Rubius Therapeutics, Inc. (Form: S-3, Received: 08/01/2019 17:21:09)

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As filed with the Securities and Exchange Commission on August 1, 2019.

Registration No. 333-

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

Rubius Therapeutics, Inc.
(Exact name of registrant as specified in its charter)


Delaware		46-2688109
(State or other jurisdiction of incorporation or organization)		(I.R.S. Employer Identification Number)

399 Binney Street, Suite 300
Cambridge, MA 02139
(Address of principal executive offices)

(617) 679-9600
(Registrant's telephone number, including area code)

Pablo J. Cagnoni
Chief Executive Officer
Rubius Therapeutics, Inc.
399 Binney Street, Suite 300
Cambridge, MA 02139
(617) 679-9600
(Name, address, including zip code, and telephone number, including area code, of agent for service)

With copies to:

Stuart M. Cable, Esq.
Arthur R. McGivern, Esq.
Sarah Ashfaq, Esq.
Goodwin Procter LLP
100 Northern Avenue
Boston, MA 02210
(617) 570-1000

Approximate date of commencement of proposed sale to the public:
From time to time after this Registration Statement becomes effective.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, as amended, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box: ý

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. o

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the 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 o		Accelerated filer o		Non-accelerated filer ý		Smaller reporting company o Emerging growth company ý

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 7(a)(2)(B) of the Securities Act. o

CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities to be Registered	Amount to be Registered	Proposed Maximum Offering Price Per Unit	Proposed Maximum Aggregate Offering Price	Amount of Registration Fee




Common Stock(5)	—	—	—	—

Preferred Stock(6)	—	—	—	—

Debt Securities(7)	—	—	—	—

Warrants(8)	—	—	—	—

Units(9)	—	—	—	—

Total Offering	$450,000,000(1)	(2)	$450,000,000(3)	$54,540(4)

Total Registration Fee				$54,540(4)

(1): The amount to be registered consists of up to $450,000,000 of an indeterminate amount of common stock, preferred stock, debt securities, warrants and/or units. There is also being registered hereunder such currently indeterminate number of (i) shares of common stock or other securities of the registrant as may be issued upon conversion of, or in exchange for, convertible or exchangeable debt securities and/or preferred stock registered hereby, or (ii) shares of preferred stock, common stock, debt securities or units as may be issued upon exercise of warrants registered hereby, as the case may be. Any securities registered hereunder may be sold separately or as units with the other securities registered hereunder.
(2): The proposed maximum aggregate offering price per unit will be determined from time to time by the registrant in connection with the issuance by the registrant of the securities registered hereunder and is not specified as to each class of security pursuant to General Instruction II.D. of Form S-3 under the Securities Act.
(3): Estimated solely for purposes of computing the registration fee. No separate consideration will be received for (i) common stock or other securities of the registrant that may be issued upon conversion of, or in exchange for, convertible or exchangeable debt securities and/or preferred stock registered hereby, or (ii) preferred stock, common stock, debt securities or units that may be issued upon exercise of warrants registered hereby, as the case may be.
(4): The registration fee has been calculated in accordance with Rule 457(o) under the Securities Act.
(5): Including such indeterminate amount of common stock as may be issued from time to time at indeterminate prices or upon conversion of debt securities and/or preferred stock registered hereby, or upon exercise of warrants registered hereby, as the case may be.
(6): Including such indeterminate amount of preferred stock as may be issued from time to time at indeterminate prices or upon conversion of debt securities and/or preferred stock registered hereby, or upon exercise of warrants registered hereby, as the case may be.
(7): Including such indeterminate principal amount of debt securities as may be issued from time to time at indeterminate prices or upon exercise of warrants registered hereby, as the case may be.
(8): Including such indeterminate number of warrants or other rights, including without limitation share purchase or subscription rights, as may be issued from time to time at indeterminate prices.
(9): Each unit will be issued under a unit agreement and will represent an interest in two or more securities, which may or may not be separable from one another.

THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF THE SECURITIES ACT OF 1933, AS AMENDED, OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME EFFECTIVE ON SUCH DATE AS THE COMMISSION ACTING PURSUANT TO SAID SECTION 8(a), MAY DETERMINE.

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EXPLANATORY NOTE

This registration statement contains:

•: a base prospectus which covers the offering, issuance and sale by us of up to $450,000,000 in the aggregate of the securities identified above, from time to time, subject to market conditions and prices, liquidity objectives and other investment considerations; and
•: a distribution agreement prospectus supplement covering the offering, issuance and sale by us of up to a maximum aggregate offering price of $100,000,000 of our common stock that may be issued and sold under a distribution agreement, or the Distribution Agreement, entered into with J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC (which we refer to collectively as the "Sales Agents," and each individually as a "Sales Agent"), dated August 1, 2019.

The base prospectus immediately follows this explanatory note. The specific terms of any securities to be offered by us pursuant to the base prospectus, other than the shares under the Distribution Agreement, will be specified in a prospectus supplement to the base prospectus. The specific terms of the securities to be issued and sold under the Distribution Agreement are specified in the distribution agreement prospectus supplement that immediately follows the base prospectus. The $100,000,000 of common stock that may be offered, issued and sold under the distribution agreement prospectus supplement is included in the $450,000,000 of securities that may be offered, issued and sold by us under the base prospectus. Upon termination of the Distribution Agreement with the Sales Agents, any portion of the $100,000,000 included in the distribution agreement prospectus supplement that is not sold pursuant to the Distribution Agreement will be available for sale in other offerings pursuant to the base prospectus and a corresponding prospectus supplement, and if no shares are sold under the Distribution Agreement, the full $100,000,000 of securities may be sold in other offerings by us pursuant to the base prospectus and a corresponding prospectus supplement.

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The information in this prospectus is not complete and may be changed. These securities may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell nor does it seek an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION,
DATED AUGUST 1, 2019.

PROSPECTUS

$450,000,000

Common Stock
Preferred Stock
Debt Securities
Warrants
Units

We may from time to time issue, in one or more series or classes, up to $450,000,000 in aggregate principal amount of our common stock, preferred stock, debt securities, warrants and/or units, in any combination, together or separately, in one or more offerings in amounts at prices and on the terms that we will determine at the time of the offering and which will be set forth in a prospectus supplement and any related free writing prospectus.

We may offer these securities separately or together in units. Each time we sell securities described herein, we will provide prospective investors with a supplement to this prospectus that will specify the terms of the securities being offered. We may sell these securities to or through underwriters or dealers and also to other purchasers or through agents. We will set forth the names of any underwriters or agents, and any fees, conversions, or discount arrangements, in the accompanying prospectus supplement. We may not sell any securities under this prospectus without delivery of the applicable prospectus supplement. You should read this document and any prospectus supplement or amendment carefully before you invest in our securities.

Our common stock is listed on The Nasdaq Global Select Market under the symbol "RUBY". On July 29, 2019, the closing price for our common stock, as reported on The Nasdaq Global Select Market, was $14.59 per share. Our principal executive offices are located at 399 Binney Street, Suite 300, Cambridge, Massachusetts 02139.

Investing in our securities involves a high degree of risk. You should review carefully the risks and uncertainties described under the heading "Risk Factors" contained in this prospectus beginning on page 2 and any applicable prospectus supplement, and under similar headings in the other documents that are incorporated by reference into this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is , 2019

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		Page

About this Prospectus			1
Risk Factors			2
Cautionary Statement Regarding Forward-Looking Statements			3
The Company			5
Use of Proceeds			6
Securities We May Offer			7
Description of Capital Stock			8
Description of Debt Securities			14
Description of Warrants			21
Description of Units			22
Plan of Distribution			25
Legal Matters			28
Experts			28
Where You Can Find More Information			28
Incorporation by Reference			28

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, or the SEC, using a "shelf" registration process. Under this shelf registration process, we may from time to time sell any combination of the securities described in this prospectus in one or more offerings for an aggregate initial offering price of up to $450,000,000.

This prospectus provides you with a general description of the securities we may offer. Each time we sell securities described herein, we will provide one or more prospectus supplements that will contain specific information about the terms of the offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and the accompanying prospectus supplement together with the additional information described under the heading "Where You Can Find More Information" beginning on page 28 of this prospectus.

You should rely only on the information contained in or incorporated by reference in this prospectus, any accompanying prospectus supplement or in any related free writing prospectus filed by us with the SEC. We have not authorized anyone to provide you with different information. This prospectus and the accompanying prospectus supplement do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the securities described in the accompanying prospectus supplement or an offer to sell or the solicitation of an offer to buy such securities in any circumstances in which such offer or solicitation is unlawful. You should assume that the information appearing in this prospectus, any prospectus supplement, the documents incorporated by reference and any related free writing prospectus is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed materially since those dates.

THIS PROSPECTUS MAY NOT BE USED TO OFFER AND SELL SECURITIES UNLESS IT IS ACCOMPANIED BY AN ADDITIONAL PROSPECTUS OR A PROSPECTUS SUPPLEMENT.

As used in this prospectus, unless the context otherwise requires, references to the "company," "we," "us" and "our" refer to Rubius Therapeutics, Inc. and, where appropriate, our subsidiary.

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RISK FACTORS

Investing in our securities involves a high degree of risk. You should carefully consider the risks referenced below and described in the documents incorporated by reference in this prospectus and any applicable prospectus supplement, as well as other information we include or incorporate by reference into this prospectus and any applicable prospectus supplement, before making an investment decision. Our business, financial condition or results of operations could be materially adversely affected by the materialization of any of these risks. The trading price of our securities could decline due to the materialization of any of these risks, and you may lose all or part of your investment. This prospectus and the documents incorporated herein by reference also contain forward-looking statements that involve risks and uncertainties. Actual results could differ materially from those anticipated in these forward-looking statements as a result of certain factors, including the risks described below and in the documents incorporated herein by reference, including (i) our Annual Report on Form 10-K for the fiscal year ended December 31, 2018 , which is on file with the SEC and is incorporated herein by reference, (ii) our Quarterly Report on Form 10-Q for the quarter ended March 31, 2019 , which is on file with the SEC and is incorporated herein by reference, and (iii) other documents we file with the SEC that are deemed incorporated by reference into this prospectus.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, including the documents that we incorporate by reference, contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act. Any statements about our expectations, beliefs, plans, objectives, assumptions or future events or performance are not historical facts and may be forward-looking. These statements are often, but are not always, made through the use of words or phrases such as "may," "will," "could," "should," "expects," "intends," "plans," "anticipates," "believes," "estimates," "predicts," "projects," "potential," "continue," and similar expressions, or the negative of these terms, or similar expressions. Accordingly, these statements involve estimates, assumptions, risks and uncertainties which could cause actual results to differ materially from those expressed in them. Any forward-looking statements are qualified in their entirety by reference to the factors discussed throughout this prospectus, and in particular those factors referenced in the section "Risk Factors."

This prospectus contains forward-looking statements that are based on our management's belief and assumptions and on information currently available to our management. These statements relate to future events or our future financial performance, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed or implied by these forward-looking statements. Forward-looking statements include, but are not limited to, statements about:

•: the success, cost and timing of our product development activities and clinical trials, including statements regarding the timing of initiation and completion of studies or trials and related preparatory work, the period during which the results of the trials will become available, and our research and development programs;
•: our ability to advance any product candidate into or successfully complete any clinical trial;
•: our ability or the potential to successfully manufacture our product candidates for clinical trials or for commercial use, if approved;
•: our plans to renovate, customize and operate our manufacturing facility purchased in 2018;
•: the potential for our identified research priorities to advance our technologies;
•: our ability to maintain regulatory approval, if obtained, of any of our current or future product candidates, and any related restrictions, limitations and/or warnings in the label of an approved product candidate;
•: the ability to license additional intellectual property relating to our product candidates and to comply with our existing license agreements;
•: our ability to commercialize our products in light of the intellectual property rights of others;
•: developments relating to cellular therapies, including red blood cell therapies;
•: the success of competing therapies that are or become available;
•: our ability to obtain funding for our operations, including funding necessary to complete further development and commercialization of our product candidates;
•: the commercialization of our product candidates, if approved;
•: our plans to research, develop and commercialize our product candidates;
•: our ability to attract collaborators with development, regulatory and commercialization expertise;

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•: future agreements with third parties in connection with the commercialization of our product candidates and any other approved product;
•: the size and growth potential of the markets for our product candidates, and our ability to serve those markets;
•: the rate and degree of market acceptance of our product candidates;
•: regulatory developments in the United States and foreign countries;
•: our ability to contract with third-party suppliers and manufacturers and their ability to perform adequately;
•: our ability to attract and retain key scientific or management personnel;
•: the accuracy of our estimates regarding expenses, future revenue, capital requirements and needs for additional financing;
•: the impact of laws and regulations;
•: our expectations regarding our ability to obtain and maintain intellectual property protection for our product candidates;
•: our expectations regarding the period during which we qualify as an "emerging growth company" under the Jumpstart Our Business Startups Act; and
•: our use of the proceeds from the initial public offering and any offering pursuant to this prospectus.

This prospectus and the documents incorporated by reference also contain estimates, projections and other information concerning our industry, our business, and the markets for certain diseases, including data regarding the estimated size of those markets, and the incidence and prevalence of certain medical conditions. Information that is based on estimates, forecasts, projections, market research or similar methodologies is inherently subject to uncertainties and actual events or circumstances may differ materially from events and circumstances reflected in this information. Unless otherwise expressly stated, we obtained this industry, business, market and other data from reports, research surveys, studies and similar data prepared by market research firms and other third parties, industry, medical and general publications, government data and similar sources.

You should read this prospectus and the documents that we incorporate by reference in this prospectus completely and with the understanding that our actual future results may be materially different from what we expect. The forward-looking statements in this prospectus and the documents we incorporate by reference herein represent our views as of their respective dates. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we have no current intention of doing so except to the extent required by applicable law. You should, therefore, not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this prospectus.

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THE COMPANY

We are developing a new class of cellular medicines, Red Cell Therapeutics, or RCTs. Based on our vision that human red blood cells are the foundation of the next significant innovation in medicine, we have designed a proprietary platform to genetically engineer and culture RCTs that are selective, potent and ready-to-use cellular therapies. We believe that our RCTs will provide life-changing or life-saving benefits for patients with severe diseases across multiple therapeutic areas.

We have generated hundreds of RCTs using our RED PLATFORM®, a highly versatile and proprietary cellular therapy platform. We are utilizing our universal engineering and manufacturing processes to advance a broad pipeline of RCT product candidates into clinical trials in rare diseases, cancer and autoimmune diseases. Common design and manufacturing elements of our RCTs should enable us to achieve significant advantages in product development. We are establishing end-to-end manufacturing capabilities and plan to develop commercial infrastructure to further establish ourselves as a leading, fully integrated cellular therapy company.

We qualify as an "emerging growth company" as defined in the JOBS Act. As an emerging growth company, we may take advantage of specified reduced disclosure and other requirements that are otherwise applicable generally to public companies. We would cease to be an emerging growth company on the date that is the earliest of: (i) the last day of the fiscal year in which we have total annual gross revenues of $1.07 billion or more; (ii) December 31, 2023; (iii) the date on which we have issued more than $1 billion in nonconvertible debt during the previous three years; or (iv) the date on which we are deemed to be a large accelerated filer under the rules of the SEC.

We were incorporated under the laws of the State of Delaware in April 2013 under the previous name, VL26, Inc. In January 2015, we changed our name to Rubius Therapeutics, Inc. Our principal executive offices are located at 399 Binney Street, Suite 300, Cambridge, MA 02139, and our telephone number is (617) 679-9600. Our website address is www.rubiustx.com. We do not incorporate the information on or accessible through our website into this prospectus, and you should not consider any information on, or that can be accessed through, our website as part of this prospectus. Our common stock trades on The Nasdaq Global Select Market under the symbol "RUBY".

We are the owner of the RUBIUS THERAPEUTICS trademark, as well as certain other trademarks, including design versions of some of these trademarks. Our application for the RED CELL THERAPEUTICS and RED PLATFORM trademarks are currently pending. The symbols ™ and ® are not used in connection with the presentation of these trademarks in this prospectus and their absence does not indicate a lack of trademark rights. Certain other trademarks used in this prospectus are the property of third-party trademark owners and may be presented with or without trademark references.

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USE OF PROCEEDS

We intend to use the net proceeds from the sale of any securities offered under this prospectus for general corporate purposes unless otherwise indicated in the applicable prospectus supplement. General corporate purposes may include research and development costs, including the conduct of one or more clinical trials and/or preclinical studies and process development and manufacturing of our product candidates, potential strategic acquisitions of complementary businesses, services or technologies, expansion of our technology infrastructure and capabilities, working capital, capital expenditures and other general corporate purposes. We may temporarily invest the net proceeds in a variety of capital preservation instruments, including investment grade, interest bearing instruments and U.S. government securities, until they are used for their stated purpose. We have not determined the amount of net proceeds to be used specifically for such purposes. As a result, management will retain broad discretion over the allocation of net proceeds.

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SECURITIES WE MAY OFFER

This prospectus contains summary descriptions of the securities we may offer from time to time. These summary descriptions are not meant to be complete descriptions of each security. The particular terms of any security will be described in the applicable prospectus supplement. This prospectus provides you with a general description of the securities we may offer. Each time we sell securities described herein, we will provide prospective investors with a supplement to this prospectus that will contain specific information about the terms of that offering, including the specific amounts, prices and terms of the securities offered.

We may sell the securities to or through underwriters, dealers or agents, directly to purchasers or through a combination of any of these methods of sale or as otherwise set forth below under "Plan of Distribution." We, as well as any agents acting on our behalf, reserve the sole right to accept and to reject in whole or in part any proposed purchase of securities. Any prospectus supplement will set forth the names of any underwriters, dealers, agents or other entities involved in the sale of securities described in that prospectus supplement and any applicable fee, commission or discount arrangements with them.

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DESCRIPTION OF CAPITAL STOCK

The following description of our common stock and preferred stock, together with the additional information we include in any applicable prospectus supplements, summarizes the material terms and provisions of the common stock and preferred stock that we may offer under this prospectus. The following description of our capital stock does not purport to be complete and is subject to, and qualified in its entirety by, our amended and restated certificate of incorporation and amended and restated by-laws, which are exhibits to the registration statement of which this prospectus forms a part, and by applicable law. The terms of our common stock and preferred stock may also be affected by Delaware law.

Authorized Capital Stock

Our authorized capital stock consists of 150,000,000 shares of common stock, par value $0.001 per share, and 10,000,000 shares of preferred stock, par value $0.001 per share, all of which shares of preferred stock are undesignated.

As of June 30, 2019, 80,077,679 shares of our common stock were outstanding and held by 32 stockholders of record.

Common Stock

The holders of our common stock are entitled to one vote for each share held on all matters submitted to a vote of the stockholders. The holders of our common stock do not have any cumulative voting rights. Holders of our common stock are entitled to receive ratably any dividends, but only when and as declared by our board of directors out of funds legally available for that purpose, subject to any preferential dividend rights of any outstanding preferred stock. Our common stock has no preemptive rights, conversion rights or other subscription rights or redemption or sinking fund provisions.

In the event of our liquidation, dissolution or winding up, holders of our common stock will be entitled to share ratably in all assets remaining after payment of all debts and other liabilities and any liquidation preference of any outstanding preferred stock. All outstanding shares are fully paid and non-assessable.

When we issue shares of common stock under this prospectus, the shares will fully be paid and non-assessable and will not have, or be subject to, any preemptive or similar rights.

Undesignated Preferred Stock

Our board of directors has the authority, without further action by our stockholders, to issue up to 10,000,000 shares of preferred stock in one or more series and to fix the rights, preferences, privileges and restrictions thereof. These rights, preferences and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting, or the designation of, such series, any or all of which may be greater than the rights of common stock. The issuance of our preferred stock could adversely affect the voting power of holders of common stock and the likelihood that such holders will receive dividend payments and payments upon our liquidation. In addition, the issuance of preferred stock could have the effect of delaying, deferring or preventing a change in control of our company or other corporate action. The purpose of authorizing our board of directors to issue preferred stock in one or more series and determine the number of shares in the series and its rights and preferences is to eliminate delays associated with a stockholder vote on specific issuances. In addition, the issuance of preferred stock could have the effect of delaying, deferring or preventing a change in control of our company or other corporate action. When we issue shares of preferred stock under this prospectus, the shares will fully be paid and non-assessable and will not be subject to any preemptive or similar rights.

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The existence of authorized but unissued shares of preferred stock may enable our board of directors to discourage an attempt to obtain control of us by means of a merger, tender offer, proxy contest or otherwise. For example, if in the due exercise of its fiduciary obligations, our board of directors were to determine that a takeover proposal is not in the best interests of our stockholders, our board of directors could cause shares of preferred stock to be issued without stockholder approval in one or more private offerings or other transactions that might dilute the voting or other rights of the proposed acquirer or insurgent stockholder or stockholder group. In this regard, our amended and restated certificate of incorporation, or our certificate of incorporation, grants our board of directors broad power to establish the rights and preferences of authorized and unissued shares of preferred stock. The issuance of shares of preferred stock could decrease the amount of earnings and assets available for distribution to holders of shares of common stock. The issuance may also adversely affect the rights and powers, including voting rights, of these holders and may have the effect of delaying, deterring or preventing a change in control of us.

Registration Rights

Pursuant to the terms of our second amended and restated investors' rights agreement, dated as of February 23, 2018, or the investors' rights agreement, certain of our stockholders are entitled to rights with respect to the registration of their shares under the Securities Act until the earliest of (a) the fifth (5 ^th ) anniversary of our initial public offering, (b) a deemed liquidation event, as defined in the investors' rights agreement, or (c) such time as such holder's registrable securities could be sold without any restriction on volume or manner of sale on any three month period under Rule 144 or any successor rule. We refer to these shares collectively as registrable securities.

Demand Registration Rights

The holders of 38,296,526 shares of our common stock are entitled to demand registration rights. Under the terms of the investors' rights agreement, we will be required, upon the written request of the holders of a majority of our outstanding registrable securities then outstanding, as defined in the investors' rights agreement, that would result in an anticipated aggregate offering price of at least $10.0 million, to file a registration statement and use best efforts to effect the registration of all or a portion of these shares for public resale. We are required to effect only two registrations pursuant to this provision of the investors' rights agreement.

Short-Form Registration Rights

Pursuant to the investors' rights agreement, if we are eligible to file a registration statement on Form S-3, upon the written request of at least 30% of the holders of registrable securities to sell registrable securities at an aggregate offering amount, net of selling expenses, of at least $5.0 million, we will be required to use commercially reasonable efforts to effect a registration of those shares. We are required to effect only two registrations in any 12-month period pursuant to this provision of the investors' rights agreement. The right to have those shares registered on Form S-3 is further subject to other specified conditions and limitations.

Piggyback Registration Rights

Pursuant to the investors' rights agreement, if we register any of our securities either for our own account or for the account of other security holders, the holders of the registrable securities are entitled to include their shares in the registration. Subject to certain exceptions contained in the investors' rights agreement, we and the underwriters may limit the number of shares included in the underwritten offering to the number of shares which we and the underwriters determine in our sole discretion will not jeopardize the success of the offering.

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Indemnification

Our investors' rights agreement contains customary cross-indemnification provisions, under which we are obligated to indemnify holders of registrable securities in the event of material misstatements or omissions in the registration statement attributable to us, and they are obligated to indemnify us for material misstatements or omissions attributable to them.

Expiration of Registration Rights

The demand registration rights, short form registration rights and piggyback registration rights granted under the investors' rights agreement will terminate on (a) the fifth anniversary of our initial public offering, (b) a deemed liquidation event, as defined in the investors' rights agreement, or (c) with respect to any stockholder at such time as such holder's shares may be sold without restriction pursuant to Rule 144 within a three-month period.

Anti-Takeover Effects of our Certificate of Incorporation and By-laws and Delaware Law

Our certificate of incorporation and by-laws include a number of provisions that may have the effect of delaying, deferring or preventing another party from acquiring control of us and encouraging persons considering unsolicited tender offers or other unilateral takeover proposals to negotiate with our board of directors rather than pursue non-negotiated takeover attempts. These provisions include the items described below.

Board Composition and Filling Vacancies

Our certificate of incorporation provides for the division of our board of directors into three classes serving staggered three-year terms, with one class being elected each year. Our certificate of incorporation also provides that directors may be removed only for cause and then only by the affirmative vote of the holders of two-thirds (2/3) or more of the shares then entitled to vote at an election of directors. Furthermore, any vacancy on our board of directors, however occurring, including a vacancy resulting from an increase in the size of our board, may only be filled by the affirmative vote of a majority of our directors then in office, even if less than a quorum. The classification of directors, together with the limitations on removal of directors and treatment of vacancies, has the effect of making it more difficult for stockholders to change the composition of our board of directors.

No Written Consent of Stockholders

Our certificate of incorporation provides that all stockholder actions are required to be taken by a vote of the stockholders at an annual or special meeting, and that stockholders may not take any action by written consent in lieu of a meeting. This requirement may lengthen the amount of time required to take stockholder actions and would prevent the amendment of our amended and restated by-laws, or our by-laws, or removal of directors by our stockholders without holding a meeting of stockholders.

Meetings of Stockholders

Our certificate of incorporation and by-laws provide that only a majority of the members of our board of directors then in office may call special meetings of stockholders and only those matters set forth in the notice of the special meeting may be considered or acted upon at a special meeting of stockholders. Our by-laws limit the business that may be conducted at an annual meeting of stockholders to those matters properly brought before the meeting.

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Advance Notice Requirements

Our by-laws establish advance notice procedures with regard to stockholder proposals relating to the nomination of candidates for election as directors or new business to be brought before meetings of our stockholders. These procedures provide that notice of stockholder proposals must be timely given in writing to our corporate secretary prior to the meeting at which the action is to be taken. Generally, to be timely, notice must be received at our principal executive offices not less than 90 days nor more than 120 days prior to the first anniversary date of the annual meeting for the preceding year. Our by-laws specify the requirements as to form and content of all stockholders' notices. These requirements may preclude stockholders from bringing matters before the stockholders at an annual or special meeting.

Amendment to Certificate of Incorporation and By-laws

Any amendment of our certificate of incorporation must first be approved by a majority of our board of directors, and if required by law or our certificate of incorporation, must thereafter be approved by a majority of the outstanding shares entitled to vote on the amendment and a majority of the outstanding shares of each class entitled to vote thereon as a class, except that the amendment of the provisions relating to stockholder action, board composition, limitation of liability and the amendment of our by-laws and certificate of incorporation must be approved by not less than two-thirds (2/3) of the outstanding shares entitled to vote on the amendment, and not less than two-thirds (2/3) of the outstanding shares of each class entitled to vote thereon as a class. Our by-laws may be amended by the affirmative vote of a majority of the directors then in office, subject to any limitations set forth in the by-laws, and may also be amended by the affirmative vote of at least two-thirds (2/3) of the outstanding shares entitled to vote on the amendment, or, if our board of directors recommends that the stockholders approve the amendment, by the affirmative vote of the majority of the outstanding shares entitled to vote on the amendment, in each case voting together as a single class.

