Company in the preparation of the Audited Financial Statements and consistently applied in all material respects to the Unaudited Balance Sheet, subject to normal and recurring year-end adjustments and (ii) if such accounting principles, practices, procedures, policies and methods and IFRS are inconsistent, the accounting principles, practices, procedures, policies and methods used in the preparation of the Audited Financial Statement shall control; provided, further, that Accounting Principles (A) shall not include any purchase accounting or other adjustment arising out of the consummation of the transactions contemplated by this Agreement, (B) shall be based on facts and circumstances as they exist prior to the Closing and shall exclude the effect of any act, decision or event occurring on or after the Closing, (C) shall follow the defined terms contained in this Agreement and (D) shall calculate any reserves, accruals or other non-cash expense items on a pro rata (as opposed to monthly accrual) basis to account for a Closing that occurs on any date other than the last day of a calendar month.

“Accounts Relief” means (a) any Relief (including the right to a repayment of Tax shown as an asset in the Unaudited Balance Sheet, or (b) any Relief the availability of which has been taken into account in computing (and so reducing or eliminating) any provision for deferred Tax in the Unaudited Balance Sheet.

“Acquired Company” shall have the meaning set forth in the recitals of this Agreement.

“Acquired Company Returns” shall mean any Tax Return required to be filed by the Acquired Company.

“Adjustment Amount” shall have the meaning set forth in Section 1.6(g) (Post Closing Adjustment to Closing Purchase Price).

“Affiliate” shall mean, with respect to any specified Person, any other Person that, directly or indirectly, through one or more intermediaries, controls, is controlled by or is under common control with such specified Person. For the avoidance of doubt, the Acquired Company shall be deemed for purposes of this Agreement to be an Affiliate of Seller prior to the Closing and an Affiliate of Buyer from and after the Closing. For purposes of this definition, “control” when used with respect to any Person means the power to direct the management and policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise, and the terms “controlling” and “controlled” have correlative meanings under this Agreement.

“Agreement” shall have the meaning set forth in the preamble of this Agreement.

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“ALG” shall have the meaning set forth in Section 10.12 (Conflict of Interest).

[***]

“Annual Net Sales” shall mean all Net Sales of any Milestone Product invoiced by the Milestone Obligors in any calendar year.

“Anti-Corruption Laws” shall mean the Foreign Corrupt Practices Act of 1977, as amended, or any other comparable Law applicable in the United States or any non-U.S. jurisdiction, in each case as applicable and together with the related regulations and published interpretations thereunder.

“Antitrust Laws” shall mean the Sherman Act, as amended, the Clayton Act, as amended, the Hart-Scott-Rodino Anti-Trust Improvements Act of 1976, as amended, the Irish Criminal Justice (Corruption Offences) Act 2018, as amended, and all other federal, state and foreign statutes, rules, regulations, orders, decrees, and other Laws that are designed or intended to prohibit, restrict or regulate actions having the purpose or effect of monopolization or restraint of trade or competition.

[***]

“ATTR Indication” means the prevention, treatment, amelioration or cure of any cardiomyopathy including [***].

“Audited Financial Statements” shall have the meaning set forth in Section 2.4 (Financial Statements).

“Balance Sheet Date” shall have the meaning set forth in Section 2.4 (Financial Statements).

“Base Purchase Price” shall mean $60,000,000.

“Business” shall have the meaning set forth in Section 2.2(a) (Assets of the Acquired Company; Sufficiency of Assets).

“Business Day” shall mean any day that is not a Saturday, a Sunday or other day on which banks are required or authorized by Law to be closed in Dublin, Ireland or New York, New York.

“Buyer” shall have the meaning set forth in the preamble of this Agreement.

“Buyer Indemnified Party” shall have the meaning set forth in Section 8.1 (Indemnification of Buyer).

“Buyer Prepared Return” shall have the meaning set forth in Section 5.4(a) (Tax Matters).

“Buyer’s Relief” means (a) any Accounts Relief, (b) any Relief which arises to the Acquired Company as a result of or in connection with any event occurring after Closing or

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profits earned, accrued or received after Closing, and (c) any Relief arising to Buyer or any Affiliate of Buyer (excluding the Acquired Company) at any time.

“Cash and Cash Equivalents” shall mean, without duplication, with respect to the Acquired Company, as of the Reference Time (but before taking into account the consummation of the transactions contemplated hereby), the aggregate amount of cash, cash equivalents and marketable securities held by the Acquired Company, as determined in accordance with the Accounting Principles, whether or not kept “on site” or held in deposit, checking, savings, brokerage or other accounts of or in any safety deposit box or other storage device, less (a) the aggregate amount of outstanding checks or drafts of the Acquired Company that have not posted, plus (b) checks received by the Acquired Company that have not been posted, less (c) the aggregate amount of all cash or cash equivalents that are not freely usable, distributable or transferrable (including any security deposits, amounts held in collateral, and cash and cash equivalents held in escrow or on behalf of third parties but excluding anything in clause (b)) by the Acquired Company.

“Change of Law” shall have the meaning set forth in Section 8.9 (Change of Law).

“Claim Notice” shall have the meaning set forth in Section 8.3 (Third-Party Claims).

“Clinical Development Plan” shall mean the Clinical Development Plan substantially in the form attached hereto as Exhibit B; as may be modified from time-to-time by Buyer.

“Closing” shall have the meaning set forth in Section 1.3 (Closing; Closing).

“Closing Date” shall have the meaning set forth in Section 1.3 (Closing; Closing).

“Closing Date Cash Amount” shall mean the Cash and Cash Equivalents of the Acquired Company as of the Reference Time determined in accordance with the Accounting Principles.

“Closing Date Indebtedness” shall mean the Debt of the Acquired Company, including Debt pursuant to an Intercompany Contract, as of the Reference Time determined in accordance with the Accounting Principles.

“Closing Date Transaction Expenses” shall mean, without duplication, all costs, fees, expenses and other amounts incurred by or on behalf of, or that are payable or due from, the Acquired Company, in each case from arrangements or agreements entered into prior to the Closing, arising out of or in connection with the performance by Seller or any of its Affiliates of Seller’s obligations under this Agreement, the negotiation and execution of this Agreement and the other Transaction Documents, and the consummation of the transactions contemplated by this Agreement, including (i) the aggregate expenses, fees and disbursements of all transaction advisors, financial advisors, valuation experts, data room administrators, brokers, finders, investment bankers, attorneys, accountants and other consultants and advisors of Seller or any of its Affiliates in connection with the negotiation, execution, delivery and performance of this Agreement through the Closing, including Cooley and ALG, (ii) any concession or other similar fee that the Acquired Company agrees prior to Closing to pay any Person in connection with obtaining such Person’s consent under any Contract, (iii) the costs, fees and expenses incurred by the Acquired Company under any Intercompany Contract in order to terminate any Intercompany

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Contract as contemplated hereby (but excluding any outstanding debt under any Intercompany Contract, which will be treated as Closing Date Indebtedness hereunder), (iv) any nonrefundable value added Tax incurred by the Acquired Company in connection with, or relating to the fees, costs, payments and expenditures set forth above, and (v) costs, fees, expenses and other amounts incurred by the Acquired Company or Seller in connection with the transaction process that resulted in the execution of this Agreement, in each case to the extent that Seller or the Acquired Company is responsible for such fees, expenses and disbursements and such fees, expenses and disbursements have not been paid by Seller or the Acquired Company prior to the Closing or paid by Seller after the Closing; provided, however, that Closing Date Transaction Expenses shall not include any Taxes (other than those Taxes listed in clause (iv) above).

“Closing Purchase Price” shall mean cash in an amount equal to:

(a)the Base Purchase Price;

(b)plus the Estimated Closing Date Cash Amount, subject to adjustment as provided in Section 1.6 (Post Closing Adjustment to Closing Purchase Price);

(c)minus the Estimated Closing Date Indebtedness, subject to adjustment as provided in Section 1.6 (Post Closing Adjustment to Closing Purchase Price); and

(d)minus the Estimated Closing Date Transaction Expenses, subject to adjustment as provided in Section 1.6 (Post Closing Adjustment to Closing Purchase Price).

“Closing Statement” shall have the meaning set forth in Section 1.6(b) (Post Closing Adjustment to Closing Purchase Price).

“CMC” means chemistry, manufacturing and controls for the manufacturing of a biologic pharmaceutical product.

“Code” shall mean the Internal Revenue Code of 1986, as amended.

“Company Financial Statements” shall have the meaning set forth in Section 2.4 (Financial Statements).

“Company Intellectual Property” shall mean any and all Intellectual Property that is owned or purported to be owned by the Acquired Company.

“Company Licensed Intellectual Property” shall mean any and all Intellectual Property that is licensed or purported to be licensed to the Acquired Company or for which the Acquired Company has obtained or purported to have obtained a covenant not to be sued.

“Company Material Adverse Effect” shall mean any effect that is materially adverse to the assets, financial condition or existing business of the Acquired Company; provided, however, that none of the following (individually or in combination) shall be deemed to constitute, or shall be taken into account in determining whether there has been, a Company Material Adverse Effect: (a) any adverse effect resulting directly or indirectly from general business or economic conditions, except to the extent such general business, political or economic conditions have a

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disproportionate effect on the Acquired Company as compared to any of the other companies in the Acquired Company’s industry; (b) any adverse effect resulting directly or indirectly from conditions generally affecting any industry or industry sector in which the Acquired Company operates or competes, except to the extent such adverse effect has a disproportionate effect on the Acquired Company as compared to any of the other companies in such industry or industry sector; (c) any adverse effect resulting directly or indirectly from acts of war, sabotage, terrorism or natural acts, including hurricanes, earthquakes, floods, tsunamis, tornadoes, mudslides, fires or other disasters, epidemics, pandemic (including COVID-19) and other force majeure events; (d) any adverse effect resulting directly or indirectly from matters set forth in the Disclosure Schedule or the announcement, execution, delivery or performance of this Agreement or the pendency or consummation of the Sale, including any disruption in (or loss of) supplier, service provider, partner or similar relationships or any loss of consultants or contractors (other than for purposes of any representation or warranty contained in Section 2.18 (Non-Contravention; Consents) but subject to disclosures in Section 2.18 of the Disclosure Schedule); (e) any adverse effect resulting directly or indirectly from any change in accounting requirements or principles or any change in applicable Laws or the interpretation thereof; (f) any adverse effect resulting directly or indirectly from any action taken by Seller or the Acquired Company at Buyer’s express instruction or direction; (g) the failure of Seller or the Acquired Company to meet internal expectations or projections; (h) the results of, or any data derived from, any preclinical or clinical testing being conducted by or on behalf of any competitor of the Acquired Company or any of their respective collaboration partners or any announcement thereof; (i) increased incidence or severity of any previously identified side effects, adverse events or safety observations, or reports of new side effects, adverse events or safety observations, with respect to any products or product candidates of any competitors of the Acquired Company; (j) any recommendations, statements or other pronouncements published or proposed by professional medical organizations or any Governmental Body, or any panel or advisory body empowered or appointed thereby, relating to any products or product candidates of any competitors of the Acquired Company; (k) any supply chain disruption affecting products or product candidates of the Acquired Company or any products or product candidates of any competitors of the Acquired Company; (l) any determination or development relating to coverage, reimbursement or payor rules or policies applicable to, or pricing of, any products or product candidates of the Acquired Company or any products or product candidates of any competitors of the Acquired Company; or (m) any adverse effect resulting directly or indirectly from any breach by Buyer of any provision of this Agreement or the taking of any other action by Buyer.

“Company Patent” shall mean any Patent Rights (a) included in the Company Intellectual Property and existing as of the Closing or (b) included in the Company Licensed Intellectual Property exclusively licensed to the Acquired Company and existing as of the Closing.

“Comparable Entity” shall mean an Entity that is one of [***].

“Compound” shall mean the [***] monoclonal antibody being developed by the Acquired Company as of the Closing under the designation PRX004 and [***].

“Confidentiality Agreement” shall mean that certain Mutual Confidentiality Agreement, [***], by and between Buyer and the Acquired Company.

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“Contract” shall mean any contract, plan, undertaking, arrangement, concession, understanding, agreement, agreement in principle, franchise, permit, instrument, license, lease, sublease, note, bond, indenture, deed of trust, mortgage, loan agreement that is or purports to be a binding commitment, whether written or oral, including any exhibits, annexes, appendices or attachments thereto, and any amendments, modifications, supplements, extension or renewals thereof.

“Controlling Party” shall have the meaning set forth in Section 8.3 (Third-Party Claims).

“Cooley” shall have the meaning set forth in Section 10.12 (Conflict of Interest).

“Cover” shall mean, with respect to any product and any claim of any Patent Right, that such claim of such Patent Right would be infringed (or if such claim is in a pending Patent Right application, such claim would be infringed if it were issued), absent a license, by the use, manufacture, offer for sale, sale or importation or other exploitation of such product. “Covered” has a correlative meaning.

“Covered Materials” shall have the meaning set forth in Section 10.13 (Attorney-Client Privilege).

“COVID-19” shall mean SARS-CoV-2 or COVID-19.

“COVID-19 Measures” shall mean any quarantine, “shelter in place,” “stay at home,” workforce reduction, social distancing, shut down, closure, sequester, safety or similar Law, directive or guidelines promulgated by any Governmental Body, including the Centers for Disease Control and Prevention and the World Health Organization, intended to ensure the health and safety of the general public in light of COVID-19, in each case, in response to COVID-19, including the Families First Act.

“Damages” shall mean losses, costs, damages, liabilities, fines, deficiencies, fees, charges, penalties, judgment, costs, amounts paid in settlement and expenses, including reasonable out-of-pocket attorneys’ fees and expenses and reasonable fees and expenses of other professionals and experts, that have been incurred or properly paid by an Indemnified Party, including investigation, litigation or other proceedings related fees and expenses; provided, however, that (a) “Damages” shall not include any unforeseeable, speculative, special, indirect, exemplary and punitive damages (except to the extent paid or payable by an Indemnified Party to a third party in connection with a Third-Party Claim); (b) for purposes of computing the amount of Damages incurred or paid by a Person, there shall be deducted an amount equal to the amount of any insurance proceeds, indemnification payments, contribution payments, reimbursements or refunds that are received by such Person or any of such Person’s Affiliates in connection with such Damages or the circumstances giving rise thereto; and (c) Damages shall include any costs incurred in connection with any reasonable steps taken to mitigate any Damages hereunder.

“Data Protections Laws” means all applicable data protection law including the GDPR, the Data Protection Acts 1988 to 2018 and any other legislation which implements the GDPR, the European Communities (Electronic Communications Networks and Services) (Privacy and Electronic Communications) Regulations 2011 and any other legislation which implements the Electronic Communications Data Protection Directive (2002/58/EC), all applicable Irish laws

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and regulations relating to the processing of personal data and privacy, any compulsory guidance and codes of practice issued by the Data Protection Commission or the European Data Protection Board and all applicable similar or related legislation in any competent jurisdiction and prior to 25 May 2018, the Data Protection Acts 1988 to 2003, as amended.

“Deemed Tax Liability” means (a) the loss, otherwise than by use or setting-off, of any Accounts Relief in which case the amount of the Tax liability shall be the amount of (i) Tax which would (on the basis of Tax rates current at the Closing Date) have been saved but for such loss assuming that the Acquired Company had sufficient profits or was otherwise in a position to use the Relief; or (ii) the repayment, where the Relief is a right to a repayment of Tax, and (b) the use or setting-off of any Buyer’s Relief in circumstances where, but for such use or setting-off, the Acquired Company would have had a liability to make an actual payment of, or in respect of, Tax in respect of which Seller would have been liable to a claim under Sections 8.1(a), 8.1(b) and 8.1(c) of this Agreement, in which case the amount of the Tax liability shall be the amount for which Seller would have been liable under this Agreement but for such utilization or set-off.

“Debt” shall mean the outstanding principal amount of, and all interest and other amounts accrued in respect of, and all amounts payable at retirement of, (a) any indebtedness for borrowed money of the Acquired Company, (b) any obligation of the Acquired Company evidenced by bonds, debentures, notes or other similar instruments, (c) any reimbursement obligations of the Acquired Company with respect to letters of credit (including standby letters of credit to the extent drawn upon), bankers’ acceptances or similar facilities issued for the account of the Acquired Company, (d) non-cancellable purchase commitments, (e) trade payables, other current liabilities and accrued expenses, (f) any capital leases, (g) any obligation of the type referred to in clauses (a) through (f) of another Person the payment of which the Acquired Company has guaranteed or for which the Acquired Company is responsible or liable, directly or indirectly, jointly or severally, as obligor or guarantor and (h) all accrued and unpaid Liabilities for income Taxes of the Acquired Company calculated as of the occurrence of Closing on the Closing Date (in the case of a Straddle Period, pursuant to the methodology set forth in the definition of “Pre-Closing Taxes”). “Debt” shall not include (i) any letters of credit to the extent not drawn upon, (ii) any bank guarantees, (iii) surety bonds and performance bonds, and (iv) [***]. For purposes of Section 1 (Description of Transaction), “Debt” shall mean Debt of the Acquired Company, as defined above, outstanding as of the Reference Time (but before taking into account the consummation of the transactions contemplated by this Agreement).

“Development and Commercialization Milestone Event” shall have the meaning set forth in Section 1.7(a) (Contingent Consideration).

“Diligent Efforts” shall mean, with respect to the efforts to be expended by Buyer and each Milestone Obligor with respect to the development (including receipt of Regulatory Approval and, where applicable, Pricing Approval), manufacture and commercialization of a Milestone Product, the carrying out of such activities using efforts and resources that a pharmaceutical company of the size and resources of Buyer would reasonably devote, consistent with the exercise of prudent scientific and business judgment, to carrying out development, manufacturing and commercialization activities for compounds or products of similar market potential or strategic importance at a similar stage in development or product life as such

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Milestone Product, in each case taking into reasonable account actual or reasonably expected to occur issues [***].

“Disclosure Schedule” shall mean the disclosure schedule that has been prepared by Seller and delivered or made available to Buyer on the date of the Agreement. The contents of each of the Contracts and other documents referred to in the Disclosure Schedule shall be deemed to be incorporated and referred to in the Disclosure Schedule as though set forth in full therein.

“Dispute Auditor” shall have the meaning set forth in Section 1.6(d) (Post Closing Adjustment to Closing Purchase Price).

“Dispute Notice” shall have the meaning set forth in Section 1.6(c) (Post Closing Adjustment to Closing Purchase Price).

“EMA” shall mean the European Medicines Agency and any successor agency thereto.

“Employee Benefit Plan” means any (i) “employee benefit plan” as defined in Section 3(3) of ERISA, (ii) compensation, employment, consulting, severance, termination protection, change in control, transaction bonus, retention or similar plan, agreement, arrangement, program or policy or (iii) other plan, agreement, arrangement, program or policy providing for bonuses, profit-sharing, equity or equity-based compensation or other forms of incentive or deferred compensation, vacation benefits, insurance (including any self-insured arrangement), medical, dental, vision, prescription or fringe benefits, life insurance, relocation or expatriate benefits, perquisites, disability or sick leave benefits, employee assistance program, workers’ compensation, supplemental unemployment benefits or post-employment or retirement benefits (including pension, health, medical or insurance benefits), any pension, retirement or death benefit schemes or similar schemes or arrangements, in each case whether or not written (x) that is sponsored, maintained, administered, contributed to or entered into by the Acquired Company for the current or future benefit of any current or former employee or director or individual independent contractor or (y) for which the Acquired Company has any direct or indirect liability. For the avoidance of doubt, a collective bargaining or other labor agreement shall constitute an agreement for purposes of clauses (ii) and (iii).

“End Date” shall mean the date that is [***] from the date of this Agreement.

“Entity” shall mean any corporation (including any nonprofit corporation), general partnership, limited partnership, limited liability partnership, joint venture, estate, trust, company (including any limited liability company or joint stock company), firm or other enterprise, association, organization or entity.

“ERISA” shall mean the Employee Retirement Income Security Act of 1974, as amended.

“Estimated Closing Date Cash Amount” shall have the meaning set forth in the definition of “Estimated Closing Statement” in this Exhibit A.

“Estimated Closing Date Indebtedness” shall have the meaning set forth in the definition of “Estimated Closing Statement” in this Exhibit A.

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“Estimated Closing Date Transaction Expenses” shall have the meaning set forth in the definition of “Estimated Closing Statement” in this Exhibit A.

“Estimated Closing Statement” shall mean a written statement, signed by an authorized representative of Seller, setting forth in reasonable detail Seller’s good faith estimate of the Closing Purchase Price, including (a) the Closing Date Cash Amount (the “Estimated Closing Date Cash Amount”), (b) the Closing Date Indebtedness (the “Estimated Closing Date Indebtedness”), and (c) the Closing Date Transaction Expenses (the “Estimated Closing Date Transaction Expenses”).

“European Union” shall mean (a) all countries that are officially recognized as member states of the European Union at any particular time and (b) the United Kingdom.

“FDA” shall mean the United States Food and Drug Administration and any successor agency thereto.

“FDCA” means the Federal Food, Drug, and Cosmetic Act of 1938, as amended, and the regulations promulgated thereunder.

[***]

“GDPR” shall mean (as the context permits) the EU General Data Protection Regulation (EU 2016/679) or the General Data Protection Regulation as adopted in the UK pursuant to the European Union (Withdrawal Act) 2018.

“Government Official” shall mean (a) any officer or employee of any Governmental Body, (b) any Person acting in an official capacity on behalf of a Governmental Body, (c) any officer or employee of a Person that is majority or wholly owned by a Governmental Body, (d) any officer or employee of a public international organization, such as the World Bank or the United Nations, (e) any officer or employee of a political party or any Person acting in an official capacity on behalf of a political party or (f) any candidate for political office.

“Governmental Body” shall mean any national, federal, regional, state, provincial, local or foreign or other governmental authority or instrumentality, legislative body, court, administrative agency, regulatory body, commission or instrumentality, including any multinational authority having governmental or quasi-governmental powers, or any other industry self-regulatory authority.

“IFRS” shall mean the International Financial Reporting Standards as issued by the International Accounting Standards Board or any successor thereto and in accordance with IFRS as endorsed by the European Union. With respect to the computations pursuant to Section 1.6 (Post Closing Adjustment to Closing Purchase Price), IFRS shall mean such principles as in effect as of the Reference Time.

“Indemnification Demand” shall have the meaning set forth in Section 8.4(a) (Indemnification Mechanics).

“Indemnification Dispute Notice” shall have the meaning set forth in Section 8.4(b) (Indemnification Mechanics).

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“Indemnified Party” shall mean the Person entitled to indemnification under Section 8 (Indemnification).

“Indemnifying Parties” shall have the meaning set forth in Section 5.2(b) (Indemnification of Officers and Directors).

“Indemnified Persons” shall have the meaning set forth in Section 5.2(a) (Indemnification of Officers and Directors).

“Indemnity Cap” shall have the meaning set forth in Section 8.6(d) (Sole and Exclusive Remedy; Limitations).

“Indemnity Deductible” shall have the meaning set forth in Section 8.6(f) (Sole and Exclusive Remedy; Limitations).

“Initiation” shall mean, with respect to a particular clinical trial, dosing of fifth (5th) patient in such trial. “Initiates” shall have a correlative meaning.

“Insurance Policies” shall have the meaning set forth in Section 2.15 (Insurance).

“Intellectual Property” shall mean any and all intellectual property and similar proprietary rights in any jurisdiction throughout the world, including:

(a)all issued or granted patents (including all utility, utility model and design patents), pending patent applications (including all provisionals, nonprovisionals, national, regional and international applications, as well as original, continuation, continuation-in-part, divisional and continued prosecution applications, reissues, renewals, reversions, extensions and re-examination applications), statutory invention registrations and any term extension or other action by a Governmental Body which provides rights beyond the original expiration date of any of the foregoing, whether within or outside the United States (“Patent Rights”);

(b)trademarks, service marks, logos, trade names and trade dress, whether or not registered, and all pending applications for registration of the same, other than regulatory filings;

(c)copyrights, whether or not registered, and all pending applications for registration of the same;

(d)domain names and URLs;

(e)trade secrets and other rights in know-how (including inventions) and confidential or proprietary information;

(f)computer programs and databases, whether in object or source code form;

(g)registrations and applications for, and all goodwill associated with, any and all of the foregoing; and

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(h)rights to sue and recover and retain damages, costs and attorneys’ fees for past, present or future infringement, misappropriation or violation of any and all of the foregoing.

“Intercompany Contract” shall mean Contracts between Seller or any of its Affiliates (other than the Acquired Company), on the one hand, and the Acquired Company, on the other hand.

“Irish Companies Act” means the Companies Act 2014 and all orders, statutory instruments and regulations made thereunder and intended to be construed as one with the Companies Act 2014.

“Joint Press Release” shall have the meaning set forth in Section 5.3 (Disclosure).

“Knowledge” shall have the meaning set forth in Section 10.11 (Knowledge).

“Knowledge Individuals” shall mean the following Persons: [***].

“Law” shall mean any federal, state, local, municipal, foreign or other law, statute, constitution, principle of common law, ordinance, code, edict, decree, rule, regulation, ruling or requirement issued, enacted, adopted, promulgated, implemented or otherwise put into effect by or under the authority of any Governmental Body.

“Legal Proceeding” shall mean any action, suit, litigation, arbitration, proceeding (including any civil, criminal, administrative, investigative or appellate proceeding), hearing, inquiry, audit, examination or investigation commenced, brought, conducted or heard by or before, or otherwise involving, any court or other Governmental Body or any arbitrator or arbitration panel.

“Lien” or “Liens” shall mean all mortgages, liens, encumbrances, security interests, licenses, claims, charges or pledges, or other similar adverse claim of any kind in respect of such property or asset, including any restriction on the right to vote, sell or otherwise dispose of any capital stock or other voting or equity interest.

“Major Market Country” shall mean [***].

“Material Contract” shall have the meaning set forth in Section 2.9(a) (Material Contracts).

“Milestone Event” shall have the meaning set forth in Section 1.7(a) (Contingent Consideration).

“Milestone Notice” shall have the meaning set forth in Section 1.7(a) (Contingent Consideration).

“Milestone Obligor” shall mean each of (a) Buyer or any of its Subsidiaries or Affiliates (including as of immediately following the Closing, the Acquired Company), (b) any Transferee, and (c) with respect to a Milestone Product, any of their direct or indirect successors, licensees, sublicensees (including partners and collaborators that are licensees or sublicensees) or assignees

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of such Milestone Product or any other Person that has been granted the right to develop or commercialize such Milestone Product for its own account (rather than on behalf of Buyer, any of its Subsidiaries or Affiliates, or any Transferee).

“Milestone Payment(s)” shall have the meaning set forth in Section 1.7(a) (Contingent Consideration).

“Milestone Products” shall mean the PRX004 Milestone Products and Other Milestone Products.

“Net Sales” shall mean the gross amount invoiced by Milestone Obligors for sale of the Milestone Products less the following deductions to the extent (i) [***] and (ii) [***] with respect to such Milestone Product by, and not otherwise recovered or reimbursed to, the Milestone Obligors: [***].

Net Sales shall be calculated in accordance with IFRS, as consistently applied by the applicable Milestone Obligor. For clarity, if a single item falls into more than one of the categories set forth in clauses (a) to (d) above, such item may not be deducted more than once. Net Sales shall not include: [***].

With respect to any sale of any Milestone Product in a given country for any substantive consideration other than [***], for purposes of calculating the Net Sales under this Agreement, such Milestone Product shall be deemed to be sold [***].

In the event one or more Milestone Product(s) is/are sold together with one or more other active ingredients at a single price (such combination is hereinafter referred to as “Combination Product” and such other active ingredients, “Other Products”), such single price shall be allocated among the Milestone Product(s) and the Other Product(s) in the Combination Product based on the market price for such Milestone Product(s) and Other Product(s) when sold separately in the applicable country or jurisdiction. If any such Milestone Product or Other Product in a Combination Product is not being sold alone with a market price in the applicable country or jurisdiction, Buyer and Seller shall [***].

“Net Sales Milestone Event” shall have the meaning set forth in Section 1.7(a) (Contingent Consideration).

“NMPA” shall mean the National Medical Products Administration of China, and any successor agency thereto.

“NNRE” shall have the meaning set forth in the preamble of this Agreement.

“Non-Controlling Party” shall have the meaning set forth in Section 8.3 (Third-Party Claims).

“Non-Qualified Damages” shall have the meaning set forth in Section 8.6(f) (Sole and Exclusive Remedy; Limitations).