Undesignated Preferred Stock

Our certificate of incorporation provides for 10,000,000 authorized shares of undesignated preferred stock. The existence of authorized but unissued shares of preferred stock may enable our board of directors to discourage an attempt to obtain control of us by means of a merger, tender offer, proxy contest or otherwise. For example, if in the due exercise of its fiduciary obligations, our board of directors were to determine that a takeover proposal is not in the best interests of our stockholders, our board of directors could cause shares of preferred stock to be issued without stockholder approval in one or more private offerings or other transactions that might dilute the voting or other rights of the proposed acquirer or insurgent stockholder or stockholder group. In this regard, our certificate of incorporation grants our board of directors broad power to establish the rights and preferences of authorized and unissued shares of preferred stock. The issuance of shares of preferred stock could decrease the amount of earnings and assets available for distribution to holders of shares of common stock. The issuance may also adversely affect the rights and powers, including voting rights, of these holders and may have the effect of delaying, deterring or preventing a change in control of us.

Choice of Forum

Our by-laws provides that, unless we consent in writing to an alternative forum, the Court of Chancery of the State of Delaware will be the sole and exclusive forum for state law claims for (i) any derivative action or proceeding brought on our behalf, (ii) any action asserting a claim of or based on a breach of a fiduciary duty owed by any of our current or former directors, officers and employees to us or our stockholders, (iii) any action asserting a claim against us or any of our current or former directors, officers, employees or stockholders arising pursuant to any provision of the Delaware General

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Corporation Law, our certificate of incorporation or our by-laws, (iv) any action to interpret, apply, enforce or determine the validity of our certificate of incorporation or our by-laws, or (v) any action asserting a claim that is governed by the internal affairs doctrine, in each case subject to the Court of Chancery having personal jurisdiction over the indispensable parties named as defendants therein (the "Delaware Forum Provision"). The Delaware Forum Provision will not apply to any causes of action arising under the Securities Act or the Exchange Act. Our by-laws further provide that, unless we consent in writing to an alternative forum, the United States District Court for the District of Massachusetts will be the exclusive forum for resolving any complaint asserting a cause of action arising under the Securities Act (the "Federal Forum Provision"). We have chosen the United States District Court for the District of Massachusetts as the exclusive forum for these causes of action because our principal executive offices are located in Cambridge, Massachusetts.

On December 19, 2018, in Sciabacucchi v. Salzberg , C.A. No. 2017-0931-JTL (Del. Ch.), the Court of Chancery of the State of Delaware issued a decision declaring that federal forum selection provisions purporting to require claims under the Securities Act be brought in federal court are ineffective and invalid under Delaware law. On January 17, 2019, the decision was appealed to the Delaware Supreme Court. While the Delaware Supreme Court dismissed the appeal on jurisdictional grounds, we expect that the appeal will be re-filed after the Court of Chancery issues a final judgment. Unless and until the Court of Chancery's decision is reversed by the Delaware Supreme Court or otherwise abrogated, we do not intend to enforce our Federal Forum Provision designating the District of Massachusetts as the exclusive forum for Securities Act claims. In the event that the Delaware Supreme Court affirms the Court of Chancery's decision or otherwise determines that federal forum selection provisions are invalid, our board of directors intends to amend promptly our by-laws to remove our Federal Forum Provision.

We recognize that the Federal Forum Provision may impose additional litigation costs on stockholders who assert the provision is not enforceable and may impose more general additional litigation costs in pursuing any these claims, particularly if the stockholders do not reside in or near the State of Delaware or the Commonwealth of Massachusetts. Additionally, the forum selection clauses in our by-laws may limit our stockholders' ability to obtain a favorable judicial forum for disputes with us. Alternatively, if the Federal Forum Provision is found inapplicable to, or unenforceable in respect of, one or more of the specified types of actions or proceedings, we may incur additional costs associated with resolving such matters in other jurisdictions, which could have an adverse effect on our business, prospects, financial condition or results of operations. The Court of Chancery of the State of Delaware and the United States District Court for the District of Massachusetts may also reach different judgments or results than would other courts, including courts where a stockholder considering an action may be located or would otherwise choose to bring the action, and such judgments may be more or less favorable to us than our stockholders. Although we believe this provision benefits us by providing increased consistency in the application of Delaware law in the types of lawsuits to which it applies, the provision may have the effect of discouraging lawsuits against our directors and officers.

Section 203 of the Delaware General Corporation Law

We are subject to the provisions of Section 203 of the Delaware General Corporation Law. In general, Section 203 prohibits a publicly held Delaware corporation from engaging in a "business combination" with an "interested stockholder" for a three-year period following the time that this stockholder becomes an interested stockholder, unless the business combination is approved in a prescribed manner. Under Section 203, a business combination between a corporation and an interested stockholder is prohibited unless it satisfies one of the following conditions:

•: before the stockholder became interested, our board of directors approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;

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•: upon consummation of the transaction which resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding for purposes of determining the voting stock outstanding, shares owned by persons who are directors and also officers, and employee stock plans, in some instances, but not the outstanding voting stock owned by the interested stockholder; or
•: at or after the time the stockholder became interested, the business combination was approved by our board of directors and authorized at an annual or special meeting of the stockholders by the affirmative vote of at least two-thirds (2/3) of the outstanding voting stock which is not owned by the interested stockholder.

Section 203 defines a business combination to include:

•: any merger or consolidation involving the corporation and the interested stockholder;
•: any sale, transfer, lease, pledge or other disposition involving the interested stockholder of 10% or more of the assets of the corporation;
•: subject to exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder;
•: subject to exceptions, any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder; and
•: the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.

In general, Section 203 defines an interested stockholder as any entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by the entity or person.

Nasdaq Global Select Market Listing

Our common stock is listed on The Nasdaq Global Select Market under the symbol "RUBY".

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is American Stock Transfer & Trust Company, LLC. The transfer agent and registrar's address is 6201 15 ^th Avenue, Brooklyn, NY 11219 and its telephone number is (800) 937-5449.

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DESCRIPTION OF DEBT SECURITIES

This section describes the general terms and provisions of our debt securities that we may issue from time to time. We may issue debt securities, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. While the terms we have summarized below will apply generally to any future debt securities we may offer under this prospectus, the applicable prospectus supplement or free writing prospectus will describe the specific terms of any debt securities offered through that prospectus supplement or free writing prospectus. The terms of any debt securities we offer under a prospectus supplement or free writing prospectus may differ from the terms we describe below. Unless the context requires otherwise, whenever we refer to the "indentures," we also are referring to any supplemental indentures that specify the terms of a particular series of debt securities.

We will issue any senior debt securities under the senior indenture that we will enter into with the trustee named in the senior indenture. We will issue any subordinated debt securities under the subordinated indenture that we will enter into with the trustee named in the subordinated indenture. We have filed forms of these documents as exhibits to the registration statement, of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.

The indentures will be qualified under the Trust Indenture Act of 1939, as amended, or the Trust Indenture Act. We use the term "trustee" to refer to either the trustee under the senior indenture or the trustee under the subordinated indenture, as applicable.

The following summaries of material provisions of the senior debt securities, the subordinated debt securities and the indentures are subject to, and qualified in their entirety by reference to, all of the provisions of the indenture applicable to a particular series of debt securities. We urge you to read the applicable prospectus supplement or free writing prospectus and any related free writing prospectuses related to the debt securities that we may offer under this prospectus, as well as the complete applicable indenture that contains the terms of the debt securities. Except as we may otherwise indicate, the terms of the senior indenture and the subordinated indenture are identical.

General

We will describe in the applicable prospectus supplement or free writing prospectus the terms of the series of debt securities being offered, including:

•: the title;
•: the principal amount being offered, and if a series, the total amount authorized and the total amount outstanding;
•: any limit on the amount that may be issued;
•: whether or not we will issue the series of debt securities in global form, and, if so, the terms and who the depository will be;
•: the maturity date;
•: whether and under what circumstances, if any, we will pay additional amounts on any debt securities held by a person who is not a United States person for tax purposes, and whether we can redeem the debt securities if we have to pay such additional amounts;
•: the annual interest rate, which may be fixed or variable, or the method for determining the rate and the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;

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•

whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;

•

the terms of the subordination of any series of subordinated debt;

•

the place where payments will be payable;

•

restrictions on transfer, sale or other assignment, if any;

•

our right, if any, to defer payment of interest and the maximum length of any such deferral period;

•

the date, if any, after which, the conditions upon which, and the price at which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemption provisions;

•

the date, if any, on which, and the price at which we are obligated, pursuant to any mandatory sinking fund or analogous fund provisions or otherwise, to redeem, or at the holder's option, to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;

•

whether the indenture will restrict our ability or the ability of our subsidiary to:

•: incur additional indebtedness;
•: issue additional securities;
•: create liens;
•: pay dividends or make distributions in respect of our capital stock or the capital stock of our subsidiary;
•: redeem capital stock;
•: place restrictions on our subsidiary's ability to pay dividends, make distributions or transfer assets;
•: make investments or other restricted payments;
•: sell or otherwise dispose of assets;
•: enter into sale-leaseback transactions;
•: engage in transactions with stockholders or affiliates;
•: issue or sell stock of our subsidiary; or
•: effect a consolidation or merger;

•

whether the indenture will require us to maintain any interest coverage, fixed charge, cash flow-based, asset-based or other financial ratios;

•

a discussion of certain material or special United States federal income tax considerations applicable to the debt securities;

•

information describing any book-entry features;

•

provisions for a sinking fund purchase or other analogous fund, if any;

•

the applicability of the provisions in the indenture on discharge;

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•: whether the debt securities are to be offered at a price such that they will be deemed to be offered at an "original issue discount" as defined in paragraph (a) of Section 1273 of the Internal Revenue Code of 1986, as amended;
•: the denominations in which we will issue the series of debt securities, if other than denominations of $1,000 and any integral multiple thereof;
•: the currency of payment of debt securities if other than U.S. dollars and the manner of determining the equivalent amount in U.S. dollars; and
•: any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, including any additional events of default or covenants provided with respect to the debt securities, and any terms that may be required by us or advisable under applicable laws or regulations or advisable in connection with the marketing of the debt securities.

Conversion or Exchange Rights

We will set forth in the applicable prospectus supplement or free writing prospectus the terms on which a series of debt securities may be convertible into or exchangeable for our common stock, our preferred stock or other securities (including securities of a third-party). We will include provisions as to whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock, our preferred stock or other securities (including securities of a third-party) that the holders of the series of debt securities receive would be subject to adjustment.

Consolidation, Merger or Sale

Unless we provide otherwise in the prospectus supplement or free writing prospectus applicable to a particular series of debt securities, the indentures will not contain any covenant that restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of all or substantially all of our assets. However, any successor to or acquirer of such assets must assume all of our obligations under the indentures or the debt securities, as appropriate. If the debt securities are convertible into or exchangeable for other securities of ours or securities of other entities, the person with whom we consolidate or merge or to whom we sell all of our property must make provisions for the conversion of the debt securities into securities that the holders of the debt securities would have received if they had converted the debt securities before the consolidation, merger or sale.

Events of Default Under the Indenture

Unless we provide otherwise in the prospectus supplement or free writing prospectus applicable to a particular series of debt securities, the following are events of default under the indentures with respect to any series of debt securities that we may issue:

•: if we fail to pay interest when due and payable and our failure continues for 90 days and the time for payment has not been extended;
•: if we fail to pay the principal, premium or sinking fund payment, if any, when due and payable at maturity, upon redemption or repurchase or otherwise, and the time for payment has not been extended;
•: if we fail to observe or perform any other covenant contained in the debt securities or the indentures, other than a covenant specifically relating to another series of debt securities, and our failure continues for 90 days after we receive notice from the trustee or holders of at least 25% in aggregate principal amount of the outstanding debt securities of the applicable series; and
•: if specified events of bankruptcy, insolvency or reorganization occur.

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We will describe in each applicable prospectus supplement or free writing prospectus any additional events of default relating to the relevant series of debt securities.

If an event of default with respect to debt securities of any series occurs and is continuing, other than an event of default specified in the last bullet point above, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series, by notice to us in writing, and to the trustee if notice is given by such holders, may declare the unpaid principal, premium, if any, and accrued interest, if any, due and payable immediately. If an event of default specified in the last bullet point above occurs with respect to us, the unpaid principal, premium, if any, and accrued interest, if any, of each issue of debt securities then outstanding shall be due and payable without any notice or other action on the part of the trustee or any holder.

The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or events of default regarding payment of principal, premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any waiver shall cure the default or event of default.

Subject to the terms of the indentures, if an event of default under an indenture shall occur and be continuing, the trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the trustee reasonable indemnity or security satisfactory to it against any loss, liability or expense. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities of that series, provided that:

•: the direction so given by the holder is not in conflict with any law or the applicable indenture; and
•: subject to its duties under the Trust Indenture Act, the trustee need not take any action that might involve it in personal liability or might be unduly prejudicial to the holders not involved in the proceeding.

A holder of the debt securities of any series will have the right to institute a proceeding under the indentures or to appoint a receiver or trustee, or to seek other remedies if:

•: the holder has given written notice to the trustee of a continuing event of default with respect to that series;
•: the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series have made written request, and such holders have offered reasonable indemnity to the trustee or security satisfactory to it against any loss, liability or expense or to be incurred in compliance with instituting the proceeding as trustee; and
•: the trustee does not institute the proceeding, and does not receive from the holders of a majority in aggregate principal amount of the outstanding debt securities of that series other conflicting directions within 90 days after the notice, request and offer.

These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities, or other defaults that may be specified in the applicable prospectus supplement or free writing prospectus.

We will periodically file statements with the trustee regarding our compliance with specified covenants in the indentures.

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Modification of Indenture; Waiver

Subject to the terms of the indenture for any series of debt securities that we may issue, we and the trustee may change an indenture without the consent of any holders with respect to the following specific matters:

•: to fix any ambiguity, defect or inconsistency in the indenture;
•: to comply with the provisions described above under "Description of Our Debt Securities—Consolidation, Merger or Sale;"
•: to comply with any requirements of the SEC in connection with the qualification of any indenture under the Trust Indenture Act;
•: to add to, delete from or revise the conditions, limitations, and restrictions on the authorized amount, terms, or purposes of issue, authentication and delivery of debt securities, as set forth in the indenture;
•: to provide for the issuance of and establish the form and terms and conditions of the debt securities of any series as provided under "Description of Our Debt Securities—General," to establish the form of any certifications required to be furnished pursuant to the terms of the indenture or any series of debt securities, or to add to the rights of the holders of any series of debt securities;
•: to evidence and provide for the acceptance of appointment hereunder by a successor trustee;
•: to provide for uncertificated debt securities and to make all appropriate changes for such purpose;
•: to add to our covenants such new covenants, restrictions, conditions or provisions for the benefit of the holders, to make the occurrence, or the occurrence and the continuance, of a default in any such additional covenants, restrictions, conditions or provisions an event of default or to surrender any right or power conferred to us in the indenture; or
•: to change anything that does not materially adversely affect the interests of any holder of debt securities of any series.

In addition, under the indentures, the rights of holders of a series of debt securities may be changed by us and the trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, subject to the terms of the indenture for any series of debt securities that we may issue or as otherwise provided in the prospectus supplement or free writing prospectus applicable to a particular series of debt securities, we and the trustee may make the following changes only with the consent of each holder of any outstanding debt securities affected:

•: extending the stated maturity of the series of debt securities;
•: reducing the principal amount, reducing the rate of or extending the time of payment of interest, or reducing any premium payable upon the redemption or repurchase of any debt securities; or
•: reducing the percentage of debt securities, the holders of which are required to consent to any amendment, supplement, modification or waiver.

Discharge

Each indenture provides that, subject to the terms of the indenture and any limitation otherwise provided in the prospectus supplement or free writing prospectus applicable to a particular series of

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debt securities, we can elect to be discharged from our obligations with respect to one or more series of debt securities, except for specified obligations, including obligations to:

•: register the transfer or exchange of debt securities of the series;
•: replace stolen, lost or mutilated debt securities of the series;
•: maintain paying agencies;
•: hold monies for payment in trust;
•: recover excess money held by the trustee;
•: compensate and indemnify the trustee; and
•: appoint any successor trustee.

In order to exercise our rights to be discharged, we must deposit with the trustee money or government obligations sufficient to pay all the principal of, any premium and interest on, the debt securities of the series on the dates payments are due.

Form, Exchange and Transfer

We will issue the debt securities of each series only in fully registered form without coupons and, unless we otherwise specify in the applicable prospectus supplement or free writing prospectus, in denominations of $1,000 and any integral multiple thereof. The indentures provide that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company or another depository named by us and identified in a prospectus supplement or free writing prospectus with respect to that series.

At the option of the holder, subject to the terms of the indentures and the limitations applicable to global securities described in the applicable prospectus supplement or free writing prospectus, the holder of the debt securities of any series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

Subject to the terms of the indentures and the limitations applicable to global securities set forth in the applicable prospectus supplement or free writing prospectus, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange, we will make no service charge for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.

We will name in the applicable prospectus supplement or free writing prospectus the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series. If we elect to redeem the debt securities of any series, we will not be required to:

•: issue, register the transfer of, or exchange any debt securities of that series during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of any debt securities that may be selected for redemption and ending at the close of business on the day of the mailing; or
•: register the transfer of or exchange any debt securities so selected for redemption, in whole or in part, except the unredeemed portion of any debt securities we are redeeming in part.

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Information Concerning the Trustee

The trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of default under an indenture, the trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs.

Subject to this provision, the trustee is under no obligation to exercise any of the powers given it by the indentures at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.

Payment and Paying Agents

Unless we otherwise indicate in the applicable prospectus supplement or free writing prospectus, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.

We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement or free writing prospectus, we will make interest payments by check that we will mail to the holder or by wire transfer to certain holders. Unless we otherwise indicate in the applicable prospectus supplement or free writing prospectus, we will designate the corporate trust office of the trustee as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement or free writing prospectus any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the trustee for the payment of the principal of or any premium or interest on any debt securities that remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the debt security thereafter may look only to us for payment thereof.

Governing Law

The indentures and the debt securities will be governed by and construed in accordance with the laws of the State of New York, except to the extent that the Trust Indenture Act is applicable.

Ranking of Debt Securities

The subordinated debt securities will be subordinate and junior in priority of payment to certain of our other indebtedness to the extent described in a prospectus supplement or free writing prospectus. The subordinated indenture does not limit the amount of subordinated debt securities that we may issue. It also does not limit us from issuing any other secured or unsecured debt.

The senior debt securities will rank equally in right of payment to all our other senior unsecured debt. The senior indenture does not limit the amount of senior debt securities that we may issue. It also does not limit us from issuing any other secured or unsecured debt.

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DESCRIPTION OF WARRANTS

The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the warrants that we may offer under this prospectus and the related warrant agreements and warrant certificates. While the terms summarized below will apply generally to any warrants that we may offer, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. If we indicate in the prospectus supplement, the terms of any warrants offered under that prospectus supplement may differ from the terms described below. Specific warrant agreements will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement, which includes this prospectus.

General

We may issue warrants for the purchase of common stock, preferred stock and/or debt securities in one or more series. We may issue warrants independently or together with common stock, preferred stock and/or debt securities, and the warrants may be attached to or separate from these securities.

We will evidence each series of warrants by warrant certificates that we will issue under a separate warrant agreement. We will enter into the warrant agreement with a warrant agent. We will indicate the name and address of the warrant agent in the applicable prospectus supplement relating to a particular series of warrants.

We will describe in the applicable prospectus supplement the terms of the series of warrants, including:

•: the offering price and aggregate number of warrants offered;
•: the currency for which the warrants may be purchased;
•: if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;
•: if applicable, the date on and after which the warrants and the related securities will be separately transferable;
•: in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant and the price at, and currency in which, this principal amount of debt securities may be purchased upon such exercise;
•: in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which these shares may be purchased upon such exercise;
•: the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreement and the warrants;
•: the terms of any rights to redeem or call the warrants;
•: any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;
•: the periods during which, and places at which, the warrants are exercisable;
•: the manner of exercise;
•: the dates on which the right to exercise the warrants will commence and expire;
•: the manner in which the warrant agreement and warrants may be modified;
•: federal income tax consequences of holding or exercising the warrants;
•: the terms of the securities issuable upon exercise of the warrants; and
•: any other specific terms, preferences, rights or limitations of or restrictions on the warrants.

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DESCRIPTION OF UNITS

We may issue units comprised of shares of common stock, shares of preferred stock, debt securities and warrants in any combination. We may issue units in such amounts and in as many distinct series as we wish. This section outlines certain provisions of the units that we may issue. If we issue units, they will be issued under one or more unit agreements to be entered into between us and a bank or other financial institution, as unit agent. The information described in this section may not be complete in all respects and is qualified entirely by reference to the unit agreement with respect to the units of any particular series. The specific terms of any series of units offered will be described in the applicable prospectus supplement. If so described in a particular supplement, the specific terms of any series of units may differ from the general description of terms presented below. We urge you to read any prospectus supplement related to any series of units we may offer, as well as the complete unit agreement and unit certificate that contain the terms of the units. If we issue units, forms of unit agreements and unit certificates relating to such units will be incorporated by reference as exhibits to the registration statement, which includes this prospectus.

Each unit that we may issue will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date. The applicable prospectus supplement may describe:

•: the designation and terms of the units and of the securities comprising the units, including whether and under what circumstances those securities may be held or transferred separately;
•: any provisions of the governing unit agreement;
•: the price or prices at which such units will be issued;
•: the applicable United States federal income tax considerations relating to the units;
•: any provisions for the issuance, payment, settlement, transfer or exchange of the units or of the securities comprising the units; and
•: any other terms of the units and of the securities comprising the units.

The provisions described in this section, as well as those described under "Description of Capital Stock," "Description of Debt Securities" and "Description of Warrants" will apply to the securities included in each unit, to the extent relevant and as may be updated in any prospectus supplements.

Issuance in Series

We may issue units in such amounts and in as many distinct series as we wish. This section summarizes terms of the units that apply generally to all series. Most of the financial and other specific terms of a particular series of units will be described in the applicable prospectus supplement.

Unit Agreements

We will issue the units under one or more unit agreements to be entered into between us and a bank or other financial institution, as unit agent. We may add, replace or terminate unit agents from time to time. We will identify the unit agreement under which each series of units will be issued and the unit agent under that agreement in the applicable prospectus supplement.

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The following provisions will generally apply to all unit agreements unless otherwise stated in the applicable prospectus supplement:

Modification without Consent

We and the applicable unit agent may amend any unit or unit agreement without the consent of any holder:

•: to cure any ambiguity, including modifying any provisions of the governing unit agreement that differ from those described below;
•: to correct or supplement any defective or inconsistent provision; or
•: to make any other change that we believe is necessary or desirable and will not adversely affect the interests of the affected holders in any material respect.

We do not need any approval to make changes that affect only units to be issued after the changes take effect. We may also make changes that do not adversely affect a particular unit in any material respect, even if they adversely affect other units in a material respect. In those cases, we do not need to obtain the approval of the holder of the unaffected unit; we need only obtain any required approvals from the holders of the affected units.

Modification with Consent

We may not amend any particular unit or a unit agreement with respect to any particular unit unless we obtain the consent of the holder of that unit, if the amendment would:

•: impair any right of the holder to exercise or enforce any right under a security included in the unit if the terms of that security require the consent of the holder to any changes that would impair the exercise or enforcement of that right; or
•: reduce the percentage of outstanding units or any series or class the consent of whose holders is required to amend that series or class, or the applicable unit agreement with respect to that series or class, as described below.

Any other change to a particular unit agreement and the units issued under that agreement would require the following approval:

•: If the change affects only the units of a particular series issued under that agreement, the change must be approved by the holders of a majority of the outstanding units of that series; or
•: If the change affects the units of more than one series issued under that agreement, it must be approved by the holders of a majority of all outstanding units of all series affected by the change, with the units of all the affected series voting together as one class for this purpose.

These provisions regarding changes with majority approval also apply to changes affecting any securities issued under a unit agreement, as the governing document.

In each case, the required approval must be given by written consent.

Unit Agreements Will Not Be Qualified under Trust Indenture Act

No unit agreement will be qualified as an indenture, and no unit agent will be required to qualify as a trustee, under the Trust Indenture Act. Therefore, holders of units issued under unit agreements will not have the protections of the Trust Indenture Act with respect to their units.

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Mergers and Similar Transactions Permitted; No Restrictive Covenants or Events of Default

The unit agreements will not restrict our ability to merge or consolidate with, or sell our assets to, another corporation or other entity or to engage in any other transactions. If at any time we merge or consolidate with, or sell our assets substantially as an entirety to, another corporation or other entity, the successor entity will succeed to and assume our obligations under the unit agreements. We will then be relieved of any further obligation under these agreements.

The unit agreements will not include any restrictions on our ability to put liens on our assets, nor will they restrict our ability to sell our assets. The unit agreements also will not provide for any events of default or remedies upon the occurrence of any events of default.

Governing Law

The unit agreements and the units will be governed by Delaware law.

Form, Exchange and Transfer

We will issue each unit in global—i.e., book-entry—form only. Units in book-entry form will be represented by a global security registered in the name of a depositary, which will be the holder of all the units represented by the global security. Those who own beneficial interests in a unit will do so through participants in the depositary's system, and the rights of these indirect owners will be governed solely by the applicable procedures of the depositary and its participants. We will describe book-entry securities, and other terms regarding the issuance and registration of the units in the applicable prospectus supplement.

Each unit and all securities comprising the unit will be issued in the same form.

If we issue any units in registered, non-global form, the following will apply to them.

The units will be issued in the denominations stated in the applicable prospectus supplement. Holders may exchange their units for units of smaller denominations or combined into fewer units of larger denominations, as long as the total amount is not changed.

•: Holders may exchange or transfer their units at the office of the unit agent. Holders may also replace lost, stolen, destroyed or mutilated units at that office. We may appoint another entity to perform these functions or perform them ourselves.
•: Holders will not be required to pay a service charge to transfer or exchange their units, but they may be required to pay for any tax or other governmental charge associated with the transfer or exchange. The transfer or exchange, and any replacement, will be made only if our transfer agent is satisfied with the holder's proof of legal ownership. The transfer agent may also require an indemnity before replacing any units.
•: If we have the right to redeem, accelerate or settle any units before their maturity, and we exercise our right as to less than all those units or other securities, we may block the exchange or transfer of those units during the period beginning 15 days before the day we mail the notice of exercise and ending on the day of that mailing, in order to freeze the list of holders to prepare the mailing. We may also refuse to register transfers of or exchange any unit selected for early settlement, except that we will continue to permit transfers and exchanges of the unsettled portion of any unit being partially settled. We may also block the transfer or exchange of any unit in this manner if the unit includes securities that are or may be selected for early settlement.

Only the depositary will be entitled to transfer or exchange a unit in global form, since it will be the sole holder of the unit.

Payments and Notices

In making payments and giving notices with respect to our units, we will follow the procedures as described in the applicable prospectus supplement.

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PLAN OF DISTRIBUTION

We may sell the securities offered through this prospectus and any accompanying prospectus supplement, if required, in any of the following ways: (1) to or through underwriters or dealers, (2) directly to purchasers, including our affiliates, (3) through agents, or (4) through a combination of any these methods. The securities may be distributed at a fixed price or prices, which may be changed, market prices prevailing at the time of sale, prices related to the prevailing market prices, or negotiated prices, either:

•: on or through the facilities of The Nasdaq Global Select Market or any other securities exchange or quotation or trading service on which such securities may be listed, quoted or traded at the time of sale; and/or
•: to or through a market maker otherwise than on The Nasdaq Global Select Market or such other securities exchanges or quotation or trading services.

In addition, we may issue the securities as a dividend or distribution or in a subscription rights offering to our existing security holders.

We may directly solicit offers to purchase securities, or agents may be designated to solicit such offers. In the prospectus supplement relating to such offering, we will name any agent that could be viewed as an underwriter under the Securities Act and describe any commissions that we must pay to any such agent. Any such agent will be acting on a best efforts basis for the period of its appointment or, if indicated in the applicable prospectus supplement, on a firm commitment basis. This prospectus may be used in connection with any offering of our securities through any of these methods or other methods described in the applicable prospectus supplement.

Each prospectus supplement will describe the method of distribution of the securities and any applicable restrictions.

The prospectus supplement with respect to the securities of a particular series will describe the terms of the offering of the securities, including the following:

•: the name of the agent or any underwriters;
•: the public offering or purchase price;
•: any discounts and commissions to be allowed or paid to the agent or underwriters;
•: all other items constituting underwriting compensation;
•: any discounts and commissions to be allowed or paid to dealers; and
•: any exchanges on which the securities will be listed.

If any underwriters or agents are used in the sale of the securities in respect of which this prospectus is delivered, we will enter into an underwriting agreement, sales agreement or other agreement with them at the time of sale to them, and we will set forth in the prospectus supplement relating to such offering the names of the underwriters or agents and the terms of the related agreement with them.

In connection with the offering of securities, we may grant to the underwriters an option to purchase additional securities with an additional underwriting commission, as may be set forth in the accompanying prospectus supplement. If we grant any such option, the terms of such option will be set forth in the prospectus supplement for such securities.

If a dealer is used in the sale of the securities in respect of which the prospectus is delivered, we will sell such securities to the dealer, as principal. The dealer, who may be deemed to be an

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"underwriter" as that term is defined in the Securities Act, may then resell such securities to the public at varying prices to be determined by such dealer at the time of resale.

If we offer securities in a subscription rights offering to our existing security holders, we may enter into a standby underwriting agreement with dealers, acting as standby underwriters. We may pay the standby underwriters a commitment fee for the securities they commit to purchase on a standby basis. If we do not enter into a standby underwriting arrangement, we may retain a dealer-manager to manage a subscription rights offering for us.

Agents, underwriters, dealers and other persons may be entitled under agreements which they may enter into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, and may be customers of, engage in transactions with or perform services for us in the ordinary course of business.

If so indicated in the applicable prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by certain institutions to purchase securities from us pursuant to delayed delivery contracts providing for payment and delivery on the date stated in the prospectus supplement. Each contract will be for an amount not less than, and the aggregate amount of securities sold pursuant to such contracts shall not be less nor more than, the respective amounts stated in the prospectus supplement. Institutions with whom the contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutions, but shall in all cases be subject to our approval. Delayed delivery contracts will not be subject to any conditions except that:

•: the purchase by an institution of the securities covered under that contract shall not at the time of delivery be prohibited under the laws of the jurisdiction to which that institution is subject; and
•: if the securities are also being sold to underwriters acting as principals for their own account, the underwriters shall have purchased such securities not sold for delayed delivery. The underwriters and other persons acting as our agents will not have any responsibility in respect of the validity or performance of delayed delivery contracts.

Offered securities may also be offered and sold, if so indicated in the prospectus supplement, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more remarketing firms, acting as principals for their own accounts or as agents for us. Any remarketing firm will be identified and the terms of its agreement, if any, with us and its compensation will be described in the applicable prospectus supplement. Remarketing firms may be deemed to be underwriters in connection with their remarketing of offered securities.

Certain agents, underwriters and dealers, and their associates and affiliates, may be customers of, have borrowing relationships with, engage in other transactions with, or perform services, including investment banking services, for us or one or more of our respective affiliates in the ordinary course of business.

In order to facilitate the offering of the securities, any underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the securities or any other securities the prices of which may be used to determine payments on such securities. Specifically, any underwriters may over allot in connection with the offering, creating a short position for their own accounts. In addition, to cover overallotments or to stabilize the price of the securities or of any such other securities, the underwriters may bid for, and purchase, the securities or any such other securities in the open market. Finally, in any offering of the securities through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allowed to an underwriter or a dealer for distributing the securities in the offering if the syndicate repurchases previously distributed securities in transactions to cover

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syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of the securities above independent market levels. Any such underwriters are not required to engage in these activities and may end any of these activities at any time.

We may engage in at the market offerings into an existing trading market in accordance with Rule 415(a)(4) under the Securities Act. In addition, we may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement so indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be named in the applicable prospectus supplement (or a post-effective amendment). In addition, we may otherwise loan or pledge securities to a financial institution or other third party that in turn may sell the securities short using this prospectus and an applicable prospectus supplement. Such financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

Under Rule 15c6-1 of the Exchange Act, trades in the secondary market generally are required to settle in two business days, unless the parties to any such trade expressly agree otherwise. The applicable prospectus supplement may provide that the original issue date for your securities may be more than two scheduled business days after the trade date for your securities. Accordingly, in such a case, if you wish to trade securities on any date prior to the second business day before the original issue date for your securities, you will be required, by virtue of the fact that your securities initially are expected to settle in more than two scheduled business days after the trade date for your securities, to make alternative settlement arrangements to prevent a failed settlement.

The securities may be new issues of securities and may have no established trading market. The securities may or may not be listed on a national securities exchange. We can make no assurance as to the liquidity of or the existence of trading market for any of the securities.

The specific terms of any lock-up provisions in respect of any given offering will be described in the applicable prospectus supplement.

The underwriters, dealers and agents may engage in transactions with us, or perform services for us, in the ordinary course of business for which they receive compensation.

The anticipated date of delivery of offered securities will be set forth in the applicable prospectus supplement relating to each offer.

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LEGAL MATTERS

Certain legal matters in connection with this offering will be passed upon for us by Goodwin Procter LLP, Boston, Massachusetts. Any underwriters will also be advised about the validity of the securities and other legal matters by their own counsel, which will be named in the prospectus supplement.

EXPERTS

The financial statements incorporated in this prospectus by reference to the Annual Report on Form 10-K for the year ended December 31, 2018 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

WHERE YOU CAN FIND MORE INFORMATION

This prospectus is part of a registration statement that we have filed with the SEC. Certain information in the registration statement has been omitted from this prospectus in accordance with the rules of the SEC. We are subject to the information requirements of the Exchange Act and, in accordance therewith, file annual, quarterly and special reports, proxy statements and other information with the SEC. These documents may be accessed through the SEC's electronic data gathering, analysis and retrieval system, or EDGAR, via electronic means, including the SEC's home page on the Internet ( www.sec.gov ).

We have the authority to designate and issue more than one class or series of stock having various preferences, conversion and other rights, voting powers, restrictions, limitations as to dividends, qualifications, and terms and conditions of redemption. See "Description of Capital Stock." We will furnish a full statement of the relative rights and preferences of each class or series of our stock which has been so designated and any restrictions on the ownership or transfer of our stock to any shareholder upon request and without charge. Written requests for such copies should be directed to Investor Relations, Rubius Therapeutics, Inc., 399 Binney Street, Suite 300, Cambridge, Massachusetts 02139, and our website is located at www.rubiustx.com. Information contained on our website is not incorporated by reference into this prospectus and, therefore, is not part of this prospectus or any accompanying prospectus supplement.

INCORPORATION BY REFERENCE

The SEC allows us to incorporate by reference the information and reports we file with it, which means that we can disclose important information to you by referring you to these documents. The information incorporated by reference is an important part of this prospectus, and information that we file later with the SEC will automatically update and supersede the information already incorporated by reference. We are incorporating by reference the documents listed below, which we have already filed with the SEC, and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, including all filings made after the date of the filing of this registration statement and prior to the effectiveness of this registration statement, except as to any portion of any future report or document that is not deemed filed under such provisions, until we sell all of the securities:

•: our Annual Report on Form 10-K for the year ended December 31, 2018, filed with the SEC on March 28, 2019;
•: our Annual Report on Form 10-K/A (Amendment No. 1) for the year ended December 31, 2018, filed with the SEC on May 15, 2019;

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•: the information specifically incorporated by reference into our Annual Report on Form 10-K for the year ended December 31, 2018 from our definitive proxy statement on Schedule 14A (other than information furnished rather than filed), which was filed with the SEC on April 12, 2019;
•: our Quarterly Report on Form 10-Q for the quarter ended March 31, 2019, filed with the SEC on May 15, 2019;
•: our Current Reports on Form 8-K filed with the SEC on January 22, 2019 , March 11, 2019 , March 25, 2019 , May 15, 2019 and May 23, 2019 (in each case, except for information contained therein which is furnished rather than filed); and
•: the description of our common stock contained in our registration statement on Form 8-A filed with the SEC on July 13, 2018, including any amendments or reports filed for the purposes of updating this description.

Upon request, either orally or in writing, we will provide, without charge, to each person, including any beneficial owner, to whom a copy of this prospectus is delivered, a copy of the documents incorporated by reference into this prospectus but not delivered with the prospectus. You may request a copy of these filings, and any exhibits we have specifically incorporated by reference as an exhibit in this prospectus, at no cost by writing us at the following address: Investor Relations Department, Rubius Therapeutics, Inc., 399 Binney Street, Suite 300, Cambridge, Massachusetts 02139, (617) 679-9600.

This prospectus is part of a registration statement we filed with the SEC. We have incorporated exhibits into this registration statement. You should read the exhibits carefully for provisions that may be important to you.

You should rely only on the information incorporated by reference or provided in this prospectus or any prospectus supplement. We have not authorized anyone to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information in this prospectus or in the documents incorporated by reference is accurate as of any date other than the date on the front of this prospectus or those documents.

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$450,000,000

Common Stock
Preferred Stock
Debt Securities
Warrants
Units

PROSPECTUS

, 2019

We have not authorized any dealer, salesperson or other person to give any information or represent anything not contained in this prospectus. You must not rely on any unauthorized information. If anyone provides you with different or inconsistent information, you should not rely on it. This prospectus does not offer to sell any securities in any jurisdiction where it is unlawful. Neither the delivery of this prospectus, nor any sale made hereunder, shall create any implication that the information in this prospectus is correct after the date hereof.

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The information in this prospectus supplement is not complete and may be changed. These securities may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus supplement is not an offer to sell nor does it seek an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.


PROSPECTUS SUPPLEMENT (Subject to Completion)		Dated August 1, 2019

Up to $100,000,000

Common Stock

We have entered into a distribution agreement, or the Distribution Agreement, with J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC (which we refer to collectively as the "Sales Agents," and each individually as a "Sales Agent"), relating to shares of our common stock, par value $0.001 per share, offered by this prospectus supplement. In accordance with the terms of the Distribution Agreement, we may offer and sell shares of our common stock having an aggregate offering price of up to $100,000,000 from time to time through the Sales Agents. Sales of the shares of common stock, if any, may be made on The Nasdaq Global Select Market at market prices and such other sales as agreed upon by us and the Sales Agents, as the case may be.

Our common stock is listed on The Nasdaq Global Select Market under the symbol "RUBY". On July 29, 2019, the closing price of our common stock, as reported on The Nasdaq Global Select Market, was $14.59 per share.

Sales of our common stock, if any, under this prospectus supplement will be made in sales deemed to be "at the market offerings" as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, or the Securities Act. The Sales Agents are not required to sell any specific number or dollar amount of securities, but will use commercially reasonable efforts to sell on our behalf all of the shares of common stock requested to be sold by us, consistent with their normal trading and sales practices, on mutually agreed terms between the Sales Agents and us. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.

The Sales Agents will be entitled to compensation at a fixed commission rate of 3.0% of the gross sales price of common stock sold under the Distribution Agreement. See "Plan of Distribution" beginning on page S-22 for additional information regarding the compensation to be paid to the Sales Agents. In connection with the sale of the common stock on our behalf, the Sales Agents will be deemed to be "underwriters" within the meaning of the Securities Act and the compensation of the Sales Agents will be deemed to be underwriting commissions or discounts. We have also agreed to provide indemnification and contribution to the Sales Agents with respect to certain liabilities, including liabilities under the Securities Act or the Securities Exchange Act of 1934, as amended, or the Exchange Act.

We are an emerging growth company as that term is used in the Jumpstart Our Business Startups Act of 2012 and, as such, have elected to comply with certain reduced public company reporting requirements for this prospectus supplement and future filings.

Investing in our common stock involves a high degree of risk. You should review carefully the risks and uncertainties referenced under the heading "Risk Factors" on page S-7 of this prospectus supplement and in the documents that are incorporated by reference into this prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.


J.P. Morgan		Jefferies		SVB Leerink

The date of this prospectus supplement is , 2019

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		Page

About this Prospectus Supplement			S-1
Prospectus Supplement Summary			S-3
The Offering			S-5
Risk Factors			S-7
Cautionary Statement Regarding Forward-Looking Statements			S-13
Use of Proceeds			S-15
Dividend Policy			S-15
Dilution			S-16
Material U.S. Federal Income Tax Considerations for Non-U.S. Holders			S-18
Plan of Distribution			S-22
Legal Matters			S-23
Experts			S-23
Where You Can Find More Information			S-23
Incorporation by Reference			S-24

We are responsible for the information contained and incorporated by reference in this prospectus supplement and in any related free writing prospectus we prepare or authorize. We have not authorized anyone to give you any other information, and we take no responsibility for any other information that others may give you. If you are in a jurisdiction where offers to sell, or solicitations of offers to purchase, the securities offered by this documentation are unlawful, or if you are a person to whom it is unlawful to direct these types of activities, then the offer presented in this document does not extend to you. The information contained in this document speaks only as of the date of this document, unless the information specifically indicates that another date applies. Our business, financial condition, results of operations and prospects may have changed since those dates.

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ABOUT THIS PROSPECTUS SUPPLEMENT

This prospectus supplement is part of a shelf registration statement on Form S-3 that we filed with the Securities and Exchange Commission ("SEC"). Under the shelf registration process, we may offer shares of our common stock having an aggregate offering price of up to $100,000,000 from time to time under this prospectus supplement at prices and on terms to be determined by market conditions at the time of the offering.

If the information contained in this prospectus supplement differs or varies from the information contained in any document incorporated by reference herein that was filed with the SEC before the date of this prospectus supplement, you should rely on the information set forth in this prospectus supplement. If any statement in one of these documents is inconsistent with a statement in another document having a later date (for example, a subsequently filed document deemed incorporated by reference in this prospectus supplement), the statement in the document having the later date modifies or supersedes the earlier statement. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to constitute a part of this prospectus supplement.

You should rely only on the information contained or incorporated by reference in this prospectus supplement. We have not, and the Sales Agents have not, authorized anyone to provide you with information that is in addition to or different from that contained or incorporated by reference in this prospectus supplement or contained in any permitted free writing prospectuses we have authorized for use in connection with this offering. We and the Sales Agents take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may provide.

The information contained in this prospectus supplement and the documents incorporated by reference herein is accurate only as of their respective dates, regardless of the time of delivery of any such document or the time of any sale of our common stock. Our business, financial condition, results of operations and prospects may have changed since those dates. It is important for you to read and consider all information contained or incorporated by reference in this prospectus supplement in making your investment decision. You should read this prospectus supplement, as well as the documents incorporated by reference herein, the additional information described under the section titled "Where You Can Find More Information" and "Incorporation of Certain Documents by Reference" in this prospectus supplement and any free writing prospectus that we have authorized for use in connection with this offering, before investing in our common stock.

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference in this prospectus supplement were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

We use various trademarks and trade names in our business, including without limitation our corporate name and logo. All other trademarks or trade names referred to in this prospectus supplement are the property of their respective owners. Solely for convenience, the trademarks and trade names in this prospectus supplement may be referred to without the ® and ™ symbols, but such references should not be construed as any indicator that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto. This prospectus supplement and the documents incorporated by reference herein also contain estimates, projections and other information concerning our industry, our business, and the markets for certain diseases, including data regarding the estimated size of those markets, and the incidence and prevalence of certain medical conditions. Information that is based on estimates, forecasts, projections, market research or similar methodologies is inherently subject to uncertainties and actual events or circumstances may differ materially from events and

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circumstances reflected in this information. Unless otherwise expressly stated, we obtained this industry, business, market and other data from reports, research surveys, studies and similar data prepared by market research firms and other third parties, industry, medical and general publications, government data and similar sources.

We are offering to sell, and seeking offers to buy, shares of our common stock only in jurisdictions where such offers and sales are permitted. The distribution of this prospectus supplement and the offering of our common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement must inform themselves about, and observe any restrictions relating to, the offering of our common stock and the distribution of this prospectus supplement outside the United States. This prospectus supplement does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

As used in this prospectus supplement, unless the context otherwise requires, references to the "company," "we," "us" and "our" refer to Rubius Therapeutics, Inc. and, where appropriate, our subsidiary.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights selected information about us and this offering and does not contain all of the information that you should consider before investing in our securities. Before investing in our common stock, you should carefully read the information contained and incorporated by reference in this prospectus supplement, including the sections titled "Risk Factors" and the financial statements and accompanying notes.

Company Overview

We have generated hundreds of RCTs using our RED PLATFORM®, a highly versatile and proprietary cellular therapy platform. We are utilizing our universal engineering and manufacturing processes to advance a broad pipeline of RCT product candidates into clinical trials in rare diseases, cancer and autoimmune diseases. Common design and manufacturing elements of our RCTs should enable us to achieve significant advantages in product development. We are establishing end to end manufacturing capabilities and plan to develop commercial infrastructure to further establish ourselves as a leading, fully integrated cellular therapy company.

Company Information

We were incorporated under the laws of the State of Delaware in April 2013 under the previous name, VL26, Inc. In January 2015, we changed our name to Rubius Therapeutics, Inc. Our principal executive offices are located at 399 Binney Street, Suite 300 Cambridge, MA 02139, and our telephone number is (617) 679-9600. Our website address is www.rubiustx.com. We do not incorporate the information on or accessible through our website into this prospectus supplement, and you should not consider any information on, or that can be accessed through, our website as part of this prospectus supplement. You should not rely on any such information in making your decision whether to purchase our common stock. Our common stock trades on The Nasdaq Global Select Market under the symbol "RUBY".

On July 20, 2018, we completed our initial public offering, or IPO, pursuant to which we issued and sold 12,055,450 shares of common stock, inclusive of 1,572,450 shares pursuant to the full exercise of the underwriters' option to purchase additional shares. We received proceeds of $254.3 million after deducting underwriting discounts and commissions and other offering costs.

Implications of Being an Emerging Growth Company

As a company with less than $1.07 billion in revenue during our most recently completed fiscal year, we qualify as an "emerging growth company" as defined in Section 2(a) of the Securities Act of 1933, as amended, or the Securities Act, as modified by the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. As an emerging growth company, we may take advantage of specified reduced disclosure and other requirements that are otherwise applicable, in general, to public companies that are not emerging growth companies. These provisions include:

•: reduced disclosure about our executive compensation arrangements;
•: exemption from the non-binding stockholder advisory votes on executive compensation or golden parachute arrangements; and

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•: exemption from the auditor attestation requirement in the assessment of our internal control over financial reporting.

We may take advantage of these exemptions for up to five years following the completion of our IPO or such earlier time that we are no longer an emerging growth company. We would cease to be an emerging growth company if we have more than $1.07 billion in annual revenues as of the end of a fiscal year; we are deemed to be a "large accelerated filer," under the rules of the SEC, which means the market value of our equity securities that is held by non-affiliates exceeds $700 million as of the prior June 30 ^th ; or if we issue more than $1.0 billion of non-convertible debt over a three-year-period. We may choose to take advantage of some, but not all, of the available exemptions.

In addition, the JOBS Act provides that an emerging growth company can take advantage of an extended transition period for complying with new or revised accounting standards. This provision allows an emerging growth company to delay the adoption of some accounting standards until those standards would otherwise apply to private companies. We have elected not to "opt out" of such extended transition period, which means that when a standard is issued or revised and it has different application dates for public or private companies, we will adopt the new or revised standard at the time private companies adopt the new or revised standard and will do so until such time that we either (i) irrevocably elect to "opt out" of such extended transition period or (ii) no longer qualify as an emerging growth company. While we have not made such an irrevocable election, we have not delayed the adoption of any applicable accounting standards.

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THE OFFERING


Common stock offered by us:		Shares of our common stock having an aggregate offering price of up to $100,000,000.
Common stock to be outstanding immediately after this offering:		Up to 86,708,204 shares (as more fully described in the notes following this table), assuming sales of 6,854,009 shares of our common stock in this offering at an offering price of $14.59 per share, which was the last reported sale price of our common stock on The Nasdaq Global Select Market on July 29, 2019. The actual number of shares issued will vary depending on how many shares of our common stock we choose to sell and the prices at which such sales occur.
Manner of offering:		"At the market offering" that may be made from time to time on The Nasdaq Global Select Market or other existing trading market for our common stock through our sales agents, J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC. See "Plan of Distribution" on page S-22 of this prospectus supplement.
Use of proceeds:		Our management will retain broad discretion regarding the allocation and use of the net proceeds. We intend to use the net proceeds from this offering primarily to fund activities relating to the advancement of our product candidates, and for other general corporate purposes, including, but not limited to, research and development costs, including the conduct of one or more clinical trials, preclinical studies and process development and manufacturing of our product candidates, potential strategic acquisitions of complementary businesses, services or technologies, expansion of our technology infrastructure and capabilities, working capital and capital expenditures. See "Use of Proceeds" on page S-15 of this prospectus supplement.
Risk factors:		Investing in our common stock involves significant risks. See "Risk Factors" on page S-7 of this prospectus supplement and under similar headings in the documents incorporated by reference into this prospectus supplement for a discussion of the factors you should carefully consider before deciding to invest in our common stock.
The Nasdaq Global Select Market symbol:		"RUBY"

All information in this prospectus supplement related to the number of shares of our common stock to be outstanding immediately after this offering is based on 79,854,195 shares of our common stock outstanding as of March 31, 2019. The number of shares outstanding as of March 31, 2019 as used throughout this prospectus supplement, unless otherwise indicated, excludes:

•: 15,469,088 shares of common stock issuable upon the exercise of stock options outstanding as of March 31, 2019 at a weighted-average exercise price of $9.65 per share;

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•: 3,513,602 shares of common stock reserved for future issuance as of March 31, 2019 under our 2018 Stock Option and Incentive Plan; and
•: 1,743,836 shares of common stock reserved for the future issuance as of March 31, 2019 under our 2018 Employee Stock Purchase Plan.

Unless otherwise stated, all information contained in this prospectus supplement assumes no exercise of stock options after March 31, 2019 and reflects an assumed public offering price of $14.59, which was the last reported sale price of our common stock on The Nasdaq Global Select Market on July 29, 2019.

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RISK FACTORS

Investing in our common stock involves a high degree of risk. Before making an investment decision, you should carefully consider the risks described below and in our most recent Annual Report on Form 10-K and any subsequent Quarterly Reports on Form 10-Q or Current Reports on Form 8-K , as well as any amendments thereto reflected in subsequent filings with the SEC, each of which are incorporated by reference in this prospectus supplement, and all of the other information in this prospectus supplement, including our financial statements and related notes incorporated by reference herein. If any of these risks is realized, our business, financial condition, results of operations and prospects could be materially and adversely affected. In that event, the trading price of our common stock could decline and you could lose part or all of your investment. Additional risks and uncertainties that are not yet identified or that we currently believe to be immaterial may also materially harm our business, financial condition, results of operations and prospects and could result in a complete loss of your investment.

Risks Related To This Offering and Our Common Stock

The price of our common stock historically has been volatile, which may affect the price at which you could sell any shares of our common stock.

The market price for our common stock historically has been highly volatile and could continue to be subject to wide fluctuations in response to various factors. The market price for our common stock has varied between a high price of $26.90 on August 23, 2018 and a low price of $12.71 on January 18, 2019 in the twelve-month period ending on July 29, 2019. This volatility may affect the price at which you could sell the shares of our common stock, and the sale of substantial amounts of our common stock could adversely affect the price of our common stock. Our stock price is likely to continue to be volatile and subject to significant price and volume fluctuations in response to market and other factors, including:

•: the commencement, enrollment or results of our ongoing and planned clinical trials of our product candidates or any future clinical trials we may conduct, or changes in the development status of our product candidates;
•: any delay in our regulatory filings for our product candidates and any adverse development or perceived adverse development with respect to the applicable regulatory authority's review of such filings;
•: adverse results from or delays in clinical trials of our product candidates;
•: our decision to initiate a clinical trial, not to initiate a clinical trial or to terminate an existing clinical trial;
•: adverse regulatory decisions, including failure to receive regulatory approval of our product candidates;
•: changes in laws or regulations applicable to our products, including but not limited to clinical trial requirements for approvals;
•: adverse developments concerning our manufacturers;
•: our inability to obtain adequate product supply for any approved product or inability to do so at acceptable prices;
•: our inability to establish collaborations, if needed;
•: our failure to commercialize our product candidates;
•: additions or departures of key scientific or management personnel;

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•: unanticipated serious safety concerns related to the use of our product candidates;
•: introduction of new products or services by our competitors;
•: announcements of significant acquisitions, strategic partnerships, joint ventures or capital commitments by us or our competitors;
•: our ability to effectively manage our growth;
•: the size and growth of our initial target markets;
•: actual or anticipated variations in quarterly operating results;
•: our cash position;
•: our failure to meet the estimates and projections of the investment community or that we may otherwise provide to the public;
•: publication of research reports about us or our industry, or cellular therapies in particular, or positive or negative recommendations or withdrawal of research coverage by securities analysts;
•: changes in the market valuations of similar companies;
•: overall performance of the equity markets;
•: sales of our common stock by us or our stockholders in the future;
•: trading volume of our common stock;
•: adoption of new accounting standards;
•: ineffectiveness of our internal controls;
•: disputes or other developments relating to proprietary rights, including patents, litigation matters and our ability to obtain patent protection for our technologies;
•: significant lawsuits, including patent or stockholder litigation;
•: general political and economic conditions; and
•: other events or factors, many of which are beyond our control.