“Non-Recourse Party” shall mean, with respect to a party to this Agreement, any of such party’s former, current and future equity holders, controlling Persons, directors, officers,

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employees, agents, representatives, Affiliates, members, managers, general or limited partners, or assignees (or any former, current or future equity holder, controlling Person, director, officer, employee, agent, representative, Affiliate, member, manager, general or limited partner, or assignee of any of the foregoing); provided that, for the avoidance of doubt, no party to this Agreement will be considered a Non-Recourse Party.

“Novo Nordisk” shall have the meaning set forth in the preamble of this Agreement.

“Other Indication” means the prevention, treatment, amelioration or cure of any indication, disease or medical condition other than the ATTR Indication.

“Other Milestone Product” means any product candidate or product being developed or commercialized by or on behalf of any Milestone Obligor (other than a PRX004 Milestone Product) [***] is Covered by a Valid Claim contained in any (a) Company Patent or (b) Patent Right owned or controlled by such Milestone Obligor that claims priority to a Company Patent.

“Parent Group” shall mean Parent and all of its direct and indirect subsidiaries including the Acquired Company.

“Patent Rights” shall have the meaning set forth in part (a) of the definition of “Intellectual Property” in this Exhibit A.

“Permits” shall have the meaning set forth in Section 2.11(b) (Contingent Consideration).

“Permitted Encumbrances” shall mean: (a) statutory liens for current Taxes or other governmental charges (i) not yet due and payable or (ii) the amount or validity of which is being contested in good faith by appropriate proceedings by Seller or the Acquired Company and for which appropriate reserves have been established in accordance with the Accounting Principles; (b) mechanics’, carriers’, workers’, repairers’ and similar statutory liens arising or incurred in the ordinary course of business for amounts that are not delinquent and that are not, individually or in the aggregate, significant, unless being contested in good faith by appropriate proceedings and for which adequate accruals or reserves have been established; (c) Liens arising under conditional sales Contracts and equipment leases with third parties entered into in the ordinary course of business which do not, individually or in the aggregate, materially impair the continued ownership, use or operation of the assets to which they relate; (d) Liens, the existence of which would not, individually or in the aggregate, reasonably be expected to have a Company Material Adverse Effect; or (e) non-exclusive licenses or non-exclusive sublicenses granted to others in the ordinary course of the Business.

“Permitted Transfer” shall mean a transfer of the right to receive the Milestone Payments (a) on death by will or intestacy, (b) by instrument to an inter vivos or testamentary trust in which the Milestone Payments are to be passed to beneficiaries upon the death of the trustee, (c) pursuant to a court order, or (d) made by operation of law (including a consolidation or merger) or without consideration in connection with the dissolution, liquidation or termination of any corporation, limited liability company, partnership or other Entity.

“Person” shall mean any individual, Entity or Governmental Body.

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“Personal Data” has the meaning given to such term in the GDPR.

“Phase 2 Study” shall mean a clinical trial of a PRX004 Milestone Product conducted by or on behalf of a Milestone Obligor that would satisfy the requirements of 21 C.F.R. § 312.21(b), or its foreign equivalent and is conducted with the intent of submitting the resulting data to the FDA and EMA.

[***]

“Phase 3 Study” shall mean a clinical trial of a PRX004 Milestone Product conducted by or on behalf of a Milestone Obligor that would satisfy the requirements of 21 C.F.R. § 312.21(c), or its foreign equivalent and is conducted with the intent of submitting the resulting data to the FDA and EMA. For the avoidance of doubt, “Phase 3 Study” excludes any Phase 2b Study.

“PMDA” shall mean the Pharmaceuticals and Medical Devices Agency of Japan, and any successor agency thereto.

“Pre-Closing Period” shall have the meaning set forth in Section 4.1 (Access).

“Pre-Closing Tax Period” shall mean any taxable period (or portion thereof) ending on or before the occurrence of Closing on the Closing Date, and the portion of the Straddle Period up to the occurrence of Closing on the Closing Date.

“Pre-Closing Taxes” shall mean all Taxes imposed on the Acquired Company for Pre-Closing Tax Periods [***]; provided, however, that Pre-Closing Taxes shall not include (a) any Taxes resulting from any transactions occurring on the Closing Date after the Closing, (b) any Taxes resulting from any breach by Buyer of Section 5.4 (Tax Matters), or (c) any Transfer Taxes. In the case of any Straddle Period, the amount of any Taxes based on or measured by income, receipts or payroll of the Acquired Company for the Pre-Closing Tax Period shall be determined based on an interim closing of the books as of the occurrence of Closing on the Closing Date and the amount of any Pre-Closing Taxes for the Straddle Period shall be calculated by reference to any income, receipts or payroll of the Acquired Company on or prior to the interim closing of the books; provided, however, that Pre-Closing Taxes shall only include (i) Taxes assessed on the Acquired Company prior to 5:00 p.m. Dublin, Ireland time on the date that is four years from the end of the accounting period in which the Acquired Company’s Irish corporation Tax Return relating to the accounting period of the Acquired Company current at the Closing Date is due to be filed ; and (ii) [***].

“Pricing Approval” shall mean, in any country where a Governmental Body approves or determines pricing for, pharmaceutical products, receipt of such pricing approval or determination (as the case may be).

“PRX004 Milestone Product” shall mean any product candidate or product being developed or commercialized by or on behalf of any Milestone Obligor that contains or comprises a Compound.

“Purchase Price” shall mean the Closing Purchase Price and any consideration payable by Buyer pursuant to Section 1.7 (Contingent Consideration).

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“Reference Time” shall mean 12:01 a.m., Dublin, Ireland time, on the Closing Date.

“Registered IP” shall mean any and all Intellectual Property that is registered, filed, or issued under the authority of any Governmental Body, including all Patent Rights, registered copyrights, registered mask works, registered trademarks, and all applications for any of the foregoing.

“Regulatory Approval” shall mean any and all licenses, registrations, authorizations and approvals that are necessary for the marketing and sale of a pharmaceutical product in a given country or regulatory jurisdiction, but excluding, in each case, Pricing Approvals.

“Relevant VAT Periods” has the meaning set forth in Section 5.4(g) of this Agreement.

“Relief” shall mean any relief, allowance, exemption, set-off, deduction or credit of whatsoever nature in computing any profits for Tax purposes or any credit, relief or allowance in respect of Tax.

[***]

“Sale” shall have the meaning set forth in Section 1.1 (Purchase and Sale of Shares).

“Sales Report” shall have the meaning set forth in Section 1.7(e) (Contingent Consideration).

“Secondary Tax Liability” shall mean any Tax liability that arises (whether before, on or after Closing) to the Acquired Company, Buyer or any Affiliate of Buyer: (i) due to the relationship for Tax purposes before Closing of the Acquired Company with any person other than Buyer or an Affiliate of Buyer; or (ii) under a legally binding obligation (whether or not conditional) entered into by the Acquired Company on or before Closing otherwise than in the ordinary course of business.

“Seller Prepared Returns” shall have the meaning set forth in Section 5.4(a) (Tax Matters).

“Seller” shall have the meaning set forth in the preamble of this Agreement.

“Seller VAT Group” shall have the meaning set forth in Section 5.4(g) (Tax Matters).

“Shares” shall have the meaning set forth in the recitals of this Agreement.

“Specified Representations” shall mean the representations and warranties set forth in [***].

“Straddle Period” shall mean any taxable period beginning on or before and ending after the Closing Date.

“Subsidiary” shall mean, with respect to any Person, partnership, limited liability company, corporation or other business entity of which (a) if a corporation, a majority of the total voting power of shares of capital stock entitled (without regard to the occurrence of any

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contingency) to vote in the election of directors, managers, or trustees thereof is at the time owned or controlled, directly or indirectly, by that Person or one or more of the other Subsidiaries of that Person or a combination thereof, or (b) if a partnership, limited liability company or other business entity, a majority of the partnership or other similar ownership interests thereof is at the time owned or controlled, directly or indirectly, by that Person or one or more Subsidiaries of that Person or a combination thereof.

“Supplies” has the meaning set forth in Section 5.4(g) of this Agreement.

“Tax” or “Taxes” shall mean all federal, state or local and all foreign taxes including levies, impost, surcharge, contribution, income, gross receipts, windfall profits, value added, severance, property, production, sales, use, duty, license, excise, franchise, employment, withholding or similar taxes of any kind (including, for the avoidance of doubt, any pay related social insurance in Ireland and corresponding obligations elsewhere), and shall further include any amount payable as a consequence of any claim, direction, order or determination of any tax, revenue, fiscal, government or municipal or local authority or any other statutory governmental, state, provincial or local governmental authority, body, court, tribunal or official whatsoever (whether of Ireland or elsewhere in the world) competent to impose, administer, levy, assess or collect any of the foregoing together with any fines, interest, charges, surcharges, costs, additions or penalties with respect thereto and any interest with respect to such additions or penalties.

“Tax Certificate” shall have the meaning set forth in Section 5.4(i) (Tax Matters).

“Tax Claim” shall have the meaning set forth in Section 5.4(d) (Tax Matters).

“Tax Returns” shall mean any return, statement, report, tax filing or form (including estimated Tax returns and reports, withholding Tax returns and reports, any schedule or attachment, and information returns and reports), including any amendments, filed or required to be filed with a Governmental Body.

“TCA” shall mean the Taxes Consolidation Act 1997 of Ireland (as amended).

“Third-Party Claim” shall have the meaning set forth in Section 8.3 (Third-Party Claims).

“Transferee” shall have the meaning set forth in Section 1.7(f) (Contingent Consideration).

“Transaction Documents” means this Agreement and the Transition Services Agreement, in each case together with any schedules, exhibits, annexes and appendices thereto.

“Transfer Taxes” shall mean any sales, use, stock transfer, value added, real property transfer, real property gains, transfer, stamp, registration, documentary, recording or similar duties or taxes together with any interest thereon, penalties, fines, costs, fees, additions to tax or additional amounts with respect thereto incurred in connection with the transactions contemplated hereby.

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“Transition Services Agreement” shall mean the Transition Services Agreement substantially in the form attached hereto as Exhibit D to be entered into by and between Seller and Buyer on or prior to the Closing.

“Unaudited Balance Sheet” shall have the meaning set forth in Section 2.4 (Financial Statements).

“United States” or “U.S.” shall mean the United States of America and its territories and possessions.

“Update Report” shall have the meaning set forth in Section 1.7(d) (Contingent Consideration).

“Valid Claim” shall mean any claim contained in any (a) issued, unexpired Patent Right that has not been: (i) revoked or held unenforceable, unpatentable or invalid, in each case, by a final and unappealable (or if appealable, for which no appeal is properly filed within the time allowed to file an appeal) decision of a court or other Governmental Body of competent jurisdiction; or (ii) abandoned, disclaimed, denied or admitted to be invalid, unpatentable or unenforceable through reissue, re-examination, disclaimer or otherwise; or (b) pending application for any Patent Rights, provided that an application for Patent Rights pending for more than [***] after the date on which such application entered National Phase (or equivalent) in the relevant country or jurisdiction shall not be considered to have any Valid Claim for purposes of this Agreement unless and until a Patent Right with respect to such application issues with such claim.

“VAT” means value added tax or equivalent tax.

“VAT Regulations 2010” shall means the Value-Added Tax Regulations 2010 (S.I. 639 of 2010) of Ireland.

“VATCA” shall mean the Value-Added Tax Consolidation Act 2010 of Ireland (as amended).

“VAT Group Remitter” shall have the meaning set forth in Section 5.4(g) (Tax Matters).

“Voluntary Act” shall have the meaning set forth in Section 8.10 (Voluntary Acts).

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U.S. LICENSE AGREEMENT

by and among


PROTHENA BIOSCIENCES LIMITED


and


CELGENE SWITZERLAND LLC


Dated as of July 30, 2021

TABLE OF CONTENTS

Certain schedules and exhibits have been omitted pursuant to Item 601(b)(2) of Regulation S-K. The Company agrees to furnish supplementally a copy of any omitted schedules or exhibits.

LIST OF SCHEDULES

SCHEDULE 1.28 EXISTING PROGRAM AGREEMENTS

SCHEDULE 1.40 IN-LICENSE AGREEMENTS AND OTHER THIRD PARTY

AGREEMENTS

SCHEDULE 1.45 LICENSED PROGRAM ANTIBODIES

SCHEDULE 1.47(b) LICENSED PROGRAM PATENTS

SCHEDULE 1.49 LICENSED TARGET

SCHEDULE 1.64 PROTHENA LICENSED COLLABORATION PATENTS

SCHEDULE 1.66 PROTHENA PLATFORM TECHNOLOGY

SCHEDULE 8.2 EXCEPTIONS TO PROTHENA REPRESENTATIONS AND

WARRANTIES

SCHEDULE 8.4 EXCEPTIONS TO CELGENE REPRESENTATIONS AND

WARRANTIES

U.S. LICENSE AGREEMENT

This U.S. LICENSE AGREEMENT (this “Agreement”) is entered into and made effective as of July 30, 2021 (the “Effective Date”) by and between Prothena Biosciences Limited, an Irish limited company (“Prothena”) and Celgene Switzerland LLC, a Delaware limited liability company (“Celgene”). Celgene and Prothena are each referred to herein by name or as a “Party” or, collectively, as the “Parties”.

RECITALS

WHEREAS, Prothena and Celgene entered into that certain Master Collaboration Agreement, dated as of March 20, 2018 (the “Master Collaboration Agreement”), pursuant to which, among other things, Prothena has conducted research and development programs with respect to certain targets (each, a “Program”) and Celgene has an exclusive option to obtain an exclusive license to research, develop, manufacture and commercialize Antibodies that Target such targets;

WHEREAS, pursuant to the terms of the Master Collaboration Agreement, upon exercise by Celgene of its IND Option (as defined in the Master Collaboration Agreement) with respect to a given Program, the Parties are obligated to enter into a U.S. License Agreement with respect to such Program; and

WHEREAS, Celgene has exercised its IND Option (as defined in the Master Collaboration Agreement) with respect to the Licensed Program, and, as such, the Parties are entering into this Agreement pursuant to which, among other things, Prothena grants to Celgene exclusive rights and licenses with respect to the research, development, manufacture and commercialization of Licensed Antibodies and Licensed Products in the Territory, on the terms and subject to the conditions set forth herein.

ARTICLE 1
DEFINITIONS

Unless specifically set forth to the contrary herein, the following terms shall have the respective meanings set forth below. Capitalized terms used, but not defined, herein will have the meanings ascribed to them in the Master Collaboration Agreement.

1.1“Accounting Standards” means U.S. generally accepted accounting principles (“GAAP”) or, to the extent that Celgene adopts International Financial Reporting Standards (“IFRS”), then “Accounting Standards” shall mean IFRS, in either case consistently applied.

1.2“Affiliate” means any Person which, directly or indirectly through one or more intermediaries, controls, is controlled by or is under common control with another Person. For purposes of this definition, the term “control” (including, with correlative meanings, the terms “controlled by” and “under common control with”) as used with respect to a Person means (a)

direct or indirect ownership of fifty percent (50%) or more of the voting securities or other voting interest of any Person (including attribution from related parties), or (b) the possession, directly or indirectly, of the power to direct or cause the direction of the management and policies of such Person, whether through ownership of voting securities, by contract, as a general partner, as a manager, or otherwise.

1.3“Annual Net Sales” means, on a Licensed Product-by-Licensed Product basis, total Net Sales by Celgene, its Affiliates and Sublicensees in the Territory of such Licensed Product in a particular Calendar Year, calculated in accordance with Accounting Standards consistently applied.

1.4“Antibody” means any [***] antibody (including [***] whether human, humanized, chimeric, murine, synthetic or from any other source.

1.5“Applicable Law” or “Applicable Laws” means all applicable laws, statutes, rules, regulations, orders, judgments or ordinances having the effect of law of any national, multinational, federal, state, provincial, county, city or other political subdivision, including, to the extent applicable, GCP, GLP and GMP, as well as all applicable data protection and privacy laws, rules and regulations, including, to the extent applicable, the United States Department of Health and Human Services privacy rules under the Health Insurance Portability and Accountability Act (“HIPAA”) and the Health Information Technology for Economic and Clinical Health Act and the General Data Protection Regulation (2016/679).

1.6“Biomarker” means a parameter or characteristic in a patient or Patient Sample, the measurement of which is useful (a) for purposes of selecting appropriate therapies or patient populations or monitoring disease susceptibility, severity or state, or monitoring therapies for such patient and/or (b) for predicting the outcome of a particular treatment of such patient.

1.7“Biosimilar Application” means an application or submission filed with a Regulatory Authority for marketing authorization of a Biosimilar Product.

1.8“Biosimilar Product” means, with respect to a given Licensed Product, a biological product (a) that contains (i) an identical active ingredient(s) as the Licensed Antibody in such Licensed Product, or (ii) a “highly similar” active ingredient(s) to the Licensed Antibody in such Licensed Product, as the phrase “highly similar” is used in 42 U.S.C. § 262(i)(2), and subject to the factors set forth in FDA’s Guidance for Industry, “Quality Considerations in Demonstrating Biosimilarity to a Reference Protein Product,” (February 2012), at Section VI, or any successor FDA guidance thereto, (b) for which Regulatory Approval is obtained by referencing Regulatory Materials of such Licensed Product, (c) is approved for use in such country (or region) pursuant to a Regulatory Approval process governing approval of interchangeable or biosimilar biologics as described in 42 U.S.C. §§ 262, or a similar process for Regulatory Approval in any country (or region) outside the United States, or any other similar provision that comes into force, or is the subject of a notice with respect to such Licensed Product under 42 U.S.C. § 262(l)(2) or any other similar provision that comes into force in such country (or region), and (d) is sold in the same country as such Licensed Product by any Third Party that is not a Sublicensee of Celgene or its Affiliates with respect to the Prothena IP and did

[***] Certain information in this document has been excluded pursuant to Regulation S-K, Item 601(b)(10). Such excluded information is both not material and not material and the type of information that the registrant customarily and actually treats as private and confidential.

not purchase such product in a chain of distribution that included any of Celgene or any of its Affiliates or its Sublicensees.

1.9“BPCIA” means Biologics Price Competition and Innovation Act of 2009, as amended.

1.10“Business Day” means a day on which banking institutions in New York City, New York, are open for business, excluding any Saturday or Sunday.

1.11“Calendar Quarter” means the period beginning on the Effective Date and ending on the last day of the calendar quarter in which the Effective Date falls, and thereafter each successive period of three (3) consecutive calendar months ending on the last day of March, June, September, or December, respectively; provided that the final Calendar Quarter shall end on the last day of the Term.

1.12“Calendar Year” means the period beginning on the Effective Date and ending on December 31 of the calendar year in which the Effective Date falls, and thereafter each successive period of twelve (12) consecutive calendar months beginning on January 1 and ending on December 31; provided that the final Calendar Year shall end on the last day of the Term.

1.13“Celgene IP” means Patents and Know-How owned or otherwise controlled (through license or otherwise, but excluding through grant of a license from Prothena to Celgene pursuant to this Agreement) by Celgene or any of its Affiliates (including any Know-How that is, created, conceived, discovered, first generated, invented, first made or first reduced to practice by or on behalf of Celgene or any of its Affiliates pursuant to the conduct of activities under this Agreement). For the avoidance of doubt, Celgene IP excludes (i) Know-How that is created, conceived, discovered, first generated, invented, first made or first reduced to practice by or on behalf of Prothena, solely or jointly with a Third Party; (ii) Joint Program IP (as defined under the Master Collaboration Agreement); (iii) [***], and (iv) Joint IP.

1.14“Celgene Phase 1 Portion Participation Right” means the Celgene Phase 1 Portion Participation Right (as defined in the Master Collaboration Agreement) for the Licensed Program.

1.15“Change of Control” in respect of a Person (an “Acquired Person”) shall be deemed to have occurred upon any of the following occurring after the Effective Date: (i) any Person or group of Persons that is not an Affiliate of such Acquired Person becomes the beneficial owner (directly or indirectly) of more than fifty percent (50%) of the voting shares of such Acquired Person; (ii) such Acquired Person consolidates with or merges into or with another Person that is not an Affiliate of such Acquired Person pursuant to a transaction in which more than fifty percent (50%) of the voting shares of the acquiring or resulting entity outstanding immediately after such consolidation or merger is not held by the holders of the outstanding voting shares of such Acquired Person immediately preceding such consolidation or merger; and/or (iii) that Acquired Person sells or transfers to another Person that is not an Affiliate of such Acquired Person all or substantially all of its assets.

1.16“Clinical Trial” means a human clinical trial, including any Phase 1 Clinical Trial, Phase 2 Clinical Trial or Registration Enabling Clinical Trial, any study incorporating

more than one of these phases, or any human clinical trial commenced after Regulatory Approval.

1.17“Commercialization” means any and all activities directed to the commercialization of a product (which may include related diagnostic products, if applicable), including commercial manufacturing (including Manufacturing) and commercial supply of a product, marketing, detailing, promotion, market research, distributing, order processing, handling returns and recalls, booking sales, customer service, administering and commercially selling such product, importing, exporting and transporting such product for commercial sale, and seeking of pricing and reimbursement of a product (if applicable), whether before or after Regulatory Approval has been obtained (including making, having made, using, importing, selling and offering for sale such product (or related diagnostic product, if applicable)), as well all regulatory compliance with respect to the foregoing. For clarity, “Commercialization” does not include any Clinical Trial commenced after Regulatory Approval. When used as a verb, “Commercialize” means to engage in Commercialization.

1.18“Commercially Reasonable Efforts” means, with respect to Celgene in relation to an obligation under this Agreement with respect to a Licensed Antibody or Licensed Product, such efforts that are consistent with the efforts and resources normally used by Celgene in the exercise of its commercially reasonable business practices relating to performance of an obligation for a similar pharmaceutical compound or product (including the research, development, manufacture and commercialization of a pharmaceutical compound or product), as applicable, at a similar stage in its research, development or commercial life as the relevant Licensed Antibody or Licensed Product, and that has commercial and market potential similar to the relevant Licensed Antibody or Licensed Product, taking into account issues of intellectual property coverage, safety and efficacy, stage of development, product profile, competitiveness of the marketplace, proprietary position, regulatory exclusivity, anticipated or approved labeling, present and future market and commercial potential, the likelihood of receipt of Regulatory Approval, profitability (including pricing and reimbursement status achieved or likely to be achieved), amounts payable to licensors of patents or other intellectual property rights, [***], and legal issues.

1.19“Confidential Information” means, with respect to a Party, all confidential and proprietary information and materials, including Know-How, marketing plans, strategies, and customer lists, in each case, that are disclosed by or on behalf of such Party to the other Party pursuant to this Agreement, regardless of whether any of the foregoing are marked “confidential” or “proprietary” or communicated to the other Party by or on behalf of the disclosing Party in oral, written, visual, graphic or electronic form.

1.20“Control”, “Controls” or “Controlled” means, with respect to any intellectual property (including Know-How) or Confidential Information, the ability of a Party or its Affiliates, as applicable, (whether through ownership or license (other than a license granted in this Agreement)) to grant to the other Party the licenses or sublicenses as provided herein, or to otherwise disclose such intellectual property or Confidential Information to the other Party, without violating the terms of any then-existing agreement with any Third Party at the time such Party or its Affiliates, as applicable, would be required hereunder to grant the other Party such

license or sublicenses as provided herein or to otherwise disclose such intellectual property or Confidential Information to the other Party.

1.21“Cover”, “Covering” or “Covered” means, with reference to a Patent claim, that such Patent claim has a Valid Claim that claims the [***], and that the sale of a Licensed Antibody (or product incorporating such Licensed Antibody) would infringe such Valid Claim in the country in which such activity occurs without a license thereto (or ownership thereof); provided, that with respect to method of use, such method of use is for an Indication for which Regulatory Approval has been received (as set forth on the approved labeling for the applicable Licensed Product incorporating such Licensed Antibody) for such Licensed Antibody in such country.

1.22“Derivative” means, with respect to a Licensed Target [***] thereof.

1.23“Development” means (i) research activities (including drug discovery, identification and/or synthesis) with respect to a product (which may include related diagnostic products, if applicable), and/or (ii) preclinical and clinical drug development activities, and other development activities, with respect to a product (which may include related diagnostic products, if applicable), including test method development and stability testing, toxicology, formulation, process development, qualification and validation, manufacture scale-up, development-stage manufacturing (including Manufacturing), quality assurance/quality control, Clinical Trials (including Clinical Trials and other studies commenced after Regulatory Approval), statistical analysis and report writing, the preparation and submission of INDs and MAAs, regulatory affairs with respect to the foregoing and all other activities necessary or useful or otherwise requested or required by a Regulatory Authority or as a condition or in support of obtaining or maintaining a Regulatory Approval. When used as a verb, “Develop” means to engage in Development.

1.24“Diagnostic Product” means, on a Licensed Product-by-Licensed Product basis, any diagnostic product (which may include a Licensed Antibody or Licensed Product being used as a diagnostic product) which is necessary or reasonably useful (a) for the [***] in a patient or Patient Sample, and/or (b) to [***] in a patient or Patient Sample, and/or (c) to [***] to achieve improved safety or effectiveness, and/or (d) in disease identification, prognosis, disease monitoring, monitoring [***], in each case of (a), (b), (c) and (d), which is intended for use or is Developed or approved for use in connection with a therapeutic Licensed Antibody or Licensed Product (which may include [***]). Without limiting the foregoing, Diagnostic Products shall include “Companion Diagnostics” for a pharmaceutical product as defined in FDA’s “Guidance for Industry and Food and Drug Administration Staff - In Vitro Companion Diagnostic Devices” as well as complementary diagnostics.

1.25“Dollars” or “$” means the legal tender of the United States.

1.26“EU” means all countries that are officially recognized as member states of the European Union at any particular time.

1.27“Executive Officers” means in the case of Prothena, Prothena’s Chief Executive Officer and in the case of Celgene,, the Executive Vice President, Research and Early Development of Bristol-Myers Squibb Company, which is an Affiliate of Celgene, or the Chief

Medical Officer of Bristol-Myers Squibb Company (or the officer or employee of Bristol-Myers Squibb Company then serving in a substantially equivalent capacity) or, in each case with respect to any of the foregoing, his or her designee.

1.28“Existing Program Agreements” means any agreement between Prothena (or its Affiliates, as applicable) and any Third Party solely related to the Development or Manufacture of any Licensed Antibodies or Licensed Products, in effect as of the Effective Date, as set forth on Schedule 1.28.

1.29“Field” means any and all uses or purposes, including the treatment, prophylaxis, palliation, diagnosis or prevention of any human or animal disease, disorder or condition.

1.30“First Commercial Sale” means, on a Licensed Product-by-Licensed Product basis in the Territory, the first sale of such Licensed Product in the Territory for use or consumption by the general public (following receipt of all Regulatory Approvals that are required in order to sell such Licensed Product in the Territory) and for which any of Celgene or its Affiliates or Sublicensees has invoiced sales of Licensed Products in the Territory; provided, however, that the following shall not constitute a First Commercial Sale: (a) any sale to an Affiliate or Sublicensee, unless the Affiliate or Sublicensee is the last Person in the distribution chain of the Licensed Product; or (b) any use of such Licensed Product in Clinical Trials or non-clinical development activities with respect to such Licensed Product by or on behalf of a Party, or disposal or transfer of such Licensed Product for a bona fide charitable purpose, compassionate use or samples.

1.31“Global License Agreement” means each Global License Agreement entered into between the Parties (or their respective Affiliates, as applicable) pursuant to the Master Collaboration Agreement.

1.32“Good Clinical Practices” or “GCP” means the applicable then-current ethical and scientific quality standards for designing, conducting, recording, and reporting trials that involve the participation of human subjects as are required by applicable Regulatory Authorities or Applicable Law in the relevant jurisdiction, including in the United States, Good Clinical Practices established through FDA guidances, and, outside the United States, Guidelines for Good Clinical Practice – ICH Harmonized Tripartite Guideline (ICH E6).

1.33“Good Laboratory Practices” or “GLP” means the applicable then-current good laboratory practice standards as are required by applicable Regulatory Authorities or Applicable Law in the relevant jurisdiction, including in the United States, those promulgated or endorsed by the FDA in U.S. 21 C.F.R. Part 58, or the equivalent thereof as promulgated or endorsed by the applicable Regulatory Authorities outside of the United States.

1.34“Good Manufacturing Practices” or “GMP” means all applicable standards relating to manufacturing practices for fine chemicals, intermediates, bulk products and/or finished pharmaceutical products, as are required by applicable Regulatory Authorities or Applicable Law in the relevant jurisdiction, including, as applicable, (a) all applicable requirements detailed in the FDA’s current Good Manufacturing Practices regulations, U.S. 21 C.F.R. Parts 210 and 211, (b) all applicable requirements detailed in the EMA’s “The Rules Governing Medicinal Products in the European Community, Volume IV, Good Manufacturing

Practice for Medicinal Products”, and (c) all Applicable Laws promulgated by any Governmental Authority having jurisdiction over the manufacture of the applicable compound or pharmaceutical product, as applicable.