In addition, the stock market in general, and the market for biopharmaceutical companies in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of these companies. Broad market and industry factors may negatively affect the market price of our common stock, regardless of our actual operating performance. If the market price of our common stock does not exceed their purchase price, our stockholders may not realize any return on their investment in us and may lose some or all of their investment. In the past, securities class action litigation has often been instituted against companies following periods of volatility in the market price of a company's securities. This type of litigation, if instituted, could result in substantial costs and a diversion of management's attention and resources, which would harm our business, operating results or financial condition.

We have broad discretion in the use of the net proceeds from this offering and may invest or spend the proceeds in ways with which you do not agree and in ways that may not yield a return on your investment.

Our management will have broad discretion in the application of the net proceeds from this offering, including for any of the purposes described in the section titled "Use of Proceeds," as well as our existing cash, and you will be relying on the judgment of our management regarding such application. You will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used effectively. Our management might not apply the net proceeds or our

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existing cash in ways that ultimately increase the value of your investment. If we do not invest or apply the net proceeds from this offering or our existing cash in ways that enhance stockholder value, we may fail to achieve expected results, which could cause our stock price to decline. Pending their use, we may invest the net proceeds from this offering in short-term U.S. Treasury securities with insignificant rates of return. These investments may not yield a favorable return to our stockholders.

If you purchase our common stock in this offering, you will incur immediate and substantial dilution in the net tangible book value of your shares.

The offering price per share in this offering may exceed the net tangible book value per share of our common stock outstanding prior at the time of sale. Assuming that an aggregate of 6,854,009 shares of our common stock are sold at a price of $14.59 per share, the last reported sale price of our common stock on The Nasdaq Global Select Market on July 29, 2019, for aggregate gross proceeds of $100 million, after deducting commissions and estimated offering expenses payable by us, investors in this offering would experience immediate dilution of $9.19 per share, representing the difference between our as adjusted net tangible book value per share as of March 31, 2019, after giving effect to this offering, and the assumed offering price.

This dilution is due to the substantially lower price paid by some of our investors who purchased shares prior to this offering as compared to the price offered to the public in this offering and the exercise of stock options granted to our employees, directors and consultants. In addition, we have a significant number of stock options outstanding. The exercise of any of these outstanding options would result in further dilution. As a result of the dilution to investors purchasing shares in this offering, investors may receive significantly less than the purchase price paid in this offering, if anything, in the event of our liquidation. Further, because we expect we will need to raise additional capital to fund our future activities, we may in the future sell substantial amounts of common stock or securities convertible into or exchangeable for common stock.

Future issuances of common stock or common stock-related securities, together with the exercise of outstanding stock options, if any, may result in further dilution. For a further description of the dilution that you will experience immediately after this offering, see the section titled "Dilution."

Future sales and issuances of our common stock or rights to purchase common stock, including pursuant to our equity incentive plans, could result in additional dilution of the percentage ownership of our stockholders and could cause our stock price to fall.

Additional capital will be needed in the future to continue our planned operations. To the extent we raise additional capital by issuing equity securities, our stockholders may experience substantial dilution. We may sell common stock, convertible securities or other equity securities in one or more transactions at prices and in a manner we determine from time to time. If we sell common stock, convertible securities or other equity securities in more than one transaction, investors may be materially diluted by subsequent sales. These sales may also result in material dilution to our existing stockholders, and new investors could gain rights superior to our existing stockholders.

In addition, sales of a substantial number of shares of our outstanding common stock in the public market could occur at any time. These sales, or the perception in the market that the holders of a large number of shares of common stock intend to sell shares, could reduce the market price of our common stock. Persons who were our stockholders prior to our initial public offering continue to hold a substantial number of shares of our common stock that many of them are now able to sell in the public market. Significant portions of these shares are held by a relatively small number of stockholders. Sales by our stockholders of a substantial number of shares, or the expectation that such sales may occur, could significantly reduce the market price of our common stock.

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The actual number of shares we will issue under the Distribution Agreement, at any one time or in total, is uncertain.

Subject to certain limitations in the Distribution Agreement and compliance with applicable law, we have the discretion to deliver a transaction proposal to any Sales Agent at any time throughout the term of the Distribution Agreement. The number of shares that are sold by any such Sales Agent after delivering a transaction proposal will fluctuate based on the market price of our common stock during the sales period and limits we set with such Sales Agent. Because the price per share of each share sold will fluctuate based on the market price of our common stock during the sales period, it is not possible at this stage to predict the number of shares that will be ultimately issued.

The common stock offered hereby will be sold in "at the market offerings," and investors who buy shares at different times will likely pay different prices.

Investors who purchase shares in this offering at different times will likely pay different prices, and so may experience different outcomes in their investment results. We will have discretion, subject to market demand, to vary the timing, prices, and numbers of shares sold, and there is no minimum or maximum sales price. Investors may experience a decline in the value of their shares as a result of share sales made at prices lower than the prices they paid.

Our principal stockholders and management own a significant percentage of our stock and will be able to exert significant control over matters subject to stockholder approval.

As of June 30, 2019, our executive officers, directors, five percent or greater stockholders and their affiliates beneficially own approximately 71.4% of our outstanding voting stock. These stockholders will have the ability to influence us through their ownership positions. These stockholders may be able to determine all matters requiring stockholder approval. For example, these stockholders, acting together, may be able to control elections of directors or approval of any merger, sale of assets, or other major corporate transaction. This may prevent or discourage unsolicited acquisition proposals or offers for our common stock that you may believe are in your best interest as one of our stockholders.

Sales of a substantial number of shares of our common stock in the public market could cause our stock price to fall.

Sales of a substantial number of shares of our common stock in the public market or the perception that these sales might occur could depress the market price of our common stock and could impair our ability to raise capital through the sale of additional equity securities. We are unable to predict the effect that such sales may have on the prevailing market price of our common stock. In addition, the sale of substantial amounts of our common stock could adversely impact its price. As of March 31, 2019, we had outstanding 79,854,195 shares of our common stock and options to purchase 15,469,088 shares of our common stock (of which 2,721,985 were exercisable as of that date). The sale or the availability for sale of a large number of shares of our common stock in the public market could cause the price of our common stock to decline.

If securities or industry analysts do not publish research, or publish inaccurate or unfavorable research, about our business, our stock price and trading volume could decline.

The trading market for our common stock will depend, in part, on the research and reports that securities or industry analysts publish about us or our business. Securities and industry analysts may not publish an adequate amount of research on us, which may negatively impact the trading price for our stock. In addition, if one or more of the analysts who cover us downgrade our stock or publish inaccurate or unfavorable research about our business, our stock price would likely decline. Further, if our operating results fail to meet the forecasts of analysts, our stock price would likely decline. If one

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or more of these analysts cease coverage of us or fail to publish reports on us regularly, demand for our stock could decrease, which might cause our stock price and trading volume to decline.

Because we do not anticipate paying any cash dividends on our capital stock in the foreseeable future, capital appreciation, if any, will be your sole source of gain.

We have never declared or paid cash dividends on our capital stock. We currently intend to retain all of our future earnings, if any, to finance the growth and development of our business. In addition, the terms of any future debt agreements may preclude us from paying dividends. As a result, capital appreciation, if any, of our common stock will be your sole source of gain for the foreseeable future.

We could be subject to securities class action litigation.

In the past, securities class action litigation has often been brought against a company following a decline in the market price of its securities. This risk is especially relevant for us because biotechnology and pharmaceutical companies have experienced significant stock price volatility in recent years. If we face such litigation, it could result in substantial costs and a diversion of management's attention and resources, which could harm our business.

Changes in tax law may adversely affect us or our investors.

The rules dealing with U.S. federal, state and local income taxation are constantly under review by persons involved in the legislative process and by the U.S. Internal Revenue Service, or IRS, and the U.S. Treasury Department. Changes to tax laws (which changes may have retroactive application) could adversely affect us or holders of our common stock. In recent years, many such changes have been made and changes are likely to continue to occur in the future. For example, the Tax Cuts and Jobs Act, or the TCJA, was enacted in 2017 and significantly reformed the U.S. Internal Revenue Code of 1986, as amended, or the Code. The TCJA, among other things, contains significant changes to corporate taxation, including reduction of the corporate tax rate from a top marginal rate of 35% to a flat rate of 21%, limitation of the tax deduction for net interest expense to 30% of adjusted earnings (except for certain small businesses), limitation of the deduction for net operating losses to 80% of current year taxable income and elimination of net operating loss carrybacks, in each case, for losses generated after December 31, 2017 (though any such net operating losses may be carried forward indefinitely), and modifying or repealing many business deductions and credits (including reducing the business tax credit for certain clinical testing expenses incurred in the testing of certain drugs for rare diseases or conditions generally referred to as "orphan drugs"). It cannot be predicted whether, when, in what form, or with what effective dates, tax laws, regulations and rulings may be enacted, promulgated or issued, which could result in an increase in our or our shareholders' tax liability or require changes in the manner in which we operate in order to minimize or mitigate any adverse effects of changes in tax law.

We are an "emerging growth company," and the reduced disclosure requirements applicable to emerging growth companies may make our common stock less attractive to investors.

We are an "emerging growth company," as defined in the JOBS Act. For so long as we remain an emerging growth company, we are permitted and intend to rely on exemptions from certain disclosure requirements that are applicable to other public companies that are not emerging growth companies. These exemptions include not being required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act of 2002, not being required to comply with any requirement that may be adopted by the Public Company Accounting Oversight Board regarding mandatory audit firm rotation or a supplement to the auditor's report providing additional information about the audit and the financial statements, reduced disclosure obligations regarding executive compensation and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation

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and shareholder approval of any golden parachute payments not previously approved. We cannot predict whether investors will find our common stock less attractive if we rely on these exemptions. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock and our stock price may be reduced or more volatile.

Under the JOBS Act, emerging growth companies can also delay adopting new or revised accounting standards until such time as those standards apply to private companies. We have elected not to "opt out" of such extended transition period, which means that when a standard is issued or revised and it has different application dates for public or private companies, we will adopt the new or revised standard at the time private companies adopt the new or revised standard and will do so until such time that we either (i) irrevocably elect to "opt out" of such extended transition period or (ii) no longer qualify as an emerging growth company. This may make comparison of our financial statements with the financial statements of another public company that is not an emerging growth company, or an emerging growth company that has opted out of using the extended transition period, difficult or impossible because of the potential differences in accounting standards used.

Our ability to use net operating losses and research and development credits to offset future taxable income may be subject to certain limitations .

As of December 31, 2018, we had U.S. federal and state net operating loss, or NOL, carryforwards of $93.2 million and $93.9 million, respectively, which may be available to offset future taxable income. The federal NOLs include $37.2 million which expire at various dates through 2037 and $56.0 million which carryforward indefinitely. The state NOLs expire at various dates through 2038. As of December 31, 2018, we also had U.S. federal and state research and development tax credit, or credits, carryforwards of $3.0 million and $1.1 million, respectively, which may be available to offset future tax liabilities and begin to expire in 2034 and 2031, respectively. In addition, in general, under Sections 382 and 383 of the Code and corresponding provisions of state law, a corporation that undergoes an "ownership change" is subject to limitations on its ability to utilize its pre-change NOLs or credits to offset future taxable income or taxes. For these purposes, an ownership change generally occurs where the aggregate stock ownership of one or more stockholders or groups of stockholders who owns at least 5% of a corporation's stock increases its ownership by more than 50 percentage points over its lowest ownership percentage within a specified testing period. Our existing NOLs or credits may be subject to limitations arising from previous ownership changes, including in connection with our recent private placements, IPO and other transactions. In addition, future changes in our stock ownership, including this offering, many of which are outside of our control, could result in ownership changes under Sections 382 and 383 of the Code and our ability to utilize NOLs or credits may be impaired. Our NOLs or credits may also be impaired under state law. Accordingly, we may not be able to utilize a material portion of our NOLs or credits. Furthermore, our ability to utilize our NOLs or credits is conditioned upon our attaining profitability and generating U. S. federal and state taxable income. We have incurred significant net losses since our inception and anticipate that we will continue to incur significant losses for the foreseeable future; and therefore, we do not know whether or when we will generate the U.S. federal or state taxable income necessary to utilize our NOLs or credits that are subject to limitation by Sections 382 and 383 of the Code. Additionally, under the TCJA, NOLs generated after December 31, 2017 can only offset 80% of current year taxable income.

The market price of our common stock may be adversely affected by market conditions affecting the stock markets in general, including price and trading fluctuations on The Nasdaq Global Select Market.

Market conditions may result in volatility in the level of, and fluctuations in, market prices of stocks generally and, in turn, our common stock and sales of substantial amounts of our common stock in the market, in each case being unrelated or disproportionate to changes in our operating performance. Concerns over global stability and economic conditions in the U.S. and abroad have contributed to the extreme volatility of the markets, which may have an effect on the market price of our common stock.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement and the information and documents incorporated by reference herein, contain forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act. Any statements about our expectations, beliefs, plans, objectives, assumptions or future events or performance are not historical facts and may be forward-looking. These statements are often, but are not always, made through the use of words or phrases such as "may," "will," "could," "should," "expects," "intends," "plans," "anticipates," "believes," "estimates," "predicts," "projects," "potential," "continue," and similar expressions, or the negative of these terms, or similar expressions. Accordingly, these statements involve estimates, assumptions, risks and uncertainties which could cause actual results to differ materially from those expressed in them. Any forward-looking statements are qualified in their entirety by reference to the factors discussed throughout this prospectus supplement and the documents incorporated by reference herein, and in particular those factors referenced in the section "Risk Factors."

This prospectus supplement, any related free writing prospectus and the information and documents incorporated by reference herein contain forward-looking statements that are based on our management's belief and assumptions and on information currently available to our management. These statements relate to future events or our future financial performance, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed or implied by these forward-looking statements. Forward-looking statements include, but are not limited to, statements about:

•: the success, cost and timing of our product development activities and clinical trials, including statements regarding the timing of initiation and completion of studies or trials and related preparatory work, the period during which the results of the trials will become available, and our research and development programs;
•: our ability to advance any product candidate into or successfully complete any clinical trial;
•: our ability or the potential to successfully manufacture our product candidates for clinical trials or for commercial use, if approved;
•: our plans to renovate, customize and operate our manufacturing facility purchased in 2018;
•: the potential for our identified research priorities to advance our technologies;
•: our ability to maintain regulatory approval, if obtained, of any of our current or future product candidates, and any related restrictions, limitations and/or warnings in the label of an approved product candidate;
•: the ability to license additional intellectual property relating to our product candidates and to comply with our existing license agreements;
•: our ability to commercialize our products in light of the intellectual property rights of others;
•: developments relating to cellular therapies, including red blood cell therapies;
•: the success of competing therapies that are or become available;
•: our ability to obtain funding for our operations, including funding necessary to complete further development and commercialization of our product candidates;
•: the commercialization of our product candidates, if approved;
•: our plans to research, develop and commercialize our product candidates;
•: our ability to attract collaborators with development, regulatory and commercialization expertise;

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•: future agreements with third parties in connection with the commercialization of our product candidates and any other approved product;
•: the size and growth potential of the markets for our product candidates, and our ability to serve those markets;
•: the rate and degree of market acceptance of our product candidates;
•: regulatory developments in the United States and foreign countries;
•: our ability to contract with third-party suppliers and manufacturers and their ability to perform adequately;
•: our ability to attract and retain key scientific or management personnel;
•: the accuracy of our estimates regarding expenses, future revenue, capital requirements and needs for additional financing;
•: the impact of laws and regulations;
•: our expectations regarding our ability to obtain and maintain intellectual property protection for our product candidates;
•: our expectations regarding the period during which we qualify as an "emerging growth company" under the Jumpstart Our Business Startups Act; and
•: our use of the proceeds from the initial public offering and this offering.

These forward-looking statements are neither promises nor guarantees of future performance due to a variety of risks and uncertainties, many of which are beyond our control, which could cause actual results to differ materially from those indicated by these forward-looking statements, including, without limitation the risk factors and cautionary statements described in other documents that we file from time to time with the SEC, specifically under "Item 1A: Risk Factors" and elsewhere in our most recent Annual Report on Form 10-K and any subsequent Quarterly Reports on Form 10-Q or Current Reports on Form 8-K, and the section of the prospectus titled "Risk Factors."

The forward-looking statements in this prospectus supplement, any related free writing prospectus and the documents incorporated by reference represent our views as of their respective dates. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we assume no obligation to update or revise any forward-looking statements except to the extent required by applicable law. You should, therefore, not rely on these forward-looking statements as representing our views as of any date subsequent to the dates on which they were made.

This prospectus supplement, any related free writing prospectus and the documents incorporated by reference also contain estimates, projections and other information concerning our industry, our business, and the markets for certain diseases, including data regarding the estimated size of those markets, and the incidence and prevalence of certain medical conditions. Information that is based on estimates, forecasts, projections, market research or similar methodologies is inherently subject to uncertainties and actual events or circumstances may differ materially from events and circumstances reflected in this information. Unless otherwise expressly stated, we obtained this industry, business, market and other data from reports, research surveys, studies and similar data prepared by market research firms and other third parties, industry, medical and general publications, government data and similar sources.

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USE OF PROCEEDS

We may issue and sell shares of our common stock having aggregate sales proceeds of up to $100,000,000 from time to time. The amount of proceeds from this offering will depend upon the number of shares of our common stock sold and the market price at which they are sold. There can be no assurance that we will be able to sell any shares under or fully utilize the Distribution Agreement with the Sales Agents as a source of financing. Therefore, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time.

We intend to use any net proceeds from this offering primarily to fund activities relating to the advancement of our product candidates, and for other general corporate purposes. General corporate purposes may include research and development costs, including the conduct of one or more clinical trials and/or preclinical studies and process development and manufacturing of our product candidates, potential strategic acquisitions of complementary businesses, services or technologies, expansion of our technology infrastructure and capabilities, working capital and capital expenditures. We may temporarily invest the net proceeds in a variety of capital preservation instruments, including investment grade, interest bearing instruments and U.S. government securities, until they are used for their stated purpose. We have not determined the amount of net proceeds to be used specifically for such purposes. As a result, management will retain broad discretion over the allocation of net proceeds.

DIVIDEND POLICY

We have never declared or paid cash dividends on our capital stock. We intend to retain all of our future earnings, if any, to finance the growth and development of our business. We do not intend to pay cash dividends to our stockholders in the foreseeable future.

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DILUTION

If you invest in our common stock in this offering, your ownership interest will be diluted to the extent of the difference between the public offering price per share of our common stock in this offering and the as adjusted net tangible book value per share of our common stock immediately after this offering. Our net tangible book value as of March 31, 2019 was approximately $371.6 million, or approximately $4.65 per share of common stock. Net tangible book value per share represents the amount of total tangible assets (total assets less intangible assets) less total liabilities, divided by the number of shares of our common stock outstanding as of March 31, 2019.

Dilution in net tangible book value per share to new investors participating in this offering represents the difference between the amount per share paid by purchasers in this offering and the as adjusted net tangible book value per share of our common stock immediately after giving effect to this offering. After giving effect to the assumed sale of 6,854,009 shares of our common stock in the aggregate amount of approximately $100,000,000 at an assumed offering price of $14.59 per share, the last reported sale price of our common stock on July 29, 2019, and after deducting commissions and estimated offering expenses payable by us, our as adjusted net tangible book value as of March 31, 2019 would have been approximately $468.2 million, or approximately $5.40 per share of common stock. This represents an immediate increase in net tangible book value of $0.75 per share of common stock to our existing stockholders and immediate dilution in net tangible book value of $9.19 per share of common stock to investors participating in this offering at the assumed offering price.

Dilution per share to new investors is determined by subtracting as adjusted net tangible book value per share after this offering from the assumed public offering price per share paid by new investors. The following table illustrates this per share dilution:


Assumed offering price per share			$	14.59
Historical net tangible book value per share as of March 31, 2019	$	4.65
Increase in net tangible book value per share attributable to new investors participating in this offering		0.75

As adjusted net tangible book value per share as of March 31, 2019, after giving effect to this offering				5.40

Dilution per share to new investors participating in this offering			$	9.19

The table above assumes for illustrative purposes that an aggregate of 6,854,009 shares of our common stock are sold at a price of $14.59 per share, the last reported sale price of our common stock on The Nasdaq Global Select Market on July 29, 2019, for aggregate gross proceeds of approximately $100,000,000. The shares sold in this offering, if any, will be sold from time to time at various prices. An increase of $1.00 per share in the price at which the shares are sold from the assumed offering price of $14.59 per share shown in the table above, assuming all of our common stock in the aggregate amount of approximately $100,000,000 is sold at that price, would result in an increase to our as adjusted net tangible book value per share after the offering to $5.43 and an increase in dilution per share to new investors participating in this offering to $10.16, after deducting commissions and estimated offering expenses payable by us. A decrease of $1.00 per share in the price at which the shares are sold from the assumed offering price of $14.59 per share shown in the table above, assuming all of our common stock in the aggregate amount of approximately $100,000,000 is sold at that price, would result in a decrease to our as adjusted net tangible book value per share after the offering to $5.37 and a decrease in dilution per share to new investors participating in this offering to $8.22, after deducting commissions and estimated offering expenses payable by us. This information is supplied for illustrative purposes only, and will adjust based on the actual offering prices, the actual number of shares that we offer and sell in this offering and other terms of each sale of shares in this offering.

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The information above and in the foregoing table is based upon 79,854,195 shares of our common stock outstanding as of March 31, 2019. The information above and in the foregoing table excludes:

•: 15,469,088 shares of common stock issuable upon the exercise of stock options outstanding as of March 31, 2019 at a weighted-average exercise price of $9.65 per share;
•: 3,513,602 shares of common stock reserved for future issuance as of March 31, 2019 under our 2018 Stock Option and Incentive Plan; and
•: 1,743,836 shares of common stock reserved for the future issuance as of March 31, 2019 under our 2018 Employee Stock Purchase Plan.

In addition, we may choose to raise additional capital in the future through the sale of equity or convertible debt securities due to market conditions or strategic considerations, even if we believe we have sufficient funds for our current or future operating plans. To the extent that any of our outstanding options are exercised, new options are issued under our equity incentive plans or we issue additional shares of common stock or other equity or convertible debt securities in the future, there will be further dilution to investors participating in this offering.

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MATERIAL U.S. FEDERAL INCOME TAX CONSIDERATIONS FOR NON-U.S. HOLDERS

The following discussion is a summary of certain material U.S. federal income tax considerations for non-U.S. holders (as defined below) with respect to their ownership and disposition of shares of our common stock issued pursuant to this offering. For purposes of this discussion, a non-U.S. holder means a beneficial owner of our common stock that is for U.S. federal income tax purposes:

•: a non-resident alien individual;
•: a foreign corporation or any other foreign organization taxable as a corporation for U.S. federal income tax purposes; or
•: a foreign estate or trust, the income of which is not subject to U.S. federal income tax on a net income basis.

This discussion does not address the tax treatment of partnerships or other entities that are pass-through entities for U.S. federal income tax purposes or persons that hold their common stock through partnerships or other pass-through entities. A partner in a partnership or other pass-through entity that will hold our common stock should consult his, her or its tax advisor regarding the tax consequences of acquiring, holding and disposing of our common stock through a partnership or other pass-through entity, as applicable.

This discussion is based on current provisions of the U.S. Internal Revenue Code of 1986, as amended, which we refer to as the Code, existing and proposed U.S. Treasury Regulations promulgated thereunder, current administrative rulings and judicial decisions, all as in effect as of the date of this prospectus supplement and all of which are subject to change or to differing interpretation, possibly with retroactive effect. Any such change or differing interpretation could alter the tax consequences to non-U.S. holders described in this prospectus supplement. There can be no assurance that the U.S. Internal Revenue Service, which we refer to as the IRS, will not challenge one or more of the tax consequences described herein. We assume in this discussion that a non-U.S. holder holds shares of our common stock as a capital asset within the meaning of Section 1221 of the Code, generally property held for investment.

This discussion does not address all aspects of U.S. federal income taxation that may be relevant to a particular non-U.S. holder in light of that non-U.S. holder's individual circumstances nor does it address U.S. state, local or non-U.S. taxes, the alternative minimum tax, the rules regarding qualified small business stock within the meaning of Section 1202 of the Code, the Medicare tax on net investment income or any other aspect of any U.S. federal tax other than the income tax. This discussion also does not consider any specific facts or circumstances that may apply to a non-U.S. holder and does not address the special tax rules applicable to particular non-U.S. holders, such as:

•: insurance companies;
•: tax-exempt or governmental organizations;
•: financial institutions;
•: brokers or dealers in securities;
•: regulated investment companies;
•: pension plans;
•: "controlled foreign corporations," "passive foreign investment companies," and corporations that accumulate earnings to avoid U.S. federal income tax;
•: "qualified foreign pension funds" as defined in Section 897(I)(2) of the Code and entities all of the interests of which are held by qualified foreign pension funds;

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•: persons that have a functional currency other than the U.S. dollar;
•: persons deemed to sell our common stock under the constructive sale provisions of the Code;
•: persons that hold our common stock as part of a straddle, hedge, conversion transaction, synthetic security or other integrated investment;
•: persons who hold or receive our common stock pursuant to the exercise of any employee stock option or otherwise as compensation; and
•: certain U.S. expatriates.

This discussion is for general information only and is not tax advice. Accordingly, all prospective non-U.S. holders of our common stock should consult their tax advisors with respect to the U.S. federal, state, local and non-U.S. tax consequences of the purchase, ownership and disposition of our common stock.

Distributions on Our Common Stock

As described in the "Dividend Policy" section above, we do not anticipate paying any cash dividends to our stockholders in the foreseeable future. Distributions, if any, on our common stock will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. If a distribution exceeds our current and accumulated earnings and profits, the excess will be treated as a tax-free return of the non-U.S. holder's investment, up to such holder's tax basis in the common stock. Any remaining excess will be treated as capital gain, subject to the tax treatment described below in "Gain on Sale or Other Taxable Disposition of Our Common Stock." Any such distributions will also be subject to the discussions below under the sections titled "Backup Withholding and Information Reporting" and "FATCA."

Subject to the discussion in the following two paragraphs in this section, dividends paid to a non-U.S. holder generally will be subject to withholding of U.S. federal income tax at a 30% rate or such lower rate as may be specified by an applicable income tax treaty between the United States and such holder's country of residence. Dividends that are treated as effectively connected with a trade or business conducted by a non-U.S. holder within the United States and, if an applicable income tax treaty so provides, that are attributable to a permanent establishment or a fixed base maintained by the non-U.S. holder within the United States, are generally exempt from the 30% withholding tax if the non-U.S. holder satisfies applicable certification and disclosure requirements. However, such U.S. effectively connected income, net of specified deductions and credits, is taxed at the same graduated U.S. federal income tax rates applicable to United States persons (as defined in the Code). Any U.S. effectively connected income received by a non-U.S. holder that is a corporation may also, under certain circumstances, be subject to an additional "branch profits tax" at a 30% rate or such lower rate as may be specified by an applicable income tax treaty between the United States and such holder's country of residence.

A non-U.S. holder of our common stock who claims the benefit of an applicable income tax treaty between the United States and such holder's country of residence generally will be required to provide a properly executed IRS Form W-8BEN or W-8BEN-E (or successor form) to the applicable withholding agent and satisfy applicable certification and other requirements. Non-U.S. holders are urged to consult their tax advisors regarding their entitlement to benefits under a relevant income tax treaty. A non-U.S. holder that is eligible for a reduced rate of U.S. withholding tax under an income tax treaty may obtain a refund or credit of any excess amounts withheld by timely filing a U.S. tax return with the IRS.

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Gain on Sale or Other Taxable Disposition of Our Common Stock

Subject to the discussions below under "Backup Withholding and Information Reporting" and "FATCA," a non-U.S. holder generally will not be subject to any U.S. federal income or withholding tax on any gain realized upon such holder's sale or other taxable disposition of shares of our common stock unless:

•: the gain is effectively connected with the non-U.S. holder's conduct of a U.S. trade or business and, if an applicable income tax treaty so provides, is attributable to a permanent establishment or a fixed base maintained by such non-U.S. holder in the United States, in which case the non-U.S. holder generally will be taxed on a net income basis at the graduated U.S. federal income tax rates applicable to United States persons (as defined in the Code) and, if the non-U.S. holder is a foreign corporation, the branch profits tax described above in "Distributions on Our Common Stock" also may apply;
•: the non-U.S. holder is a nonresident alien individual who is present in the United States for 183 days or more in the taxable year of the disposition and certain other conditions are met, in which case the non-U.S. holder will be subject to a 30% tax (or such lower rate as may be specified by an applicable income tax treaty between the United States and such holder's country of residence) on the net gain derived from the disposition, which may be offset by certain U.S. source capital losses of the non-U.S. holder, if any (even though the individual is not considered a resident of the United States), provided that the non-U.S. holder has timely filed U.S. federal income tax returns with respect to such losses; or
•: we are, or have been, at any time during the five-year period preceding such sale or other taxable disposition (or the non-U.S. holder's holding period, if shorter) a U.S. real property holding corporation, unless our common stock is regularly traded on an established securities market and the non-U.S. holder holds no more than 5% of our outstanding common stock, directly or indirectly, actually or constructively, during the shorter of the 5-year period ending on the date of the disposition or the period that the non-U.S. holder held our common stock. Generally, a corporation is a U.S. real property holding corporation only if the fair market value of its U.S. real property interests equals or exceeds 50% of the sum of the fair market value of its worldwide real property interests plus its other assets used or held for use in a trade or business. Although there can be no assurance, we do not believe that we are, or have been, a U.S. real property holding corporation, or that we are likely to become one in the future. No assurance can be provided that our common stock will be regularly traded on an established securities market for purposes of the rules described above.

Backup Withholding and Information Reporting

We must report annually to the IRS and to each non-U.S. holder the gross amount of the distributions on our common stock paid to such holder and the tax withheld, if any, with respect to such distributions. Non-U.S. holders may have to comply with specific certification procedures to establish that the holder is not a United States person (as defined in the Code) in order to avoid backup withholding at the applicable rate with respect to dividends on our common stock. Dividends paid to non-U.S. holders subject to withholding of U.S. federal income tax, as described above in "Distributions on Our Common Stock," generally will be exempt from U.S. backup withholding.

Information reporting and backup withholding will generally apply to the proceeds of a disposition of our common stock by a non-U.S. holder effected by or through the U.S. office of any broker, U.S. or foreign, unless the holder certifies its status as a non-U.S. holder and satisfies certain other requirements, or otherwise establishes an exemption. Generally, information reporting and backup withholding will not apply to a payment of disposition proceeds to a non-U.S. holder where the transaction is effected outside the United States through a non-U.S. office of a broker. However, for

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information reporting purposes, dispositions effected through a non-U.S. office of a broker with substantial U.S. ownership or operations generally will be treated in a manner similar to dispositions effected through a U.S. office of a broker.

Non-U.S. holders should consult their tax advisors regarding the application of the information reporting and backup withholding rules to them. Copies of information returns may be made available to the tax authorities of the country in which the non-U.S. holder resides or is incorporated under the provisions of a specific treaty or agreement. Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a non-U.S. holder can be refunded or credited against the non-U.S. holder's U.S. federal income tax liability, if any, provided that an appropriate claim is filed with the IRS in a timely manner.

FATCA

Provisions of the Code commonly referred to as the Foreign Account Tax Compliance Act, or FATCA, generally impose a U.S. federal withholding tax at a rate of 30% on payments of dividends on our common stock paid to a foreign entity unless (i) if the foreign entity is a "foreign financial institution," such foreign entity undertakes certain due diligence, reporting, withholding, and certification obligations, (ii) if the foreign entity is not a "foreign financial institution," such foreign entity identifies certain of its U.S. investors, if any, or (iii) the foreign entity is otherwise exempt under FATCA. Such withholding may also apply to gross proceeds from the sale or other disposition of our common stock, although under recently proposed U.S. Treasury Regulations, no withholding would apply to such gross proceeds. The preamble to the proposed regulations specifies that taxpayers (including withholding agents) are permitted to rely on the proposed regulations pending finalization. Under certain circumstances, a non-U.S. holder may be eligible for refunds or credits of this withholding tax. An intergovernmental agreement between the United States and an applicable foreign country may modify the requirements described in this paragraph. Non-U.S. holders should consult their tax advisors regarding the possible implications of this legislation on their investment in our common stock and the entities through which they hold our common stock, including, without limitation, the process and deadlines for meeting the applicable requirements to prevent the imposition of the 30% withholding tax under FATCA.

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PLAN OF DISTRIBUTION

We have entered into a Distribution Agreement, which we refer to as the "Distribution Agreement," with J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC, which we refer to collectively as the "Sales Agents," and each individually as a "Sales Agent", under which we may offer and sell shares of our common stock having an aggregate gross sales price of up to $100 million from time to time through any of the Sales Agents. Sales of the shares of common stock, if any, may be made in transactions that are deemed to be "at the market offerings," as defined in Rule 415(a)(4) promulgated under the Securities Act, including sales made by means of ordinary brokers' transactions on The Nasdaq Global Select Market or into any other existing trading market for our common stock at market prices and such other sales as agreed upon by us and a Sales Agent. The Distribution Agreement has been filed as an exhibit to our registration statement on Form S-3 of which this prospectus supplement forms a part.

When requested by us, an applicable Sales Agent will offer the shares of common stock subject to the terms and conditions of the Distribution Agreement, which may be on a daily basis for periods of time, or as we may otherwise agree with such applicable Sales Agents. We will designate the maximum number of shares of common stock to be sold through such applicable Sales Agent when we request it to do so. Each Sales Agent has agreed, subject to the terms and conditions of the Distribution Agreement, to use its commercially reasonable efforts to execute our orders to sell, as our agent and on our behalf, shares of our common stock submitted to the applicable Sales Agent from time to time by us, consistent with its normal sales and trading practices. We may instruct the Sales Agents not to place shares of common stock at or below a price designated by us. In any event, the shares of common stock shall be placed by the Sales Agents substantially at market price. We or the Sales Agents may suspend the offering of shares of common stock under the Distribution Agreement upon proper notice to the other party.

We will pay the Sales Agents a commission of 3.0% of the gross proceeds of any shares sold pursuant to this prospectus supplement, and reimburse the Sales Agents for up to an aggregate of $60,000 of their expenses, including fees and disbursements to their legal counsel, in connection with the execution of the Distribution Agreement. The estimated offering expenses payable by us, in addition to such commission and expenses, are approximately $400,000, which includes legal, accounting and printing costs and various other fees associated with registering the shares of common stock. The remaining sale proceeds, after deducting any other transaction fees, will equal our net proceeds from the sale of such shares.

The applicable Sales Agent will provide written confirmation to us before the open on the Nasdaq Global Select Market on the day following each day on which shares of common stock are sold under the Distribution Agreement. Each confirmation will include the number of shares sold on that day, the aggregate gross proceeds of such sales and the net proceeds to us. Settlement for sales of shares of common stock will occur, unless otherwise agreed, on the second business day following the date on which such sales were made.

Under the terms of the Distribution Agreement, we also may sell our common stock to a Sales Agent as principal for its own account, at a price agreed upon at the time of sale. If we sell shares to a Sales Agent as principal, we will enter into a separate terms agreement with such Sales Agent, and we will describe such agreement in a separate prospectus supplement or pricing supplement.

We will report in a prospectus supplement and/or our filings with the SEC under the Exchange Act at least quarterly the number of shares of our common stock sold through the Sales Agents under the Distribution Agreement, the net proceeds to us and the compensation paid by us to the Sales Agents in connection with the sales of our common stock.

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In connection with the sale of our common stock on our behalf, the Sales Agents will be deemed to be "underwriters" within the meaning of the Securities Act and the compensation of the Sales Agents will be deemed to be underwriting commissions or discounts. We have agreed to indemnify the Sales Agents against certain liabilities, including liabilities under the Securities Act. We have also agreed to contribute to payments the Sales Agents may be required to make in respect of such liabilities.

Each Sales Agent and its respective affiliates have engaged in, and may in the future engage in, investment banking and other commercial dealings in the ordinary course of business with us or our affiliates. They have received, or may in the future receive, customary fees and commissions for these transactions.

In addition, in the ordinary course of their business activities, the Sales Agents and their respective affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers. Such investments and securities activities may involve securities and/or instruments of ours or our affiliates. The Sales Agents and their respective affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or financial instruments and may hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

If either any Sales Agent or we have reason to believe that the exemptive provisions set forth in Rule 101(c)(1) of Regulation M under the Exchange Act are not satisfied, that party will promptly notify the other and sales of our common stock under the Distribution Agreement will be suspended until that or other exemptive provisions have been satisfied in the judgment of such Sales Agent and us.

The offering of our common stock pursuant to the Distribution Agreement will terminate upon the earlier of (i) the sale of all shares of our common stock subject to the Distribution Agreement, (ii) the termination of the Distribution Agreement by us and/or by the Sales Agents and (iii) the third anniversary of the effective date of the registration statement of which this prospectus forms a part.

This prospectus supplement in electronic format may be made available on a website maintained by the Sales Agents, and the Sales Agents may distribute this prospectus supplement electronically.

LEGAL MATTERS

Certain legal matters in connection with this offering and the validity of the securities offered by this prospectus supplement will be passed upon for us by Goodwin Procter LLP, Boston, MA. J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC are being represented in connection with this offering by Latham & Watkins LLP.

EXPERTS

The financial statements incorporated in this prospectus supplement by reference to the Annual Report on Form 10-K for the year ended December 31, 2018 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

WHERE YOU CAN FIND MORE INFORMATION

This prospectus supplement is part of a registration statement on Form S-3 that we have filed with the SEC. This prospectus supplement, filed as part of the registration statement, does not contain all the information set forth in the registration statement and its exhibits and schedules, portions of which have been omitted as permitted by the rules and regulations of the SEC. For further information about

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us, we refer you to the registration statement and to its exhibits and schedules. Certain information in the registration statement has been omitted from this prospectus supplement in accordance with the rules of the SEC.

We are subject to the reporting and information requirements of the Exchange Act and, in accordance therewith, file annual, quarterly and special reports, proxy statements and other information with the SEC. These documents also may be accessed through the SEC's electronic data gathering, analysis and retrieval system, or EDGAR, via electronic means, including the SEC's home page on the Internet ( www.sec.gov ). Written requests for such copies should be directed to Investor Relations Department, Rubius Therapeutics, Inc., 399 Binney Street, Suite 300, Cambridge, Massachusetts 02139, and our website is located at www.rubiustx.com.

We have the authority to designate and issue more than one class or series of stock having various preferences, conversion and other rights, voting powers, restrictions, limitations as to dividends, qualifications, and terms and conditions of redemption. See "Description of Capital Stock" in the accompanying base prospectus. We will furnish a full statement of the relative rights and preferences of each class or series of our stock which has been so designated and any restrictions on the ownership or transfer of our stock to any shareholder upon request and without charge. Information contained on our website is not incorporated by reference into this prospectus supplement and, therefore, is not part of this prospectus supplement or any accompanying prospectus supplement.

INCORPORATION BY REFERENCE

The SEC allows us to incorporate by reference the information and reports we file with it, which means that we can disclose important information to you by referring you to these documents. The information incorporated by reference is an important part of this prospectus supplement, and information that we file later with the SEC will automatically update and supersede the information already incorporated by reference. We are incorporating by reference the documents listed below, which we have already filed with the SEC, and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, including all filings made after the date of this prospectus supplement, except as to any portion of any future report or document that is not deemed filed under such provisions, until we sell all of the securities:

•: our Annual Report on Form 10-K for the year ended December 31, 2018, filed with the SEC on March 28, 2019;
•: our Annual Report on Form 10-K/A (Amendment No. 1) for the year ended December 31, 2018, filed with the SEC on May 15, 2019;
•: the information specifically incorporated by reference into our Annual Report on Form 10-K for the year ended December 31, 2018 from our definitive proxy statement on Schedule 14A (other than information furnished rather than filed), which was filed with the SEC on April 12, 2019;
•: our Quarterly Report on Form 10-Q for the quarter ended March 31, 2019, filed with the SEC on May 15, 2019;
•: our Current Reports on Form 8-K filed with the SEC on January 22, 2019 , March 11, 2019 , March 25, 2019 , May 15, 2019 and May 23, 2019 (in each case, except for information contained therein which is furnished rather than filed); and
•: the description of our common stock contained in our registration statement on Form 8-A filed with the SEC on July 13, 2018, including any amendments or reports filed for the purposes of updating this description.

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We incorporate by reference any future filings made with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act between the date of this prospectus supplement and the termination of the offering.

Notwithstanding the foregoing, unless specifically stated to the contrary, information that we furnish (and that is not deemed "filed" with the SEC) under Items 2.02 and 7.01 of any Current Report on Form 8-K, including the related exhibits under Item 9.01, is not incorporated by reference into this prospectus supplement or the registration statement of which this prospectus supplement is a part.

Any statement contained in a document that is incorporated by reference will be modified or superseded for all purposes to the extent that a statement contained in this prospectus supplement, or in any other document that is subsequently filed with the SEC and incorporated by reference into this prospectus supplement, modifies or is contrary to that previous statement. Any statement so modified or superseded will not be deemed a part of this prospectus supplement, except as so modified or superseded. Since information that we later file with the SEC will update and supersede previously incorporated information, you should look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus supplement or in any documents previously incorporated by reference have been modified or superseded.

Upon request, we will provide, without charge, to each person, including any beneficial owner, to whom a copy of this prospectus is delivered, a copy of the documents incorporated by reference into this prospectus supplement but not delivered therewith. You may request a copy of these filings, and any exhibits we have specifically incorporated by reference as an exhibit in this prospectus supplement, at no cost by writing or telephoning us at the following address: Investor Relations Department, Rubius Therapeutics, Inc., 399 Binney Street, Suite 300, Cambridge, Massachusetts 02139, (617) 679-9600.

You may also access these documents, free of charge on the SEC's website at www.sec.gov or on our website at www. rubiustx.com . Information contained on our website is not incorporated by reference into this prospectus supplement and you should not consider any information on, or that can be accessed from, our website as part of this prospectus supplement.

This prospectus supplement is part of a registration statement we filed with the SEC. We have incorporated exhibits into this registration statement. You should read the exhibits carefully for provisions that may be important to you.

You should rely only on the information incorporated by reference or provided in this prospectus supplement. We have not authorized anyone to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information in this prospectus supplement or in the documents incorporated by reference is accurate as of any date other than the date on the front of this prospectus supplement or those documents.

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Up to $100,000,000

Common Stock

PROSPECTUS SUPPLEMENT


J.P. Morgan		Jefferies		SVB Leerink

, 2019

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Part II-INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution

The expenses payable by Rubius Therapeutics, Inc. (the "Registrant" or the "Company") in connection with the issuance and distribution of the securities being registered (other than underwriting discounts and commissions, if any) are set forth below. Each item listed is estimated, except for the Securities and Exchange Commission (the "SEC") registration fee.


SEC registration fee	$	54,540
FINRA filing fee		68,000
Legal fees and expenses			*
Accounting fees and expenses			*
Printing fees and expenses			*
Transfer agent and trustee fees			*
Miscellaneous			*

Total	$		*

*: Estimated expenses not presently known

Item 15. Indemnification of Directors and Officers

Section 145 of the Delaware General Corporation Law, or the DGCL, authorizes a corporation to indemnify its directors and officers against liabilities arising out of actions, suits and proceedings to which they are made or threatened to be made a party by reason of the fact that they have served or are currently serving as a director or officer to a corporation. The indemnity may cover expenses (including attorneys' fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the director or officer in connection with any such action, suit or proceeding. Section 145 permits corporations to pay expenses (including attorneys' fees) incurred by directors and officers in advance of the final disposition of such action, suit or proceeding. In addition, Section 145 provides that a corporation has the power to purchase and maintain insurance on behalf of its directors and officers against any liability asserted against them and incurred by them in their capacity as a director or officer, or arising out of their status as such, whether or not the corporation would have the power to indemnify the director or officer against such liability under Section 145.

We have adopted provisions in our certificate of incorporation and by-laws that limit or eliminate the personal liability of our directors to the fullest extent permitted by the DGCL, as it now exists or may in the future be amended. Consequently, a director will not be personally liable to us or our stockholders for monetary damages or breach of fiduciary duty as a director, except for liability for:

•: any breach of the director's duty of loyalty to us or our stockholders;
•: any act or omission not in good faith or that involves intentional misconduct or a knowing violation of law;
•: any unlawful payments related to dividends or unlawful stock purchases, redemptions or other distributions; or
•: any transaction from which the director derived an improper personal benefit.

These limitations of liability do not alter director liability under the federal securities laws and do not affect the availability of equitable remedies such as an injunction or rescission.

In addition, our by-laws provide that:

•: we will indemnify our directors, officers and, in the discretion of our board of directors, certain employees to the fullest extent permitted by the DGCL, as it now exists or may in the future be amended; and

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•: we will advance reasonable expenses, including attorneys' fees, to our directors and, in the discretion of our board of directors, to our officers and certain employees, in connection with legal proceedings relating to their service for or on behalf of us, subject to limited exceptions.

We have entered into indemnification agreements with each of our directors and with certain of our executive officers. These agreements provide that we will indemnify each of our directors, certain of our executive officers and, at times, their affiliates to the fullest extent permitted by Delaware law. We will advance expenses, including attorneys' fees (but excluding judgments, fines and settlement amounts), to each indemnified director, executive officer or affiliate in connection with any proceeding in which indemnification is available and we will indemnify our directors and officers for any action or proceeding arising out of that person's services as a director or officer brought on behalf of the Company and/or in furtherance of our rights. Additionally, each of our directors may have certain rights to indemnification, advancement of expenses and/or insurance provided by their affiliates, which indemnification relates to and might apply to the same proceedings arising out of such director's services as a director referenced herein. Nonetheless, we have agreed in the indemnification agreements that the Company's obligations to those same directors are primary and any obligation of the affiliates of those directors to advance expenses or to provide indemnification for the expenses or liabilities incurred by those directors are secondary.

We also maintain general liability insurance which covers certain liabilities of our directors and officers arising out of claims based on acts or omissions in their capacities as directors or officers, including liabilities under the Securities Act.

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Item 16. Exhibits

EXHIBIT INDEX

		Description


1.1	*	Form of Underwriting Agreement

1.2		Distribution Agreement dated August 1, 2019 by and among the Registrant and J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC

3.1		Amended and Restated Certificate of Incorporation of the Registrant (Incorporated by reference to Exhibit 3.1 to the Registrant's Form 8-K (File No. 001-38586) filed with the SEC on July 23, 2018)

3.2		Amended and Restated By-laws of the Registrant (Incorporated by reference to Exhibit 3.2 to the Registrant's Form 8-K (File No. 001-38586) filed with the SEC on July 23, 2018)

4.1		Specimen Common Stock Certificate (Incorporated by reference to Exhibit 4.1 to the Registrant's Registration Statement on Form S-1, as amended (File No. 333-225840) filed on July 2, 2018)

4.2		Second Amended and Restated Investors' Rights Agreement among the Registrant and certain of its stockholders, dated February 23, 2018 (Incorporated by reference to Exhibit 4.2 to the Registrant's Registration Statement on Form S-1 (File No. 333-225840) filed on June 22, 2018)

4.3		Form of Senior Indenture between the Registrant and one or more trustees to be named

4.4		Form of Subordinated Indenture between the Registrant and one or more trustees to be named

4.5	*	Form of Certificate of Designations

4.6	*	Form of Warrant Agreement

4.7	*	Form of Unit Agreement and Unit Certificate

4.8	*	Form of Preferred Stock Certificate

5.1		Opinion of Goodwin Procter LLP

5.2		Opinion of Goodwin Procter LLP relating to the distribution agreement prospectus supplement

23.1		Consent of PricewaterhouseCoopers LLP, independent registered public accounting firm

23.2		Consent of Goodwin Procter LLP (included in Exhibit 5.1)

23.3		Consent of Goodwin Procter LLP (included in Exhibit 5.2)

24.1		Power of Attorney (included on the signature page to this registration statement)

25.1	**	Form T-1 Statement of Eligibility of Trustee for Senior Indenture under the Trust Indenture Act of 1939

25.2	**	Form T-1 Statement of Eligibility of Trustee for Subordinated Indenture under the Trust Indenture Act of 1939

*: To be filed, if necessary, by amendment or as an exhibit to a document to be incorporated or deemed to be incorporated by reference in this registration statement, including a Current Report on Form 8-K.
**: To be filed by amendment pursuant to Section 305(b)(2) of the Trust Indenture Act of 1939.

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Item 17. Undertakings

The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Securities and Exchange Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement; and

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement; provided, however , that paragraphs (l)(i), (l)(ii) and (l)(iii) of this section do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Securities and Exchange Commission by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement;

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof;

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering;

(4) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(i) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(ii) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(l)(i), (vii), or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof; provided, however , that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the

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registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date;

(5) That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser;

(6) That, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof;

(7) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue;

(8) That, for purposes of determining any liability under the Securities Act of 1933, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the registrant pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act of 1933 shall be deemed to be part of this registration statement as of the time it was declared effective;

(9) That, for the purpose of determining any liability under the Securities Act of 1933, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof; and

(10) To file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of Section 310 of the Trust Indenture Act of 1939 in accordance with the rules and regulations prescribed by the Securities and Exchange Commission under Section 305(b)(2) of the Trust Indenture Act of 1939.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Cambridge, Commonwealth of Massachusetts, on this 1st day of August, 2019.


		RUBIUS THERAPEUTICS, INC.
		By:		/s/ Pablo J. Cagnoni Pablo J. Cagnoni Chief Executive Officer

KNOW ALL BY THESE PRESENTS, that each person whose signature appears below hereby severally constitutes and appoints each of Pablo J. Cagnoni and Andrew Oh, and each of them singly, as such person's true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for such person and in such person's name, place and stead, in any and all capacities, to sign any or all amendments (including, without limitation, post-effective amendments) to this registration statement (or any registration statement for the same offering that is to be effective upon filing pursuant to Rule 462(b) under the Securities Act of 1933), and to file the same, with all exhibits thereto, and all documents in connection therewith, with the Securities and Exchange Commission, granting unto each said attorney-in-fact and agent full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as such person might or could do in person, hereby ratifying and confirming all that any said attorney-in-fact and agent, or any substitute or substitutes of any of them, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

Signature	Title	Date


/s/ Pablo J. Cagnoni Pablo J. Cagnoni, M.D.	Chief Executive Officer and Director (Principal Executive Officer)	August 1, 2019
/s/ David R. Epstein David R. Epstein	Chairman, Director	August 1, 2019
/s/ Andrew M. Oh Andrew M. Oh	Chief Financial Officer (Principal Financial Officer and Principal Accounting Officer)	August 1, 2019
/s/ Noubar B. Afeyan Noubar B. Afeyan, Ph.D.	Director	August 1, 2019
/s/ Francis Cuss Francis Cuss, M.B., B.Chir, FRCP	Director	August 1, 2019

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Signature	Title	Date


/s/ Natalie Holles Natalie Holles	Director	August 1, 2019
/s/ Robert S. Langer Robert S. Langer, Sc.D.	Director	August 1, 2019
/s/ Michael Rosenblatt Michael Rosenblatt, M.D.	Director	August 1, 2019
/s/ Catherine A. Sohn Catherine A. Sohn, Pharm.D.	Director	August 1, 2019
/s/ Jonathan R. Symonds Jonathan R. Symonds, CBE	Director	August 1, 2019

Exhibit 1.2

DISTRIBUTION AGREEMENT

August 1, 2019

J.P. Morgan Securities LLC
383 Madison Avenue

New York, New York 10179

Jefferies LLC
520 Madison Avenue
New York, New York 10022

SVB Leerink LLC
One Federal Street, 37th Floor
Boston, Massachusetts 02110

Ladies and Gentlemen:

Rubius Therapeutics, Inc., a Delaware corporation (the “ Company ”), confirms its agreement with each of J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC, as agent and/or principal under any Terms Agreement (as defined in Section 1(a) below) (each an “ Agent ” and collectively, the “ Agents ”), with respect to the issuance and sale from time to time by the Company, in the manner and subject to the terms and conditions described below in this Distribution Agreement (this “ Agreement ”), of Common Stock, $0.001 par value per share (the “ Common Stock ”), of the Company having an aggregate Gross Sales Price (as defined in Section 2(b) below) of up to $100,000,000 (the “ Maximum Amount ”) on the terms set forth in Section 1 of this Agreement. Such shares are hereinafter collectively referred to as the “ Shares ” and are described in the Prospectus referred to below.