1.35“Governmental Authority” means any (a) federal, state, local, municipal, foreign or other government, (b) governmental or quasi-governmental authority of any nature (including any governmental division, subdivision, department, agency, bureau, branch, office, commission, council, board, instrumentality, officer, official, representative, organization, unit, body or entity and any court or other tribunal), (c) multinational governmental organization or body or (d) entity or body exercising, or entitled to exercise, any executive, legislative, judicial, administrative, regulatory, police, military or taxing authority or power of any nature.

1.36“IND” means an investigational new drug application (including any amendment or supplement thereto) submitted to the FDA pursuant to U.S. 21 C.F.R. Part 312, including any amendments thereto. References herein to IND shall include, to the extent applicable, any comparable filing(s) outside the U.S. for the investigation of any product in any other country or group of countries (such as a Clinical Trial Application in the EU).

1.37“IND Option Exercise Fee” shall mean the IND Option Exercise Fee (as defined in the Master Collaboration Agreement) for the Licensed Program.

1.38“Indication” means an entirely separate and distinct disease or medical condition in humans [***]. For clarity, [***].

1.39“Initiation” means, with respect to a given Clinical Trial, the administration of the first dose of Licensed Product to the first properly enrolled subject in such Clinical Trial in accordance with the protocol for such Clinical Trial.

1.40“In-License Agreements” means any agreement between Prothena (or its Affiliates, as applicable) and any Third Party pursuant to which such Third Party licenses to Prothena (or its Affiliates, as applicable) any Patents or Know-How included in the Prothena IP, including those set forth on Schedule 1.40.

1.41 “Know-How” means all proprietary (a) information, techniques, technology, practices, trade secrets, inventions, methods (including methods of use or administration or dosing), knowledge, data, results and software and algorithms, including pharmacological, toxicological and clinical test data and results, compositions of matter, chemical structures and formulations, sequences, processes, formulae, techniques, research data, reports, standard operating procedures, batch records, manufacturing data, analytical and quality control data, analytical methods (including applicable reference standards), assays and research tools, in each case, whether patentable or not; and (b) tangible manifestations thereof, including any and all of the foregoing relating to Licensed Program Biological and Chemical Materials.

1.42“Licensed Antibody” means (a) any Licensed Program Antibody and (b) any other Antibody that is a variant, fragment, derivative or other modification of a Licensed Program Antibody that (i) Targets the Licensed Target, (ii) is made by or on behalf of Celgene or its Affiliates or Sublicensees during the Term in the course of its activities performed under this Agreement and (iii) is claimed (or was claimed in an issued Patent that has subsequently expired)

as a composition of matter in a Licensed Program Patent set forth on Schedule 1.47(b), Prothena Licensed Collaboration Patent set forth on Schedule 1.64, or Joint Program Patent (as defined in the Master Collaboration Agreement) as applicable, or any substitutions, divisionals, continuations, continuations-in-part, reissues, renewals, registrations, confirmations, re-examinations, extensions, supplementary protection certificates and the like of any such Licensed Program Patents, Prothena Licensed Collaboration Patents or Joint Program Patents (as defined in the Master Collaboration Agreement).

1.43“Licensed Product” means any product that constitutes, incorporates, comprises or contains a Licensed Antibody, whether or not as the sole active ingredient, and in all forms, presentations, and formulations (including manner of delivery and dosage). For clarity, different forms, formulations, presentations or dosage strengths of a given Licensed Product that constitute, incorporate, comprise or contain the same Licensed Antibody shall be considered the same Licensed Product for purposes of this Agreement. Licensed Products shall include, in all cases, any Licensed Program Product.

1.44“Licensed Program” means the Development program undertaken by or on behalf of Prothena pursuant to the Master Collaboration Agreement with respect to the Licensed Target.

1.45“Licensed Program Antibody” means, with respect to the Licensed Program, (i) the Collaboration Candidates (as defined in the Master Collaboration Agreement) that Target the Licensed Target that were Developed under such Licensed Program pursuant to the Master Collaboration Agreement, including those as set forth on Schedule 1.45 and (ii) all Related Antibodies with respect to any Antibody described in the foregoing clause (i) provided that such Related Antibodies are claimed (or were claimed in an issued Patent that has subsequently expired) as a composition of matter in a Licensed Program Patent set forth on Schedule 1.47(b), a Prothena Licensed Collaboration Patent set forth on Schedule 1.64, or a Joint Program Patent (as defined in the Master Collaboration Agreement) as applicable, or any substitutions, divisionals, continuations, continuations-in-part, reissues, renewals, registrations, confirmations, re-examinations, extensions, supplementary protection certificates and the like of any such Licensed Program Patents or Prothena Licensed Collaboration Patents. For the avoidance of doubt, Licensed Program Antibodies are included within the definition of Licensed Antibody.

1.46“Licensed Program Biological and Chemical Materials” means, with respect to the Licensed Program, any and all compositions of matter, cells, cell lines, assays, animal models, imaging agents, Patient Samples, Biomarkers and any other physical, biological or chemical material, that are Controlled by Prothena or its Affiliates and [***] the Licensed Target or Licensed Program Antibodies (or the Development, Manufacture or Commercialization thereof), including physical embodiments of the Licensed Program Antibodies and any diagnostics related to such Licensed Program Antibodies, in each case, (i) created, conceived, discovered, first generated, invented, first made or first reduced to practice by or on behalf of Prothena or its Affiliates, whether solely or jointly with any Third Party, in such Licensed Program under the Master Collaboration Agreement or (ii) otherwise utilized by or on behalf of Prothena or its Affiliates in the Licensed Program under the Master Collaboration Agreement. To the extent the Licensed Program Biological and Chemical Materials were created, conceived, discovered, first generated, invented, first made or first reduced to practice under the Licensed

Program under the Master Collaboration Agreement, such Licensed Program Biological and Chemical Materials shall be “Licensed Program Know-How” hereunder, and to the extent the Licensed Program Biological and Chemical Materials were not created, conceived, discovered, first generated, invented, first made or first reduced to practice under the Licensed Program under the Master Collaboration Agreement, but were otherwise utilized in the development of the Licensed Program under the Master Collaboration Agreement, such Licensed Program Biological and Chemical Materials shall be “Prothena Licensed Collaboration Know-How” hereunder.

1.47“Licensed Program IP” means, collectively:

(a)“Licensed Program Know-How” which means any and all Know-How that was created, conceived, discovered, first generated, invented, first made or first reduced to practice, in each case (i) by or on behalf of [***], (ii) by or on behalf of [***], or (iii) by or on behalf of [***]. For the avoidance of doubt, Licensed Program Know-How (i) includes ‘Program Know-How’ (as defined in the Master Collaboration Agreement) related to the Licensed Program but (ii) expressly excludes any Know-How created, conceived, discovered, first generated, invented, first made or first reduced to practice in the course of activities performed under this Agreement and any Joint Program Know-How (as defined in the Master Collaboration Agreement); and

(b)“Licensed Program Patents” which means any Patents in the Territory Controlled by Prothena or its Affiliates that claim or cover any Licensed Program Know-How, including the Patents set forth on Schedule 1.47(b). For the avoidance of doubt, Licensed Program Patents, include ‘Program Patents’ (as defined in the Master Collaboration Agreement) related to the Licensed Program, but expressly exclude Joint Program Patents (as defined in the Master Collaboration Agreement).

1.48“Licensed Program Product” means, with respect to the Licensed Program, any product that constitutes, incorporates, comprises or contains a Licensed Program Antibody, whether or not as the sole active ingredient, and in all forms, presentations, and formulations (including manner of delivery and dosage). For clarity, different forms, formulations, presentations or dosage strengths of a given Licensed Program Product that constitutes, incorporates, comprises or contains the same Licensed Program Antibody shall be considered the same Licensed Program Product for purposes of this Agreement. For the avoidance of doubt, Licensed Program Products are included within the definition of Licensed Products.

1.49“Licensed Target” means the target set forth on Schedule 1.49, including Derivatives thereof.

1.50“Manufacture” means all activities related to the manufacturing of a product or diagnostic product or, in either case, any component or ingredient thereof, including test method development and stability testing, formulation, process development, manufacturing scale-up whether before or after Regulatory Approval, manufacturing any product or diagnostic product in bulk or finished form for Development or Commercialization (as applicable), including filling and finishing, packaging, labeling, shipping and holding, in-process and finished product testing, release of a product or diagnostic product or, in either case, any component or ingredient thereof,

quality assurance and quality control activities related to manufacturing and release of a product or diagnostic product, and regulatory activities related to any of the foregoing.

1.51“Marketing Authorization Application” or “MAA” means a Marketing Authorization Application, Biologics License Application or similar application, as applicable, and all amendments and supplements thereto, submitted to the FDA, or any equivalent filing in a country or regulatory jurisdiction other than the U.S. with the applicable Regulatory Authority, to obtain marketing approval for a pharmaceutical or diagnostic product, in a country or in a group of countries.

1.52“Net Sales” means, in respect of a given Licensed Product, the total [***] amounts [***] for all sales of such Licensed Product in the Territory for use in the Field by Celgene, its Affiliates or Sublicensees to Third Party customers (including to distributors), less the following deductions [***] so as to arrive at “net sales” under Accounting Standards as reported by Celgene, its Affiliates or Sublicensees, as applicable, in such Person’s financial statements:

[***].

There shall be no double counting in determining the foregoing deductions from gross amounts invoiced to calculate Net Sales. The calculations set forth in this definition of “Net Sales” shall be determined in accordance with Accounting Standards.

Sales or other transfers between Celgene and its Affiliates or Sublicensees, as well as any transfers or dispositions of any Licensed Products for [***], in each case, shall be excluded from the computation of Net Sales.

The calculations set forth in this section shall be determined in accordance with Accounting Standards. If any Licensed Product is, or is sold as part of, a Combination Product, Net Sales shall be calculated assuming that the gross sale price of each unit is equal to the product of (i) Net Sales of the Combination Product calculated as above (i.e., calculated as for a non-Combination Product), and (ii) the fraction [***], where:

[***]

For purposes of this definition, “Combination Product” means any pharmaceutical product that (a) contains two or more active ingredients, including both (1) a Licensed Antibody and (2) one or more other compounds (which may be Antibodies) but that are not a Licensed Antibody, either as a fixed dose product, co-formulated product or co-packaged product, and sold for a single price, and (b) is Developed or Commercialized, alone or together with a Third Party, by Celgene or any of its Affiliates or Sublicensees. Any vehicles, adjuvants and excipients used in conjunction with any Licensed Antibody shall not be treated as active ingredients for the purposes of this definition.

1.53“Patents” means (a) all patents and patent applications in any country or supranational jurisdiction worldwide, (b) any substitutions, divisionals, continuations, continuations-in-part, reissues, renewals, registrations, confirmations, re-examinations,

extensions, supplementary protection certificates and the like of any such patents or patent applications, and (c) foreign counterparts of any of the foregoing.

1.54“Patient Sample” means tissue, fluid, or cells collected from a patient, or components of the foregoing.

1.55“Person” means any individual, partnership, joint venture, limited liability company, corporation, firm, trust, association, unincorporated organization, governmental authority or agency, or any other entity not specifically listed herein.

1.56“Phase 1 Clinical Trial” means a human clinical trial of a product that would satisfy the requirements of U.S. 21 C.F.R. Part 312.21(a) (as amended), or a similar clinical study prescribed by the Regulatory Authorities in a foreign country, and is intended to (a) determine the safety, pharmacokinetics and pharmacodynamic parameters in healthy individuals or patients, and (b) following the foregoing clause (a), further evaluate safety and pharmacokinetics (including exploration of trends of a biomarker-based or clinical endpoint-based efficacy relationship to dose which need not be designed to be statistically significant) of the product, whether or not in combination with concomitant treatment and which provides sufficient evidence of safety to be included in filings for a Phase 2 Clinical Trial or a Registration Enabling Clinical Trial with Regulatory Authorities.

1.57“Phase 1 Option” shall mean the Phase 1 Option (as defined in the Master Collaboration Agreement) for the Licensed Program.

1.58“Phase 1 Option Term” shall mean the Phase 1 Option Term (as defined in the Master Collaboration Agreement) for the Licensed Program.

1.59“Phase 2 Clinical Trial” means a human clinical trial of a product that would satisfy the requirements of U.S. 21 C.F.R. Part 312.21(b), as amended, and is intended to explore a variety of doses, dose response, and duration of effect, and to generate evidence of clinical safety and effectiveness for a particular Indication or Indications in a target patient population, or a similar clinical study prescribed by the relevant Regulatory Authorities in a country other than the United States.

1.60“Prosecution and Maintenance” or “Prosecute and Maintain” means, with regard to a Patent, the preparation, filing, prosecution and maintenance of such Patent, as well as re-examinations, reissues, appeals, and requests for patent term adjustments and patent term extensions with respect to such Patent, together with the initiation or defense of interferences, oppositions, inter partes review, derivations, re-examinations, post-grant proceedings and other similar proceedings (or other defense proceedings with respect to such Patent, but excluding the defense of challenges to such Patent as a counterclaim in an infringement proceeding) with respect to the particular Patent, and any appeals therefrom. For clarification, “Prosecution and Maintenance” or “Prosecute and Maintain” shall not include any other enforcement actions taken with respect to a Patent.

1.61“Prothena IP” means the Prothena Licensed Collaboration Patents, the Prothena Licensed Collaboration Know-How, the Licensed Program Patents and the Licensed Program

Know-How, as well as Prothena’s (and its Affiliates’) right, title and interest in and to the Joint IP and any Joint Program IP (as defined under the Master Collaboration Agreement).

1.62“Prothena Licensed Collaboration IP” means all Prothena Licensed Collaboration Know-How and Prothena Licensed Collaboration Patents

1.63“Prothena Licensed Collaboration Know-How” means any and all Know-How that is Controlled by Prothena or its Affiliates on or after the Effective Date that (a) is necessary [***] to research, develop, make, have made, import, use, offer to sell, sell or otherwise exploit any [***], Licensed Program Antibody or Licensed Program Product or (b) is or was otherwise introduced into or used in the performance of a Program by or on behalf of Prothena or its Affiliates, including (i) any diagnostics related to any such Licensed Program Antibody or Licensed Program Product and (ii) Know-How conceived, created discovered, first generated, invented, first made or first reduced to practice by or on behalf of a Prothena or its Affiliates, whether solely or jointly with any Third Party, in the course of activities performed under this Agreement; but expressly excluding Joint Know-How, Joint Program Know-How (as defined in the Master Collaboration Agreement) and Licensed Program Know-How.

1.64“Prothena Licensed Collaboration Patents” means any and all Patents in the Territory that are Controlled by Prothena or its Affiliates on or after the Effective Date that claim or cover (a) any Licensed Target, any Licensed Program Antibody or any Licensed Program Product, or the research, development, making, having made, import, use, offering to sell, selling or other exploitation of any of the foregoing, or (b) any Prothena Licensed Collaboration Know-How; but expressly excluding Joint Patents, Joint Program Patents (as defined in the Master Collaboration Agreement) and Licensed Program Patents. Prothena Licensed Collaboration Patents shall include the Patents set forth on Schedule 1.64.

1.65“Prothena Platform Patent” means a Patent within the Prothena Licensed Collaboration Patents that [***] claims the Prothena Platform Technology.

1.66“Prothena Platform Technology” means the [***]; but in any case excluding [***].

1.67“Registration Enabling Clinical Trial” means (a) a human clinical trial of a product that would satisfy the requirements of U.S. 21 C.F.R. Part 312.21(c), as amended, and is intended to (i) establish that the product is safe and efficacious for its intended use, (ii) define contraindications, warnings, precautions and adverse reactions that are associated with the product in the dosage range to be prescribed, and (iii) support Regulatory Approval for such product, or (b) a similar clinical study prescribed by the relevant Regulatory Authorities in a country other than the United States.

1.68“Regulatory Approval” means all approvals, licenses and authorizations of the applicable Regulatory Authority necessary for the marketing and sale of a pharmaceutical or diagnostic product for a particular Indication in a country or region (including separate pricing or reimbursement approvals, as necessary), and including the approvals by the applicable Regulatory Authority of any expansion or modification of the label for such Indication.

1.69“Regulatory Authority” means any national or supranational Governmental Authority, including the U.S. Food and Drug Administration (and any successor entity thereto) (the “FDA”) in the U.S., the European Medicines Agency (and any successor entity thereto) (the “EMA”) in the EU and the Ministry of Health, Labour and Welfare of Japan, or the Pharmaceuticals and Medical Devices Agency of Japan (or any successor to either of them) as the case may be (the “MHLW”) in Japan, or any health regulatory authority in any country or region that is a counterpart to the foregoing agencies, in each case, that holds responsibility for development and commercialization of, and the granting of Regulatory Approval for, a pharmaceutical or diagnostic product, as applicable, in such country or region.

1.70“Regulatory-Based Exclusivity” means, on a Licensed Product-by-Licensed Product basis in the Territory, that Celgene or any of its Affiliates or Sublicensees has been granted the exclusive legal right by a Regulatory Authority in the Territory to market and sell the Licensed Product in the Territory, in each case, such that market exclusivity is maintained for Celgene (or its Affiliate or Sublicensee, as applicable) in the Territory with respect to such Licensed Product as a result of such grant by such Regulatory Authority.

1.71“Regulatory Materials” means the regulatory registrations, applications, authorizations and approvals (including approvals of MAAs, supplements and amendments, pre- and post-approvals, pricing and reimbursement approvals, and labeling approvals), Regulatory Approvals and other submissions made to or with any Regulatory Authority for research, development (including the conduct of Clinical Trials), manufacture, or commercialization of a pharmaceutical or diagnostic product in a regulatory jurisdiction, together with all related correspondence to or from any Regulatory Authority and all documents referenced in the complete regulatory chronology for each MAA, including all Drug Master Files (if any), INDs and supplemental biologics license applications (sBLAs) and foreign equivalents of any of the foregoing.

1.72“Related Antibody” means, with respect to a given Antibody, any [***].

1.73“Royalty Term” means, on a Licensed Product-by-Licensed Product basis in the Territory, the period of time commencing on the First Commercial Sale of such Licensed Product in the Territory and expiring upon the latest of (a) the first date on which there is no Valid Claim of a Patent within the [***] Licensed Product in the Territory and (b) the [***] anniversary of the date of First Commercial Sale of such Licensed Product in the Territory.

1.74“Safety Reason” means [***].

1.75“Select Indication” means each of the following separate and distinct Indications: [***] such other Indications as the Parties may mutually agree in writing to be expressly included as a “Select Indication” for purposes of this Agreement; provided that such indication is identified as an approved use for the applicable Licensed Product in the approved label for such Licensed Product in the applicable country.

1.76“Sublicensee” means, with respect to Celgene, a Third Party to whom Celgene has granted a sublicense, either directly or indirectly, under the Prothena IP licensed to Celgene by Prothena pursuant to this Agreement, to Develop, Manufacture and/or Commercialize

Licensed Antibodies and Licensed Products in the Field in the Territory, but excluding any Third Party acting as a distributor and excluding Prothena and its Affiliates.

1.77“Target” means, with respect to a given Antibody and the Licensed Target, that such Antibody [***]. For the purposes of the “Target” definition, [***] means [***].

1.78“Territory” means the United States.

1.79“Third Party” means any Person other than Prothena or Celgene that is not an Affiliate of Prothena or of Celgene.

1.80“Third Party Claim” means any and all suits, claims, actions, proceedings or demands brought by a Third Party.

1.81“Third Party Damages” means all losses, costs, claims, damages, judgments, liabilities and expenses payable to a Third Party by a Party (or the Prothena Indemnitees or Celgene Indemnitees, as applicable) under a Third Party Claim (including reasonable attorneys’ fees and other reasonable out-of-pocket costs of litigation in connection therewith).

1.82“United States” or “U.S.” means the United States of America and all of its territories and possessions.

1.83“U.S. License Agreement” shall mean each U.S. License Agreement entered into between the Parties (or their respective Affiliates, as applicable) pursuant to the Master Collaboration Agreement. When used in this Agreement, references to U.S. License Agreements are references to U.S. License Agreements other than this Agreement.

1.84“Valid Claim” means a claim of a Patent within the Licensed Program Patents, Prothena Licensed Collaboration Patents, or Joint Program Patents (as defined in the Master Collaboration Agreement) in the Territory that has issued and has not expired, lapsed, been cancelled or abandoned, or been dedicated to the public, disclaimed, or held unenforceable, invalid, revoked or cancelled by a court or administrative agency of competent jurisdiction in an order or decision from which no appeal has been or can be taken, including through opposition, reexamination, reissue, disclaimer, inter partes review, post grant procedures or similar proceedings.

1.85Additional Definitions. Each of the following terms has the meaning described in the corresponding section of this Agreement indicated below:


Definition:			Section:
Acquired Person			1.15
Active Immunotherapeutic Approaches			4.2.1
Agreement			Preamble
Celgene			Preamble
Celgene Acquired Competing Antibody			4.4.2
Celgene Exclusivity Term			4.4.1
Celgene Indemnitees			9.2


Celgene Proposed Terms			4.2.2
Celgene Share			6.8.2(d)
Celgene Third Party Payments			5.2.4
Clinical Trial Preliminary Activities Outside Date			10.5
Combination Product			1.52
Competing Antibody			4.4.1
Competing Compound			4.1
Cure Period			10.2.1
Disclosing Party			7.1
Dispute			11.8.2
Electronic Delivery			11.12
Effective Date			Preamble
EMA			1.69
Excluded Claim			11.8.3(d)
FDA			1.69
Financial Transparency Laws			11.17
[***]			[***]
Force Majeure			11.3
GAAP			1.1
Grant			4.2.2
Grant Notice			4.2.2
HIPAA			1.5
IFRS			1.1
Indemnitee			9.3
Indemnitor			9.3
Indirect Taxes			5.5.2(b)
Insolvency Event			10.4
Joint IP			6.6.4
Joint Know-How			6.6.4
Joint Patents			6.6.4
Licensed Program Assets			2.5
Licensed Program Confidential Information			7.11
Licensed Program Know-How			1.47(a)
Licensed Program Non-Specific IP			7.2
Licensed Program Patents			1.47(b)
Licensed Program Specific IP			7.2
Master Collaboration Agreement			Recitals
MHLW			1.69
Negotiation Period			4.2.2
[***]			[***]
Notice Period			4.2.2


Ongoing Prothena Development Activities			2.3.3
Party or Parties			Preamble
Patent Liaison			6.7
Payee Party			5.5.2(b)
Paying Party			5.5.2(b)
Per Licensed Product Annual Net Sales			5.2.1
Program			Recitals
Prothena			Preamble
Prothena Indemnitees			9.1
Prothena Licensor			8.3.3
Prothena Ongoing Program Activities			2.3
Prothena Reversion Antibodies			10.10.1
Publishing Party			7.8.1
Receiving Party			7.1
Regulatory Milestone Payment			5.3.1
Right of First Negotiation			4.2.2
Sales Milestone Payment			5.4.1
SEC			7.4.1(a)
Securities Regulators			7.6
Tax Benefit			5.5.2(c)
Term			10.1.1
Transfer Date			2.2.1(a)

ARTICLE 2
DEVELOPMENT, MANUFACTURE AND COMMERCIALIZATION

2.1Development, Manufacturing and Commercialization.

2.1.1General. From and after the Effective Date, and subject to the terms and conditions of this Agreement (including Sections 2.2, 2.3, and 2.8), (i) Celgene will have the sole right (and shall solely control, at its discretion), itself and/or with or through its Affiliates, Sublicensees or other Third Parties, to Develop, Manufacture and Commercialize Licensed Antibodies and Licensed Products in the Field in the Territory, and (ii) Prothena and its Affiliates shall not have any right to, and shall not, conduct any Development, Manufacture or Commercialization of any Licensed Antibodies or Licensed Products in the Field in the Territory.

2.1.2Diligence. From and after the end of the Phase 1 Option Term, and subject to the terms and conditions of this Agreement (including Sections 2.2, 2.3, and 2.8), Celgene, itself and/or with or through its Affiliates, Sublicensees or other Third Parties, will use Commercially Reasonable Efforts to [***].

2.1.3Celgene Progress Updates. During the Term until such time as Celgene has submitted a MAA for at least one Licensed Product in a Select Indication in the Territory, Celgene and Prothena shall meet at least [***] to discuss the progress of Celgene’s material Development and Commercialization activities with respect to Licensed Products pursuant to this Agreement. Such meeting shall be either in person or telephonically as agreed to by the Parties. In addition, during the Term until such time as Celgene has submitted an MAA for at least one Licensed Product for a Select Indication in the Territory, at least [***] (or more frequently as agreed to by the Parties), Celgene shall submit to Prothena a written report summarizing the progress of Celgene’s material Development and Commercialization activities with respect to Licensed Products pursuant to this Agreement since the last report.

2.2Regulatory.

2.2.1Regulatory Materials.

(a)Subject to Section 2.3, and subject further to Section 2.6.1(b) of the Master Collaboration Agreement with respect to the Licensed Program, until the end of the Phase 1 Option Term for the Licensed Program (the “Transfer Date”), Prothena shall have the right, in consultation with Celgene, to prepare, file and maintain all Regulatory Materials (including any Regulatory Approvals) necessary for the Development and Manufacture of any Licensed Program Antibodies and/or Licensed Program Products in the Territory hereunder, and to interact with Regulatory Authorities in connection with the Development and Manufacture of any Licensed Program Antibodies and/or Licensed Program Products in the Territory hereunder. Prothena will provide Celgene with a reasonable opportunity to comment substantively on all material Regulatory Materials prior to filing or taking material action, and will reasonably and in good faith consider any comments and actions recommended by Celgene, including with respect to filing strategy. In addition, Prothena will allow Celgene or its representative to attend any and all meetings with Regulatory Authorities to the extent such attendance is not prohibited or limited by such Regulatory Authority.

(b)Subject to Section 2.3, after the Transfer Date, Celgene shall have the right, in consultation with Prothena, to prepare, file and maintain all Regulatory Materials (including any Regulatory Approvals) necessary for the Development, Manufacture and Commercialization of any Licensed Program Antibodies and/or Licensed Program Products in the Territory hereunder, and to interact with Regulatory Authorities in connection with the Development, Manufacture and Commercialization of any Licensed Program Antibodies and/or Licensed Program Products in the Territory hereunder. Celgene will provide Prothena with a reasonable opportunity to comment substantively on all material Regulatory Materials, but only if such Regulatory Materials directly impact regulatory matters with respect to Licensed Program Antibodies and/or Licensed Program Products outside the Territory, prior to filing or taking material action, and will reasonably and in good faith consider any comments and actions recommended by Prothena, including with respect to filing strategy. In addition, Celgene will allow Prothena or its representative to attend any and all meetings with Regulatory Authorities with respect to Licensed Program Antibodies and/or Licensed Program Products in the Territory to the extent such attendance is not prohibited or limited by such Regulatory Authority, but only if such meeting directly impacts regulatory matters with respect to Licensed Program Antibodies and/or Licensed Program Products outside the Territory.

2.2.2Safety Information. Prior to the Transfer Date, Prothena shall have the right to report all safety information to Regulatory Authorities with respect to the Licensed Program Antibodies and/or Licensed Program Products in the Territory hereunder, and shall promptly provide Celgene with all information concerning the pharmaceutical safety of Licensed Program Antibodies and/or Licensed Program Products in the Territory. After the Transfer Date, Celgene shall have the right to report all safety information to Regulatory Authorities with respect to the Licensed Program Antibodies and/or Licensed Program Products in the Territory hereunder, and shall promptly provide Prothena with all such information concerning the pharmaceutical safety of Licensed Program Antibodies and/or Licensed Program Products in the Territory.

2.2.3Step-In Right of Celgene. In the event that Prothena does not undertake any activities allocated to Prothena in the provisions of Section 2.2.1 or 2.2.2 in any respect, then, upon written notice from Celgene to Prothena, Celgene (or its designee) shall have the right to do so, and Prothena shall provide Celgene with reasonable assistance in connection therewith.

2.2.4Right of Reference; Access to Data. Celgene (and its designees) shall have, and Prothena (on behalf of itself and its Affiliates) hereby grants to Celgene (and its designees), access and a right of reference (without any further action required on the part of Prothena or its Affiliates, whose authorization to file this consent with any Regulatory Authority is hereby granted) to all Regulatory Materials with respect to the Licensed Program Antibodies and/or Licensed Program Products in the Territory that are Controlled by Prothena (or its Affiliates) and all data contained or referenced in any such Regulatory Materials for Celgene (and its designees) solely to the extent necessary for Celgene to exercise its rights and perform its obligations hereunder.

2.2.5Additional Regulatory Activities by Celgene. For the avoidance of doubt, without limiting any other rights or remedies of Celgene, Celgene shall have the right to undertake any regulatory activities, including to prepare, file and maintain all Regulatory Materials (including any Regulatory Approvals) necessary for the Development, Manufacture and Commercialization of any Licensed Antibodies and/or Licensed Products in the Territory hereunder, and to interact with Regulatory Authorities in connection with the Development, Manufacture and Commercialization of any Licensed Antibodies and/or Licensed Products in the Territory hereunder, to the extent such activities are not performed by Prothena.

2.2.6Pharmacovigilance. At the written request of Celgene, within [***] after such request, Prothena and Celgene (or its designee(s)) will enter into a pharmacovigilance agreement in order to, among other things, coordinate safety matters and share safety information with respect to Licensed Products.

2.3Prothena Ongoing Activities in Support of Licensed Program.

2.3.1Prothena Ongoing Program Activities. Notwithstanding the provisions of Section 2.1.1 or Section 2.2.1, Prothena shall have the right to continue to conduct Development activities (and related activities, including as set forth in Section 2.5.1(b)(iv) of the Master Collaboration Agreement with respect to the Licensed Program) for the Licensed Program under, and in accordance with, the Master Collaboration Agreement, through the first to occur of (i) the

end of the Phase 1 Option Term for the Licensed Program, or (ii) Celgene’s exercise of the Celgene Phase 1 Portion Participation Right; provided, however, that if thereafter, in the event that Prothena desires to conduct any Development activities (or related activities) in the Territory that are not set forth in the Master Collaboration Agreement or this Agreement, Prothena may only conduct such activities to the extent requested by Celgene in writing, or otherwise with the prior written consent of Celgene.

2.3.2Transition Supply. If Prothena was supplying (or having supplied) any Licensed Antibody and/or Licensed Product for any Clinical Trial(s) or other Development activities conducted with respect to the Licensed Program under the Master Collaboration Agreement, then, at Celgene’s written request, Prothena will be responsible for supplying, and shall supply, to Celgene (or its designee) Licensed Antibody(ies) and/or Licensed Product(s), for use in Development by or on behalf of Celgene hereunder for a period not to exceed [***] (or such longer period of time as agreed to by the Parties), as and to the extent requested by Celgene; provided that Celgene shall pay to Prothena a reasonable, fair value cost for such supply, which cost shall be negotiated in good faith and agreed to by the Parties prior to such supply. In such case, at the request of Celgene, the Parties shall negotiate in good faith and enter into an appropriate supply agreement (including a quality agreement) for Prothena to supply (or have supplied) Licensed Antibody and/or Licensed Product, as applicable, to Celgene (or its designee). Notwithstanding the foregoing, if Prothena has engaged a Third Party contract manufacturer for the supply of Licensed Antibodies and/or Licensed Products, and the agreement with such Third Party prohibits the supply to Celgene in accordance with the foregoing (provided that Prothena used good faith efforts not to include such prohibition during negotiations), then in lieu of the foregoing supply obligation, Prothena shall take such actions as reasonably requested by Celgene to facilitate the negotiations between Celgene and Prothena’s Third Party contract manufacturer of an appropriate supply agreement (including a quality agreement) for the supply of Licensed Antibody and/or Licensed Product, as applicable, to Celgene (or its designee).

2.3.3Other Continuing Development Activities. Without limiting the other obligations of Prothena hereunder (including as set forth in this Section 2.3), in the event that the Parties mutually agree in writing that Prothena or its Affiliates will conduct any other specific Development activities for Celgene after the Effective Date with respect to the Licensed Program (in addition to those set forth in the foregoing provisions of this Section 2.3) (the “Ongoing Prothena Development Activities”), then, in such case, the Parties shall negotiate in good faith and enter into a separate services agreement pursuant to which Prothena (or its Affiliates, as applicable) shall perform such Ongoing Prothena Development Activities.

Prothena’s obligations as set forth in the foregoing clauses 2.3.1 through 2.3.3, as applicable, are the “Prothena Ongoing Program Activities”.

2.4Assistance; Technology Transfer. Prothena shall (and shall cause its Affiliates to) cooperate with Celgene (and its designees) and provide reasonable assistance to Celgene (and its designees) to enable Celgene (and its designees) to Develop, Manufacture and Commercialize Licensed Antibodies and Licensed Products, as and to the extent requested reasonably by Celgene, including (i) conducting a technology transfer to Celgene with respect to the Licensed Program Know-How and Prothena Licensed Collaboration Know-How, (ii) providing Celgene (and its designees) reasonable assistance with respect to regulatory and Manufacturing transition

matters related to Licensed Antibodies and Licensed Products and (iii) providing Celgene (and its designees) with reasonable access by teleconference or in-person (as requested by Celgene) to Prothena personnel (and personnel of its Affiliates and Third Party contractors) involved in the Development or Manufacture of Licensed Antibodies and Licensed Products to assist with the transition and answer questions related to Licensed Antibodies, Licensed Products and Diagnostic Products.

2.5Covenant. Except as otherwise expressly permitted under this Agreement, commencing on the Effective Date until the end of the Term, Prothena shall not and shall cause its Affiliates not to (a) assign, transfer, convey, encumber (through a lien, charge, security interest, mortgage or similar encumbrance) or dispose of, or enter into any agreement with any Third Party to assign, transfer, convey, encumber (through a lien, charge, security interest, mortgage or similar encumbrance) or dispose of, any [***] (collectively, the “Licensed Program Assets”), except to the extent such assignment, transfer, conveyance, encumbrance or disposition would not conflict with, be inconsistent with or adversely affect in any respect any of the rights or licenses granted to Celgene hereunder, (b) license or grant to any Third Party, or agree to license or grant to any Third Party, any rights to any Licensed Program Assets if such license or grant could conflict with, be inconsistent with or adversely affect in any respect any of the rights or licenses granted to Celgene hereunder, or (c) [***] the Licensed Program Assets to any Third Party if such [***] could impair or conflict in any respect with any of the rights or licenses granted to Celgene hereunder.

2.6Other Antibodies and Products Developed by Celgene. Notwithstanding anything to the contrary contained herein, if Celgene (or any of its Affiliates), alone or with any Third Party, determines to Develop, Manufacture or Commercialize any Antibodies (or any product containing an Antibody), other than Licensed Antibodies or Licensed Products, then Celgene may do so in its sole discretion, without any obligations to Prothena with respect thereto, and Prothena shall have no rights in connection therewith, provided that Celgene’s or its Affiliates’ conduct of any such activities shall not modify or obviate Celgene’s obligations under this Agreement.

2.7Non-Exercise of Phase 1 Option for Licensed Program. In the event that Celgene does not exercise its Phase 1 Option for the Licensed Program in accordance with the Master Collaboration Agreement prior to the end of the Phase 1 Option Term for the Licensed Program, and Prothena desires (itself or with or through a Third Party) to continue the Development of the Licensed Program Antibodies and Licensed Program Products in the Field in the Territory, then at the written request of Prothena, Celgene shall discuss in good faith the terms under which Celgene may be willing to grant rights to Prothena under the Prothena IP for Prothena (itself or with or through a Third Party) to continue the Development of the Licensed Program Products in the Field in the Territory (including the Manufacture of Licensed Program Antibodies and Licensed Program Products in connection therewith), and to thereafter Commercialize Licensed Program Antibodies and Licensed Program Products in the Field in the Territory; provided that, for the avoidance of doubt, the provisions of Article 5 (other than Section 5.7) shall not apply with respect to any such activities.

2.8No Global License Agreement. For the avoidance of doubt, in the event that Celgene does not exercise its Phase 1 Option for the Licensed Program for the Licensed

Program, this Agreement shall remain in full force and effect unless and until this Agreement expires or is otherwise terminated in accordance with the terms hereof.

ARTICLE 3
ANTITRUST AND COMPETITION LAW COMPLIANCE

3.1Antitrust Compliance. For the avoidance of doubt, the Parties shall continue to comply with Section 3.2 of the Master Collaboration Agreement, and such provisions shall apply to this Agreement as if set forth directly herein, mutatis mutandis.

ARTICLE 4
EXCLUSIVITY

4.1Prothena Exclusivity. During the Term, Prothena shall not and shall ensure that its Affiliates shall not, anywhere in the world: (i) alone or with or through any Third Party, research [***], Develop, Manufacture or Commercialize (a) the Licensed Target or any Competing Compound, or (b) any diagnostic product intended for use, or Developed or approved for use with, the Licensed Target (including any diagnostic product intended for use, or Developed or approved for use with, any Competing Compound), in each case, other than Prothena’s performance of the Prothena Ongoing Program Activities (including engaging its Affiliates or Third Party subcontractors to perform the Prothena Ongoing Program Activities in accordance with this Agreement) as specifically set forth in Section 2.3; (ii) grant a license, sublicense or other rights to any Third Party to conduct any of the activities in the foregoing clause (i), other than Prothena’s performance of the Prothena Ongoing Program Activities (including engaging its Affiliates or Third Party subcontractors to perform the Prothena Ongoing Program Activities in accordance with this Agreement) as specifically set forth in Section 2.3; or (iii) transfer, assign, convey or otherwise sell any Competing Compound or any diagnostic product intended for use, or Developed or approved for use with, the Licensed Target (including any diagnostic product intended for use, or Developed or approved for use with, any Competing Compound). As used herein, the term “Competing Compound” means [***].

4.2Prothena Exception for Active Immunotherapeutic Approaches.

4.2.1Exception for Active Immunotherapeutic Approaches. Notwithstanding the provisions of Section 4.1, but subject to the provisions of Section 4.2.2, Prothena and its Affiliates (themselves, but not with or through any Third Parties) may conduct research, development, manufacture and commercialization of Active Immunotherapeutic Approaches outside of this Agreement; provided that no Licensed Antibodies or Licensed Products are utilized in the conduct of any such activities (including no use of a Licensed Antibody or Licensed Product for an Active Immunotherapeutic Approach). As used herein, “Active Immunotherapeutic Approaches”[***].

4.2.2Celgene Right of First Negotiation. During the Term, in the event that Prothena or its Affiliates intends to, directly or indirectly, sublicense, assign, transfer, convey or grant other rights, however structured, to a Third Party with respect to any Active Immunotherapeutic Approaches (including any rights with respect to the Development or Commercialization of any Active Immunotherapeutic Approaches (each, a “Grant”), Prothena will promptly notify Celgene in writing (and in all cases prior to the consummation of any

transaction or entering into any agreement in connection therewith) (a “Grant Notice”). Celgene will have a right of first negotiation with respect to the rights under the Grant (a “Right of First Negotiation”). If Celgene desires to exercise such Right of First Negotiation, Celgene will notify Prothena thereof in writing within [***] after receipt of the applicable Grant Notice (the “Notice Period”, which notice from Celgene [***]. If Celgene exercises such Right of First Negotiation within the Notice Period in accordance with this Section 4.2.2, the Parties will negotiate in good faith the terms of a definitive agreement pursuant to which Celgene would obtain rights that are the subject of the Grant [***] (the “Negotiation Period”). Until expiration of the Notice Period [***], or the expiration of the Negotiation Period [***], as applicable, Prothena (or its Affiliates, as applicable) shall not discuss or negotiate with any Third Party any transaction with respect to the Grant. If Celgene does not notify Prothena that it desires to exercise its Right of First Negotiation [***], or the Parties do not enter into a definitive agreement [***], then Prothena (or its Affiliates, as applicable) may negotiate and enter into an agreement with respect to the Grant with a Third Party [***]. For the avoidance of doubt, this Section 4.2.2 [***]. For clarity, [***].

4.3Master Collaboration Agreement. For the avoidance of doubt, the provisions of this Article 4 shall not limit in any way the provisions of Article 5 of the Master Collaboration Agreement.

4.4Celgene Exclusivity.

4.4.1Celgene Exclusivity. If Celgene does not exercise the Phase 1 Option for the Licensed Program prior to the end of the Phase 1 Option Term, then, for a period of five (5) years following the expiration of such Phase 1 Option Term (the “Celgene Exclusivity Term”), neither Celgene nor its Affiliates will, anywhere in the Territory, alone or with or through any Third Party, either (a) sell any Competing Antibody that has an approved label for treatment of an Indication for which Celgene or its Affiliates has conducted a Registration Enabling Clinical Trial for a Licensed Product hereunder (as set forth in the protocol for such Registration Enabling Clinical Trial) or (b) conduct a Registration Enabling Clinical Trial for any Competing Antibody for treatment of an Indication (as set forth in the protocol for such Registration Enabling Clinical Trial) for which Celgene has conducted a Registration Enabling Clinical Trial for a Licensed Product hereunder (as set forth in the protocol for such Registration Enabling Clinical Trial) (provided that, for the avoidance of doubt, this Section 4.4.1 shall not prohibit (i) use of an Competing Antibody as a comparator in a Registration Enabling Clinical Trial or (ii) Celgene or any of its Affiliates providing proprietary products (that are not Competing Antibodies) to a Third Party for such Third Party’s use in a clinical trial of Competing Antibodies), in each case of (a) and (b), other than Celgene’s exercise of its rights and performance of its obligations with respect to Licensed Antibodies and Licensed Products pursuant to this Agreement (including engaging Third Party subcontractors to perform the such rights and obligations in accordance with this Agreement). As used herein, the term “Competing Antibody” means any Antibody that Targets the Licensed Target, including any product that incorporates any such Antibody; provided that Competing Antibody shall not include (a) any Antibody (or any product that incorporates any such Antibody) that was Developed or Commercialized by or on behalf of Celgene or any of its Affiliates prior to the Effective Date or (b) any Related Antibodies, or other improvements or modifications, to the

Antibody in the foregoing clause (a) or products that incorporate such Related Antibodies or improvements or modifications.

4.4.2Exceptions for Change of Control. Notwithstanding the provisions of Section 4.4.1, if during the Celgene Exclusivity Term, Celgene (or any of its Affiliates) undergoes a Change of Control with a Third Party who (itself or through any of its Affiliates existing prior to the date of the Change of Control) owns or has rights to a Competing Antibody (but excluding any Licensed Antibody or Licensed Product) that is in ongoing clinical development or being commercialized by such Third Party (or its Affiliate) as of the date of the Change of Control (a “Celgene Acquired Competing Antibody”), then Celgene and its Affiliates (including the acquiring Person in the Change of Control (and such acquiring Person’s Affiliates)) shall not be in breach of the provisions of Section 4.4.1 as a result of [***]; provided that (i) such activities are conducted independently of the activities of this Agreement and without use of any Prothena IP [***] and (ii) no personnel who are conducting any Registration Enabling Clinical Trial activities pursuant to this Agreement are involved in the conduct of Registration Enabling Clinical Trial activities with respect to the Celgene Acquired Competing Antibody.

ARTICLE 5
FINANCIAL TERMS

5.1Option Exercise Fee. Subject to Section 3.2 of the Master Collaboration Agreement, the Parties acknowledge and agree that Celgene will pay the IND Option Exercise Fee (as defined in the Master Collaboration Agreement) for the Licensed Program in accordance with the Master Collaboration Agreement.

5.2Royalties.

5.2.1Licensed Product Royalties. Subject to the terms of this Section 5.2 (and subject further to Section 5.5), Celgene shall pay Prothena royalties on Annual Net Sales, on a Licensed Product-by-Licensed Product basis during the applicable Royalty Term, equal to the following portions of Annual Net Sales of the applicable Licensed Product multiplied by the applicable royalty rate set forth below for such portion of Annual Net Sales during the applicable Royalty Term for each such Licensed Product, which royalties shall be paid in accordance with Section 5.2.7 (the “Per Licensed Product Annual Net Sales”). For clarity, the royalties (and royalty tiers) shall be calculated separately on a Licensed Product-by-Licensed Product basis.


Per Licensed Product Annual Net Sales for a Given Licensed Product in a Given Calendar Year			Royalty Rate
Portion of Per Licensed Product Annual Net Sales of a given Licensed Product in a given Calendar Year above [***]			[***]%
Portion of Per Licensed Product Annual Net Sales of a given Licensed Product in a given Calendar Year above [***]			[***]%
Portion of Per Licensed Product Annual Net Sales of a given Licensed Product in a given Calendar Year above [***]			[***]%
Portion of Per Licensed Product Annual Net Sales of a given Licensed Product in a given Calendar Year above [***]			[***]%
Portion of Per Licensed Product Annual Net Sales of a given Licensed Product in a given Calendar Year above [***]			[***]%
Portion of Per Licensed Product Annual Net Sales of a given Licensed Product in a given Calendar Year above [***]			[***]%
Portion of Per Licensed Product Annual Net Sales of a given Licensed Product in a given Calendar Year above [***]			[***]%
Portion of Per Licensed Product Annual Net Sales of a given Licensed Product in a given Calendar Year above [***]			[***]%
Portion of Per Licensed Product Annual Net Sales of a given Licensed Product in a given Calendar Year [***]			[***]%
Portion of Per Licensed Product Annual Net Sales of a given Licensed Product in a given Calendar Year above [***]			[***]%

The applicable royalty rate set forth in the table above will apply only to that portion of the Per Licensed Product Annual Net Sales of a given Licensed Product during a given Calendar Year that falls within the indicated range. For clarity, (i) if no royalty is payable on a given unit of Licensed Product (e.g., following the Royalty Term for such Licensed Product), then the Net Sales of such unit of Licensed Product shall not be included for purposes of determining the royalties or royalty tiers and (ii) Net Sales of a given Licensed Product will not be combined with Net Sales of any other Licensed Product for purposes of determining the foregoing royalties or

royalty tiers. Only one royalty shall be payable by Celgene to Prothena for each sale of a Licensed Product.

By way of example, if Per Licensed Product Annual Net Sales of a given Licensed Product by Celgene, its Affiliates and Sublicensees were $[***] for a given Calendar Year, then the royalties payable with respect to such Per Licensed Product Annual Net Sales for such Licensed Product for such Calendar Year, subject to adjustment as set forth in this Section 5.2, would be: [***].

5.2.2Royalty Term. Celgene’s royalty obligations to Prothena under Section 5.2.1 shall apply on a Licensed Product-by-Licensed Product basis in the Territory only during the applicable Royalty Term for such Licensed Product. Following expiration of the applicable Royalty Term for a given Licensed Product, as applicable, no further royalties will be payable in respect of sales of such Licensed Product in the Territory and thereafter the license granted to Celgene hereunder with respect to such Licensed Product will automatically become fully paid-up, perpetual, irrevocable and royalty-free.

5.2.3Reductions.

(a)Reserved.

(b)Royalty Reduction for Biosimilar Product. If, on a Licensed Product-by-Licensed Product and Calendar Quarter-by-Calendar Quarter basis in the Territory,

(i)[***]; or

(ii)[***];

then the royalties payable with respect to Per Licensed Product Annual Net Sales of such Licensed Product pursuant to Section 5.2.1 during such Calendar Quarter shall be reduced to [***] of the royalties otherwise payable pursuant to Section 5.2.1. [***]

5.2.4Royalty Offset for Third Party Payments. If Celgene (or any of its Affiliates or Sublicensees) obtains a right or license under intellectual property of a Third Party (whether prior to, or after, the Effective Date), where the research, development, making, using, selling, offering for sale, or importing of any Licensed Product (or any Licensed Antibody contained in such Licensed Product) by or on behalf of Celgene (or any of its Affiliates or Sublicensees) would result in a payment to such Third Party, then Celgene may deduct from the royalty payments that would otherwise have been due under Section 5.2.1 with respect to Per Licensed Product Annual Net Sales in a particular Calendar Quarter, an amount equal to [***] of the amount of [***] (“Celgene Third Party Payments”) during such Calendar Quarter. Notwithstanding the foregoing, in no event shall the royalties payable [***] in any Calendar Quarter by operation of this Section 5.2.4; [***].

5.2.5Cumulative Effect of Royalty Reductions and Offsets. In no event shall the royalty reductions and offsets described in Sections 5.2.3(a), 5.2.3(b) and 5.2.4, alone or together, reduce the royalties payable by Celgene for a given Calendar Quarter pursuant to Section 5.2.1 to less than [***] of the amounts otherwise payable by Celgene for a given Calendar Quarter pursuant to Section 5.2.1. [***]

5.2.6Compulsory Licenses. If a compulsory license is granted to a Third Party with respect to a Licensed Product in the Territory with a royalty rate lower than the royalty rate provided by Section 5.2.1 (as adjusted pursuant to Section 5.2.3), then the royalty rate to be paid by Celgene on Per Licensed Product Annual Net Sales under Section 5.2.1 shall be [***].

5.2.7Payment of Royalties. Celgene shall: (a) within [***] following the end of each Calendar Quarter in which a royalty payment pursuant to Section 5.2.1 accrues, provide to Prothena a report specifying for such Calendar Quarter (i) the number of Licensed Products sold that are subject to such royalty, (ii) the Per Licensed Product Annual Net Sales that are subject to such royalty, (iii) the applicable royalty rate under this Agreement, (iv) the royalty calculation and royalties payable in U.S. Dollars and (v) any reduction to the royalty applied by Celgene pursuant to any one or more of Sections 5.2.3 and 5.2.4; and (b) make the royalty payments owed to Prothena hereunder in accordance with such royalty report in arrears, within [***] from the end of the Calendar Quarter in which such payment accrues.

5.3Regulatory Milestones.

5.3.1Regulatory Milestones. Subject to the terms of this Section 5.3 (and subject further to Section 5.5), Celgene will notify Prothena within [***] days following the first achievement by Celgene under this Agreement and after the Effective Date of each milestone event described below in this Section 5.3 with respect to the first (and only the first) Licensed Product to achieve such milestone event under this Agreement, and Celgene shall thereafter pay the applicable amounts set forth below associated with the applicable milestone event in accordance with Section 5.3.2 (each, a “Regulatory Milestone Payment”):


Regulatory Approval Milestone Event			Regulatory Milestone Payment
1.Receipt under this Agreement of all Regulatory Approvals for a Licensed Product for the first Select Indication in the U.S. issued by the FDA; [***]			[*] Dollars ($[*])
1.Receipt under this Agreement of all Regulatory Approvals for a Licensed Product for a second Select Indication [*]in the U.S. issued by the FDA; [*]			[*] Dollars ($[*])

Each of the foregoing milestones in this Section 5.3.1 shall be payable a maximum of one (1) time as set forth in the foregoing chart regardless of the number of Licensed Products achieving the applicable milestone event (i.e., a maximum of two (2) Regulatory Milestone Payments may be made pursuant to this Section 5.3.1), and no Regulatory Milestone Payment shall be due hereunder for subsequent or repeated achievement of such milestone event. For the avoidance of doubt, the maximum amount payable by Celgene pursuant to this Section 5.3.1 is Ninety Million Dollars ($90,000,000) assuming that each of the milestone events in this Section 5.3.1 were achieved.

5.3.2Invoice and Payment of Regulatory Milestone Payments. Following receipt of notification by Celgene to Prothena that Celgene has achieved the applicable milestone

event triggering a Regulatory Milestone Payment hereunder, Prothena shall invoice Celgene for the applicable Regulatory Milestone Payment, and Celgene shall pay such Regulatory Milestone Payment within [***] after receipt of the invoice therefor.

5.4Sales Milestones.

5.4.1Sales Milestones. Subject to the terms of this Section 5.4 (and subject further to Section 5.5), Celgene will notify Prothena within [***] after the end of the Calendar Quarter during which a given milestone event described below in this Section 5.4 was first achieved by Celgene under this Agreement and after the Effective Date with respect to the Licensed Products, and Celgene shall thereafter pay the applicable amounts set forth below associated with the applicable milestone event in accordance with Section 5.4.2 (each, a “Sales Milestone Payment”):


Sales Milestone Event			Sales Milestone Payment
First achievement of Per Licensed Product Annual Net Sales of the Licensed Products in any single Calendar Year exceeding [*] Dollars ($[*])			[*] Dollars ($[*])
First achievement of Per Licensed Product Annual Net Sales of the Licensed Products in any single Calendar Year exceeding [*] Dollars ($[*])			[*] Dollars ($[*])
First achievement of Per Licensed Product Annual Net Sales of the Licensed Products in any single Calendar Year exceeding [*] Dollars ($[*])			[*] Dollars ($[*])
First achievement of Per Licensed Product Annual Net Sales of the Licensed Products in any single Calendar Year exceeding [*] Dollars ($[*])			[*] Dollars ($[*])

Each of the foregoing milestones in this Section 5.4.1 shall be payable a maximum of one (1) time as set forth in the foregoing chart regardless of the number of times the applicable milestone event was achieved (i.e., a maximum of four (4) Sales Milestone Payments may be made pursuant to this Section 5.4.1), and no Sales Milestone Payment shall be due hereunder for subsequent or repeated achievement of such milestone event. For the avoidance of doubt, the maximum amount payable by Celgene pursuant to this Section 5.4.1 is Three Hundred Seventy-Five Million Dollars ($375,000,000) assuming that each of the milestone events in this Section 5.4.1 were achieved.

5.4.2Invoice and Payment of Sales Milestone Payments. Following receipt of notification by Celgene to Prothena that Celgene has achieved the applicable milestone event triggering a Sales Milestone Payment hereunder, Prothena shall invoice Celgene for the

applicable Sales Milestone Payment, and Celgene shall pay such Sales Milestone Payment within [***] after receipt of the invoice therefor.

5.5Additional Payment Terms.

5.5.1Currency. All payments hereunder shall be made in U.S. Dollars by wire transfer to a bank designated in writing by Prothena. Conversion of sales recorded in local currencies to Dollars shall be performed in a manner consistent with Accounting Standards and Celgene’s normal practices used to prepare its audited financial statements for internal and external reporting purposes.

5.5.2Taxes; Withholding.

(a)Generally. Each Party will pay any and all income taxes levied on account of all payments it receives under this Agreement except as otherwise provided in this Section 5.5.2.

(b)Tax Withholding. Each Party shall be entitled to deduct and withhold from any amounts payable under this Agreement such taxes as are required to be deducted or withheld therefrom under any provision of Applicable Law. The Party that is required to make such withholding (the “Paying Party”) will (i) deduct those taxes from such payment, (ii) timely remit the taxes to the proper taxing authority, and (iii) send evidence of the obligation together with proof of tax payment to the other Party (the “Payee Party”) on a timely basis following that tax payment; provided, however, that before making any such deduction or withholding, the Paying Party shall give the Payee Party notice of the intention to make such deduction or withholding (such notice shall include an explanation of the reason for and the calculation of the proposed deduction or withholding and shall be given before such deduction or withholding is required in order for such Payee Party to obtain reduction of or relief from such deduction or withholding). Each Party agrees to reasonably cooperate with the other Party in claiming refunds or exemptions from such deductions or withholdings under any relevant agreement or treaty which is in effect to ensure that any amounts required to be withheld pursuant to this Section 5.5.2(b) are reduced in amount to the fullest extent permitted by Applicable Law. In addition, the Parties shall cooperate in accordance with Applicable Laws to minimize indirect taxes (such as value added tax, sales tax, consumption tax and other similar taxes (“Indirect Taxes”)) in connection with this Agreement.

(c)Tax Gross-Up. Notwithstanding the foregoing, if (a) any Party redomiciles, assigns its rights or obligations or extends its rights under this Agreement, (b) as a result of such redomiciliation, assignment or extension, such Party (or its assignee) is required by Applicable Law to [***] or such redomiciliation, assignment or extension results in [***], and (c) such [***] exceed the amount of [***] that would have been applicable but for such redomiciliation, assignment or extension, then any such amount payable shall [***] so that, after making all required [***], the Payee Party (or its assignee) [***]. The obligation [***] shall not apply to the extent [***], and (B) shall be [***]. For purposes of the preceding sentence, “Tax Benefit” shall mean any cash refund or credit for Taxes resulting in a reduction in the amount of Taxes otherwise owed by the Payee Party as a result of [***] relating to payments by the Paying Party, as reasonably determined by Payee Party. Solely for purposes of this Section 5.5.2(c), a

Party’s “domicile” shall include its jurisdiction of incorporation or tax residence and a “redomiciliation” shall include a reincorporation or other action resulting in a change in tax residence of the applicable Party or its assignee, or resulting in the attribution of any amounts payable to a branch or permanent establishment located outside the country of tax residence of the applicable Party or its assignee

(d)Tax Documentation. Prothena has provided a properly completed and duly executed IRS Form W-8BEN-E to Celgene. Prior to the receipt of any payment under this Agreement, each recipient Party (and any other recipient of payments under this Agreement) shall, to the extent it is legally permitted to, provide to the other Party, at the time or times reasonably requested by such other Party or as required by Applicable Law, such properly completed and duly executed documentation (for example, IRS Forms W-8 or W-9 or foreign equivalents) as will permit payments made under this Agreement to be made without, or at a reduced rate of, withholding for taxes

5.5.3Other U.S. License Agreements. For the avoidance of doubt, a Licensed Product hereunder will only be eligible for milestone and royalty payments under this Agreement, and shall not be eligible for, or counted towards, milestone or royalty payments under any other U.S. License Agreement (i.e., a given Licensed Product will be eligible for, and counted towards, milestone and royalty payments only under one U.S. License Agreement).