The Company has filed or will file with the Securities and Exchange Commission (the “ Commission ”) a registration statement on Form S-3 (the “ registration statement ”) for the registration of the Shares and other securities of the Company under the Securities Act of 1933, as amended, and the rules and regulations of the Commission thereunder (collectively, the “ Act ”); and such registration statement sets forth the terms of the offering, sale and plan of distribution of the Shares and contains additional information concerning the Company and its business. Except where the context otherwise requires, “ Registration Statement ,” as used herein, means the registration statement, as amended at the time of such registration statement’s effectiveness for purposes of Section 11 of the Act, as such section applies to the Agents, including (1) all documents filed as a part thereof or incorporated or deemed to be incorporated by reference therein and (2) any information contained or incorporated by reference in a prospectus filed with the Commission pursuant to Rule 424(b) under the Act, to the extent such information is deemed, pursuant to Rule 430B or Rule 430C under the Act, to be part of the registration statement at the effective time. “ Basic Prospectus ” means the prospectus filed as part of the Registration Statement, including the documents incorporated by reference therein as of the date of such prospectus; “ Prospectus Supplement ” means the prospectus supplement relating to the Shares filed as part of the Registration Statement or, if applicable, the most recent prospectus supplement relating to the Shares, to be filed by the Company with the Commission

pursuant to Rule 424(b) under the Act, in each case, on or before the second business day after the date of its first use in connection with a public offering or sale of Shares pursuant hereto (or such earlier time as may be required under the Act), in the form furnished by the Company to the Agents in connection with the offering of the Shares; “ Prospectus ” means the Prospectus Supplement (and any additional prospectus supplement prepared in accordance with the provision of Section 4(h) of this Agreement and filed in accordance with the provisions of Rule 424(b)) together with the Basic Prospectus attached to or used with the Prospectus Supplement; and “ Permitted Free Writing Prospectus ” has the meaning set forth in Section 3(b). Any reference herein to the Registration Statement, the Basic Prospectus, the Prospectus Supplement, the Prospectus or any Permitted Free Writing Prospectus shall, unless otherwise stated, be deemed to refer to and include the documents, if any, incorporated by reference, or deemed to be incorporated by reference, therein (the “ Incorporated Documents ”), including, unless the context otherwise requires, the documents, if any, filed as exhibits to such Incorporated Documents. Any reference herein to the terms “amend,” “amendment” or “supplement” with respect to the Registration Statement, the Basic Prospectus, the Prospectus Supplement, the Prospectus or any Permitted Free Writing Prospectus shall, unless stated otherwise, be deemed to refer to and include the filing of any document under the Securities Exchange Act of 1934, as amended, and the rules and regulations thereunder (collectively, the “ Exchange Act ”) on or after the initial effective date of the Registration Statement, or the date of the Basic Prospectus, the Prospectus Supplement, the Prospectus or such Permitted Free Writing Prospectus, as the case may be, and deemed to be incorporated therein by reference. References in this Agreement to financial statements or other information that is “contained,” “included,” “described,” “set forth” or “provided” in the Registration Statement, the Basic Prospectus, the Prospectus Supplement, the Prospectus or any Permitted Free Writing Prospectus and any similar references shall, unless stated otherwise, include any information incorporated or deemed to be incorporated by reference therein.

The Company and each Agent agree as follows:

1. Issuance and Sale .

(a) Upon the basis of the representations, warranties and agreements and subject to the terms and conditions set forth herein and provided the Company provides the applicable Agent with any due diligence materials and information reasonably requested by such Agent necessary for such Agent to satisfy its due diligence obligations, on any Exchange Business Day (as defined below) selected by the Company, the Company and such Agent shall enter into an agreement in accordance with Section 2 hereof regarding the number of Shares to be placed by such Agent (or any affiliate or successor of such Agent), as agent, and the manner in which and other terms upon which such placement is to occur (each such transaction being referred to as an “ Agency Transaction ”). The Company may also offer to sell the Shares directly to any Agent (or any affiliate or successor of any Agent), as principal, in which event such parties shall enter into a separate agreement (each, a “ Terms Agreement ”) in substantially the form of Exhibit A hereto (with such changes thereto as may be agreed upon by the Company and such Agent to accommodate a transaction involving additional underwriters), relating to such sale in accordance with Section 2(g) of this Agreement (each such transaction being referred to as a “ Principal Transaction ”). As used herein, (i) the “ Term ” shall be the period commencing on the date hereof and ending on the earlier of (x) the date on which the aggregate Gross Sales Price

of Shares issued and sold pursuant to this Agreement and any Terms Agreements is equal to the Maximum Amount and (y) any termination of this Agreement pursuant to Section 8, (ii) an “ Exchange Business Day ” means any day during the Term that is a trading day for the Exchange other than a day on which trading on the Exchange is scheduled to close prior to its regular weekday closing time, and (iii) “ Exchange ” means the Nasdaq Global Select Market.

(b) Subject to the terms and conditions set forth below, the Company appoints each Agent as agent in connection with the offer and sale of Shares in any Agency Transactions entered into hereunder. Each Agent (or any affiliate or successor of such Agent) will use commercially reasonable efforts, consistent with its normal trading and sales practices, to sell such Shares in accordance with the terms and subject to the conditions hereof and of the applicable Transaction Acceptance (as defined below). Neither the Company nor any Agent shall have any obligation to enter into an Agency Transaction. The Company shall be obligated to issue and sell through the Agents, and each Agent shall be obligated to use commercially reasonable efforts, consistent with its normal trading and sales practices and as provided herein and in the applicable Transaction Acceptance, to place Shares only if and when the Company makes a Transaction Proposal to such Agent related to such an Agency Transaction and a Transaction Acceptance related to such Agency Transaction has been delivered to the Company by such Agent as provided in Section 2 below.

(c) Each Agent, as agent in any Agency Transaction, hereby covenants and agrees not to make any sales of the Shares on behalf of the Company pursuant to this Agreement other than (A) by means of ordinary brokers’ transactions between members of the Exchange that qualify for delivery of a Prospectus in accordance with Rule 153 under the Act and meet the definition of an “at the market offering” under Rule 415(a)(4) under the Act (such transactions are hereinafter referred to as “ At the Market Offerings ”) and (B) such other sales of the Shares on behalf of the Company in its capacity as agent of the Company as shall be agreed by the Company and such Agent in writing.

(d) If Shares are to be sold in an Agency Transaction in an At the Market Offering, the applicable Agent will confirm in writing to the Company and the other Agents the number of Shares sold on any Exchange Business Day and the related Gross Sales Price and Net Sales Price (as each of such terms is defined in Section 2(b) below) no later than the opening of trading on the immediately following Exchange Business Day.

(e) If the Company shall default on its obligation to deliver Shares to an Agent pursuant to the terms of any Agency Transaction or Terms Agreement, the Company shall (i) indemnify and hold harmless such Agent and its successors and assigns from and against any and all losses, claims, damages, liabilities and expenses arising from or as a result of such default by the Company and (ii) notwithstanding any such default, pay to such Agent the commission to which it would otherwise be entitled in connection with such sale in accordance with Section 2(b) below.

(f) The Company acknowledges and agrees that (i) there can be no assurance that any Agent will be successful in selling the Shares, (ii) no Agent shall incur any liability or obligation to the Company or any other person or entity if it does not sell Shares for any reason other than a failure by such Agent to use its commercially reasonable efforts consistent with its normal

trading and sales practices and applicable law and regulations to sell such Shares in accordance with the terms of this Agreement, and (iii) no Agent shall be under any obligation to purchase Shares on a principal basis pursuant to this Agreement, except as may otherwise be specifically agreed by such Agent and the Company in a Terms Agreement.

2. Transaction Acceptances and Terms Agreements .

(a) The Company may, from time to time during the Term, propose to an Agent that they enter into an Agency Transaction to be executed on a specified Exchange Business Day or over a specified period of Exchange Business Days, which proposal shall be made to such Agent by telephone or by email or by any other form acceptable to such Agent from any of the individuals listed as an authorized representative of the Company on Schedule A hereto to make such sales and shall set forth the information specified below (each, a “ Transaction Proposal ”). If such Agent agrees to the terms of such proposed Agency Transaction or if the Company and such Agent mutually agree to modified terms for such proposed Agency Transaction, then such Agent shall promptly deliver to the Company by email a notice (each, a “ Transaction Acceptance ”) confirming the terms of such proposed Agency Transaction as set forth in such Transaction Proposal or setting forth the modified terms for such proposed Agency Transaction as agreed by the Company and such Agent, as the case may be, whereupon such Agency Transaction shall become a binding agreement between the Company and such Agent. Each Transaction Proposal shall specify:

(i) the Exchange Business Day(s) on which the Shares subject to such Agency Transaction are intended to be sold (each, a “ Purchase Date ”);

(ii) the maximum number of Shares to be sold by such Agent (the “ Specified Number of Shares ”) on, or over the course of, such Purchase Date(s), or as otherwise agreed between the Company and such Agent and documented in the relevant Transaction Acceptance; and

(iii) the lowest price per Share, if any, at which the Company is willing to sell Shares on each such Purchase Date or a formula pursuant to which such lowest price shall be determined (each, a “ Floor Price ”).

A Transaction Proposal shall not set forth a Specified Number of Shares and Floor Price the product of which, when added to the aggregate Gross Sales Price of Shares previously purchased and to be purchased pursuant to pending Transaction Acceptances (if any) hereunder and any Terms Agreements, results or could result in an aggregate Gross Sales Price that exceeds the Maximum Amount, nor shall it set forth a Floor Price which is lower than the minimum price authorized from time to time by the Company’s board of directors or, if permitted by applicable law and the Company’s charter and by-laws, a duly authorized committee thereof. The Company shall have responsibility for maintaining records with respect to the aggregate number and aggregate Gross Sales Price of

Shares sold and for otherwise monitoring the availability of Shares for sale under the Registration Statement and for ensuring that the aggregate number and aggregate Gross Sales Price of Shares offered and sold does not exceed, and the price at which any Shares are offered or sold is not lower than, the aggregate number and aggregate Gross Sales Price of Shares and the minimum price authorized from time to time by the Company’s board of directors or, if permitted by applicable law and the Company’s charter and by-laws, a duly authorized committee thereof. In the event that more than one Transaction Acceptance with respect to any Purchase Date(s) is delivered by the applicable Agent to the Company, the latest Transaction Acceptance shall govern any sales of Shares for the relevant Purchase Date(s), except to the extent of any action occurring pursuant to a prior Transaction Acceptance and prior to the delivery to the Company of the latest Transaction Acceptance. The Company or the applicable Agent may, upon notice to the other such party by either email (with receipt confirmed by telephone) or telephone (confirmed promptly by e-mail), suspend or terminate the offering of the Shares pursuant to Agency Transactions for any reason; provided , however , that such suspension or termination shall not affect or impair the parties’ respective obligations with respect to the Shares sold hereunder prior to the giving of such notice or their respective obligations under any Terms Agreement. Notwithstanding the foregoing, if the terms of any Agency Transaction contemplate that Shares shall be sold on more than one Purchase Date, then the Company and the applicable Agent shall mutually agree to such additional terms and conditions as they deem reasonably necessary in respect of such multiple Purchase Dates, and such additional terms and conditions shall be set forth in or confirmed by, as the case may be, the relevant Transaction Acceptance and be binding to the same extent as any other terms contained therein.

(b) The Purchase Date(s) in respect of the Shares deliverable pursuant to any Transaction Acceptance shall be set forth in or confirmed by, as the case may be, the applicable Transaction Acceptance. Such Agent’s commission for any Shares sold through such Agent pursuant to this Agreement shall be 3.0% of the actual sales price of such Shares (the “ Gross Sales Price ”), which commission shall be confirmed by the applicable Transaction Acceptance; provided , however , that such commission shall not apply when an Agent acts as principal, in which case such commission or a discount shall be set forth in the applicable Terms Agreement. Notwithstanding the foregoing, in the event the Company engages an Agent for a sale of Shares in an Agency Transaction that would constitute a “distribution,” within the meaning of Rule 100 of Regulation M under the Exchange Act or a “block” within the meaning of Rule 10b-18(a)(5) under the Exchange Act, the Company will provide such Agent, at such Agent’s request and upon reasonable advance notice to the Company, on or prior to the Settlement Date the opinions of counsel, accountants’ letters and officers’ certificates pursuant to Section 6 hereof, each dated the Settlement Date, and such other documents and information as such Agent shall reasonably request, and the Company and such Agent will agree to compensation that is customary for such Agent with respect to such transaction. The Gross Sales Price less the applicable Agent’s commission and after deduction for any transaction fees, transfer taxes or similar taxes or fees imposed by any governmental,

regulatory or self-regulatory organization in respect of the sale of the applicable Shares is referred to herein at the “ Net Sales Price .”

(c) Payment of the Net Sales Price for Shares sold by the Company on any Purchase Date pursuant to a Transaction Acceptance shall be made by the applicable Agent to the Company by wire transfer of immediately available funds to the account of the Company (which the Company shall provide to the applicable Agent at least one Exchange Business Day prior to the applicable Agency Settlement Date (as defined below)) against delivery of such Shares to the applicable Agent’s account, or an account of the applicable Agent’s designee, at The Depository Trust Company through its Deposit and Withdrawal at Custodian System (“ DWAC ”) or by such other means of delivery as may be agreed to by the Company and such Agent. Such payment and delivery shall be made at or about 10:00 a.m. (New York City time) on the second Exchange Business Day (or such other day as may, from time to time, become standard industry practice for settlement of such a securities issuance or as agreed to by the Company and such Agent) following each Purchase Date (each, an “ Agency Settlement Date ”).

(d) If, as set forth in or confirmed by, as the case may be, the related Transaction Acceptance, a Floor Price has been agreed to by the parties with respect to a Purchase Date, and the applicable Agent thereafter determines and notifies the Company that the sales price per Share for such Agency Transaction would not be at least equal to such Floor Price, then the Company shall not be obligated to issue and sell through such Agent, and such Agent shall not be obligated to place, the Shares proposed to be sold pursuant to such Agency Transaction on such Purchase Date, unless the Company and such Agent otherwise agree in writing.

(e) If either the Company or an Agent has reason to believe that the exemptive provisions set forth in Rule 101(c)(1) of Regulation M under the Exchange Act are not satisfied with respect to the Shares, it shall promptly notify the other party and sales of the Shares under this Agreement, any Transaction Acceptance or any Terms Agreement shall be suspended until that or other exemptive provisions have been satisfied in the judgment of the Company and such Agent. On or prior to the delivery of a prospectus that is required (whether physically or through compliance with Rule 172 under the Act or any similar rule) in connection with the offering or sale of the Shares, the Company shall calculate the average daily trading volume (as defined under “ ADTV ” by Rule 100 of Regulation M under the Exchange Act) of the Common Stock based on market data provided by Bloomberg L.P. or such other sources as agreed upon by the Company and the Agent.

(f) (i) If the Company wishes to issue and sell the Shares pursuant to this Agreement but other than as set forth in Section 2(a) of this Agreement, it will notify the applicable Agent of the proposed terms of the Principal Transaction. If an Agent, acting as principal, wishes to accept such proposed terms (which it may decline to do for any reason in its sole discretion) or, following discussions with the Company, wishes to accept amended terms, the Company and such Agent shall enter into a Terms Agreement setting forth the terms of such Principal Transaction.

(ii) The terms set forth in a Terms Agreement shall not be binding on the Company or the applicable Agent unless and until the Company and such Agent

have each executed and delivered such Terms Agreement accepting all of the terms of such Terms Agreement. In the event of a conflict between the terms of this Agreement and the terms of a Terms Agreement, the terms of such Terms Agreement shall control.

(g) Each sale of the Shares to an Agent in a Principal Transaction shall be made in accordance with the terms of this Agreement and a Terms Agreement, which shall provide for the sale of such Shares to, and the purchase thereof by, such Agent. A Terms Agreement may also specify certain provisions relating to the reoffering of such Shares by such Agent. The commitment of an Agent to purchase the Shares pursuant to any Terms Agreement shall be deemed to have been made on the basis of the representations, warranties and agreements of the Company contained, and shall be subject to the terms and conditions set forth, in this Agreement and such Terms Agreement. Any such Terms Agreement shall specify the number of the Shares to be purchased by the applicable Agent pursuant thereto, the price to be paid to the Company for such Shares, any provisions relating to rights of, and default by, underwriters, if any, acting together with such Agent in the reoffering of the Shares, and the time and date (each such time and date being referred to herein as a “ Principal Settlement Date ”; and, together with any Agency Settlement Date, a “ Settlement Date ”) and place of delivery of and payment for such Shares.

(h) Notwithstanding any other provision of this Agreement, the Company shall not offer, sell or deliver, or request the offer or sale, of any Shares pursuant to this Agreement (whether in an Agency Transaction or a Principal Transaction) and, by notice to each Agent given by either email (with receipt confirmed by telephone) or telephone (confirmed promptly by email), shall cancel any instructions for the offer or sale of any Shares, and none of the Agents shall be obligated to offer or sell any Shares, (i) during any period in which the Company’s insider trading policy, as it exists on the date of this Agreement, would prohibit the purchases or sales of the Company’s Common Stock by any of its officers or directors, (ii) during any period in which the Company is, or could be deemed to be, in possession of material non-public information or (iii) at any time from and including the date on which the Company shall issue a press release containing, or shall otherwise publicly announce, its earnings, revenues or other results of operations (an “ Earnings Announcement ”) through and including the time that is 24 hours after the time that the Company files a Quarterly Report on Form 10-Q or an Annual Report on Form 10-K that includes consolidated financial statements as of and for the same period or periods, as the case may be, covered by such Earnings Announcement.

(i) The Company agrees that any offer to sell, any solicitation of an offer to buy, or any sales of Shares by the Company shall only be effected by or through only one Agent on any Exchange Business Day.

(j) Anything in this Agreement to the contrary notwithstanding, the Company shall not authorize the issuance and sale of, and no Agent, as sales agent, shall be obligated to use its commercially reasonable efforts, consistent with its normal trading and sales practices, to sell, any Shares at a price lower than the minimum price, or in a number or with an aggregate gross or net sales price in excess of the number or aggregate gross or net sales price, as the case may be, authorized from time to time to be issued and sold under this Agreement and any Terms Agreement, in each case by the Company’s board of directors or, if permitted by applicable law

and the Company’s charter and by-laws, a duly authorized committee thereof, or in a number in excess of the number of Shares approved for listing on the Exchange , or in excess of the number or amount of Shares available for issuance on the Registration Statement or as to which the Company has paid the applicable registration fee, it being understood and agreed by the parties hereto that compliance with any such limitations shall be the sole responsibility of the Company; and under no circumstance shall the Gross Sales Price of the Shares sold pursuant to this Agreement and any Terms Agreements exceed the Maximum Amount.

3. Representations, Warranties and Agreements of the Company . The Company represents and warrants to, and agrees with, each of the Agents, on and as of (i) the date hereof, (ii) each date on which the Company receives a Transaction Acceptance (the “ Time of Acceptance ”), (iii) each date on which the Company executes and delivers a Terms Agreement, (iv) each Time of Sale (as defined in Section 3(a)), (v) each Settlement Date and (vi) each Bring-Down Delivery Date (as defined in Section 6(b)) (each such date listed in (i) through (vi), a “ Representation Date ”), as follows:

(a) The Registration Statement has been filed with the Commission not earlier than three years prior to the date hereof; there is no order preventing or suspending the use of the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus, and, to the knowledge of the Company, no proceeding for that purpose or pursuant to Section 8A of the Act against the Company or related to the offering has been initiated or threatened by the Commission; the Registration Statement complies as of the date hereof, will comply when it is initially declared effective by the Commission and, as then amended or supplemented, as of each other Representation Date will comply, in all material respects, with the requirements of the Act; the conditions to the use of Form S-3 in connection with the offering and sale of the Shares as contemplated hereby have been satisfied; the Registration Statement meets, and the offering and sale of the Shares as contemplated hereby comply with, the requirements of Rule 415 under the Act (including, without limitation, Rule 415(a)(5)); the Prospectus complied or will comply, at the time it was or will be filed with the Commission, and will comply, as then amended or supplemented, as of each Representation Date, in all material respects, with the requirements of the Act; the Registration Statement will not as of the time of its initial effectiveness, and does not and will not, as then amended or supplemented, as of each Representation Date, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; as of each Representation Date, the Prospectus, as then amended or supplemented, together with all of the then issued Permitted Free Writing Prospectuses, if any, will not contain an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, however, that the Company makes no representation or warranty with respect to any statement in or omission from the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus made in reliance upon and in conformity with information concerning the Agents and furnished in writing by or on behalf of the Agents expressly for use in the Registration Statement, the Prospectus or such Permitted Free Writing Prospectus (it being understood that such information consists solely of the information specified in Section 9(b)). As used herein, “ Time of Sale ” means (i) with respect to each offering of Shares pursuant to this Agreement, the time of the Agents’ initial entry into contracts with investors for the sale of such Shares and (ii) with respect to each offering of Shares pursuant to any relevant Terms Agreement, the time of sale of such Shares.

(b) Prior to the execution of this Agreement, the Company has not, directly or indirectly, offered or sold any of the Shares by means of any “prospectus” (within the meaning of the Act) or used any “prospectus” (within the meaning of the Act) in connection with the offer or sale of the Shares, in each case other than the Basic Prospectus. The Company represents and agrees that, unless it obtains the prior consent of each Agent, until the termination of this Agreement, it has not made and will not make any offer relating to the Shares that would constitute an “issuer free writing prospectus” (as defined in Rule 433 under the Act) or that would otherwise constitute a “free writing prospectus” (as defined in Rule 405 under the Act) other than any Permitted Free Writing Prospectus. Any such free writing prospectus relating to the Shares consented to by each Agent (including any Free Writing Prospectus prepared by the Company solely for use in connection with the offering contemplated by a particular Terms Agreement) is hereinafter referred to as a “ Permitted Free Writing Prospectus ”. The Company has complied and will comply in all material respects with the requirements of Rule 433 under the Act applicable to any Permitted Free Writing Prospectus, including timely filing with the Commission where required, legending and record keeping. The conditions set forth in one or more of subclauses (i) through (iv), inclusive, of Rule 433(b)(1) under the Act are satisfied, and the registration statement relating to the offering of the Shares contemplated hereby, as initially filed with the Commission, includes a prospectus that, other than by reason of Rule 433 under the Act, satisfies the requirements of Section 10 of the Act; the Company is not disqualified, by reason of Rule 164(f) or (g) under the Act, from using, in connection with the offer and sale of the Shares, “free writing prospectuses” (as defined in Rule 405 under the Act) pursuant to Rules 164 and 433 under the Act; the Company was not as of each eligibility determination date for purposes of Rules 164 and 433 under the Act with respect to the offering of the Shares contemplated by the Registration Statement and this Agreement and is not an “ineligible issuer”. The Company has paid or, no later than the business day after the date of this Agreement, will pay the registration fee for the offering of the Maximum Amount of Shares pursuant to Rule 457 under the Act.

(c) The Incorporated Documents, when they were filed with the Commission (or, if any amendment with respect to any such document was filed, when such amendment was filed), conformed in all material respects to the requirements of the Act or the Exchange Act, as applicable, and none of such documents contained any untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading; and any further documents so filed during the Term and incorporated by reference in the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus, when such documents become effective or are filed with the Commission, as the case may be, will conform in all material respects to the requirements of the Act or the Exchange Act, as applicable, and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading.

(d) The financial statements of the Company and its subsidiaries and the related notes thereto included or incorporated by reference in the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus comply in all material respects with the applicable requirements of the Act and the Exchange Act, as applicable, and present fairly in all material respects the consolidated financial position of the Company and its subsidiaries as of the dates

indicated and the results of their operations and the changes in their cash flows for the periods specified; the financial statements of any other business or entity and its consolidated subsidiaries (if any) and the related notes thereto included or incorporated by reference in the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus comply in all material respects with the applicable requirements of the Act or the Exchange Act, as applicable, and present fairly in all material respects the consolidated (if applicable) financial position of such entity or business, as the case may be, and its subsidiaries (if any) as of the dates indicated and the results of its or their, as the case may be, operations and the changes in its or their, as the case may be, cash flows for the periods specified; and all such financial statements have been prepared in conformity with generally accepted accounting principles (“ GAAP ”) applied on a consistent basis throughout the periods covered thereby, and all supporting schedules to such financial statements included or incorporated by reference in the Registration Statement fairly present in all material respects the information required to be stated therein. Any pro forma financial statements and related notes included or incorporated by reference in the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus comply in all material respects with the applicable requirements of the Act and the Exchange Act, as applicable, present fairly in all material respects the information shown therein, have been prepared in accordance with the Commission’s rules and guidelines with respect to pro forma financial statements and have been properly compiled on the bases described therein, and the assumptions used in the preparation thereof are reasonable and the adjustments used therein are appropriate to give effect to the transactions and circumstances referred to therein.

(e) Since the respective dates as of which information is given in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus, except as otherwise stated therein, (i) there has not been any change in the capital stock (other than the issuance of shares of Common Stock upon exercise of stock options issued under, and the grant of options and awards under, equity incentive plans described in the Registration Statement and the Prospectus and the issuance of Shares pursuant to this Agreement) or short-term debt or long-term debt (except for borrowings and the repayment of borrowings in the ordinary course of business and pursuant to the Company’s loan and security agreement with Solar Capital Ltd.) of the Company or any of its subsidiaries, or any dividend or distribution of any kind declared, set aside for payment, paid or made by the Company on any class of capital stock, or any material adverse change, or any development that would reasonably be expected to result in a prospective material adverse change, in or affecting the business, properties, management, financial position, stockholders’ equity, results of operations or prospects of the Company and its subsidiaries taken as a whole; (ii) neither the Company nor any of its subsidiaries has entered into any transaction or agreement (whether or not in the ordinary course of business) that is material to the Company and its subsidiaries taken as a whole or incurred any liability or obligation, direct or contingent, that is material to the Company and its subsidiaries taken as a whole; and (iii) neither the Company nor any of its subsidiaries has sustained any loss or interference with its business that is material to the Company and its subsidiaries taken as a whole and that is either from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor disturbance or dispute or any action, order or decree of any court or arbitrator or governmental or regulatory authority.