5.6Records Retention by Celgene; Review by Prothena.

5.6.1Records. With respect to royalty and milestone payments to be made under Sections 5.2 or 5.4 of this Agreement, Celgene agrees to keep and shall procure that its Affiliates keep, for at least [***] years from the end of the Calendar Year to which they pertain, complete and accurate records of sales by Celgene or its Affiliates (including sales by Sublicensees), as the case may be, of each Licensed Product, in sufficient detail to allow the accuracy of the payments made hereunder to be confirmed.

5.6.2Review. Subject to the other terms of this Section 5.6.2, during the Term, at the request of Prothena, which shall not be made more frequently than [***], upon at least [***] days’ prior written notice from Prothena, [***], Celgene shall permit [***] to inspect (during regular business hours) the relevant records required to be maintained by Celgene under Section 5.6.1; provided that such audit right shall not apply to records beyond [***] years from the end of the Calendar Year to which they pertain. In every case the [***] to authorized representatives of the Parties and the purposes germane to Section 5.6.1. Results of any such review shall be binding on both Parties absent manifest error. The [***] shall report to Prothena only whether the particular amount being audited was accurate, and if not, the amount of any discrepancy, and the [***] shall not report any other information to Prothena. Prothena shall treat the results of any such [***] review of Celgene’s records as Confidential Information of Celgene subject to the terms of Article 7. If any review reveals a deficiency or overpayment in the calculation and/or payment of royalties or Sales Milestone Payments by Celgene, then (a) Celgene or Prothena as applicable shall promptly pay (or refund, as applicable) the other Party the amount of such deficiency or overpayment, as applicable, and (b) if such deficiency is by more than the greater of (i) [***] of the aggregate amounts owed by Celgene or (ii) [***],

Celgene shall, within thirty (30) days after receipt of an invoice therefor, pay the reasonable out-of-pocket costs and expenses incurred by Prothena for the [***] in connection with the review.

5.6.3Records Final. Upon the expiration of [***] years following the end of a given Calendar Year, subject and without prejudice to the determination of any review commenced prior to such [***] anniversary pursuant to Section 5.6.2, the calculation of royalties and Sales Milestone Payments payable with respect to such Calendar Year shall be binding and conclusive upon Prothena, and Celgene (and its Affiliates) shall be released from any liability or accountability with respect to such royalties for such Calendar Year.

5.7Prothena Third Party Agreements. Notwithstanding anything to the contrary herein, Prothena shall be solely responsible for all costs and payments of any kind (including all upfront fees, annual payments, milestone payments and royalty payments) arising under any agreements between Prothena (or any of its Affiliates) and any Third Party (including under any In-License Agreement or other Existing Program Agreement), which costs or payments arise in connection with, or as a result of, the activities hereunder, including the Development, Manufacture or Commercialization of Licensed Antibodies or Licensed Products.

5.8Diagnostic Products. Notwithstanding anything to the contrary contained herein, [***].

5.9Additional Provisions. Notwithstanding anything to the contrary herein, the terms and provisions of this Article 5 are subject to Section 11.7 of the Master Collaboration Agreement and Sections 10.9 and 10.12 of this Agreement.

ARTICLE 6
LICENSES; INTELLECTUAL PROPERTY

6.1License to Celgene. Subject to the terms and conditions of this Agreement, Prothena hereby grants to Celgene an exclusive right and license, with the right to grant sublicenses (through multiple tiers), under the Prothena IP to research, develop (including Develop), make (including Manufacture), have made (including have Manufactured), use, offer for sale, sell, import, Commercialize and otherwise exploit Licensed Antibodies and Licensed Products, including Diagnostic Products, in the Field in the Territory.

6.2License to Celgene for Other Targets. In the event that, during the Term, Celgene modifies a Licensed Program Antibody in the course of its Development activities hereunder such that such Licensed Program Antibody specifically binds to a target other than (i) the Licensed Target or (ii) any other Collaboration Target (e.g., a bispecific antibody), then, at the request of Celgene, Celgene and Prothena shall negotiate in good faith a license under intellectual property of Prothena or its Affiliates, as applicable, that is specific to such other target or Antibodies to such other target.

6.3Rights Retained by the Parties. For purposes of clarity, each Party retains all rights under Know-How and Patents Controlled by such Party not expressly granted to the other Party pursuant to this Agreement. In addition, Prothena retains the right to perform the Prothena Ongoing Program Activities in accordance with this Agreement.

6.4No Implied Licenses. Except as explicitly set forth in this Agreement, the Master Collaboration Agreement, any other U.S. License Agreement or any Global License Agreement, neither Party shall be deemed by estoppel or implication to have granted to the other Party any license or other right to any intellectual property of such Party.

6.5Insolvency. In the event that this Agreement is terminated due to the rejection of this Agreement by or on behalf of Prothena due to an Insolvency Event, all licenses and rights to licenses granted under or pursuant to this Agreement by Prothena to Celgene are and shall otherwise be deemed to be licenses of rights to “intellectual property”. The Parties agree that Celgene, as a licensee of such rights under this Agreement, shall retain and may fully exercise all of its rights and elections under any applicable insolvency statute, and that upon commencement of an Insolvency Event by or against Prothena, Celgene shall be entitled to a complete duplicate of or complete access to (as Celgene deems appropriate), any such intellectual property and all embodiments of such intellectual property. Such intellectual property and all embodiments thereof shall be promptly delivered to Celgene (i) upon any such commencement of a bankruptcy proceeding (or other Insolvency Event) upon written request therefore by Celgene, unless Prothena elects to continue to perform all of its obligations under this Agreement or (ii) if not delivered under (i) above, upon the rejection of this Agreement by or on behalf of Prothena, then upon written request therefore by Celgene. The provisions of this Section 6.5 shall be (1) without prejudice to any rights Celgene may have arising under any applicable insolvency statute or other Applicable Law and (2) effective only to the extent permitted by Applicable Law.

6.6Ownership.

6.6.1Inventorship. Notwithstanding the provisions of Section 11.8.1, inventorship of Know-How shall be determined by application of U.S. patent law pertaining to inventorship, and, except as provided for in Sections 6.6.2, 6.6.3 and 6.6.4, ownership of Know-How shall be determined by inventorship.

6.6.2Ownership of Collaboration IP and Celgene IP.

(a)Prothena. As between the Parties (including their respective Affiliates), Prothena will retain all right, title and interest in and to all Prothena Licensed Collaboration IP, except to the extent that any such rights are licensed or granted to Celgene under this Agreement or the Master Collaboration Agreement. Prothena shall [***] that all Patents, Know-How and other intellectual property (other than Licensed Program IP and Celgene IP, if any) utilized in the performance of the Licensed Program under the Master Collaboration Agreement falls within the Prothena Licensed Collaboration IP and is and remains during the Term Controlled by Prothena such that Prothena has the full rights to grant the rights and licenses to the Prothena Licensed Collaboration IP to Celgene hereunder (including that such Patents, Know-How and other intellectual property remains unencumbered such that Prothena is able to grant such rights and licenses to Celgene).

(b)Celgene. As between the Parties (including their respective Affiliates), Celgene (or its Affiliate) will retain all right, title and interest in and to all Celgene IP, including all rights to Prosecute and Maintain, and enforce any such Celgene IP, and no rights or licenses are granted to Prothena hereunder with respect to any Celgene IP.

6.6.3Ownership of Licensed Program IP.

(a)Prothena. As between the Parties (including their respective Affiliates), Prothena will solely own and Control all Licensed Program IP. Celgene shall, and hereby does, assign to Prothena all of Celgene’s interest in any and all Licensed Program Know-How that falls within Section 1.47(a)(iii) and all Licensed Program Patents claiming such Licensed Program Know-How. Celgene shall, and shall require its Affiliates to, take all reasonable actions and execute all documents necessary to effect the intent of the preceding sentence. As between the Parties (and their respective Affiliates) and any Third Party, Prothena will solely own and Control all Licensed Program IP; provided that if (a) [***] and (b) [***].

(b)If any Licensed Program IP is created, conceived, discovered, first generated, invented, first made or first reduced to practice pursuant to the Master Collaboration Agreement by any Third Party that is in contractual privity with or otherwise engaged by Prothena [***] will include in such agreement with such Third Party an obligation to [***] to Prothena [***] such Licensed Program IP to enable Prothena to grant to Celgene a license thereunder as provided in this Agreement for the duration of this Agreement.

6.6.4Joint IP. The Parties shall each own an equal, undivided interest in: (a) any and all Know-How that is created, conceived, discovered, first generated, invented, first made or first reduced to practice, in each case, jointly by or on behalf of Prothena or its Affiliates, on the one hand, and Celgene or its Affiliates, on the other hand, pursuant to the conduct of activities under this Agreement at any time during the Term (the “Joint Know-How”), and (b) any Patents that claim any Joint Know-How (the “Joint Patents”, together with Joint Know-How the “Joint IP”). Each Party shall assign, and hereby assigns, to the other Party, a joint equal and undivided interest in and to such Joint IP (provided, however, that for clarity, the foregoing joint ownership rights with respect to Joint IP shall not be construed as granting, conveying or creating any license or other rights to any of the other Party’s other intellectual property, unless otherwise expressly set forth in this Agreement), and at the request of a Party, the other Party will execute such documents (including any necessary assignments) to effect such joint ownership of such Joint IP. Each Party shall have the right to disclose (except as otherwise set forth in Section 7.2) and exploit the Joint IP without a duty of seeking consent or accounting to the other Party except as expressly provided in this Agreement; provided that, such rights shall be subject to the rights and licenses granted to Celgene and Prothena hereunder (or under the Master Collaboration Agreement, any Global License Agreement or any other U.S. License Agreement), including the obligations of Prothena as set forth in Article 4.

6.7Patent Liaisons. Prior to the end of the Phase 1 Option Term for the Licensed Program, the Patent Committee under the Master Collaboration Agreement shall remain established, and shall continue to perform the functions set forth in Section 4.3 and Article 7 of the Master Collaboration Agreement with respect to the Prothena Licensed Collaboration Patents and Licensed Program Patents. Following the end of the Phase 1 Option Term for the Licensed Program, the Patent Committee under the Master Collaboration Agreement shall no longer oversee or review any matters with respect to the Prothena Licensed Collaboration Patents or Licensed Program Patents, and promptly following the end of the Phase 1 Option Term for the Licensed Program, each Party shall appoint an individual to act as a patent liaison for such Party pursuant to this Agreement (each, a “Patent Liaison”). The Patent Liaisons shall be the primary

point of contact for the Parties regarding intellectual property-related activities and matters contemplated by this Agreement, as and to the extent requested by Celgene from time to time. The name and contact information for each Party’s Patent Liaison, as well as any replacement(s) chosen by such Party, in its sole discretion, from time to time, shall be promptly provided to the other Party in accordance with Section 11.2.

6.8Prosecution and Maintenance of Prothena Licensed Collaboration Patents and Licensed Program Patents.

6.8.1Prior to End of the Phase 1 Option Term. Prior to the expiration of the Phase 1 Option Term for the Licensed Program, the provisions of Section 7.7 of the Master Collaboration Agreement shall apply with respect to the Prothena Licensed Collaboration Patents and Licensed Program Patents.

6.8.2Following Phase 1 Option Term. Following the expiration of the Phase 1 Option Term for the Licensed Program, the provisions of this Section 6.8.2 shall apply with respect to the Prothena Licensed Collaboration Patents and Licensed Program Patents.

(a)[***] First Right. Subject to Section 6.8.2(b), [***] shall be required to, and shall, Prosecute and Maintain the Prothena Licensed Collaboration Patents and Licensed Program Patents in the Territory. All such Prosecution and Maintenance by [***] shall be through patent counsel reasonably acceptable to [***]. [***] shall keep [***] informed as to material developments with respect to the Prosecution and Maintenance of such Patents including by providing copies of all substantive office actions, examination reports, communications or any other substantive documents to or from any patent office, including notice of all interferences, reissues, re-examinations, inter partes reviews, derivations, post grant proceedings, oppositions or requests for patent term extensions. [***] shall also provide [***] with a reasonable opportunity to comment substantively on the Prosecution and Maintenance of such Prothena Licensed Collaboration Patents and Licensed Program Patents prior to taking material actions (including the filing of initial applications), and will in good faith incorporate any comments made by and actions recommended in good faith by [***], provided, however, that [***] provides its comments reasonably in advance of any applicable filing deadlines.

(b)[***] Back-Up Right. If [***] in the Territory decides not to file a Prothena Licensed Collaboration Patent or Licensed Program Patent, in each case other than a Prothena Platform Patent, or intends to allow such Patent to lapse or become abandoned without having first filed a substitute, it shall notify and consult with [***] of such decision or intention at least thirty (30) days prior to the date upon which the subject matter of such Patent shall become unpatentable or such Patent shall lapse or become abandoned, and [***] shall thereupon have the right (but not the obligation) upon written notice to [***] to assume the Prosecution and Maintenance thereof at [***] expense with counsel of its choice ([***]). For clarity, the provisions of this Section 6.8.2(b) shall not limit Prothena’s obligations to Prosecute and Maintain the Prothena Licensed Collaboration Patents and Licensed Program Patents in the Territory as set forth in Section6.8.2(a).

(c)Cooperation in Prosecution and Maintenance.

(i)Further Assurances. If Celgene determines to undertake the Prosecution and Maintenance of a Prothena Licensed Collaboration Patent or Licensed Program Patent in accordance with this Section 6.8.2, Prothena agrees to make its employees, agents and consultants reasonably available to Celgene (and to Celgene’s authorized attorneys, agents or representatives) to enable Celgene to undertake such Prosecution and Maintenance. In addition, Prothena shall (and shall cause its Affiliates and its and their employees, agents and consultants to) provide reasonable assistance to Celgene (and to Celgene’s authorized attorneys, agents or representatives) to enable Celgene to undertake such Prosecution and Maintenance, including by executing powers of attorney and other documents for Celgene to undertake such Prosecution and Maintenance.

(ii)Assistance. The Parties shall reasonably cooperate with one another with respect to the Prosecution and Maintenance of the Prothena Licensed Collaboration Patents and Licensed Program Patents for which either Party is responsible for Prosecution and Maintenance pursuant to this Section 6.8.2. [***], the Parties shall cooperate with one another to [***], in each case that are applicable to the Licensed Target or Licensed Program Antibody, as applicable, if practicable [***].

(d)Costs of Prosecution and Maintenance. Except as otherwise expressly set forth in this Section 6.8.2, each Party shall be responsible for all costs and expenses associated with its Prosecution and Maintenance activities under this Section 6.8.2 with respect to Prothena Licensed Collaboration Patents and Licensed Program Patents for which it is responsible pursuant to Sections 6.8.2(a) or 6.8.2(b), as applicable. Notwithstanding the foregoing provisions of this Section 6.8.2, [***]. If any Prothena Licensed Collaboration Patents or Licensed Program Patents claim or cover [***], and such Prothena Licensed Collaboration Patent or Licensed Program Patent, as applicable, is [***] costs for the Prosecution and Maintenance of such Prothena Licensed Collaboration Patent or Licensed Program Patent, as applicable, pursuant to Section [***].

6.9Enforcement of Prothena Licensed Collaboration Patents and Licensed Program Patents.

6.9.1Prior to the end of the Phase 1 Option Term. Prior to the end of the Phase 1 Option Term for the Licensed Program, the provisions of Section 7.7 of the Master Collaboration Agreement shall apply with respect to the Prothena Licensed Collaboration Patents and Licensed Program Patents.

6.9.2Following Phase 1 Option Term. Following the end of the Phase 1 Option Term for the Licensed Program, the provisions of this Section 6.9.2 shall apply with respect to the Prothena Licensed Collaboration Patents and Licensed Program Patents in the Territory, and the provisions of Master Collaboration Agreement shall continue to apply with respect to the Prothena Licensed Collaboration Patents and Licensed Program Patents outside the Territory.

(a)Notice. If any Party learns of an infringement or threatened infringement by a Third Party of any Prothena Licensed Collaboration Patent or Licensed Program Patent, in each case other than a Prothena Platform Patent, in the Territory (including in

connection with any Biosimilar Application referencing a Licensed Product (regardless of whether such notice or copy is provided under any Applicable Laws) including under the BPCIA or the United States Patient Protection and Affordable Care Act or its successor provisions, or any similar provisions in a country outside the United States, as applicable) such Party shall promptly notify the other Party and shall provide such other Party with available evidence of such infringement, and following such notification, the Parties shall confer.

(b)[***] First Right. Subject to the remaining provisions of this Section 6.9.2, [***] shall have the first right, but not the obligation, to institute, prosecute, and control any action or proceeding (which may include settlement or otherwise seeking to secure the abatement of such infringement) with respect to any infringement of any (i) Prothena Licensed Collaboration Patent or (ii) Licensed Program Patent, in each case other than a Prothena Platform Patent, (including in connection with any Biosimilar Application referencing a Licensed Product (regardless of whether such notice or copy is provided under any Applicable Laws), including under the BPCIA or the United States Patient Protection and Affordable Care Act or its successor provisions, or any similar provisions in a country outside the United States, as applicable), by counsel of its own choice, in [***] own name [***] and under [***] direction and control, including the right to control the defense of any challenges to such Patents as a counterclaim in such infringement proceeding as well as the defense of declaratory judgment actions. Prothena retains all rights to enforce the Prothena Platform Patents against any actual or threatened infringement.

(c)[***] Back-Up Right. If [***] determines not to institute an action or proceeding with respect to a given infringement of any Prothena Licensed Collaboration Patent or Licensed Program Patent pursuant to Section 6.9.2(b), it shall notify and consult with [***] of such decision, and, subject to the remaining provisions of this Section 6.9.2, [***] shall thereupon have the right (but not the obligation) to institute an action or proceeding with respect to such infringement of such Prothena Licensed Collaboration Patent or Licensed Program Patent, as applicable, at [***] expense with counsel of its choice. Notwithstanding the foregoing provisions of this Section 6.9.2(c), if [***] has any reasonable grounds for believing that [***] exercise of its backup enforcement right with respect to any Patent as set forth in this Section 6.9.2(c) could reasonably be detrimental to the patent protection of any Licensed Antibodies or Licensed Products, then [***] shall not be permitted to enforce such Patent without the prior consent of [***], in [***] discretion.

(d)[***]. Notwithstanding the foregoing Sections 6.9.2(b) and 6.9.2(c), the Parties must agree in writing prior to either Party initiating any action or proceeding with respect to any infringement of any Prothena Licensed Collaboration Patent or Licensed Program Patent with respect to any [***].

(e)Joinder. In the case of any enforcement action or proceeding set forth in Section [***] controlled by Celgene, Prothena will (and will cause its Affiliates to) join any such action or proceeding as a party at Celgene’s expense (and Prothena will use commercially reasonable efforts to cause any Third Party as necessary to join such action or proceeding as a party) if doing so is necessary for the purposes of establishing standing or is otherwise required by Applicable Law to pursue such action or proceeding. Prothena may, at its option, participate in such enforcement action or proceeding at its own expense. In the case of

any enforcement action or proceeding controlled by Prothena pursuant to Section [***], Celgene may, at its option, participate in such enforcement action or proceeding at its own expense. Celgene will join any such action or proceeding controlled by Prothena as a party at Prothena’s expense (and Celgene will use commercially reasonable efforts to cause any Third Party as necessary to join such action or proceeding as a party) if doing so is necessary for the purposes of establishing standing or is otherwise required by Applicable Law to pursue such action or proceeding. Celgene will bear all costs and expenses incurred by it arising out of such enforcement action or proceeding controlled by Celgene, and Prothena will bear all costs and expenses incurred by it arising out of such enforcement action or proceeding controlled by Prothena.

(f)Consultation; Cooperation. The enforcing Party will keep the non-enforcing Party regularly informed of the status and progress of such enforcement efforts with respect to any Prothena Licensed Collaboration Patent or Licensed Program Patent, in each case other than a Prothena Platform Patent. The enforcing Party shall consult with the non-enforcing Party and will take comments of the non-enforcing Party into good faith consideration with respect to the infringement or claim construction of any claim in any such Prothena Licensed Collaboration Patent or Licensed Program Patent. The non-enforcing Party will provide to the enforcing Party reasonable cooperation in such enforcement, at such enforcing Party’s request and expense. In addition, Prothena shall (a) keep Celgene regularly informed of the status and progress of enforcement efforts with respect to any foreign counterparts of such Prothena Licensed Collaboration Patents and Licensed Program Patents and (b) consult with Celgene and will take comments of Celgene into good faith consideration with respect to the infringement or claim construction of any claim in any foreign counterparts of such Prothena Licensed Collaboration Patents and Licensed Program Patents.

(g)Settlement. A settlement or consent judgment or other voluntary final disposition of a suit with respect to the Prothena Licensed Collaboration Patents or Licensed Program Patents, in each case other than a Prothena Platform Patent, under this Section 6.9.2 may be entered into without the consent of the Party not bringing suit; provided, however, that any such settlement, consent judgment or other disposition of any action or proceeding by the Party bringing suit under this Section 6.9.2 shall not, without the prior written consent of the Party not bringing suit, such consent not to be unreasonably withheld, (i) impose [***] on the Party not bringing suit or any of its Affiliates, (ii) conflict with [***] the scope of the subject matter claimed in the applicable Prothena Licensed Collaboration Patents or Licensed Program Patents, (iii) [***], include the grant of any license, covenant or other rights to any Third Party that would conflict with [***] the scope of the rights or licenses granted to Celgene under this Agreement, the Master Collaboration Agreement, any Global License Agreement or any other U.S. License Agreement, or (iv) [***] affect the rights granted Celgene hereunder with respect to [***] Prothena Licensed Collaboration Patents or Licensed Program Patents.

(h)Costs and Recoveries. Except as otherwise set forth in this Section 6.9.2, each Party shall bear all of its costs incurred in connection with its activities under this Section 6.9.2. Any damages or other monetary awards recovered in any action, suit or proceeding brought under this Section 6.9.2 to the extent related to any Prothena Licensed Collaboration Patents or Licensed Program Patents shall be shared as follows:

(i)the amount of such recovery actually received by the Party controlling such action shall first be applied to reimburse costs and expenses incurred by each Party in connection with such action (including, for this purpose [***]); and

(ii)any remaining proceeds shall be (A) for any action controlled by Celgene, retained by, or provided to, Celgene and [***], and (B) for any action controlled by Prothena, retained by, or provided to, Prothena [***].

(i)Biosimilar Applications. Notwithstanding the foregoing provisions of this Section 6.9.2, if either Party receives a copy of a Biosimilar Application referencing a Licensed Product, whether or not such notice or copy is provided under any Applicable Laws (including under the BPCIA, the United States Patient Protection and Affordable Care Act, or its successor provisions, or any similar provisions in a country outside the United States, as applicable), or otherwise becomes aware that such a Biosimilar Application has been submitted to a Regulatory Authority for marketing authorization (such as in an instance described in 42 U.S.C. §262(l)(2)), the remainder of this Section 6.9.2(i) shall apply. Such Party shall promptly, but in any event within [***] Business Days, notify the other Party. The owner of the relevant Patents shall then seek permission to view the Biosimilar Application, information regarding the process or processes used to manufacture the product that is the subject of the Biosimilar Application, and related confidential information from the filer of the Biosimilar Application if necessary under 42 U.S.C. §262(l)(1)(B)(iii). If either Party receives any equivalent or similar communication or notice in the United States or any other jurisdiction, the Party receiving such communication or notice shall within [***] Business Days notify the other Party of such communication or notice to the extent permitted by Applicable Laws. Regardless of the Party that is the “reference product sponsor,” as defined in 42 U.S.C. §262(l)(1)(A), for purposes of such Biosimilar Application:

(i)[***] the outside counsel and in-house counsel who shall receive confidential access to the Biosimilar Application, information regarding the process or processes used to manufacture the product that is the subject of the Biosimilar Application, and any related confidential information pursuant to 42 U.S.C. §262(l)(1)(B)(ii).

(ii)In each case, after consulting with [***] and considering [***] comments in good faith, [***] shall have the right to (a) list any patents, including those Patents within the Prothena IP, as required pursuant to 42 U.S.C. §262(l)(3)(A) or 42 U.S.C. §262(l)(7), (b) respond to any communications with respect to such lists from the filer of the Biosimilar Application, (c) negotiate with the filer of the Biosimilar Application as to whether to utilize a different mechanism for information exchange other than that specified in 42 U.S.C. §262(l)(1), and (d) as to the Patents that will be subject to the litigation procedure as described in 42 U.S.C. §262(l)(4), decide which Patent or Patents shall be selected for litigation under 42 U.S.C. §262(l)(5)(B)(i)(II), and commence such litigation under 42 U.S.C. §262(l)(6). [***]

(iii)[***] shall cooperate with [***] reasonable requests in connection with the foregoing activities to the extent required or permitted by Applicable Laws. [***] shall consult with [***] prior to identifying any Patents within the Prothena IP to a Third Party as contemplated by this Section 6.9.2(i). [***] shall consider in good faith advice and

suggestions with respect thereto received from [***], and notify [***] of any such lists or communications promptly after they are made.

(iv)Each Party shall within [***] Business Days after receiving any notice of commercial marketing provided by the filer of a Biosimilar Application pursuant to 42 U.S.C. §262(l)(8)(A), notify the other Party. To the extent permitted by Applicable Law, [***] shall have the first right, but not the obligation, to seek an injunction against such commercial marketing as permitted pursuant to 42 U.S.C. §262(l)(8)(B) and to file an action for infringement. [***] Except as otherwise provided in this Section 6.9.2(i), any such action shall be subject to the terms and conditions of Section 6.9.2(a) through 6.9.2(h).

(v)The Parties recognize that procedures other than those set forth above in this Section 6.9.2(i) may apply with respect to Biosimilar Applications. In the event that the Parties determine that certain provisions of Applicable Laws in the United States apply to actions taken by the Parties with respect to Biosimilar Applications under this Section 6.9.2(i), the Parties shall comply with any such Applicable Laws (and any relevant and reasonable procedures established by Parties) in exercising their rights and obligations with respect to Biosimilar Applications under this Section 6.9.2(i). Notwithstanding the provisions of this Section 6.9.2(i), nothing in this Section 6.9.2(i) shall grant any rights to Prothena with respect to any Celgene IP.

6.10Patent Term Extensions. Prothena shall reasonably cooperate with Celgene, including providing reasonable assistance to Celgene (including executing any documents as may reasonably be required), in efforts to seek and obtain patent term restoration or supplemental protection certificates or the like or their equivalents in the Territory, where applicable to Prothena Licensed Collaboration Patents or Licensed Program Patents or any other Patents Controlled by Celgene (or any of its Affiliates), in each case other than a Prothena Platform Patent, including as may be available to the Parties under the provisions of the U.S. Drug Price Competition and Patent Term Restoration Act of 1984, in connection with any Licensed Product. In the event that elections with respect to obtaining such patent term restoration or supplemental protection certificates or the like or their equivalents are to be made in connection therewith, [***] shall have the right to make the election and [***] agrees to abide by such election. Without limiting the foregoing, [***].

6.11Regulatory Data Protection. [***] (or its designee) shall have the sole right to list, with the applicable Regulatory Authorities in the Territory, all applicable Patents (including any Prothena Licensed Collaboration Patents or Licensed Program Patents) for any Licensed Product, including all so called “Purple Book” listings required under the U.S. Public Health Service Act[***]. For the avoidance of doubt, [***] will retain final decision-making authority as to the listing of all applicable Patents for any Licensed Product, regardless of which Party owns such Patent, and [***] shall reasonably assist [***] in connection therewith.

6.12Matters Involving Joint Patents. The Prosecution and Maintenance, and the enforcement and defense, of any Joint Patents shall be jointly managed by the Parties through independent patent counsel (mutually agreed to by the Parties) jointly representing the Parties, including any costs and recoveries regarding same. Prior to either Party publishing any Joint

Know-How, the Parties will discuss if a Joint Patent claiming such Joint Know-How should be filed.

6.13Common Interest Agreement. At the request of either Party, the Parties shall negotiate in good faith to enter into a common interest agreement to govern their discussion of Patent matters.

6.14License Filing. At the request of [***], [***] shall, and shall cause its Affiliates to, assist in any license registration processes with applicable Governmental Authorities that may be available for the protection of [***] interests in this Agreement.