(f) The Company and each of its subsidiaries have been duly organized and are validly existing and in good standing under the laws of their respective jurisdictions of organization, are duly qualified to do business and are in good standing in each jurisdiction in

which their respective ownership or lease of property or the conduct of their respective businesses requires such qualification, and have all power and authority necessary to own or hold their respective properties and to conduct the businesses in which they are engaged, except where the failure to be so qualified or in good standing or have such power or authority would not, individually or in the aggregate, have a material adverse effect on the business, properties, management, financial position, stockholders’ equity, results of operations or prospects of the Company and its subsidiaries taken as a whole or on the performance by the Company of its obligations under this Agreement or any Terms Agreement (a “ Material Adverse Effect ”). The Company does not own or control, directly or indirectly, any corporation, association or other entity other than the subsidiaries listed in Exhibit 21 to the Company’s most recent Annual Report on Form 10-K incorporated by reference in the Registration Statement.

(g) On the date of the initial filing of the Registration Statement with the Commission, the Company is an “emerging growth company,” as defined in Section 2(a) of the Securities Act.

(h) The Company has an authorized capitalization as set forth in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus; all the outstanding shares of capital stock of the Company have been duly and validly authorized and issued and are fully paid and non-assessable and were not issued in violation of any preemptive or similar rights; except as described in or expressly contemplated by the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus, there are no outstanding rights (including, without limitation, pre-emptive or similar rights), warrants or options to acquire, or instruments convertible into or exchangeable for, any shares of capital stock or other equity interests of the Company or any of its subsidiaries, nor any contracts, commitments, agreements, understandings or arrangements of any kind relating to the issuance of any capital stock or other equity interest of the Company or any such subsidiary, any such convertible or exchangeable securities or any such rights, warrants or options; and the capital stock of the Company and the Company’s charter and by-laws conform in all material respects to the descriptions thereof contained in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus; and all the outstanding shares of capital stock or other equity interests of each subsidiary owned, directly or indirectly, by the Company have been duly and validly authorized and issued, are fully paid and non-assessable and are owned directly or indirectly by the Company, free and clear of any lien, charge, encumbrance, security interest, restriction on voting or transfer or any other claim of any third party.

(i) With respect to the stock options (the “ Stock Options ”) granted pursuant to the stock-based compensation plans of the Company and its subsidiaries (the “ Company Stock Plan s”), (i) each Stock Option intended to qualify as an “incentive stock option” under Section 422 of the Internal Revenue Code of 1986, as amended (the “ Code ”), so qualifies, (ii) each grant of a Stock Option was duly authorized no later than the date on which the grant of such Stock Option was by its terms to be effective (the “ Grant Date ”) by all necessary corporate action, including, as applicable, approval by the board of directors of the Company (or a duly constituted and authorized committee thereof) and any required stockholder approval by the necessary number of votes or written consents, and the award agreement governing such grant (if any) was duly executed and delivered by each party thereto, (iii) each such grant was made in all material respects in accordance with the terms of the Company Stock Plans and all applicable

laws and regulatory rules or requirements, including the rules of the Exchange, and (iv) each such grant was properly accounted for in accordance with GAAP in the financial statements (including the related notes) of the Company and disclosed in the Company’s filings with the Commission in accordance with the Exchange Act and all other applicable laws. The Company has not knowingly granted, and there is no and has been no policy or practice of the Company of granting, Stock Options prior to, or otherwise coordinating the grant of Stock Options with, the release or other public announcement of material information regarding the Company or its subsidiaries or their results of operations or prospects.

(j) This Agreement has been duly authorized, executed and delivered by the Company and any Terms Agreement will have been duly authorized, executed and delivered by the Company.

(k) The Shares to be issued and sold by the Company hereunder or under any Terms Agreement have been duly authorized by the Company and, when issued and delivered and paid for as provided herein or in any Terms Agreement, as the case may be, will be duly and validly issued, will be fully paid and nonassessable and will conform in all material respects to the descriptions thereof in the Registration Statement, the Prospectus, and any Permitted Free Writing Prospectus; and the issuance and sale of the Shares are not and will not be subject to any preemptive or similar rights, except for such rights as have been waived.

(l) The Company has or will have full right, power and authority to execute and deliver this Agreement and any Terms Agreement and perform its obligations hereunder or thereunder, including the Company’s issuance, sale and delivery of the Shares as provided herein and therein; and all action required to be taken for the due and proper authorization, execution and delivery by each of the Company of this Agreement and any Terms Agreement and the consummation by it of the transactions contemplated hereby and thereby has been duly and validly taken (or, in the case of any Terms Agreement, such action will have been duly and validly authorized).

(m) This Agreement conforms and each Terms Agreement will conform in all material respects to the description thereof contained in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus.

(n) Neither the Company nor any of its subsidiaries is (i) in violation of its charter or by-laws or other Organizational Documents (as defined below); (ii) in default, and no event has occurred that, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject; or (iii) in violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of clauses (ii) and (iii) above, for any such default or violation that would not, individually or in the aggregate, have a Material Adverse Effect. As used herein, the term “ Organizational Documents ” means, (i) with respect to a corporation, its charter and by-laws, (ii) with respect to a limited or general partnership, its partnership agreement and certificate of partnership (or similar document), (iii) with respect to a

limited liability company, its limited liability company agreement and certificate of limited liability company (or similar document), and (iv) with respect to any other entity, its similar organizational documents.

(o) The execution, delivery and performance by the Company of this Agreement and any Terms Agreement, the issuance and sale of the Shares, the compliance by the Company with the terms hereof and of any Terms Agreement and the consummation of the transactions contemplated hereby or by any Terms Agreement will not (i) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, result in the termination, modification or acceleration of, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries pursuant to, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, (ii) result in any violation of the provisions of the charter or by-laws or other Organizational Documents of the Company or any of its subsidiaries or (iii) result in the violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of clauses (i) and (iii) above, for any such conflicts, breaches, violations, defaults, liens, charges or encumbrances that would not, individually or in the aggregate, have a Material Adverse Effect.

(p) No consent, approval, authorization, order, license, registration or qualification of or with any court or arbitrator or governmental or regulatory authority is required for the execution, delivery and performance by the Company of this Agreement or any Terms Agreement, the issuance and sale of the Shares, compliance by the Company with the terms of this Agreement or of any Terms Agreement and the consummation of the transactions contemplated by this Agreement or any Terms Agreement, except as have been made or obtained, except as may be required by and made in accordance with or obtained under state securities laws or regulations, and except for such filings of Permitted Free Writing Prospectuses and any amendments or supplements to the Registration Statement or the Prospectus or any documents incorporated or deemed to be incorporated by reference therein as may be required by the Act or the Exchange Act from time to time, and except for such filings as the Exchange may require from time to time.

(q) Except as described in the Registration Statement and the Prospectus, there are no legal, governmental or regulatory investigations, actions, demands, claims, suits arbitrations, inquiries or proceedings (“ Actions ”) pending to which the Company or any of its subsidiaries is or may be a party or to which any property of the Company or any of its subsidiaries is or may be the subject that, individually or in the aggregate, if determined adversely to the Company or any of its subsidiaries, could reasonably be expected to have a Material Adverse Effect; no such Actions are threatened or, to the knowledge of the Company, contemplated by any governmental or regulatory authority or threatened by others; and (i) there are no current or pending Actions that are required under the Act or the Exchange Act to be described in the Registration Statement or the Prospectus or any document incorporated by reference therein that are not so described and (ii) there are no statutes, regulations or contracts or other documents that are required under the Act or the Exchange Act to be filed as exhibits to the Registration Statement or any document incorporated by reference therein or described in the Registration Statement or the

Prospectus or any document incorporated by reference therein that are not so filed as exhibits or so described.

(r) PricewaterhouseCoopers LLP, whose report on the consolidated financial statements of the Company and its consolidated subsidiaries is included or incorporated by reference in the Registration Statement and the Prospectus, is an independent registered public accounting firm with respect to the Company and its subsidiaries within the applicable rules and regulations adopted by the Commission and the Public Company Accounting Oversight Board (“ PCAOB ”) and as required by the Act. Each other independent registered public accounting firm, if any, that has certified or reported on any other financial statements included or incorporated by reference in the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus is an independent registered public accounting firm with respect to the Company and its subsidiaries or other appropriate entity, as applicable, within the applicable rules and regulations adopted by the Commission and the PCAOB and as required by the Act.

(s) (i) Except as otherwise set forth in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus, the Company and its subsidiaries have good and marketable title in fee simple to, or have valid and marketable rights to lease or otherwise use, all items of real and personal property that are material to the respective businesses of the Company and its subsidiaries, in each case free and clear of all liens, encumbrances, claims and defects and imperfections of title except those that (i) do not materially interfere with the use made and proposed to be made of such property by the Company and its subsidiaries or (ii) would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.

(t) The Company and its subsidiaries own, have valid and enforceable license to, or otherwise have the right to use all patents, patent applications, trademarks (both registered and unregistered), service marks, trade names, trademark registrations, service mark registrations, domain names and other source indicators, copyrights and copyrightable works, know-how, trade secrets, systems, procedures, proprietary or confidential information and all other intellectual property and proprietary rights, including registrations and applications for registration thereof (collectively, “ Intellectual Property ”) which are necessary for or material to the conduct of their respective businesses, or which are described in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus as being owned or licensed by them (collectively, “ Company Intellectual Property ”). To the knowledge of the Company and its subsidiaries, (i) the Company’s and its subsidiaries’ conduct of their respective businesses does not infringe, misappropriate or otherwise violate any Intellectual Property of any third party; and (ii) the Company Intellectual Property is not being infringed, misappropriated or otherwise violated by any third party. There is no pending or, to the knowledge of the Company or its subsidiaries, threatened action, suit, proceeding or claim by others: (A) challenging the Company’s or its subsidiaries rights in or to any Company Intellectual Property, and the Company and its subsidiaries are unaware of any facts which would form a reasonable basis for any such action, suit, proceeding or claim; (B) challenging the validity, enforceability or scope of any Company Intellectual Property, and the Company and its subsidiaries are unaware of any facts which would form a reasonable basis for any such action, suit, proceeding or claim; or (C) asserting that the Company or any of its subsidiaries infringes or otherwise violates, or would, upon the commercialization of any product or service described in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus as under development, infringe or violate, any Intellectual Property of third parties, and

the Company and its subsidiaries have not received any notice of, and is unaware of any facts which would form a reasonable basis for any such action, suit, proceeding or claim. The Company and its subsidiaries have complied with the terms of each agreement pursuant to which Company Intellectual Property has been licensed to the Company or any subsidiary, and all such agreements are in full force and effect. To the knowledge of the Company and its subsidiaries, no technology employed by the Company or its subsidiaries has been obtained or is being used by the Company or its subsidiaries in violation of any contractual or legal obligation binding on the Company, its subsidiaries, or any of their officers, directors, employees, or contractors, which violation relates to the breach of a confidentiality obligation, an obligation to assign Intellectual Property to a previous employer, or an obligation otherwise not to use the Intellectual Property of any third party. The product candidates described in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus as under development by the Company or any subsidiary fall within the scope of the claims of one or more patents owned by, or exclusively licensed to, the Company or any subsidiary. To the knowledge of the Company and its subsidiaries, (A) there is no patent or published patent application in the U.S. or other jurisdiction that contains claims that interfere with the issued or pending claims of any patent within the Company Intellectual Property; (B) there is no prior art of which the Company is aware that may render any patent within the Company Intellectual Property invalid or any patent application within the Company Intellectual Property unpatentable; (C) there are no defects in any of the patents or patent applications included in the Company Intellectual Property; and (D) the duty of candor and good faith as required by the United States Patent and Trademark Office during the prosecution of the United States patents and patent applications within the Company Intellectual Property have been complied with, and in all foreign offices having similar requirements, such requirements have been complied with.

(u) No relationship, direct or indirect, exists between or among the Company or any of its subsidiaries, on the one hand, and the directors, officers, stockholders, customers, suppliers or other affiliates of the Company or any of its subsidiaries, on the other, that is required by the Act to be described in the Registration Statement and the Prospectus and that is not so described in such documents and in any Permitted Free Writing Prospectus.

(v) The Company is not and, after giving effect to the offering and sale of the Shares and the application of the net proceeds thereof as described in the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus, the Company will not be required to register as an “investment company” within the meaning of the Investment Company Act of 1940, as amended, and the rules and regulations of the Commission thereunder (collectively, the “ Investment Company Act ”) or an entity “controlled” by an “investment company” within the meaning of the Investment Company Act.

(w) The Company and its subsidiaries have paid all federal, state, local and foreign taxes and filed all tax returns required to be paid or filed through the date hereof, except where the failure to pay or file any such taxes would not have a Material Adverse Effect; and except as otherwise disclosed in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus, there is no tax deficiency that has been, or would reasonably be expected to be, asserted against the Company or any of its subsidiaries or any of their respective properties or assets and which could have a Material Adverse Effect.

(x) The Company and its subsidiaries possess all licenses, sub-licenses, certificates, permits and other authorizations (collectively, “ Permits ”) issued by, and have made all declarations and filings with or required by, the appropriate federal, state, local or foreign governmental or regulatory authorities, including without limitation, the U.S. Food and Drug Administration or any component thereof (collectively, “ Regulatory Authorities ”), that are necessary for the ownership or lease of their respective properties or the conduct of their respective businesses as described in each of the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus, except where the failure to possess or make the same would not, individually or in the aggregate, have a Material Adverse Effect. The Company is in compliance with the terms and conditions of all such Permits, except where the failure to comply would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. All of the Permits are valid and in full force and effect. The Company has fulfilled and performed all of its material obligations with respect to the Permits. To the Company’s knowledge, no event has occurred which allows, or after notice or lapse of time would allow, revocation or termination thereof or results in any other material impairment of the rights of the holder of any Permit. Except as described in each of the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus, neither the Company nor any of its subsidiaries has received notice of any revocation or modification of, or notice of any proceedings relating to the revocation or modification of, any such Permit or has any reason to believe that any such Permit will not be renewed in the ordinary course, except where such revocation, modification or nonrenewal would not have a Material Adverse Effect.

(y) The Company, its or its subsidiaries’ directors, officers, and to the knowledge of the Company, its or its subsidiaries’ employees and agents, are, and at all times have been, in compliance with all health care laws applicable to the Company or its product candidates or activities, including, without limitation, the Federal Food, Drug, and Cosmetic Act (the “ FDCA ”) (21 U.S.C. § 301 et seq.), the federal Anti-kickback Statute (42 U.S.C. § 1320a-7b(b)), the federal Physician Payments Sunshine Act (42 U.S.C. § 1320a-7h), the civil False Claims Act (31 U.S.C. §§3729 et seq.), all criminal laws relating to health care fraud and abuse, including but not limited to the criminal False Claims Law (42 U.S.C. § 1320a-7b(a)), 18 U.S.C. Sections 286 and 287, and the health care fraud criminal provisions under the U.S. Health Insurance Portability and Accountability Act of 1996 (“ HIPAA ”) (42 U.S.C. Section 1320d et seq.), HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act (42 U.S.C. §§ 17921 et seq.), the exclusion laws (42 U.S.C. § 1320a-7), the civil monetary penalties law (42 U.S.C. § 1320a-7a), Medicare (Title XVIII of the Social Security Act), Medicaid (Title XIX of the Social Security Act), the Public Health Service Act (42 U.S.C. § 201 et seq.), any similar local, state or federal laws, and the regulations promulgated pursuant to such laws (collectively, the “ Health Care Laws ”), except where failure to be so in compliance have not, and would not reasonably be expected to have a Material Adverse Effect. The Company has not received any FDA Form 483, notice of adverse finding, warning letter, untitled letter or other correspondence or notice from any Regulatory Authority or governmental authority alleging or asserting noncompliance with any Health Care Laws applicable to the Company or its subsidiaries. Neither the Company, nor, to the knowledge of the Company, any of its or its subsidiaries’ employees, officers or directors has been excluded, suspended or debarred from participation in any U.S. federal health care program or human clinical research or, is subject to a governmental inquiry, investigation, proceeding, or other similar action that could reasonably be expected to result in debarment, suspension, or exclusion

(z) The pre-clinical, clinical (as applicable) and other studies, tests, trials and research conducted by or on behalf of or sponsored by the Company are being and have been conducted in compliance with the experimental protocols established for each study, test, trial or research and in accordance, in all material respects, with the Health Care Laws, including, but not limited to, the FDCA and its applicable implementing regulations at 21 C.F.R. Parts 50, 54, 56, 58 and 312. The published descriptions of the results of such studies, tests and research are accurate and complete in all material respects and fairly present the data derived from such studies, tests and research, and the Company does not have any knowledge of any other studies, tests or research the results of which are materially inconsistent with or otherwise reasonably call into question the results described or referred to in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus. The Company has not received any notices or other correspondence from any Regulatory Authority with respect to any clinical or pre-clinical studies, tests or research that are, or whose results of which are, described the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus that require the termination, suspension, or material modification of such studies, tests or research.

(aa) No labor disturbance by or dispute with employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is contemplated or threatened, and the Company is not aware of any existing or imminent labor disturbance by, or dispute with, the employees of any of its or its subsidiaries’ principal suppliers, contractors or customers, except as would not, individually or in the aggregate, have a Material Adverse Effect. Neither the Company nor any of its subsidiaries has received any notice of cancellation or termination with respect to any collective bargaining agreement to which it is a party.

(bb) (i) The Company and its subsidiaries (x) are in compliance with all, and have not violated any, applicable federal, state, local and foreign laws (including common law), rules, regulations, requirements, decisions, judgments, decrees, orders and other legally enforceable requirements relating to pollution or the protection of human health or safety, the environment, natural resources, hazardous or toxic substances or wastes, pollutants or contaminants (collectively, “ Environmental Laws ”); (y) have received and are in compliance with all, and have not violated any, permits, licenses, certificates or other authorizations or approvals required of them under any Environmental Laws to conduct their respective businesses; and (z) have not received notice of any actual or potential liability or obligation under or relating to, or any actual or potential violation of, any Environmental Laws, including for the investigation or remediation of any disposal or release of hazardous or toxic substances or wastes, pollutants or contaminants, and have no knowledge of any event or condition that would reasonably be expected to result in any such notice, and (ii) there are no costs or liabilities associated with Environmental Laws of or relating to the Company or its subsidiaries, except in the case of each of (i) and (ii) above, for any such matter as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and (iii) except as described in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus, (x) there is no proceeding that is pending, or to the Company’s knowledge, contemplated, against the Company or any of its subsidiaries under any Environmental Laws in which a governmental entity is also a party, other than such proceeding regarding which it is reasonably believed no monetary sanctions of $100,000 or more will be imposed, (y) the Company and its subsidiaries are not aware of any facts or issues regarding compliance with Environmental Laws, or liabilities or other obligations under Environmental Laws or concerning hazardous or toxic substances or wastes, pollutants or

contaminants, that could reasonably be expected to have a material effect on the capital expenditures, earnings or competitive position of the Company and its subsidiaries, and (z) none of the Company or its subsidiaries anticipates material capital expenditures relating to any Environmental Laws .

(cc) (i) Each employee benefit plan, within the meaning of Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended (“ ERISA ”), for which the Company or any member of its “ Controlled Group ” (defined as any entity, whether or not incorporated, that is under common control with the Company within the meaning of Section 4001(a)(14) of ERISA or any entity that would be regarded as a single employer with the Company under Section 414(b), (c), (m) or (o) of the Code) would have any liability (each, a “ Plan ”) has been maintained in compliance with its terms and the requirements of any applicable statutes, orders, rules and regulations, including but not limited to ERISA and the Code; (ii) no prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred with respect to any Plan, excluding transactions effected pursuant to a statutory or administrative exemption; (iii) for each Plan that is subject to the funding rules of Section 412 of the Code or Section 302 of ERISA, no Plan has failed (whether or not waived), or is reasonably expected to fail, to satisfy the minimum funding standards (within the meaning of Section 302 of ERISA or Section 412 of the Code) applicable to such Plan; (iv) no Plan is, or is reasonably expected to be, in “at risk status” (within the meaning of Section 303(i) of ERISA) and no Plan that is a “multiemployer plan” within the meaning of Section 4001(a)(3) of ERISA is in “endangered status” or “critical status” (within the meaning of Sections 304 and 305 of ERISA); (v) the fair market value of the assets of each Plan exceeds the present value of all benefits accrued under such Plan (determined based on those assumptions used to fund such Plan); (vi) no “reportable event” (within the meaning of Section 4043(c) of ERISA and the regulations promulgated thereunder) has occurred or is reasonably expected to occur; (vii) each Plan that is intended to be qualified under Section 401(a) of the Code is so qualified, and nothing has occurred, whether by action or by failure to act, which would cause the loss of such qualification; (viii) neither the Company nor any member of the Controlled Group has incurred, nor reasonably expects to incur, any liability under Title IV of ERISA (other than contributions to the Plan or premiums to the Pension Benefit Guarantee Corporation, in the ordinary course and without default) in respect of a Plan (including a “multiemployer plan” within the meaning of Section 4001(a)(3) of ERISA); and (ix) none of the following events has occurred or is reasonably likely to occur: (A) a material increase in the aggregate amount of contributions required to be made to all Plans by the Company or its Controlled Group affiliates in the current fiscal year of the Company and its Controlled Group affiliates compared to the amount of such contributions made in the Company’s and its Controlled Group affiliates’ most recently completed fiscal year; or (B) a material increase in the Company and its subsidiaries’ “accumulated post-retirement benefit obligations” (within the meaning of Accounting Standards Codification Topic 715-60) compared to the amount of such obligations in the Company and its subsidiaries’ most recently completed fiscal year, except in each case with respect to the events or conditions set forth in (i) through (ix) hereof, as would not, individually or in the aggregate, have a Material Adverse Effect.

(dd) The Company and its subsidiaries maintain an effective system of “disclosure controls and procedures” (as defined in Rule 13a-15(e) of the Exchange Act) that complies with the requirements of the Exchange Act and that has been designed to ensure that information

required to be disclosed by the Company in reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the Commission’s rules and forms, including controls and procedures designed to ensure that such information is accumulated and communicated to the Company’s management as appropriate to allow timely decisions regarding required disclosure. The Company and its subsidiaries have carried out evaluations of the effectiveness of their disclosure controls and procedures as required by Rule 13a-15 of the Exchange Act, and as of September 30, 2018 and as of the last day of each of the Company’s fiscal quarters ended thereafter, such disclosure controls and procedures were effective to perform the functions for which they were established.

(ee) The Company and its subsidiaries maintain systems of “internal control over financial reporting” (as defined in Rule 13a-15(f) of the Exchange Act) that comply with the requirements of the Exchange Act and have been designed by, or under the supervision of, their respective principal executive and principal financial officers, or persons performing similar functions, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with GAAP. The Company and its subsidiaries maintain internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with GAAP and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences. Based on the Company’s most recent evaluation of its internal controls over financial reporting pursuant to Rule 13a-15(c) of the Exchange Act, there are no material weaknesses in the Company’s internal control over financial reporting. The Company’s auditors and the Audit Committee of the Board of Directors of the Company have been advised of: (i) all significant deficiencies and material weaknesses in the design or operation of internal controls over financial reporting which have adversely affected or are reasonably likely to adversely affect the Company’s ability to record, process, summarize and report financial information; and (ii) to the knowledge of the Company, any fraud, whether or not material, that involves management or other employees who have a significant role in the Company’s internal controls over financial reporting.

(ff) The Registration Statement and the documents incorporated by reference therein include and incorporate by reference all interactive data in eXtensible Business Reporting Language (“ XBRL Data ”) required to be included therein; and the XBRL Data included or incorporated by reference in the Registration Statement or the documents incorporated by reference therein fairly presents the information called for in all material respects and has been prepared in accordance with the Commission’s rules and guidelines applicable thereto.

(gg) The Company and its subsidiaries have insurance covering their respective properties, operations, personnel and businesses, including business interruption insurance, which insurance is in amounts and insures against such losses and risks as are generally maintained by similarly situated companies and which the Company believes are reasonably adequate to protect the Company and its subsidiaries and their respective businesses; and neither the Company nor any of its subsidiaries has (i) received notice from any insurer or agent of such insurer that capital improvements or other expenditures are required or necessary to be made in

order to continue such insurance or (ii) knowledge of any events that have occurred, or circumstances that exist, with respect to the Company that would cause it to be unable to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage at reasonable cost from similar insurers as may be necessary to continue its business.

(hh) Neither the Company nor any of its subsidiaries nor any director, officer or employee of the Company or any of its subsidiaries or affiliates nor, to the knowledge of the Company, any agent, affiliate or other person associated with or acting on behalf of the Company or any of its subsidiaries or affiliates (i) has used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity; (ii) has made or taken an act in furtherance of an offer, promise or authorization of any direct or indirect unlawful payment or benefit to any foreign or domestic government official or employee, including of any government-owned or controlled entity or of a public international organization, or any person acting in an official capacity for or on behalf of any of the foregoing, or any political party or party official or candidate for political office; (iii) has violated or is in violation of any provision of the Foreign Corrupt Practices Act of 1977, as amended, or any applicable law or regulation implementing the OECD Convention on Combating Bribery of Foreign Public Officials in International Business Transactions, or has committed an offence under the Bribery Act 2010 of the United Kingdom, or any other applicable anti-bribery or anti-corruption law; or (iv) has made, offered, agreed, requested or taken an act in furtherance of any unlawful bribe or other unlawful benefit, including, without limitation, any rebate, payoff, influence payment, kickback or other unlawful or improper payment or benefit. The Company and its subsidiaries and affiliates have conducted their businesses in compliance with applicable anti-corruption laws and have instituted, maintain and enforce, and will continue to maintain and enforce policies and procedures designed to promote and ensure compliance with all applicable anti-bribery and anti-corruption laws. Neither the Company nor its subsidiaries will use, directly or indirectly, the proceeds of the offering in furtherance of an offer, payment, promise to pay, or authorization of the payment or giving of money, or anything else of value, to any person in violation of any applicable anti-corruption laws.

(ii) The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with financial recordkeeping and reporting requirements applicable to such entities, including those of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the applicable money laundering statutes of all jurisdictions where the Company or any of its subsidiaries conducts business, the rules and regulations thereunder and any related or similar rules, regulations or guidelines applicable to such entities, issued, administered or enforced by any governmental agency (collectively, the “ Anti-Money Laundering Laws ”), and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Anti-Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

(jj) Neither the Company nor any of its subsidiaries, directors, officers or employees, nor, to the knowledge of the Company, any agent, affiliate or other person associated with or acting on behalf of the Company or any of its subsidiaries is, or is owned or controlled by one or more Persons that is, (i) currently the subject or the target of any sanctions administered or enforced by the U.S. government (including, without limitation, the Office of Foreign Assets Control of the U.S. Department of the Treasury (“ OFAC ”) or the U.S. Department of State and

including, without limitation, the designation as a “specially designated national” or “blocked person”), the United Nations Security Council (“ UNSC ”), the European Union, Her Majesty’s Treasury (“ HMT ”) or other relevant sanctions authority (collectively, “Sanctions”), nor (ii) located, organized or resident in a country or territory that is the subject or target of Sanctions, including, without limitation, Crimea, Cuba, Iran, North Korea and Syria (each, a “ Sanctioned Country ”); and the Company will not directly or indirectly use the proceeds of the offering of the Shares hereunder, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity (i) to fund or facilitate any activities of or business with any person that, at the time of such funding or facilitation, is the subject or target of Sanctions, (ii) to fund or facilitate any activities of or business in any Sanctioned Country or (iii) in any other manner that will result in a violation by any person (including any person participating in the transaction, whether as underwriter, advisor, investor or otherwise) of Sanctions. For the past five years, the Company and its subsidiaries have not knowingly engaged in and are not now knowingly engaged in any dealings or transactions with any person that at the time of the dealing or transaction is or was the subject or the target of Sanctions or with any Sanctioned Country.