6.15Defense of Claims Brought by Third Parties. If a Party becomes aware of any actual or potential claim that the Development, Manufacture or Commercialization of a Licensed Antibody or Licensed Product by or on behalf of Celgene pursuant to this Agreement infringes the intellectual property rights of any Third Party, such Party shall promptly notify the other Party. In any such instance, the Parties shall as soon as practicable thereafter meet to discuss in good faith regarding the best response to such notice; provided that Celgene shall have the final decision-making authority in connection therewith. Except as set forth in Section 9.2 (and without limiting Celgene’s rights under Section 9.2), Celgene shall have the sole right, but not the obligation, to defend and dispose of (including through settlement or license) such claim. [***] by or on behalf of [***] (or any of its Affiliates or Sublicensees) in connection with the [***], to the extent relating to the Development, Manufacture or Commercialization of a Licensed Antibody or Licensed Product, shall be [***].

ARTICLE 7
CONFIDENTIALITY

7.1Nondisclosure. Each Party agrees that a Party (the “Receiving Party”) receiving Confidential Information of the other Party (the “Disclosing Party”) pursuant to this Agreement shall (a) maintain in confidence such Confidential Information using not less than the efforts such Receiving Party uses to maintain in confidence its own proprietary information of similar kind and value, but in no event less than a reasonable degree of efforts, (b) not disclose such Confidential Information to any Third Party without the prior written consent of the Disclosing Party, except for disclosures expressly permitted pursuant to this Article 7, and (c) not use such Confidential Information for any purpose except those permitted by this Agreement, including, in the case of Celgene, the exercise of the rights and licenses granted to Celgene hereunder (it being understood that this clause (c) shall not create or imply any rights or licenses not expressly granted under this Agreement). The obligations of confidentiality, non-disclosure and non-use under this Section 7.1 shall be in full force and effect during the Term and for a period of [***] years thereafter. The Receiving Party will return all copies of or destroy (and certify such destruction in writing) the Confidential Information of the Disclosing Party disclosed or transferred to it by the other Party pursuant to this Agreement, within [***] days after the termination or expiration of this Agreement; provided, however, that a Party may retain (i) Confidential Information of the other Party to exercise rights and licenses which expressly survive such termination or expiration pursuant to this Agreement, (ii) one (1) copy of all other Confidential Information in archives solely for the purpose of establishing the contents thereof and (iii) Celgene may retain Confidential Information of Prothena in the event that the Parties (or

their respective Affiliates) enter into a Global License Agreement for the Licensed Program, and in such case, Celgene shall not be required to return or destroy any Confidential Information of Prothena. [***] Without limiting the foregoing, [***] will keep confidential, and will cause its Affiliates and its and their employees, consultants, licensees, sublicensees, professional advisors and Affiliates to keep confidential, the [***] on confidentiality terms at least as protective as the confidentiality provisions of this Agreement (without regard to Section 7.3).

7.2Licensed Program Specific Confidential Information. Notwithstanding anything to the contrary contained herein, the Parties agree and acknowledge that any Licensed Program Specific IP shall be deemed to be Confidential Information of Celgene (without regard to Section 7.3), and Celgene shall be deemed to be the Disclosing Party with respect to the Licensed Program Specific IP. As used herein, (a) the term “Licensed Program Specific IP” means, [***]; and (b) the term “Licensed Program Non-Specific IP” means all Prothena Platform Technology within the Prothena Licensed Collaboration Know-How, and other Prothena Licensed Collaboration Know-How and Licensed Program Know-How other than Licensed Program Specific IP. For clarity, Licensed Program Non-Specific IP shall be deemed to be the Confidential Information of Prothena.

7.3Exceptions.

7.3.1General. The obligations in Section 7.1 shall not apply with respect to any portion of the Confidential Information of the Disclosing Party that the Receiving Party can show by competent written proof:

(a)was known to the Receiving Party or any of its Affiliates, without any obligation to keep it confidential or any restriction on its use, prior to disclosure by the Disclosing Party;

(b)is subsequently disclosed to the Receiving Party or any of its Affiliates by a Third Party lawfully in possession thereof and without any obligation to keep it confidential or any restriction on its use;

(c)is published by a Third Party or otherwise becomes publicly available or enters the public domain, either before or after it is disclosed to the Receiving Party, without any breach by the Receiving Party of its obligations hereunder;

(d)is published by a Party in accordance with Section 7.8 without any breach by such Party of its obligations hereunder; or

(e)is independently developed by or for the Receiving Party or its Affiliates without reference to or reliance upon the Disclosing Party’s Confidential Information.

Any combination of features or disclosures shall not be deemed to fall within the foregoing exclusions merely because individual features are published or available to the general public or in the rightful possession of the Receiving Party unless the combination itself and principle of operation are published or available to the general public or in the rightful possession of the Receiving Party.

7.4Authorized Disclosure.

7.4.1Disclosure. Notwithstanding Section 7.1, the Receiving Party may disclose Confidential Information belonging to the Disclosing Party in the following instances:

(a)subject to Section 7.6, to comply with Applicable Law (including the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) or any national securities exchange) or with judicial process (including prosecution or defense of litigation), if, in the reasonable opinion of the Receiving Party’s counsel, such disclosure is necessary for such compliance or for such judicial process (including prosecution or defense of litigation);

(b)is disclosed to governmental or other regulatory agencies in order to obtain Patents or to gain or maintain approval to conduct Clinical Trials or to market Licensed Product under this Agreement, in each case, in accordance with this Agreement, but such disclosure shall only be to the extent reasonably necessary to obtain Patents or authorizations, and provided that reasonable steps are taken to ensure confidential treatment of such Confidential Information (if available);

(c)to any of its officers, employees, consultants, agents or Affiliates (including, (i) in the case of [***], (ii) in the case of either Party, to such Party’s subcontractors for purpose of such subcontractor performing obligations of such Party under this Agreement) as it deems necessary or advisable in the course of conducting activities in accordance with this Agreement in order to carry out its responsibilities or exercise its rights under this Agreement (including the exercise of the rights and licenses granted to the relevant Party hereunder), and (iii) in the case of either Party, to such Party’s actual or potential acquirers; provided that each such disclosee is bound by written confidentiality obligations and non-use obligations no less restrictive than those set forth in this Article 7 to maintain the confidentiality thereof and not to use such Confidential Information except as expressly permitted by this Agreement; provided, however, that, in each of the above situations in this Section 7.4.1(c), the Receiving Party shall remain responsible for any failure by any Person who receives Confidential Information from such Receiving Party pursuant to this Section 7.4.1(c) to treat such Confidential Information as required under this Article 7; and

(d)disclosure, solely on a “need to know basis” to its advisors (including attorneys and accountants) in connection with activities hereunder; provided that, prior to any such disclosure, each disclosee must be bound by written obligations of confidentiality, non-disclosure and non-use no less restrictive than the obligations set forth in this Article 7 (provided, however, that in the case of legal advisors, no written agreement shall be required), which for the avoidance of doubt, will not permit use of such Confidential Information for any purpose except those expressly permitted by this Agreement; provided, however, that, in each of the above situations in this Section 7.4.1(d), the Receiving Party shall remain responsible for any failure by any Person who receives Confidential Information from such Receiving Party pursuant to this Section 7.4.1(d) to treat such Confidential Information as required under this Article 7.

7.4.2Terms of Disclosure. If and whenever any Confidential Information is disclosed in accordance with this Section 7.4, such disclosure shall not cause any such information to cease to be Confidential Information except to the extent that such disclosure results in a public disclosure of such information (other than by breach of this Agreement). Where reasonably possible and subject to Section 7.6, the Receiving Party shall notify the Disclosing Party of the Receiving Party’s intent to make any disclosures pursuant to Section 7.4.1(a) sufficiently prior to making such disclosure so as to allow the Disclosing Party adequate time to take whatever action it may deem appropriate to protect the confidentiality of the information, and the Receiving Party will provide reasonable assistance to the Disclosing Party with respect thereto; provided that, in such event, the Receiving Party will use reasonable measures to ensure confidential treatment of such information and shall only disclose such Confidential Information of the Disclosing Party as is necessary for the purposes of Section 7.4.1(a), as applicable.

7.4.3Licensed Program Specific IP. Prothena shall not disclose the Licensed Program Specific IP without the prior written consent of Celgene, other than pursuant to Section 7.4.1

7.5Terms of this Agreement. The Parties agree that this Agreement and the terms hereof shall be deemed to be Confidential Information of both Prothena and Celgene, and each Party agrees not to disclose any of them without the prior written consent of the other Party, except that each Party may disclose any of them in accordance with the provisions of Sections 7.4 and/or 7.6, as applicable.

7.6Securities Filings; Disclosure under Applicable Law. Each Party acknowledges and agrees that the other Party may submit this Agreement to (or file this Agreement with) the SEC or any national securities exchange in any jurisdiction (collectively, the “Securities Regulators”), or to other Persons as may be required by Applicable Law, and if a Party does submit this Agreement to (or file this Agreement with) any Securities Regulators, or other Persons as may be required by Applicable Law, such Party agrees to consult with the other Party with respect to the preparation and submission of a confidential treatment request for this Agreement. Notwithstanding the foregoing, if a Party is required by Applicable Law or any Securities Regulator to make a disclosure of the terms of this Agreement in a filing or other submission as required by Applicable Law or Securities Regulator, and (a) such Party has provided copies of the disclosure to the other Party reasonably in advance of such filing or other disclosure under the circumstances, (b) such Party has promptly notified the other Party in writing of such requirement and any respective timing constraints, and (c) such Party has given the other Party a reasonable time under the circumstances from the date of notice by such Party of the required disclosure to comment upon and request confidential treatment for such disclosure, then such Party will have the right to make such disclosure at the time and in the manner reasonably determined by its counsel to be required by Applicable Law or Securities Regulator. Notwithstanding the foregoing, it is hereby understood and agreed that if a Party seeks to make a disclosure as required by Applicable Law or Securities Regulator as set forth in this Section 7.6, and the other Party provides comments within the respective time periods or constraints specified herein or within the respective notice, the Party seeking to make such disclosure or its counsel, as the case may be, will in good faith consider incorporating such comments.

7.7Publicity.

7.7.1Press Release; Public Statements. Subject to Section 7.4, 7.6 and this Section 7.7, Prothena agrees not to (and shall cause its Affiliates not to) issue any press release or other public statement disclosing this Agreement, the activities hereunder, or the transactions contemplated hereby, unless such press release or other public statement is approved by Celgene in writing; provided that Prothena shall be authorized to make any disclosure, without the approval of Celgene, that is required by Applicable Laws (including the U.S. Securities Act of 1933, as amended, and the U.S. Securities Exchange Act of 1934, as amended) or the rules of any Securities Regulator, or by judicial process, subject to and in accordance with Sections 7.4 and 7.6, as applicable. Without limiting the foregoing, and subject to the foregoing proviso, in the event that Prothena desires to issue an initial press release regarding the execution of this Agreement, Prothena shall have the right to do so provided that [***]. For the avoidance of doubt, [***].

7.7.2.Additional Restrictions on Disclosure. Without limiting any other restrictions on disclosure set forth in this Article 7, with respect to any press release or other public statement proposed to be made by Prothena, if such press release or public statement discloses, with respect to such Licensed Program, [***], such press release or other public statement may not be issued without Celgene’s prior written consent, except, for such disclosures by Prothena as required by Applicable Law or Securities Regulators (solely and to the extent Prothena’s counsel determines such disclosure is required by Applicable Law or Securities Regulators); provided that (i) in such case Prothena shall use reasonable efforts to afford Celgene a reasonable period of time to review any such disclosure and any comments made by Celgene will be considered in good faith and (ii) any information that has been previously publicly disclosed in accordance with this Agreement may be disclosed again as long as such disclosure does not exceed the scope of such prior public disclosure. Subject to the foregoing, in the event Celgene proposes that Prothena use specific wording or language with respect thereto, Prothena shall in good faith consider incorporating such wording or language.

7.7.3.Previously Issued Public Statements. The contents of any press release or other public statement that has been reviewed and approved by a reviewing Party may be re-released by the publishing Party or by such reviewing Party without a requirement for re-approval.

7.8Permitted Publications of Results.

7.8.1Publication. In the event Prothena (the “Publishing Party”) desires to publish or present any information (including publications in journals, posters, presentations at conferences and abstracts submitted in advance of conferences) with respect to the results of the Licensed Program (including the results of a Phase 1 Clinical Trial under the Licensed Program), or with respect to the Licensed Target, any Licensed Antibody or Licensed Product, the Publishing Party shall provide Celgene with a copy of such proposed publication or presentation no less than [***] days (provided that the other Party shall use Commercially Reasonable Efforts to accommodate a shorter time period if required due to circumstances outside of the Publishing Party’s control) prior to its intended submission for publication or public disclosure. For the avoidance of doubt, the foregoing shall apply with respect to each proposed publication or

presentation regardless of whether a prior publication or presentation was provided (e.g., if an abstract is provided in accordance with this Section 7.8.1 and the Publishing Party wishes to publish the corresponding full manuscript, the full manuscript must be provided to Celgene pursuant to this Section 7.8.1). Celgene shall respond in writing promptly and in no event later than [***] days after receipt of the proposed material (provided that the other Party shall use Commercially Reasonable Efforts to accommodate a shorter time period if notified by the Publishing Party and required due to circumstances outside of the Publishing Party’s control), with one or more of the following:

(a)comments on the proposed material, which the Publishing Party shall consider in good faith; and/or

(b)a specific statement of concern, based upon the need to seek patent protection or to block publication or public disclosure (including publications in journals, posters, presentations at conferences and abstracts submitted in advance of conferences) if Celgene reasonably determines that the proposed disclosure is intellectual property that should be maintained as a trade secret to protect the Licensed Target or any Licensed Antibody and/or Licensed Product, in which event the Publishing Party agrees not to submit such publication or make such presentation that contains such information until:

(i)with respect to publication or presentation of Licensed Program Non-Specific IP, Celgene is given a reasonable period of time, and in no event more than [***] days, to seek patent protection for any such Licensed Program Non-Specific IP in such publication or presentation which it believes is patentable or to resolve any other issues, or

(ii)with respect to publication or presentation of Licensed Program Specific IP, [***] for Celgene to (x) enable further development and optimization of such Licensed Program Specific IP (including related Licensed Antibodies and Licensed Products), (y) seek patent protection for any such Licensed Program Specific IP in such publication or presentation which it believes is patentable or (z) resolve any other issues; and/or

(c)an identification of Celgene’s Confidential Information that is contained in the material reviewed, which the Publishing Party shall remove, if requested by Celgene.

Notwithstanding the foregoing or anything to the contrary contained herein, the restrictions set forth in this Section 7.8.1 shall not apply to publications or presentations by Celgene (or its Affiliates or sublicensees) and Celgene (and its Affiliates and sublicensees) shall be free to make publications and presentations with respect to results of the Licensed Program, the Licensed Target, Licensed Antibody and/or Licensed Product without the prior review or consent of Prothena.

7.8.2Re-Publication; Re-Presentation. The contents of any publication or presentation that has been reviewed and approved by a reviewing Party may be re-released by the Publishing Party or the reviewing Party without a requirement for re-approval.

7.9Use of Names. Except as otherwise expressly set forth herein, no Party (or its respective Affiliates) shall use the name, trademark, trade name or logo of the other Party or its

Affiliates, or its or their respective employee(s) in any publicity, promotion, news release or other public disclosure relating to this Agreement or its subject matter, without the prior written permission of the other Party; provided that such permission shall not be required to the extent use thereof may be required by Applicable Law, including the rules of any securities exchange or market on which a Party’s (or its Affiliate’s) securities are listed or traded.

7.10Clinical Trials Registry. Celgene (and its Affiliates and designees) shall have the right to publish registry information and summaries of data and results from any Clinical Trials conducted in connection with activities under this Agreement, on its clinical trials registry or on a government-sponsored database such as www.clinicaltrials.gov, without requiring the consent of Prothena. The Parties shall reasonably cooperate if required or reasonably requested by Celgene in order to facilitate any such publication by Celgene (and its Affiliates and designees).

7.11Relationship to Master Collaboration Agreement. Except as otherwise expressly stated in this Article 7, this Agreement supersedes the provisions of Article 8 of the Master Collaboration Agreement with respect to any Confidential Information related to the Licensed Program. the Licensed Target, Licensed Antibodies or Licensed Products (the “Licensed Program Confidential Information”); provided that, except as otherwise set forth herein, all “Confidential Information” of the “Disclosing Party” thereunder that is Licensed Program Confidential Information shall be deemed Confidential Information of the Disclosing Party hereunder and shall be subject to the terms and conditions of this Agreement and the “Receiving Party” shall be bound by and obligated to comply with such terms and conditions as if they were the Receiving Party hereunder, subject in all cases to Section 7.2. The foregoing shall not be interpreted as a waiver of any remedies available to the “Disclosing Party” as a result of any breach, prior to the Effective Date, by the “Receiving Party”, of its obligations pursuant to Article 8 of the Master Collaboration Agreement.

7.12Global License Agreement. Notwithstanding the foregoing provisions of this Article 7, if a Global License Agreement is entered into with respect to the Licensed Program, then the provisions of such Global License Agreement shall control with respect to Confidential Information related to the Licensed Program in lieu of this Article 7.

ARTICLE 8
REPRESENTATIONS AND WARRANTIES; COVENANTS

8.1Representations and Warranties of Both Parties. Each Party hereby represents and warrants to the other Party, as of the Effective Date, that:

(a)such Party is duly organized, validly existing and in good standing under the Applicable Law of the jurisdiction of its formation and has full corporate power and authority to enter into this Agreement, and to carry out the provisions hereof;

(b)such Party has taken all necessary corporate action on its part to authorize the execution and delivery of this Agreement and the performance of its obligations hereunder;

(c)this Agreement has been duly executed and delivered on behalf of such Party, and constitutes a legal, valid, binding obligation, enforceable against it in accordance

with its terms, except to the extent that enforcement of the rights and remedies created hereby is subject to (i) bankruptcy, insolvency, reorganization, moratorium and other similar laws of general application affecting the rights and remedies of creditors, or (ii) laws governing specific performance, injunctive relief and other equitable remedies;

(d)the execution, delivery and performance of this Agreement by such Party does not breach or conflict with any agreement or any provision thereof, or any instrument or understanding, oral or written, to which such Party (or any of its Affiliates) is a party or by which such Party (or any of its Affiliates) is bound, nor violate any Applicable Law of any Governmental Authority having jurisdiction over such Party (or any of its Affiliates);

(e)no government authorization, consent, approval, license, exemption of or filing or registration with any court or governmental department, commission, board, bureau, agency or instrumentality, domestic or foreign, under any Applicable Law currently in effect, is or will be necessary for, or in connection with, the transaction contemplated by this Agreement, or for the performance by it of its obligations under this Agreement, except (i) as may be required to conduct Development or Commercialization activities, including conducting Clinical Trials, seeking, obtaining or maintaining Regulatory Approvals or applicable Regulatory Materials, or Manufacturing or (ii) as set forth in Section 3.2 of the Master Collaboration Agreement; and

(f)it has obtained all necessary authorizations, consents and approvals of any Third Party that is required to be obtained by it as of the Effective Date for, or in connection with, the transaction contemplated by this Agreement, or for the performance by it of its obligations under this Agreement, except (i) as may be required to conduct Development or Commercialization activities, including conducting Clinical Trials, seeking, obtaining or maintaining Regulatory Approvals or applicable Regulatory Materials, or Manufacturing or (ii) as set forth in Section 3.2 of the Master Collaboration Agreement.

8.2Representations and Warranties of Prothena. Except as set forth on Schedule 8.2 Prothena hereby represents and warrants to Celgene, as of the Effective Date, that:

(a)Schedules 1.47(b) and 1.64 contain a complete and accurate list of all Patents included in the Prothena IP that claim or cover any Licensed Target, Licensed Antibodies or Licensed Products, including the composition or use of any of the foregoing, and Prothena Controls all such Patents. Except for the Prothena IP, (i) Prothena and its Affiliates do not own or control (by license or otherwise), as of the Effective Date, any Patent or Know-How that is necessary or useful to Develop, Manufacture or Commercialize the Licensed Target, Licensed Antibodies or Licensed Products and (ii) no other Know-How or Patents arose from, or were used in, the performance of the Licensed Program under the Master Collaboration Agreement. To Prothena’s and its Affiliates’ actual knowledge, all issued Patents within the Prothena IP are in full force and effect, and are not invalid or unenforceable, in whole or in part;

(b)no claim has been issued or served, or written threat of a claim or litigation made by any Person, against Prothena or its Affiliates that alleges that any Prothena IP is invalid or unenforceable;

(c)neither Prothena nor its Affiliates own or otherwise control (through license or otherwise) any Antibodies (or any products constituting, incorporating, comprising or containing any such Antibody) that Target the Licensed Target, other than the Licensed Program Antibodies (all of which are set forth on Schedule 1.45) and the Licensed Program Products;

(d)[***];

(e)neither Prothena nor its Affiliates are subject to any payment obligations to Third Parties as a result of the execution or performance of this Agreement, or the research, development, manufacture or commercialization of the Licensed Target or any Antibodies (or any products constituting, incorporating, comprising or containing any such Antibody) that Target the Licensed Target;

(f)Prothena has the full right and authority to grant all of the rights and licenses granted to Celgene (or purported to be granted to Celgene) hereunder; and neither Prothena nor its Affiliates have granted any right or license to any Third Party relating to any of the Prothena IP or any other Licensed Program Asset, Licensed Target or Antibody (or any products constituting, incorporating, comprising or containing any such Antibody) that Targets the Licensed Target, that would conflict with [***] the rights or licenses granted to Celgene hereunder;

(g)Prothena is the sole and exclusive owner of the Prothena IP, except for the Prothena Licensed Collaboration IP that is licensed to Prothena (or its Affiliates) pursuant to the In-License Agreements set forth on Schedule 1.40. All Affiliates of Prothena have exclusively licensed or assigned all of their right, title and interest in and to the Prothena IP to Prothena. Neither Prothena nor its Affiliates have granted any mortgage, pledge, claim, security interest, lien or other charge of any kind on the Prothena IP or other Licensed Program Asset, and the Prothena IP and the other Licensed Program Assets are free and clear of any mortgage, pledge, claim, security interest, lien or charge of any kind;

(h)neither Prothena nor its Affiliates have received any written notice of any claim that any Patent or Know-How (including any trade secret right) owned or controlled by a Third Party would be infringed or misappropriated by the Development, Manufacture, or Commercialization of the Licensed Target, any Licensed Antibody or any Licensed Product;

(i)to Prothena’s and its Affiliates’ actual knowledge, (i) the Development and Manufacture of the Licensed Target, any Licensed Antibody or Licensed Product, as conducted by or on behalf of Prothena or its Affiliates prior to the Effective Date, has not violated, infringed or misappropriated any intellectual property or proprietary right of any Third Party and (ii) [***];

(j)there are no claims, judgments, settlements, litigations, suits, actions, disputes, arbitration, judicial or legal administrative or other proceedings or governmental investigations pending or, to Prothena’s or its Affiliates’ knowledge, threatened against Prothena or its Affiliates which would reasonably be expected to adversely affect or restrict the ability of Prothena to consummate or perform the transactions contemplated under this Agreement, or which would affect the Prothena IP or other Licensed Program Assets, or

Prothena’s Control thereof, or the Licensed Target or any Licensed Antibody or Licensed Product;

(k)neither Prothena nor its Affiliates have issued a claim against a Third Party alleging that a Third Party is infringing or has infringed or misappropriated any Prothena IP, and, to Prothena’s and its Affiliates’ actual knowledge, no issued Patents within the Prothena IP are being infringed and no trade secrets within the Prothena IP are being misappropriated by any Third Party;

(l)neither Prothena nor its Affiliates have employed or otherwise used in any capacity, the services of any Person suspended, proposed for debarment or debarred under United States law, including under 21 U.S.C. § 335a, or any foreign equivalent thereof, with respect to the Licensed Target, the Licensed Antibodies or Licensed Products or otherwise in performing any portion of the Licensed Program. All Manufacture and Development (including non-clinical studies and Clinical Studies) related to the Licensed Target, Licensed Antibodies or Licensed Products conducted by or on behalf of Prothena or its Affiliates prior to the Effective Date (including the conduct of the Licensed Program under the Master Collaboration Agreement) has been conducted in accordance with all Applicable Laws (including, to the extent applicable, GCP, GLP and GMP);

(m)neither Prothena nor its Affiliates have entered into any agreement under which Prothena or its Affiliates (i) has obtained a license or sublicense of rights from a Third Party to the Licensed Target, or to any Antibodies (or any products constituting, incorporating, comprising or containing any such Antibody) that Target the Licensed Target, or to any Prothena IP, except for the In-License Agreements set forth on Schedule 1.40, or (ii) has granted a license, sublicense, option or right to a Third Party that remains in effect as of the Effective Date to research, develop, manufacture or commercialize the Licensed Target or any Antibodies (or any products constituting, incorporating, comprising or containing any such Antibody) that Target the Licensed Target, except (1) with respect to licenses or rights granted pursuant to the agreements set forth on Schedule 1.40 that were entered into in the ordinary course of business [***] and (2) with respect to [***]. The agreements set forth on Schedule 1.40 do not conflict with [***] the rights or licenses granted to Celgene hereunder;

(n)other than the Existing Program Agreements, Prothena (or its Affiliates, as applicable) has not entered into any agreement relating to the Development, Manufacture, Commercialization or other exploitation of the Licensed Target, Licensed Antibodies or Licensed Products, or the Prothena IP;

(o)with respect to each Existing Program Agreement and In-License Agreement, (i) it is in full force and effect; (ii) Prothena (or its Affiliate, as applicable) is not in breach thereof; (iii) Prothena (or its Affiliate, as applicable) has not received any notice from the counterparty to such Existing Program Agreement or In-License Agreement, as applicable, of Prothena’s (or its Affiliate’s, as applicable) breach or notice of threatened breach by Prothena (or its Affiliate, as applicable) thereof and (iv) Prothena has provided Celgene with [***] copy of each Existing Program Agreement and In-License Agreement;

(p)Prothena has disclosed to Celgene all material information and data, and all material correspondences to/from any Regulatory Authority, existing as at the Effective Date in the possession or control of Prothena or its Affiliates, in each case related to the Licensed Program, Licensed Target, Licensed Antibodies or Licensed Products; and

(q)Prothena has not obtained, or filed, any INDs, MAAs or Regulatory Approvals or any other form of regulatory application for approval of Clinical Trials, marketing or other purpose, for any Licensed Antibodies or Licensed Products and, to Prothena’s and its Affiliates’ actual knowledge, no other Person has obtained, or filed for, any such INDs, MAAs or Regulatory Approvals.

8.3Additional Representations, Warranties and Covenants of Prothena. Prothena hereby further represents, warrants and covenants to Celgene that:

8.3.1.With respect to the In-License Agreements, (a) Prothena (or its Affiliates, as applicable) shall not breach, or commit any acts or permit the occurrence of any omissions that would cause the breach or termination, of any In-License Agreement and (b) Prothena shall (or shall cause its Affiliates to, as applicable) satisfy all of its obligations under each In-License Agreement in all material respects and shall, or shall cause its Affiliates to, as applicable, maintain each In-License Agreement in full force and effect. Prothena shall, or shall cause its Affiliates to, as applicable, enforce its rights under each In-License Agreement to the extent necessary to preserve Celgene’s rights under this Agreement. Prothena shall not, and shall cause its Affiliates not to [***] if doing so [***]. Prothena will provide Celgene with prompt written notice of any claim of a breach of which it is aware under any of the In-License Agreements or notice of termination of any In-License Agreement.

8.3.2.With respect to the Existing Program Agreements, (a) Prothena (or its Affiliates, as applicable) shall not breach, or commit any acts or permit the occurrence of any omissions that would cause the breach or termination, of any Existing Program Agreement and (b) Prothena shall (or shall cause its Affiliates to, as applicable) satisfy all of its obligations under each Existing Program Agreement in all material respects and shall, or shall cause its Affiliates to, as applicable, maintain each Existing Program Agreement in full force and effect, unless Prothena otherwise obtains Celgene’s prior written consent (such consent not to be unreasonably withheld). Prothena shall, or shall cause its Affiliates to, as applicable, enforce its rights under each Existing Program Agreement to the extent necessary to preserve Celgene’s rights under this Agreement. Prothena shall not, and shall cause its Affiliates not to [***]. Prothena shall not, and shall cause its Affiliates not to assign or otherwise transfer any Existing Program Agreement. Prothena will provide Celgene with prompt written notice of any claim of a breach of which it is aware under any of the Existing Program Agreements or notice of termination of any Existing Program Agreement.

8.3.3.In-License Agreements. At the written request of Celgene on case-by-case basis, Prothena shall (or shall cause its Affiliates to, as applicable) execute a written agreement, in a form reasonably acceptable to Celgene, with each Third Party that is a counterparty to the applicable In-License Agreement (each such counterparty, a “Prothena Licensor”) within [***] days after the date of such request, pursuant to which (a) in the event of an early termination of such In-License Agreement [***], on the same terms under which such Prothena Licensor grants

such license to Prothena (or its Affiliate, as applicable) under such In-License Agreement, (b) such Prothena Licensor [***].

8.3.4.Notwithstanding anything to the contrary contained herein, in the event that Celgene (or any of its Affiliates) obtains a license to any Patents, Know-How or other intellectual property from any Prothena Licensor, then Celgene [***].

8.3.5.Prothena shall promptly notify Celgene in writing if any Patents in the Prothena IP that claim or cover any Licensed Target, Licensed Antibodies or Licensed Products, including the composition or use of any of the foregoing, becomes known to Prothena that are not listed on Schedule 1.47(b) or 1.64.

8.4Representations and Warranties of Celgene. Except as set forth on Schedule 8.4, Celgene hereby represents and warrants to Prothena, as of the Effective Date, that:

8.4.1there are no claims, judgments, settlements, litigations, suits, actions, disputes, arbitration, judicial or legal administrative or other proceedings or governmental investigations pending or, to Celgene’s actual knowledge, threatened against Celgene which would reasonably be expected to adversely affect or restrict the ability of Celgene to consummate or perform the transactions contemplated under this Agreement.

8.5Covenants.

8.5.1Mutual Covenants. Each Party hereby covenants to the other Party that:

(a)such Party and its Affiliates shall perform its activities pursuant to this Agreement in compliance (and shall ensure compliance by any of its subcontractors) with all Applicable Laws, including, to the extent applicable, GCP, GLP and GMP; and

(b)such Party and its Affiliates shall not employ or otherwise use in any capacity the services of any Person suspended, proposed for debarment or debarred under United States law, including under 21 U.S.C. § 335a, or any foreign equivalent thereof, with respect to the Licensed Target, the Licensed Antibodies or Licensed Products or in performing any activities, including Development Activities, under this Agreement. All Manufacture and Development (including non-clinical studies and Clinical Trials) related to the Licensed Target, Licensed Antibodies or Licensed Products conducted by or on behalf of each Party or its Affiliates under this Agreement after the Effective Date (including the conduct of Manufacturing for Clinical Trials) shall be conducted in accordance with all Applicable Laws (including, to the extent applicable, GCP, GLP and GMP)

8.5.2Prothena Covenants. Prothena hereby covenants to Celgene that:

(a)Neither Prothena nor its Affiliates shall grant any right or license to any Third Party relating to any of the intellectual property rights it owns or Controls (including the Prothena IP and other Licensed Program Assets), or otherwise with respect to any Licensed Antibody, Licensed Product or Diagnostic Product which conflict with, [***] any of the rights or licenses granted to Celgene hereunder; and

(b)Except with respect to the performance of the Prothena Ongoing Program Activities in accordance with Section 2.3 (or as otherwise expressly agreed to by Celgene in writing, including as set forth in Section 2.7), neither Prothena nor its Affiliates shall use (and neither shall grant any Third Party the right to use) any Licensed Antibodies, Licensed Products or Diagnostic Products for any purposes in the Territory.

8.6Disclaimer. EXCEPT AS OTHERWISE EXPRESSLY PROVIDED IN THIS AGREEMENT, NEITHER PARTY MAKES ANY REPRESENTATIONS OR EXTENDS ANY WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED (AND EACH PARTY HEREBY EXPRESSLY DISCLAIMS ANY AND ALL REPRESENTATIONS AND WARRANTIES NOT EXPRESSLY PROVIDED IN THIS AGREEMENT), INCLUDING WITH RESPECT TO ANY PATENTS OR KNOW-HOW, OR MATERIALS, INCLUDING WARRANTIES OF VALIDITY OR ENFORCEABILITY, MERCHANTABILITY, FITNESS FOR A PARTICULAR USE OR PURPOSE, PERFORMANCE, AND NONINFRINGEMENT OF ANY THIRD PARTY PATENTS OR OTHER INTELLECTUAL PROPERTY RIGHTS. WITHOUT LIMITING THE FOREGOING, NEITHER PARTY MAKES ANY REPRESENTATION, WARRANTY OR GUARANTEE THAT THE LICENSED PROGRAM WILL BE SUCCESSFUL, OR THAT ANY OTHER PARTICULAR RESULTS WILL BE ACHIEVED WITH RESPECT TO THE LICENSED PROGRAM, THE LICENSED TARGET, ANY LICENSED ANTIBODY OR ANY LICENSED PRODUCT HEREUNDER.

ARTICLE 9
INDEMNIFICATION; INSURANCE

9.1Indemnification by Celgene. Celgene shall indemnify, defend and hold harmless Prothena and its Affiliates and its and their respective directors, officers, employees, agents, successors and assigns (collectively, the “Prothena Indemnitees”), from and against any and all Third Party Damages to the extent arising out of or relating to, directly or indirectly, any Third Party Claim based upon:

(a)the gross negligence or willful misconduct of Celgene or its Affiliates or its or their respective directors, officers, employees or agents, in connection with Celgene’s performance of its obligations under this Agreement;

(b)any breach by Celgene of any of its representations, warranties, covenants, agreements or obligations under this Agreement; or

(c)any claim for personal injury or death arising out of the Development, Manufacture or Commercialization of the Licensed Antibodies and Licensed Products in the Territory by or on behalf of Celgene or its Affiliates or Sublicensees during the Term;

in each case (a)-(c), provided, however, that such indemnity shall not apply to the extent Prothena has an indemnification obligation pursuant to Section 9.2(a) or (b) for such Third Party Damages.

9.2Indemnification by Prothena. Prothena shall indemnify, defend and hold harmless Celgene, its Affiliates and its and their respective directors, officers, employees, agents,

successors and assigns (collectively, the “Celgene Indemnitees”), from and against any and all Third Party Damages to the extent arising out of or relating to, directly or indirectly, any Third Party Claim based upon:

(a)the gross negligence or willful misconduct of Prothena or its Affiliates or its or their respective directors, officers, employees or agents, in connection with Prothena’s performance of its obligations under this Agreement;

(b)any breach by Prothena of any of its representations, warranties, covenants, agreements or obligations under this Agreement; or

(c)any claim for personal injury or death arising out of the Development, Manufacture or Commercialization of the Licensed Antibodies (including Reversion Antibodies) and Licensed Products (including products containing Reversion Antibodies) by or on behalf of Prothena or its Affiliates or sublicensees;

in each case (a)-(c), provided, however, that such indemnity shall not apply to the extent Celgene has an indemnification obligation pursuant to Section 9.1(a) or (b) for such Third Party Damages.

9.3Procedure. If a Party is seeking indemnification under Section 9.1 or 9.2, as applicable (the “Indemnitee”), it shall inform the other Party (the “Indemnitor”) of the claim giving rise to the obligation to indemnify pursuant to Section 9.1 or 9.2, as applicable, as soon as reasonably practicable after receiving notice of the claim (provided, however, any delay or failure to provide such notice shall not constitute a waiver or release of, or otherwise limit, the Indemnitee’s rights to indemnification under Section 9.1 or 9.2, as applicable, except to the extent that such delay or failure materially prejudices the Indemnitor’s ability to defend against the relevant claims). The Indemnitor shall have the right to assume the defense of any such claim for which the Indemnitee is seeking indemnification pursuant to Section 9.1 or 9.2, as applicable. The Indemnitee shall cooperate with the Indemnitor and the Indemnitor’s insurer as the Indemnitor may reasonably request, and at the Indemnitor’s cost and expense. The Indemnitee shall have the right to participate, at its own expense and with counsel of its choice, in the defense of any claim or suit that has been assumed by the Indemnitor. The Indemnitor shall not settle any claim without the prior written consent of the Indemnitee, not to be unreasonably withheld; provided, however, that the Indemnitor shall not be required to obtain such consent if the settlement (i) involves only the payment of money and will not result in the Indemnitee (or other Prothena Indemnitees or Celgene Indemnitees, as applicable) becoming subject to injunctive or other similar type of relief, (ii) does not require an admission by the Indemnitee (or other Prothena Indemnitees or Celgene Indemnitees, as applicable) and (iii) does not adversely affect the rights or licenses granted to the Indemnitee (or its Affiliate) under this Agreement. The Indemnitee shall not settle or compromise any such claim without the prior written consent of the Indemnitor, which it may provide in its sole discretion. If the Parties cannot agree as to the application of Section 9.1 or 9.2, as applicable, to any claim, pending resolution of the dispute pursuant to Section 11.8 the Parties may conduct separate defenses of such claims, with each Party retaining the right to claim indemnification from the other Party in accordance with Section 9.1 or 9.2, as applicable, upon resolution of the underlying claim. In each case, the Indemnitee shall reasonably cooperate with the Indemnitor, and shall make available to the Indemnitor all

pertinent information under the control of the Indemnitee, which information shall be subject to Article 7.

9.4Insurance. During the Term and for a period of [***] years thereafter, each Party shall maintain, at its cost, a program of insurance and/or self-insurance against liability and other risks associated with its activities and obligations under this Agreement (including, with respect to its Clinical Trials), and its indemnification obligations hereunder, in such amounts, subject to such deductibles and on such terms as are customary for such Party for the activities to be conducted by it under this Agreement. It is understood that such insurance shall not be construed to create a limit on either Party’s liability with respect to its indemnification obligations under this Article 9, or otherwise.

9.5LIMITATION OF LIABILITY. NEITHER PROTHENA NOR CELGENE, NOR ANY OF THEIR RESPECTIVE AFFILIATES, WILL BE LIABLE TO THE OTHER PARTY OR ITS AFFILIATES UNDER OR IN CONNECTION WITH THIS AGREEMENT FOR ANY INDIRECT, INCIDENTAL, CONSEQUENTIAL, SPECIAL OR PUNITIVE OR EXEMPLARY DAMAGES (INCLUDING LOST PROFITS OR LOST REVENUES), WHETHER LIABILITY IS ASSERTED IN CONTRACT, TORT (INCLUDING NEGLIGENCE AND STRICT PRODUCT LIABILITY), INDEMNITY, CONTRIBUTION OR OTHERWISE, AND IRRESPECTIVE OF WHETHER THAT PARTY OR ANY REPRESENTATIVE OF THAT PARTY HAS BEEN ADVISED OF, OR OTHERWISE MIGHT HAVE ANTICIPATED THE POSSIBILITY OF, ANY SUCH LOSS OR DAMAGE. NOTWITHSTANDING THE FOREGOING, NOTHING IN THIS SECTION 9.5 IS INTENDED TO OR SHALL LIMIT OR RESTRICT THE INDEMNIFICATION RIGHTS OR OBLIGATIONS OF ANY PARTY UNDER SECTIONS 9.1 OR 9.2 IN CONNECTION WITH ANY THIRD PARTY CLAIMS[***].

ARTICLE 10
TERM AND TERMINATION

10.1Term; Expiration.

10.1.1Term. Subject to Section 3.2 of the Master Collaboration Agreement, this Agreement shall become effective on the Effective Date and, unless earlier terminated in accordance with this Article 10, shall remain in effect until it expires as follows (the “Term”):

(a)on a Licensed Product-by-Licensed Product basis, this Agreement shall expire on the date of the expiration of the Royalty Term with respect to such Licensed Product; and

(b)in its entirety upon the expiration of all applicable Royalty Terms under this Agreement with respect to all Licensed Products in the Territory.

10.1.2Effect of Expiration. After the expiration of the Term pursuant to Section 10.1.1 above, the following terms shall apply:

(a)Licenses after Licensed Product Expiration. After expiration of the Term with respect to a given Licensed Product pursuant to Section 10.1.1(a), the licenses set

forth in Section 6.1 with respect to such Licensed Product (and the Licensed Antibody contained therein) and related Diagnostic Products will automatically become fully paid-up, perpetual, irrevocable and royalty-free.

(b)Licenses after Expiration of Agreement. After expiration of the Term with respect to this Agreement in its entirety pursuant to Section 10.1.1(b), all licenses set forth in Section 6.1 will automatically become fully paid-up, perpetual, irrevocable and royalty-free.

10.2Termination for Breach.

10.2.1Material Breach. This Agreement may be terminated by a Party for the material breach by the other Party of this Agreement provided that the breaching Party has not cured such breach within ninety (90) days after the date of written notice to the breaching Party of such breach (or thirty (30) days in the case of a breach as a result of non-payment of any amounts due under this Agreement) (the “Cure Period”), which notice shall describe such breach in reasonable detail and shall state the non-breaching Party’s intention to terminate this Agreement. For clarity, but subject to Section 10.2.2, the Cure Period for any allegation made as to a material breach under this Agreement will run from the date that written notice was first provided to the breaching Party by the non-breaching Party. Any such termination of this Agreement under this Section 10.2.1 shall become effective at the end of the Cure Period, unless the breaching Party has cured such breach prior to the expiration of such Cure Period, or, if such breach is not susceptible to cure within the Cure Period, then such Cure Period shall be extended for an additional [***] days so long as the breaching Party continues to use commercially reasonable efforts to cure such material breach during such extension period. For the avoidance of doubt, termination of this Agreement pursuant to this Section 10.2.1 shall terminate the Master Collaboration Agreement solely with respect to the Licensed Program but shall not terminate the Master Collaboration Agreement with respect to any other Programs or any other U.S. License Agreement or Global License Agreement for any other Program.

10.2.2Disagreement as to Material Breach. Notwithstanding Section 10.2.1, if the Parties in good faith disagree as to whether there has been a material breach of this Agreement pursuant to Section 10.2.1, then: (a) the Party that disputes that there has been a material breach may contest the allegation by referring such matter, within [***] days following such notice of alleged material breach, for resolution to the Executive Officers, who shall meet promptly to discuss the matter and determine, within [***] Business Days following referral of such matter, whether or not a material breach has occurred pursuant to Section 10.2.1; provided that if the Executive Officers are unable to resolve such dispute within such [***] Business Day period after it is referred to them, the matter will be resolved as provided in Section 11.8; (b) the relevant Cure Period with respect thereto will be tolled from the date the breaching Party notifies the non-breaching Party of such dispute and through the resolution of such dispute in accordance with the applicable provisions of this Agreement; (c) subject to Section 10.12, during the pendency of such dispute, all of the terms and conditions of this Agreement shall remain in effect and the Parties shall continue to perform all of their respective obligations hereunder; and (d) if it is ultimately determined that the breaching Party committed such material breach, then the breaching Party shall have the right to cure such material breach, after such determination, within

the Cure Period (as may be extended in accordance with Section 10.2.1) which shall commence as of the date of such determination.

10.3Voluntary Termination. Celgene may terminate this Agreement at will, in its sole discretion, in its entirety upon sixty (60) days’ prior written notice to Prothena at any time.

10.4Termination for Bankruptcy. If either Party makes a general assignment for the benefit of, or an arrangement or composition generally with, its creditors, appoints or suffers appointment of an examiner or of a receiver or trustee over all or substantially all of its property, passes a resolution for its winding up or files a petition under any bankruptcy or insolvency act or law or has any such petition filed against it which is not dismissed, discharged, bonded or stayed within ninety (90) days after the filing thereof (each, an “Insolvency Event”), the other Party may terminate this Agreement in its entirety, effective immediately upon written notice to such Party, provided that, in connection therewith, the provisions of Section 6.5 shall apply.

10.5Termination for Failure to Commence Preliminary Activities in Support of Clinical Trial. In the event that (i) Celgene does not exercise its Phase 1 Option for the Licensed Program in accordance with the Master Collaboration Agreement prior to the end of the Phase 1 Option Term for the Licensed Program and (ii) Celgene (or its Affiliates or Sublicensees) does not, within [***] months after the end of the Phase 1 Option Term for the Licensed Program (the “Clinical Trial Preliminary Activities Outside Date”), engage in any activities in support of an IND for a Clinical Trial for a Licensed Product, then Prothena may terminate this Agreement in its entirety upon [***] days’ prior written notice to Celgene; provided that such termination notice is provided within [***] days after the Clinical Trial Preliminary Activities Outside Date. Notwithstanding the foregoing, the Clinical Trial Preliminary Activities Outside Date shall be automatically extended by one day for each day that Celgene (or its Affiliates or Sublicensees, as applicable) is delayed from engaging in activities in support of the commencement of a Clinical Trial for a Licensed Product caused by [***], including delays caused by Regulatory Authorities (including regulatory or clinical hold).

10.6Termination for Patent Challenge. Prothena shall have the right to terminate this Agreement upon written notice if Celgene or any Affiliate of Celgene challenges the validity, scope or enforceability of or otherwise opposes any Patent included in the Prothena IP that is licensed to Celgene under this Agreement, in each case through a formal proceeding (other than as may be necessary or reasonably required to assert a cross-claim or a counter-claim or to respond to a court request or order or administrative law, request or order). If a Sublicensee of Celgene with respect to any Prothena IP challenges the validity, scope or enforceability of or otherwise opposes any Patent included in such Prothena IP under which such Sublicensee is sublicensed in each case through a formal proceeding (other than as may be necessary or reasonably required to assert a cross-claim or a counter-claim or to respond to a court request or order or administrative law, request or order), then Celgene shall, upon written notice from Prothena, terminate such sublicense.

10.7Termination Upon Execution of Global License Agreement for Licensed Program. This Agreement shall automatically terminate if the Parties (or their respective Affiliates, as applicable) enter into a Global License Agreement for the Licensed Program in accordance with the terms of the Master Collaboration Agreement.

10.8Effects of Expiration or Termination; Additional Remedies.

10.8.1Termination by Prothena Pursuant to Section 10.2, 10.4, 10.5 or 10.6, or by Celgene Pursuant to Section 10.3 or Section 10.14. In the event this Agreement is terminated by Prothena pursuant to Section 10.2, 10.4 ,10.5 or 10.6, or by Celgene pursuant to Section 10.3, upon the effective date of such termination:

(a)the Master Collaboration Agreement (if not previously expired or terminated) shall also terminate automatically with respect to the Licensed Program (but not any other Program);

(b)except as set forth in this Section 10.8.1 or Sections 10.10 or 10.11, all rights and licenses granted herein shall terminate;

(c)any and all Collaboration Specific IP shall thereafter no longer be deemed to be Collaboration Specific IP;

(d)each Party shall return or destroy all Confidential Information of the other Party as required by Article 7; and

(e)notwithstanding the foregoing provisions of this Section 10.8.1, the licenses granted to Celgene hereunder shall survive for [***] months following the effective date of termination in order for Celgene (and its Affiliates, Sublicensees and distributors), at Celgene’s discretion, during the [***] month period immediately following the effective date of termination, to (i) finish or otherwise wind-down any ongoing Clinical Trials with respect to any Licensed Antibodies, Licensed Products or Diagnostic Products hereunder and (ii) finish and sell any work-in-progress and any Licensed Antibodies, Licensed Products or Diagnostic Products remaining in inventory (provided that Celgene shall pay royalties on Annual Net Sales of such Licensed Products sold by Celgene during such period (provided that the applicable Royalty Term is still ongoing) as an to the extent Celgene would otherwise be required to pay such royalties as set forth in Section 5.2); provided that, for clarity, Celgene shall have no obligation to undertake such activities, in each case of (i) and (ii), as and to the extent determined by Celgene.

10.8.2Termination by Celgene Pursuant to Section 10.2 or 10.4. In the event this Agreement is terminated by Celgene pursuant to Section 10.2 or 10.4, upon the effective date of such termination:

(a)the Master Collaboration Agreement (if not previously expired or terminated) shall also terminate automatically with respect to the Licensed Program (but not any other Program);

(b)except as set forth in this Section 10.8.2 or Sections 10.10 or 10.11, all rights and licenses granted herein shall terminate;

(c)any and all Collaboration Specific IP hall thereafter no longer be deemed to be Collaboration Specific IP;

(d)each Party shall return or destroy all Confidential Information of the other Party as required by Article 7; and

(e)notwithstanding the foregoing provisions of this Section 10.8.2, the licenses granted to Celgene hereunder shall survive for [***] months following the effective date of termination in order for Celgene (and its Affiliates, Sublicensees and distributors), at Celgene’s discretion, during the [***] month period immediately following the effective date of termination, to (i) finish or otherwise wind-down any ongoing Clinical Trials with respect to any Licensed Antibodies, Licensed Products or Diagnostic Products hereunder and (ii) finish and sell any work-in-progress and any Licensed Antibodies, Licensed Products or Diagnostic Products remaining in inventory (provided that Celgene shall pay royalties on Annual Net Sales of such Licensed Products sold by Celgene during such period (provided that the applicable Royalty Term is still ongoing) as an to the extent Celgene would otherwise be required to pay such royalties as set forth in Section 5.2); provided that, for clarity, Celgene shall have no obligation to undertake such activities, in each case of (i) and (ii), as and to the extent determined by Celgene.

10.8.3Termination Pursuant to Section 10.7. In the event this Agreement is terminated pursuant to Section 10.7, upon the effective date of such termination, except as set forth in Section 10.11, all rights and licenses granted herein shall terminate.

10.9Certain Additional Remedies of Celgene in Lieu of Termination. In the event that (i) Celgene notifies Prothena in writing of a material breach of this Agreement by Prothena, and (ii) Celgene would have the right to terminate this Agreement pursuant to Section 10.2, then in lieu of Celgene terminating pursuant to Section 10.2, and without limiting any other rights or remedies of Celgene, Celgene may elect to have this Agreement continue in full force and effect by providing written notice thereof to Prothena; provided, however, that if Celgene so elects to continue this Agreement, [***].

10.10Prothena Reversion Antibodies. If this Agreement terminates, except for any termination by Celgene pursuant to Section 10.2 or 10.4 or termination pursuant to Section 10.7, then the provisions of this Section 10.10 (and for the avoidance of doubt, the provisions of this Section 10.10 shall not apply in the case of termination by Celgene pursuant to Section 10.2 or 10.4 or termination pursuant to Section 10.7).

10.10.1Reversion. All Licensed Program Antibodies that were the subject of Clinical Trials conducted by Celgene pursuant to this Agreement shall be automatically and immediately deemed “Prothena Reversion Antibodies”. Celgene shall grant and hereby grants to Prothena a non-exclusive, royalty-free, license in the Territory, with the right to grant sublicenses through multiple tiers, under any Patents and/or Know-How Controlled by Celgene or its Affiliates as of the termination effective date claiming or covering the constituting inventions that were actually incorporated by Celgene, pursuant to its activities hereunder during the Term, into the Prothena Reversion Antibodies as they exist as of such termination effective date, solely as necessary to research, Develop, Manufacture, use, import, offer for sale, sell, and Commercialize Prothena Reversion Antibodies (as they exist as of such termination effective date) in the Field in the Territory; [***].

10.10.2Effects of Reversion. With respect to each Prothena Reversion Antibody:

(a)Except to the extent not permitted pursuant to any agreements between Celgene and a Third Party, Celgene shall provide to Prothena, within a reasonable time, at Prothena’s request (provided that such request was made within [***] days after the effective date of termination), subject to [***], copies of (i) [***] Clinical Trial data and results generated by or on behalf of Celgene or its Affiliates in the Development of Prothena Reversion Antibodies pursuant to this Agreement, and (ii) [***] relating to the manufacture of such Prothena Reversion Antibodies; in each case, to the extent in Celgene’s possession as of the termination effective date [***]. For clarity, Prothena shall have the right to use the foregoing [***] solely in connection with the exercise of Prothena’s rights under Section 10.10.1;

(b)Celgene shall transfer within a reasonable time to Prothena, at Prothena’s request (provided that such request was made within [***] after the effective date of termination), and [***], [***] Regulatory Filings in the Territory [***] for the Prothena Reversion Antibodies [***] by Celgene or its Affiliates as of the termination effective date; [***];

(c)Celgene shall otherwise cooperate reasonably with Prothena to provide a transfer of the materials described in the foregoing provisions of this Section 10.10.2, [***];

(d)As and to the extent a Third Party is Manufacturing such Prothena Reversion Antibody for Celgene or its Affiliate, Celgene shall use reasonable efforts, at Prothena’s request (provided that such request was made within [***] days after the effective date of termination) [***], to [***]. Additionally, at Prothena’s request (provided that such request was made within [***] days after the effective date of termination), Celgene shall transfer to Prothena [***] supplies of such Prothena Reversion Antibody [***] by Celgene and then in Celgene’s possession, for a price equal to Celgene’s [***];

(e)To the extent that Celgene or its Affiliate owns any trademark(s) and/or domain names that [***] a Prothena Reversion Antibody in the Territory that [***] for the Commercialization of a Prothena Reversion Antibody (as then [***], but not including any marks that include, in whole or part, any corporate name or logo of Celgene or its Affiliate), Prothena shall have the right to [***]. Prothena shall exercise such right by written notice to Celgene within [***] days after such Licensed Antibody or Licensed Product becomes a Prothena Reversion Antibody; and

(f)If Celgene or its Affiliate has obtained a license from a Third Party and Prothena is a sublicensee under such license pursuant to Section 10.10.1, then Prothena [***]. Notwithstanding the provisions of Section 10.10.1, Prothena shall not get a sublicense of any Third Party intellectual property pursuant to Section 10.10.1 unless such sublicense is allowed pursuant to and in accordance with the agreement between Celgene and such Third Party.

10.11Surviving Provisions.

10.11.1Accrued Rights; Remedies. Termination or expiration of this Agreement for any reason shall be without prejudice to any rights that shall have accrued to the benefit of any Party prior to such termination or expiration, and any and all damages or remedies (whether in law or in equity) arising from any breach hereunder, each of which shall survive termination or expiration of this Agreement. Such termination or expiration shall not relieve any Party from obligations which are expressly indicated to survive termination or expiration of this Agreement. Except as otherwise expressly set forth in this Agreement, the termination provisions of this Article 10 are in addition to any other relief and remedies available to either Party under this Agreement and at Applicable Law.

10.11.2Survival. Without limiting the provisions of Section 10.11.1, the rights and obligations of the Parties set forth in the following Sections and Articles of this Agreement shall survive the expiration or termination of this Agreement, in addition to those other terms and conditions that are expressly stated to survive termination or expiration of this Agreement: ARTICLE 1 (to the extent the definitions are used in other surviving provisions), Section 2.2.4 (in the case of expiration only), Section 2.2.5 (in the case of expiration only), ARTICLE 5 (as to payment obligations accrued prior to the effectiveness of termination or expiration of this Agreement), Section 6.3, Section 6.4, Section 6.5, Section 6.6, Section 6.12 (solely if there is no other U.S. License Agreement or Global License Agreement covering the applicable Joint Patents), ARTICLE 7, Section 8.6, ARTICLE 9, Section 10.1.2, Section 10.8, Section 10.9, Section 10.10, Section 10.11, Section 10.12, Section 10.13, Section 10.14 and ARTICLE 11.

10.12Milestone Payments. Notwithstanding anything to the contrary contained herein, in the event notice of termination of this Agreement is given prior to achievement of a given milestone set forth in Section 5.3 or 5.4, Celgene shall not be obligated to make any Regulatory Milestone Payment or Sales Milestone Payment to Prothena with respect to any milestone achieved following the notice of such termination.

10.13Relationship to Other Agreements. Termination of this Agreement shall not affect in any way the terms or provisions of any other then-existing executed U.S. License Agreements or Global License Agreements.

10.14Termination by [***] for Safety Reason. Either Party may suspend conduct of any Development activity delegated to a Party hereunder, and [***] further may terminate this Agreement on a Licensed Antibody-by-Licensed Antibody or Licensed Product-by-Licensed Product basis upon written notice to the other Party based on a Safety Reason. In the Event of such suspension or notice of termination for a Safety Reason, prior to the suspending or terminating Party providing written notice, each Party’s safety committee shall, to the extent practicable, meet and discuss in good faith the safety concerns raised by the suspending or terminating Party and consider in good faith the input, questions and advice of the non-suspending or non-terminating Party. The Party suspending the conduct of a Development activity for a Safety Reason shall be responsible, at its expense, for the suspension, and [***], for the wind-down of any Development of the applicable Licensed Antibody or Licensed Product (including any Clinical Trials for the applicable Licensed Product being conducted by or on behalf of [***]) and any Commercialization activities for the applicable Licensed Product. In the

event of a termination under this Section 10.14, such termination shall become effective upon the date that [***] notifies [***] in writing that such wind-down is complete. [***] Notwithstanding anything to the contrary in this Agreement [***]. For clarity, the Parties acknowledge and agree that, notwithstanding the terms set forth in the Form of U.S. License Agreement and Form of Global License Agreement attached to the Master Collaboration Agreement, any U.S. License Agreements and Global License Agreements entered into following the date hereof shall reflect the terms and conditions agreed upon in this Section 10.14.

ARTICLE 11
MISCELLANEOUS

11.1Severability. If any one or more of the terms or provisions of this Agreement is held by a court of competent jurisdiction to be void, invalid or unenforceable in any situation in any jurisdiction, such holding shall not affect the validity or enforceability of the remaining terms and provisions hereof or the validity or enforceability of the invalid, void or unenforceable term or provision in any other situation or in any other jurisdiction, and the term or provision shall be considered severed from this Agreement solely for such situation and solely in such jurisdiction. If the final judgment of such court declares that any term or provision hereof is invalid, void or unenforceable, the Parties agree to (a) reduce the scope, duration, area or applicability of the term or provision or to delete specific words or phrases to the minimum extent necessary to cause such term or provision as so reduced or amended to be enforceable, and (b) make a good faith effort to replace any invalid, void or unenforceable term or provision with a valid and enforceable one such that the objectives contemplated by the Parties when entering this Agreement may be realized.

11.2Notices. Any notice required or permitted to be given by this Agreement shall be in writing and in English and shall be (a) delivered by hand or by overnight courier with tracking capabilities, (b) mailed postage prepaid by first class, registered, or certified mail, or (c) delivered by facsimile followed by delivery via either of the methods set forth in Sections 11.2(a) and (b), in each case, addressed as set forth below unless changed by notice so given:

If to Celgene:

Celgene Switzerland LLC

c/o Bristol-Myers Squibb Company

430 East 29th Street

14th Floor, NY, NY 10016

Attention: [***]

With copies to:

Bristol-Myers Squibb Company

Route 206 and Province Line Road

Princeton, NJ 08543-4000

Attention: Executive Vice President, Strategy & Business Development

and

Bristol-Myers Squibb Company

Route 206 and Province Line Road

Princeton, NJ 08543-4000

Attention: Senior Vice President and Associate General Counsel, Transactions Law

If to Prothena:

Prothena Biosciences Limited
77 Sir John Rogerson’s Quay, Block C
Grand Canal Docklands, Dublin 2, D02 VK60
Ireland
Attention: Company Secretary

With copies to:

Prothena Biosciences Inc.

331 Oyster Point Boulevard
South San Francisco, CA, 94080

U.S.A.
Attention: Legal Department

Any such notice shall be deemed given on the date received, except any notice received after 5:30 p.m. (in the time zone of the receiving party) on a Business Day or received on a non-Business Day shall be deemed to have been received on the next Business Day. A Party may add, delete, or change the person or address to which notices should be sent at any time upon written notice delivered to the other Parties in accordance with this Section 11.2.

11.3Force Majeure. A Party shall not be liable for delay or failure in the performance of any of its obligations hereunder if such delay or failure is due to a cause beyond the reasonable control of such Party, including acts of God, fires, earthquakes, epidemics, pandemics (provided, however, that the Parties [***], acts of war, terrorism, or civil unrest, or hurricane or other inclement weather (“Force Majeure”); provided, however, that the affected Party promptly notifies the other Party and further provided that the affected Party shall use its commercially reasonable efforts to avoid or remove such causes of non-performance and to mitigate the effect of such occurrence, and shall continue performance in accordance with the terms of this Agreement whenever such causes are removed. When such circumstances arise, the Parties shall negotiate in good faith any modifications of the terms of this Agreement that may be necessary or appropriate in order to arrive at an equitable solution.

11.4Assignment.

11.4.1Generally. Except as expressly permitted herein, this Agreement may not be assigned or transferred by any Party, nor may any Party assign or transfer any rights or obligations created by this Agreement, except as expressly permitted hereunder without the prior written consent of the other Party, which consent will not be unreasonably withheld.

11.4.2Celgene. Notwithstanding the limitations in Section 11.4.1, and subject to Section 5.5.2 and the remaining provisions of this Section 11.4.2, Celgene may assign or transfer this Agreement, or any rights or obligations hereunder in whole or in part, to (a) one or more Affiliates (provided, however, that Celgene shall remain fully and unconditionally liable and responsible to the non-assigning Party hereto for the performance and observance of all such duties and obligations by such Affiliate); or (b) its successor in interest in connection with its merger, consolidation, or sale of all or substantially all of its assets or that portion of its business pertaining to the subject matter of this Agreement.

11.4.3Prothena. Notwithstanding the limitations in Section 11.4.1, and subject to Section 5.5.2 and the remaining provisions of this Section 11.4.3, Prothena may assign or transfer this Agreement, or any rights or obligations hereunder in whole or in part, to (a) one or more Affiliates (provided, however, that Prothena shall remain fully and unconditionally liable and responsible to the non-assigning Party hereto for the performance and observance of all such duties and obligations by such Affiliate); or (b) its successor in interest in connection with its merger, consolidation, or sale of all or substantially all of its assets.

11.4.4Intellectual Property of Acquiror. Notwithstanding anything to the contrary in this Agreement, if a Party undergoes a Change of Control with, or is otherwise is acquired by a Third Party after the Effective Date, then with respect to any intellectual property rights controlled by such Third Party or its Affiliates (other than one of the Parties to this Agreement or any of its Affiliates immediately prior to such transaction), such intellectual property rights shall not be included in the technology and intellectual property rights licensed to the other Party hereunder to the extent held immediately prior to such transaction by such Third Party or any of its Affiliates (other than the relevant Party to this Agreement or any of its Affiliates immediately prior to such transaction), and developed outside the scope of activities conducted with respect to the Collaboration, any Program, any U.S. License Agreement or any Global License Agreement. The Prothena IP shall also exclude any intellectual property developed [***] by such Third Party [***]; provided that, (a) such intellectual property is developed independently of the activities under this Agreement, the Collaboration, any Program, the Collaboration Agreement, any U.S. License Agreement or any Global License Agreement [***], (b) Prothena and its Affiliates put in place firewalls and other protections [***] and (c) [***].

11.4.5All Other Assignments Null and Void. The terms of this Agreement will be binding upon and will inure to the benefit of the successors, heirs, administrators and permitted assigns of the applicable Party. Any purported assignment in violation of this Section 11.4 will be null and void ab initio.

11.5Change of Control and Other Acquisition Transactions of [***].

11.5.1Notwithstanding anything to the contrary in this Agreement, the Collaboration Agreement, or any other U.S. License Agreement or Global License Agreement (whether the Acquisition Transaction is completed prior to or following execution thereof), (each, a “Transaction Agreement”), if, following the Effective Date, [***] undergoes a Change of Control with, or is otherwise acquired (whether by merger or acquisition of all or substantially all of its shares or assets) by a Third Party (an “Acquisition Transaction”), and as of the date of such Acquisition Transaction or any time thereafter, such Third Party or any of its Affiliates [***] owns or has or obtains rights to a [***], that, following such Acquisition Transaction, (a) [***] or (b) [***]; provided that (x) [***] or, except as explicitly provided pursuant to a separate agreement between [***] and such Third Party or any of its Affiliates [***] with such separate agreement [***] the Acquisition Transaction, [***].

11.5.2Without limiting Section 11.5.1 of this Agreement:

(a)[***];

(b)[***]; and

(c)[***].

11.5.3Personnel. For purposes of Sections 4.4 and 11.4.4 of this Agreement, Section 12.4.4 of the Collaboration Agreement, Sections 4.4, 4.5.2 and 11.4.4 of the Form of Global License Agreement attached to the Collaboration Agreement, and Sections 4.4 and 11.4.4 of the Form of U.S. License Agreement attached to the Collaboration Agreement, [***].

11.5.4New Transaction Agreements. For clarity, the Parties acknowledge and agree that, notwithstanding the terms set forth in the Form of U.S. License Agreement and Form of Global License Agreement attached to the Collaboration Agreement, any U.S. License Agreements and Global License Agreements entered into following the date hereof shall reflect the terms and conditions agreed upon in this Section 11.5.

11.6Waivers and Modifications. The failure of any Party to insist on the performance of any obligation hereunder shall not be deemed to be a waiver of such obligation. Waiver of any breach of any provision hereof shall not be deemed to be a waiver of any other breach of such provision or any other provision on such occasion or any succeeding occasion. No waiver, modification, release, or amendment of any obligation under or provision of this Agreement shall be valid or effective unless in writing and signed by the Parties.

11.7WAIVER OF JURY TRIAL. EXCEPT AS LIMITED BY APPLICABLE LAW, EACH PARTY HERETO HEREBY IRREVOCABLY WAIVES ALL RIGHT TO TRIAL BY JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM (WHETHER BASED IN CONTRACT, TORT OR OTHERWISE) ARISING OUT OF OR RELATING TO THIS

AGREEMENT OR THE ACTIONS OF ANY PARTY HERETO IN THE NEGOTIATION, ADMINISTRATION, PERFORMANCE AND ENFORCEMENT HEREOF.

11.8Choice of Law; Dispute Resolution.

11.8.1Choice of Law. This Agreement shall be governed by, enforced and construed in accordance with the laws of the State of New York without reference to any rules of conflict of laws or renvoi and excluding the United Nations Convention on Contracts for the International Sales of Goods; provided, however, that with respect to matters involving the validity or infringement of intellectual property rights in a given country, such matter may be brought in the applicable country (in accordance with Section 11.8.3) and the Applicable Laws of the applicable country shall apply (subject to Section 6.6.1).

11.8.2Exclusive Dispute Resolution Mechanism. The Parties agree that the procedures set forth in Section 11.8.3 will be the exclusive mechanism for resolving any dispute (whether in contract, tort or otherwise), controversy or claim between the Parties arising out of or in connection with this Agreement, any Party’s rights or obligations under this Agreement, breach of this Agreement or the transactions contemplated by this Agreement (each, a “Dispute”); provided that decisions that are subject to the decision making authority of a given Party, as expressly set forth in this Agreement, will not be subject to the provisions of Section 11.8.3 so long as such decisions are made in accordance with this Agreement.

11.8.3Jurisdiction.

(a)Except as otherwise set forth in this Section 11.8.3, the sole jurisdiction and venue for all actions, suits and proceedings arising out of any Dispute (except in respect of an Excluded Claim, where jurisdiction is non-exclusive) will be the state and federal courts located in the Borough of Manhattan in New York, New York, USA. Each Party hereby irrevocably and unconditionally (a) consents to submit to the exclusive jurisdiction of the state and federal courts located in the Borough of Manhattan in New York, New York, USA for any action, suit or proceeding arising out of such Dispute, and (b) waives any objection to the laying of venue of any action, suit or proceeding arising out of such Dispute in the state and federal courts of the Borough of Manhattan in New York, New York, USA and agrees not to plead or claim in any such court that any such action, suit or proceeding brought in any such court has been brought in an inconvenient forum. Each of the Parties agrees that process may be served upon it in the manner specified in Section 11.2 and irrevocably waives and covenants not to assert or plead any objection which it might otherwise have to such jurisdiction, or to such manner of service of process. It shall be a condition precedent to the commencement of any action in court or other tribunal (save an action for an interim injunction or provisional relief) in respect of any Dispute relating to this Agreement that the Parties have sought to resolve the Dispute by either Party notifying the other Party in writing for resolution to the Executive Officers who shall meet (whether in person or via teleconference) within [***] Business Days of such notice to seek resolution in good faith. If the Executive Officers are unable to resolve the Dispute at such meeting, either Party may pursue any remedy available to such Party at law or in equity, subject to the terms and conditions of this Agreement, including this Section 11.8.3.

(b)Notwithstanding the provisions of Section 11.8.3(a), either Party may, without waiving any remedy under this Agreement, seek from any court having jurisdiction any equitable relief, including any injunctive or provisional relief and specific performance to protect the rights or property of that Party. Such remedies will not be deemed to be the exclusive remedies for a breach of this Agreement but will be in addition to all other remedies available at law or equity. In addition, notwithstanding the provisions of Section 11.8.3(a) either Party may bring an action in any court having jurisdiction to enforce an award rendered pursuant to Section 11.8.3(a).

(c)Until final resolution of the dispute through judicial determination, (i) this Agreement will remain in full force and effect and (ii) the time periods for cure as to any termination will be tolled. The Parties further agree that any payments made pursuant to this Agreement pending resolution of the dispute shall be refunded if a court determines that such payments are not due.

(d)As used in this Section 11.8, the term “Excluded Claim” means a dispute, controversy or claim that concerns (i) the validity or infringement of a Patent, trademark or copyright, or (ii) any antitrust, anti-monopoly or competition law or regulation, whether or not statutory.

11.9Relationship of the Parties. Prothena and Celgene are independent contractors under this Agreement. Nothing contained herein is intended or is to be construed so as to constitute (a) Prothena as a partner, agent, or joint venturer of Celgene or (b) Celgene as a partner, agent or joint venturer of Prothena. Neither Prothena nor Celgene, respectively, shall have any express or implied right or authority to assume or create any obligations on behalf of or in the name of Celgene or Prothena, respectively, or to bind Celgene or Prothena, respectively, to any contract, agreement, or undertaking with any Third Party.

11.10Third Party Beneficiaries. There are no express or implied Third Party beneficiaries hereunder. The provisions of this Agreement are for the exclusive benefit of the Parties, and no other person or entity shall have any right or claim against any Party by reason of these provisions or be entitled to enforce any of these provisions against any Party.

11.11Entire Agreement. This Agreement, together with the attached Exhibits and Schedules and the Master Collaboration Agreement, contains the entire agreement by the Parties with respect to the subject matter hereof and supersedes any prior express or implied agreements, understandings and representations, either oral or written, which may have related to the subject matter hereof in any way, including any and all term sheets relating to the transactions contemplated by this Agreement and exchanged between the Parties prior to the Effective Date. In the event of a conflict between the provisions of this Agreement and the Master Collaboration Agreement with respect to the Licensed Program, the provisions of this Agreement shall control.

11.12Counterparts. This Agreement may be executed in counterparts with the same effect as if both Parties had signed the same document. All such counterparts shall be deemed an original, shall be construed together, and shall constitute one and the same instrument. Any such counterpart, to the extent delivered by means of a fax machine or by .pdf, .tif, .gif, .jpeg or similar attachment to electronic mail (any such delivery, an “Electronic Delivery”) shall be

treated in all manner and respects as an original executed counterpart and shall be considered to have the same binding legal effect as if it were the original signed version thereof delivered in person. No Party hereto shall raise the use of Electronic Delivery to deliver a signature or the fact that any signature or agreement or instrument was transmitted or communicated through the use of Electronic Delivery as a defense to the formation of a contract, and each Party forever waives any such defense, except to the extent that such defense relates to lack of authenticity.

11.13Equitable Relief; Cumulative Remedies. Notwithstanding anything to the contrary herein, the Parties shall be entitled to seek equitable relief, including injunction and specific performance, as a remedy for any breach of this Agreement. Such remedies shall not be deemed to be the exclusive remedies for a breach of this Agreement but shall be in addition to all other remedies available at law or equity. The Parties further agree not to raise as a defense or objection to the request or granting of such relief that any breach of this Agreement is or would be compensable by an award of money damages. No remedy referred to in this Agreement is intended to be exclusive, but each shall be cumulative and in addition to any other remedy referred to in this Agreement or otherwise available under Applicable Law.

11.14Interpretation.

11.14.1Generally. This Agreement has been diligently reviewed by and negotiated by and among the Parties, and in such negotiations each of the Parties has been represented by competent (in-house or external) counsel, and the final agreement contained herein, including the language whereby it has been expressed, represents the joint efforts of the Parties and their counsel. Accordingly, in interpreting this Agreement or any provision hereof, no presumption shall apply against any Party as being responsible for the wording or drafting of this Agreement or any such provision, and ambiguities, if any, in this Agreement shall not be construed against any Party, irrespective of which Party may be deemed to have authored the ambiguous provision.

11.14.2Definitions; Interpretation. The definitions of the terms herein shall apply equally to the singular and plural forms of the terms defined and where a word or phrase is defined herein, each of its other grammatical forms shall have a corresponding meaning. Whenever the context may require, any pronoun shall include the corresponding masculine, feminine, and neuter forms. The word “will” shall be construed to have the same meaning and effect as the word “shall.” The word “any” shall mean “any and all” unless otherwise clearly indicated by context. The words “including,” “includes,” “include,” “for example,” and “e.g.” and words of similar import will be deemed to be followed by the words “without limitation.” The word “or” is disjunctive but not necessarily exclusive. The words “hereof,” “herein” and “herewith” and words of similar import shall, unless otherwise stated, be construed to refer to this Agreement as a whole and not to any particular provision of this Agreement. Unless the context requires otherwise or otherwise specifically provided, (i) all references herein to Articles, Sections, Schedules or Exhibits shall be construed to refer to Articles, Sections, Schedules and Exhibits of this Agreement and (ii) reference in any Section to any subclauses are references to such subclauses of such Section.

11.14.3Subsequent Events. Unless the context requires otherwise, (i) any definition of or reference to any agreement, instrument, or other document herein shall be

construed as referring to such agreement, instrument, or other document as from time to time amended, supplemented, or otherwise modified (subject to any restrictions on such amendments, supplements, or modifications set forth herein), (ii) any reference to any Applicable Law herein shall be construed as referring to such Applicable Law as from time to time enacted, repealed, or amended, and (iii) any reference herein to any Person shall be construed to include the Person’s successors and assigns (subject to Section 11.4).

11.14.4Headings. Headings, captions and the table of contents are for convenience only and are not to be used in the interpretation of this Agreement.

11.14.5Prior Drafts. No prior draft of this Agreement nor any course of performance or course of dealing shall be used in the interpretation or construction of this Agreement.

11.14.6Independent Significance. Although the same or similar subject matters may be addressed in different provisions of this Agreement, the Parties intend that, except as reasonably apparent on the face of the Agreement or as expressly provided in this Agreement, each such provision shall be read separately, be given independent significance and not be construed as limiting any other provision of this Agreement (whether or not more general or more specific in scope, substance or content).

11.15Further Assurances. Each Party shall execute, acknowledge and deliver such further instruments, and do all such other ministerial, administrative or similar acts, as may be reasonably necessary or appropriate in order to carry out the expressly stated purposes and the clear intent of this Agreement.

11.16Extension to Affiliates. Subject to Sections 5.5.2 and 11.4, Celgene shall have the right to extend the rights, licenses, immunities and obligations granted in this Agreement to one or more of its Affiliates. All applicable terms and provisions of this Agreement shall apply to any such Affiliate to which this Agreement has been extended to the same extent as such terms and provisions apply to Celgene. Celgene shall remain fully liable for any acts or omissions of such Affiliates.

11.17Financial Transparency. Prothena acknowledges that Celgene is subject to applicable laws related to the collection and reporting of any payments or transfers of value to certain healthcare providers and teaching hospitals (collectively, “Financial Transparency Laws”), which include, without limitation, relevant provisions of the Affordable Care Act of 2010 and its implementing regulations for the United States along with similar laws and regulations in other countries. Prothena shall reasonably cooperate with Celgene, at Celgene’ cost for Prothena’s reasonable expenses, in its compliance with Financial Transparency Laws and promptly provide any information reasonably requested by Celgene in connection with this Agreement in a mutually agreed upon format to the extent reasonably necessary for Celgene to comply with its obligations under the Financial Transparency Laws. Celgene shall have the right to allocate payments or other transfers of value in connection with this Agreement in any required reporting under Financial Transparency Laws in accordance with its normal business practices.

[Signature Page Follows]

IN WITNESS WHEREOF, and intending to be legally bound hereby, the Parties have caused this U.S. LICENSE AGREEMENT to be executed by their respective duly authorized officers as of the Effective Date.


PROTHENA BIOSCIENCES LIMITED			CELGENE SWITZERLAND LLC


By: /s/ Yvonne Tchrakian			By: /s/ Kevin Mello

Name: Yvonne Tchrakian			Name: Kevin Mello

Title: Director			Title: Manager

[Signature Page to U.S. License Agreement]

AMENDMENT NUMBER ONE
TO
U.S. LICENSE AGREEMENT

THIS AMENDMENT NUMBER ONE TO U.S. LICENSE AGREEMENT (this “Amendment”) is effective as of August 12, 2021 (the “Amendment Effective Date”) and is made and entered into by and between Prothena Biosciences Limited (“Prothena”) and Celgene Switzerland LLC (“Celgene”).

RECITALS

WHEREAS, Prothena and Celgene are parties to that certain U.S. License Agreement, dated as of July 30, 2021, (the “Agreement”); and

WHEREAS, Prothena and Celgene wish to amend the Agreement as set forth herein.

NOW, THEREFORE, in consideration of the foregoing recitals and the mutual agreements contained herein, Prothena and Celgene, intending to be legally bound hereby, agree as follows, effective as of the Amendment Effective Date:

AGREEMENT

1.Amendments. Sections 11.4.4 and 11.5 of the Agreement are hereby amended by inserting the word “Master” immediately prior to every instance of the term “Collaboration Agreement” in such sections. For the avoidance of doubt, such terms will now read “Master Collaboration Agreement” rather than “Collaboration Agreement”.

2.Defined Terms. Capitalized terms used in this Amendment (including in the Recitals) but that are not defined herein shall have the meanings given to them in the Agreement.

3.Governing Law. This Amendment shall be governed by and construed in accordance with the laws of the State of New York.

4.Miscellaneous. Except as specifically set forth herein, all the terms and provisions of the Agreement shall remain unchanged, unmodified and in full force and effect, and the Agreement shall be read together and construed with this Amendment. This Amendment may be executed in any number of counterparts, all of which taken together shall constitute one and the same amendatory instrument and any of the parties hereto may execute this Amendment by signing one counterpart. Any such counterpart, to the extent delivered by means of a fax machine or by .pdf, .tif, .gif, .jpeg or similar attachment to electronic mail shall be treated in all manner and respects as an original executed counterpart and shall be considered to have the same binding legal effect as if it were the original signed version thereof delivered in person. This Amendment, together with the Agreement as amended hereby, shall supersede and replace any prior agreement between the parties relating to the subject matter hereof.

[Signature Page Follows]

IN WITNESS WHEREOF, the Parties hereto have caused this Amendment to be executed by their respective authorized representatives effective as of the Amendment Effective Date set forth above.

PROTHENA BIOSCIENCES LIMITED CELGENE SWITZERLAND LLC

By: /s/ Yvonne Tchrakian By: /s/ Kevin Mello

Printed Name: Yvonne Tchrakian Printed Name: Kevin Mello

Title: Director Title: Manager

Date: August 12, 2021 Date: August 12, 2021

Signature Page to Amendment Number One to U.S. License Agreement

AMENDMENT NUMBER TWO
TO
U.S. LICENSE AGREEMENT

THIS AMENDMENT NUMBER TWO TO U.S. LICENSE AGREEMENT (this “Amendment”) is effective as of September 8, 2021 (the “Amendment Effective Date”) and is made and entered into by and between Prothena Biosciences Limited (“Prothena”) and Celgene Switzerland LLC (“Celgene”).

RECITALS

WHEREAS, Prothena and Celgene entered into that certain U.S. License Agreement, dated as of July 30, 2021, which was amended by Amendment Number One to U.S. License Agreement having an effective date of August 12, 2021 (as amended, the “Agreement”); and

WHEREAS, Prothena and Celgene wish to amend the Agreement as set forth herein.

AGREEMENT

1.Amendment. Section 10.14 of the Agreement is hereby deleted in its entirety and replaced with the following:

“10.14 Termination for Safety Reason. Either Party may suspend conduct of any Development activity delegated to a Party hereunder, and [***] further may terminate this Agreement on a Licensed Antibody-by-Licensed Antibody or Licensed Product-by-Licensed Product basis, upon written notice to the other Party based on a Safety Reason. In the Event of such suspension or notice of termination for a Safety Reason, prior to the suspending or terminating Party providing written notice, each Party’s safety committee shall, to the extent practicable, meet and discuss in good faith the safety concerns raised by the suspending or terminating Party and consider in good faith the input, questions and advice of the non-suspending or non-terminating Party. The Party suspending the conduct of a Development activity for a Safety Reason shall be responsible, at its expense, for the suspension, and [***], for the wind-down of any Development of the applicable Licensed Antibody or Licensed Product (including any Clinical Trials for the applicable Licensed Product being conducted by or on behalf of [***]) and any Commercialization activities for the applicable Licensed Product. In the event of a termination under this Section 10.14, such termination shall become effective upon the date that [***] notifies [***] in writing that such wind-down is complete. [***] For clarity, the Parties acknowledge and agree that, notwithstanding the terms set forth in the Form of U.S. License Agreement and Form of Global License Agreement attached to the Master Collaboration Agreement, any U.S. License Agreements and Global License Agreements entered into following the date hereof shall reflect the terms and conditions agreed upon in this Section 10.14.”

2.Defined Terms. Capitalized terms used in this Amendment (including in the Recitals) but that are not defined herein shall have the meanings given to them in the Agreement.

3.Governing Law. This Amendment shall be governed by and construed in accordance with the laws of the State of New York.

[Signature Page Follows]

IN WITNESS WHEREOF, the Parties hereto have caused this Amendment to be executed by their respective authorized representatives effective as of the Amendment Effective Date set forth above.

PROTHENA BIOSCIENCES LIMITED CELGENE SWITZERLAND LLC

By: /s/ Olivia Waldron By: /s/ Kevin Mello

Printed Name: Olivia Waldron Printed Name: Kevin Mello

Title: Assistant Company Secretary Title: Manager

Date: September 14, 2021 Date: September 14, 2021

Signature Page to Amendment Number Two to U.S. License Agreement

Exhibit 31.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER

PURSUANT TO RULE 13a-14(a)/15d-14(a), AS ADOPTED PURSUANT TO SECTION 302 OF

THE SARBANES-OXLEY ACT OF 2002

I, Gene G. Kinney, certify that:

1.I have reviewed this Quarterly Report on Form 10-Q of Prothena Corporation plc;

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

(a)Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

(b)Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

(c)Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

(d)Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5.The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

(a)All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

(b)Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.


Date:	November 4, 2021	/s/ Gene G. Kinney
		Gene G. Kinney
		President and Chief Executive Officer
		(Principal Executive Officer)

Exhibit 31.2

CERTIFICATION OF CHIEF FINANCIAL OFFICER

PURSUANT TO RULE 13a-14(a)/15d-14(a), AS ADOPTED PURSUANT TO SECTION 302 OF

THE SARBANES-OXLEY ACT OF 2002

I, Tran B. Nguyen, certify that:

1.I have reviewed this Quarterly Report on Form 10-Q of Prothena Corporation plc;

(a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

(b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.


Date:	November 4, 2021	/s/ Tran B. Nguyen
		Tran B. Nguyen
		Chief Financial Officer
		(Principal Financial Officer)

Exhibit 32.1

CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER

AND PRINCIPAL FINANCIAL OFFICER

PURSUANT TO 18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO SECTION 906

OF THE SARBANES-OXLEY ACT OF 2002

Pursuant to the requirement set forth in Rule 13a-14(b) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C. §1350), Gene G. Kinney, President and Chief Executive Officer of Prothena Corporation plc (the “Company”) and Tran B. Nguyen, Chief Financial Officer of the Company, each hereby certify that, to the best of his knowledge:

1.The Company’s Quarterly Report on Form 10-Q for the fiscal quarter ended September 30, 2021, to which this Certification is attached as Exhibit 32.1 (the “Report”) fully complies with the requirements of Section 13(a) or Section 15(d) of the Exchange Act; and

2.The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.


Date:	November 4, 2021	/s/ Gene G. Kinney
		Gene G. Kinney
		President and Chief Executive Officer
		(Principal Executive Officer)


		/s/ Tran B. Nguyen
		Tran B. Nguyen
		Chief Financial Officer
		(Principal Financial Officer)

A signed original of this written statement required by Rule 13a-14(b) of the Securities Exchange Act of 1934 and 18 U.S.C. Section 1350 has been provided to the Company and will be retained by the Company and furnished to the Securities and Exchange Commission or its staff upon request.

This certification accompanies the Form 10-K to which it relates, is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (whether made before or after the date of the Form 10-K), irrespective of any general incorporation language contained in such filing.


Sales Milestone Event			Sales Milestone Payment
First achievement of Per Licensed Product Annual Net Sales of the Licensed Products in any single Calendar Year exceeding [*] Dollars ($[*])			[*] Dollars ($[*])
First achievement of Per Licensed Product Annual Net Sales of the Licensed Products in any single Calendar Year exceeding [*] Dollars ($[*])			[*] Dollars ($[*])
First achievement of Per Licensed Product Annual Net Sales of the Licensed Products in any single Calendar Year exceeding [*] Dollars ($[*])			[*] Dollars ($[*])
First achievement of Per Licensed Product Annual Net Sales of the Licensed Products in any single Calendar Year exceeding [*] Dollars ($[*])			[*] Dollars ($[*])