(kk) No subsidiary of the Company is currently prohibited, directly or indirectly, under any agreement or other instrument to which it is a party or is subject, from paying any dividends to the Company, from making any other distribution on such subsidiary’s capital stock or similar ownership interest, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s properties or assets to the Company or any other subsidiary of the Company.

(ll) Neither the Company nor any of its subsidiaries is a party to any contract, agreement or understanding with any person (other than this Agreement or any Terms Agreement) that would give rise to a valid claim against the Company or any of its subsidiaries or any Agent for a brokerage commission, finder’s fee or like payment in connection with the offering and sale of the Shares.

(mm) No person has the right to require the Company or any of its subsidiaries to register any securities for sale under the Act by reason of the filing of the Registration Statement with the Commission or the offering, issuance or sale of the Shares.

(nn) Neither the Company nor any subsidiary or affiliate of the Company has taken nor will the Company or any subsidiary or affiliate of the Company take, directly or indirectly, any action which is designed to or which has constituted or which would reasonably be expected to cause or result in the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Shares.

(oo) The application of the proceeds received by the Company from the issuance, sale and delivery of the Shares as described in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus will not violate Regulation T, U or X of the Board of Governors of the Federal Reserve System or any other regulation of such Board of Governors.

(pp) There is and has been no failure on the part of the Company or, to the knowledge of the Company, any of the Company’s directors or officers, in their capacities as such, to

comply with any provision of the Sarbanes-Oxley Act of 2002 and the rules and regulations promulgated in connection therewith (the “ Sarbanes-Oxley Act ”), including Section 402 related to loans and Sections 302 and 906 related to certifications.

(qq) No forward-looking statement (within the meaning of Section 27A of the Act and Section 21E of the Exchange Act) contained or incorporated by reference in the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus has been made or reaffirmed without a reasonable basis or has been disclosed other than in good faith.

(rr) Nothing has come to the attention of the Company that has caused the Company to believe that the statistical and market-related data included in the Registration Statement, any Permitted Free Writing Prospectus and the Prospectus is not based on or derived from sources that are reliable and accurate in all material respects.

(ss) All of the Shares that have been or may be sold under this Agreement and any Terms Agreement will be approved for listing on the Exchange prior to any sales hereunder.

(tt) The Common Stock is an “actively-traded security” excepted from the requirements of Rule 101 of Regulation M under the Exchange Act by Rule 101 (c)(1) thereunder.

(uu) Cybersecurity; Data Protection. (i)(x) Except as disclosed in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus, to the Company’s knowledge, there has been no security breach or other compromise of or relating to any of the Company’s or its subsidiaries’ information technology and computer systems, networks, hardware, software, data (including the data of their respective customers, employees, suppliers, vendors and any third party data maintained by or on behalf of them), equipment or technology (collectively, “ IT Systems and Data ”) and (y) the Company and its subsidiaries have not been notified of, and have no knowledge of any event or condition that would reasonably be expected to result in, any security breach or other compromise to their IT Systems and Data; (ii) the Company and its subsidiaries are presently in compliance with all applicable laws or statutes and all judgments, orders, rules and regulations of any court or arbitrator or governmental or regulatory authority, internal policies and contractual obligations relating to the privacy and security of IT Systems and Data and to the protection of such IT Systems and Data from unauthorized use, access, misappropriation or modification, except as would not, in the case of this clause (ii), individually or in the aggregate, have a Material Adverse Effect; and (iii) the Company and its subsidiaries have implemented backup and disaster recovery technology consistent with industry standards and practices.

(vv) Any certificate signed by any officer, general partner, managing member or other authorized representative of the Company or any subsidiary of the Company and delivered to the Agents or to counsel to the Agents pursuant to or in connection with this Agreement or any Terms Agreement shall be deemed a representation and warranty by the Company to the Agents as to the matters covered thereby.

4. Certain Covenants of the Company. The Company hereby agrees with each of the Agents:

(a) For so long as the delivery of a prospectus is required (whether physically or through compliance with Rule 172 under the Act or any similar rule) in connection with the offering or sale of Shares, before using or filing any Permitted Free Writing Prospectus and before using or filing any amendment or supplement to the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus (in each case, other than due to the filing of an Incorporated Document), to furnish to each Agent a copy of each such proposed Permitted Free Writing Prospectus, amendment or supplement within a reasonable period of time before filing with the Commission or using any such Permitted Free Writing Prospectus, amendment or supplement and the Company will not use or file any such Permitted Free Writing Prospectus or any such proposed amendment or supplement to which any Agent reasonably objects, unless the Company’s legal counsel has advised the Company that use or filing of such document is required by law; and the Company will not use or file any such Permitted Free Writing Prospectus or proposed, amendment or supplement to which any Agent reasonably objects unless the Company’s legal counsel has advised the Company that use or filing of such document is required by law.

(b) To file the Prospectus, each Prospectus Supplement and any other amendments or supplements to the Prospectus pursuant to, and within the time period required by, Rule 424(b) under the Act (without reference to Rule 424(b)(8)) and to file any Permitted Free Writing Prospectus to the extent required by Rule 433 under the Act and to provide copies of the Prospectus, each Prospectus Supplement, any other amendments or supplements to the Prospectus and each Permitted Free Writing Prospectus (to the extent not previously delivered or filed on the Commission’s Electronic Data Gathering, Analysis and Retrieval system or any successor system thereto (collectively, “ EDGAR ”)) to each Agent via e-mail in “.pdf” format on such filing date to an e-mail account designated by each such Agent and, at any Agent’s request, to also furnish copies of the Prospectus, each Prospectus Supplement, any other amendments or supplements to the Prospectus and each Permitted Free Writing Prospectus to each exchange or market on which sales were effected as may be required by the rules or regulations of such exchange or market.

(c) To file timely all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act for so long as the delivery of a prospectus is required (whether physically or through compliance with Rule 172 under the Act or any similar rule) in connection with the offering or sale of the Shares, and during such same period to advise each Agent, promptly after the Company receives notice thereof, (i) of the time when any amendment to the Registration Statement has been filed or has become effective or any supplement to the Prospectus or any Permitted Free Writing Prospectus or any amended Prospectus has been filed with the Commission; (ii) of the issuance by the Commission of any stop order or any order preventing or suspending the use of any prospectus relating to the Shares or the initiation or threatening of any proceeding for that purpose, pursuant to Section 8A of the Act; (iii) of the suspension of the qualification of the Shares for offering or sale in any jurisdiction or of the initiation or threatening of any proceeding for any such purpose; (iv) of any request by the Commission for the amendment of the Registration Statement or the amendment or supplementation of the Prospectus (in each case including any documents incorporated by reference therein) or for additional information; (v) of the occurrence of any event as a result of which the Prospectus or any Permitted Free Writing Prospectus as then amended or

supplemented includes any untrue statement of a material fact or omits to state a material fact required to be stated therein or necessary in order to make the statements therein, in the light of the circumstances existing when the Prospectus or any such Permitted Free Writing Prospectus is delivered to a purchaser, not misleading; and (vi) of the receipt by the Company of any notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto.

(d) In the event of the issuance of any such stop order or of any such order preventing or suspending the use of any such prospectus or suspending any such qualification, to use promptly its commercially reasonable efforts to obtain its withdrawal.

(e) To furnish such information as may be required and otherwise cooperate in qualifying the Shares for offering and sale under the securities or blue sky laws of such states or other jurisdictions as an Agent may reasonably designate and to maintain such qualifications in effect so long as required for the distribution of the Shares; provided that the Company shall not be required to qualify as a foreign corporation, become a dealer of securities, or become subject to taxation in, or to consent to the service of process under the laws of, any such state or other jurisdictions (except service of process with respect to the offering and sale of the Shares); and to promptly advise each Agent of the receipt by the Company of any notification with respect to the suspension of the qualification of the Shares for sale in any jurisdiction or the initiation of any proceeding for such purpose.

(f) To make available to each Agent at its offices in New York City, without charge, as soon as reasonably practicable after the Registration Statement becomes effective, and thereafter from time to time to furnish to each Agent, as many copies of the Prospectus and the Prospectus Supplement (or of the Prospectus or Prospectus Supplement as amended or supplemented if the Company shall have made any amendments or supplements thereto and documents incorporated by reference therein after the effective date of the Registration Statement) and each Permitted Free Writing Prospectus as such Agent may reasonably request for so long as the delivery of a prospectus is required (whether physically or through compliance with Rule 172 under the Act or any similar rule); and for so long as this Agreement is in effect, the Company will prepare and file promptly such amendment or amendments to the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus as may be necessary to comply with the requirements of Section 10(a)(3) of the Act.

(g) To furnish or make available to each Agent during the Term (i) copies of any reports or other communications which the Company shall send to its shareholders or shall from time to time publish or publicly disseminate and (ii) copies of all annual, quarterly and current reports filed with the Commission on Forms 10-K, 10-Q and 8-K, or such other similar form as may be designated by the Commission, and to furnish to the Agents from time to time during the Term such other information as any Agent may reasonably request regarding the Company or its subsidiaries, in each case as soon as such reports, communications, documents or information becomes available or promptly upon the request of such Agent, as applicable; provided, however, that the Company shall have no obligation to provide any Agent with any document filed on EDGAR or included on the Company’s Internet website.

(h) If, at any time during the Term, any event shall occur or condition shall exist as a result of which it is necessary in the reasonable opinion of counsel for any Agent or counsel for the Company, to further amend or supplement the Prospectus or any Permitted Free Writing Prospectus as then amended or supplemented in order that the Prospectus or any such Permitted Free Writing Prospectus will not include an untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary in order to make the statements therein not misleading, in light of the circumstances existing at the time the Prospectus or any such Permitted Free Writing Prospectus is delivered to a purchaser, or if it shall be necessary, in the reasonable opinion of either such counsel, to amend or supplement the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus in order to comply with the requirements of the Act, in the case of such a determination by counsel to the Company, prompt notice shall be given, and confirmed in writing, to each Agent to cease the solicitation of offers to purchase the Shares in such Agent’s capacity as agent, and, in either case, the Company will, subject to Section 4(a) above, promptly prepare and file with the Commission such amendment or supplement, whether by filing documents pursuant to the Act, the Exchange Act or otherwise, as may be necessary to correct such untrue statement or omission or to make the Registration Statement, the Prospectus or any such Permitted Free Writing Prospectus comply with such requirements.

(i) To generally make available to its security holders as soon as reasonably practicable, but not later than 16 months after the first day of each fiscal quarter referred to below, an earnings statement (in form complying with the provisions of Section 11(a) under the Act and Rule 158 of the Commission promulgated thereunder) covering each twelve-month period beginning, in each case, not later than the first day of the Company’s fiscal quarter next following each “effective date” (as defined in such Rule 158) of the Registration Statement with respect to each sale of Shares.

(j) To apply the net proceeds from the sale of the Shares in the manner described in the Prospectus Supplement under the caption “Use of Proceeds.”

(k) Not to, and to cause its subsidiaries not to, take, directly or indirectly, any action designed to cause or result in, or that constitutes or might reasonably be expected to constitute, the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Shares; provided that nothing herein shall prevent the Company from filing or submitting reports under the Exchange Act or issuing press releases in the ordinary course of business.

(l) Except as otherwise agreed between the Company and the Agents, to pay all costs, expenses, fees and taxes in connection with (i) the preparation and filing of the Registration Statement, the Prospectus, any Permitted Free Writing Prospectus, and any amendments or supplements thereto, and the printing and furnishing of copies of each thereof to the applicable Agent and to dealers (including costs of mailing and shipment), (ii) the registration, issue and delivery of the Shares, (iii) the qualification of the Shares for offering and sale under the securities or blue sky laws of such states or other jurisdictions as any Agent may reasonably designate as aforesaid (including filing fees and the reasonable legal fees and disbursements of counsel to such Agent in connection therewith) and the printing and furnishing of copies of any blue sky surveys to such Agent, (iv) the listing of the Shares on the Exchange

and any registration thereof under the Exchange Act, (v) any filing for review, and any review, of the public offering of the Shares by FINRA (including filing fees and the reasonable legal fees and disbursements of counsel to the Agents in connection therewith), (vi) the fees and disbursements of counsel to the Company and of the Company’s independent registered public accounting firm, (vii) the performance of the Company’s other obligations hereunder and under any Terms Agreement and (viii) the documented out-of-pocket expenses of the Agents, including the reasonable fees and disbursements of counsel to the Agents in connection with this Agreement and ongoing services in connection with the transactions contemplated hereunder; provided , however , that the amount payable by the Company pursuant to clauses (iii), (v) and (viii) of this Section 4(l) shall not exceed $60,000 in the aggregate in connection with the execution of this Agreement.

(m) With respect to the offering(s) contemplated by this Agreement or any Terms Agreement, the Company will not offer shares of Common Stock or any securities convertible into or exchangeable or exercisable for shares of the Common Stock in a manner in violation of the Act or the Exchange Act; and the Company will not distribute any offering material in connection with the offer and sale of the Shares, other than the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus and any amendments or supplements thereto.

(n) Unless the Company has given written notice to each Agent that the Company has suspended activity under this Agreement and there are no pending Agency Transactions or Principal Transactions, the Company will not, without (A) giving the Agents at least three Exchange Business Days’ prior written notice specifying the nature of the proposed sale and the date of such proposed sale and (B) the Agents suspending activity under this program for such period of time as requested by the Company or deemed appropriate by the Agents in light of the proposed sale, (i) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or other equity securities of the Company or any securities convertible into or exercisable, redeemable or exchangeable for Common Stock or other equity securities of the Company, or submit to, or file with, the Commission any registration statement under the Act with respect to any of the foregoing (other than a registration statement on Form S-8 or post-effective amendment to the Registration Statement), or publicly announce the intention to undertake any of the foregoing, or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of Common Stock or other equity securities of the Company, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of shares of Common Stock or other securities, in cash or otherwise. The foregoing sentence shall not apply to (A) Shares offered and sold under this Agreement or any Terms Agreement or (B) securities issued pursuant to any of the Company’s equity incentive plans described in the Registration Statement and the Prospectus or upon the exercise of equity awards granted thereunder. Any lock-up provisions relating to a Principal Transaction shall be set forth in the applicable Terms Agreement.

(o) The Company will, pursuant to reasonable procedures developed in good faith, retain copies of each Permitted Free Writing Prospectus that is not filed with the Commission in accordance with Rule 433 under the Act.

(p) The Company will use commercially reasonable efforts to cause the Shares to be listed on the Exchange.

(q) The Company consents to each Agent trading in the Common Stock for such Agent’s own account and for the account of its clients at the same time as sales of the Shares occur pursuant to this Agreement or any Terms Agreement.

(r) If immediately prior to the third anniversary (the “ Renewal Deadline ”) of the initial effective date of the Registration Statement, the aggregate Gross Sales Price of Shares sold by the Company is less than the Maximum Amount and this Agreement has not expired or been terminated, the Company will, prior to the Renewal Deadline, file, if it has not already done so and is eligible to do so, a new shelf registration statement relating to the Shares, in a form satisfactory to the Agents, and will use its best efforts to cause such registration statement to be declared effective within 60 days after the Renewal Deadline. The Company will take all other action necessary or appropriate to permit the issuance and sale of the Shares to continue as contemplated in the expired registration statement relating to the Shares. References herein to the Registration Statement shall include such new shelf registration statement.

5. Commencement Date . The Agents’ obligations under this Agreement shall be subject to the satisfaction of the following conditions in connection with and on or prior to the date the first Transaction Proposal is delivered or first Terms Agreement is executed (the “ Commencement Date ”):

(a) the Company shall have delivered to the Agents:

(i) an officers’ certificate signed by two officers of the Company (one of whom shall be the Chief Financial Officer or other senior financial officer) certifying as to the matters set forth in Exhibit B hereto;

(ii) an opinion and a negative assurance letter of Goodwin Procter LLP, counsel for the Company, in form and substance reasonably satisfactory to the Agents, and opinions of each of McCarter & English, LLP, Lando & Anastasi, LLP and Fish & Richardson P.C., intellectual property counsels for the Company, in each case, in form and substance reasonably satisfactory to the Agents;

(iii) a “comfort” letter from PricewaterhouseCoopers LLP, addressed to the Agents and dated the date of the Commencement Date, addressing such matters as the Agents may reasonably request;

(iv) evidence reasonably satisfactory to the Agents and their counsel that the Shares have been approved for listing on the Exchange, subject only to notice of issuance on or before the date hereof;

(v) resolutions duly adopted by the Company’s board of directors or a duly appointed committee thereof, and certified by an officer of the Company, authorizing the Company’s execution of this Agreement and the

consummation by the Company of the transactions contemplated hereby, including the issuance and sale of the Shares; and

(vi) such other documents as any Agent shall reasonably request; and

(b) The Agents shall have received a letter or letters, which shall include legal opinions and negative assurance statements, of Latham & Watkins LLP, counsel to the Agents, addressed to the Agents and dated the date of the Commencement Date, addressing such matters as the Agents may reasonably request.

6. Additional Covenants of the Company . The Company further covenants and agrees with the Agents as follows:

(a) Each Transaction Proposal made by the Company that is accepted by any Agent by means of a Transaction Acceptance and each execution and delivery by the Company of a Terms Agreement shall be deemed to be (i) an affirmation that the representations, warranties and agreements of the Company herein contained and contained in any certificate delivered to the Agents pursuant hereto are true and correct at such Time of Acceptance or the date of such Terms Agreement, as the case may be, and (ii) an undertaking that such representations, warranties and agreements will be true and correct on any applicable Time of Sale and Settlement Date, as though made at and as of each such time (it being understood that such representations, warranties and agreements shall relate to the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus as amended and supplemented to the time of such Transaction Acceptance or Terms Agreement, as the case may be).

(b) Each time after the Commencement Date that (i) the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus shall be amended or supplemented (including, except as noted in the provisos at the end of this sentence, by the filing of any Incorporated Document), (ii) there is a Principal Settlement Date pursuant to a Terms Agreement, or (iii) the Agents shall reasonably request (each date referred to clauses (i), (ii) and (iii) above, a “ Bring-Down Delivery Date ”), the Company shall, unless the Agents agree otherwise, furnish or cause to be furnished to the Agents a certificate, dated as of such Bring-Down Delivery Date and delivered within one Exchange Business Day after the applicable Bring-Down Delivery Date or, in the case of a Bring-Down Delivery Date resulting from a Principal Settlement Date, delivered on such Principal Settlement Date, of the same tenor as the certificate referred to in Section 5(a)(i) hereof, modified as necessary to relate to the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus as amended and supplemented to the time of delivery of such certificates, or, in lieu of such certificates, certificates to the effect that the statements contained in the certificates referred to in Sections 5(a)(i) hereof furnished to Agents are true and correct as of such Bring-Down Delivery Date as though made at and as of such date (except that such statements shall be deemed to relate to the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus as amended and supplemented to the time of delivery of such certificate); provided , however , that the filing of a Current Report on Form 8-K will not constitute a Bring-Down Delivery Date under clause (i) above unless either (A) (x) such Current Report on Form 8-K is filed at any time during which either a Transaction Acceptance is binding and the Company has not suspended the use thereof (and prior to the settlement of the Shares specified therein) or a prospectus relating to the Shares

is required to be delivered under the Act (whether physically or through compliance with Rule 172 under the Act or any similar rule) or such Current Report on Form 8-K is filed at any time from and including the date of a Terms Agreement through and including the related Settlement Date and (y) the Agents have reasonably requested that such date be deemed to be a Bring-Down Delivery Date based upon the event or events reported in such Current Report on Form 8-K or (B) such Current Report on Form 8-K contains capsule financial information, historical or pro forma financial statements, supporting schedules or other financial data, including any Current Report on Form 8-K or part thereof under Item 2.02 of Regulation S-K of the Commission that is considered “filed” under the Exchange Act; and provided, further, that an amendment or supplement to the Registration Statement or the Prospectus relating to the offering of other securities pursuant to the Registration Statement will not constitute a Bring-Down Delivery Date. The requirement to provide a certificate under this Section 6(b) shall be waived for any Bring-Down Delivery Date occurring at a time at which no Agency Transactions or Principal Transactions are pending, which waiver shall continue until the earlier to occur of the date the Company delivers a Transaction Proposal or executes a Terms Agreement hereunder (which shall be deemed a Bring-Down Delivery Date) and the next occurring Bring-Down Delivery Date; provided , however , that such waiver shall not apply for any Bring-Down Delivery Date on which the Company files its annual report on Form 10-K. Notwithstanding the foregoing, if the Company subsequently decides to sell Shares following a Bring-Down Delivery Date when the Company relied on such waiver and did not provide the Agents with a certificate under this Section 6(b) , then before the Company delivers the Transaction Proposal or executes a Terms Agreement or any Agent sells any Shares, the Company shall provide the Agents with such certificate, dated the date such Transaction Proposal is delivered or Terms Agreement is executed.

(c) Each Bring-Down Delivery Date with respect to which the Company is obligated to deliver a certificate pursuant to Section 6(b) for which no waiver is applicable, the Company shall, unless the Agents agree otherwise, cause to be furnished to the Agents (A) the written opinion and negative assurance letter of Goodwin Procter LLP, counsel to the Company, (B) the written opinions of each of McCarter & English, LLP, Lando & Anastasi, LLP and Fish & Richardson P.C., intellectual property counsels for the Company, provided , that the written opinions of this clause (B) shall only be required to be furnished on each Bring-Down Delivery Date (x) on which the Company files its annual report on Form 10-K and (y) resulting from a Principal Settlement Date, and (C) the written opinion and negative assurance letter of Latham & Watkins LLP, counsel to the Agents, in the case of each of (A), (B) and (C) above, dated as of the applicable Bring-Down Delivery Date and delivered within one Exchange Business Day after the applicable Bring-Down Delivery Date or, in the case of a Bring-Down Delivery Date resulting from a Principal Settlement Date, dated and delivered on such Principal Settlement Date, of the same tenor as the opinions and letters referred to in Section 5(a)(ii) or Section 5(b) hereof, as applicable, but modified as necessary to relate to the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus as amended and supplemented to the time of delivery of such opinions and letters, or, in lieu of such opinions and letters, each such counsel shall furnish the Agents with a letter substantially to the effect that the Agents may rely on the opinion and letter of such counsel referred to in Section 5(a)(ii) or Section 5(b), as applicable, furnished to the Agents, to the same extent as though they were dated the date of such letter authorizing reliance (except that statements in such last opinion and letter of such counsel shall be deemed to relate to the Registration Statement, the Prospectus or any Permitted Free Writing

Prospectus as amended and supplemented to the time of delivery of such letters authorizing reliance).

(d) Each Bring-Down Delivery Date with respect to which the Company is obligated to deliver a certificate pursuant to Section 6(b) for which no waiver is applicable, the Company shall, unless the Agents agree otherwise, cause PricewaterhouseCoopers LLP to furnish to the Agents a “comfort” letter, dated as of the applicable Bring-Down Delivery Date and delivered within one Exchange Business Day after the applicable Bring-Down Delivery Date or, in the case of a Bring-Down Delivery Date resulting from a Principal Settlement Date, delivered on such Principal Settlement Date, of the same tenor as the letter referred to in Section 5(a)(iii) hereof, but modified to relate to the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus as amended and supplemented to the date of such letter, and, if the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus shall include or incorporate by reference the financial statements of any entity or business (other than the consolidated financial statements of the Company and its subsidiaries), the Company shall, if requested by the Agents, cause a firm of independent public accountants to furnish to the Agents a “comfort” letter, dated as of the applicable Bring-Down Delivery Date and delivered within one Exchange Business Day after the applicable Bring-Down Delivery Date or, in the case of a Bring-Down Delivery Date resulting from a Principal Settlement Date, delivered on such Principal Settlement Date, addressing such matters as the Agents may reasonably request .

(e) (i) No order suspending the effectiveness of the Registration Statement shall be in effect, and no proceeding for such purpose or pursuant to Section 8A under the Act shall be pending before or threatened by the Commission; the Prospectus and each Permitted Free Writing Prospectus shall have been timely filed with the Commission under the Act (in the case of a Permitted Free Writing Prospectus, to the extent required by Rule 433 under the Act); and all requests by the Commission for additional information shall have been complied with to the satisfaction of the Agents and no suspension of the qualification of the Shares for offering or sale in any jurisdiction, or of the initiation or threatening of any proceedings for any of such purposes, shall have occurred and be in effect at the time the Company delivers a Transaction Proposal to any Agent or the time any Agent delivers a Transaction Acceptance to the Company; and (ii) the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus shall not contain an untrue statement of material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading at the time the Company delivers a Transaction Proposal to any Agent or the time any Agent delivers a Transaction Acceptance to the Company.

(f) The Company shall reasonably cooperate with any reasonable due diligence review requested by the Agents or their counsel from time to time in connection with the transactions contemplated hereby or any Terms Agreement, including, without limitation, (i) at the commencement of each intended Purchase Date and any Time of Sale or Settlement Date, providing information and making available appropriate documents and appropriate corporate officers of the Company and, upon reasonable request, representatives of PricewaterhouseCoopers LLP (and, if the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus shall include or incorporate by reference the financial statements of any entity or business (other than the consolidated financial statements of the Company and its subsidiaries), representatives of the independent public accountants that audited

or reviewed such financial statements) for an update on diligence matters with representatives of the Agents and (ii) at each Bring-Down Delivery Date with respect to which the Company is obligated to deliver a certificate pursuant to Section 6(b) for which no waiver is applicable and otherwise as the Agents may reasonably request, providing information and making available documents and appropriate corporate officers of the Company and representatives of PricewaterhouseCoopers LLP (and, if the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus shall include or incorporate by reference the financial statements of any entity or business (other than the consolidated financial statements of the Company and its subsidiaries), representatives of the independent public accountants that audited or reviewed such financial statements) for one or more due diligence sessions with representatives of the Agents and their counsel.

(g) The Company shall disclose, in its quarterly reports on Form 10-Q and in its annual report on Form 10-K and, if reasonably requested by the Agents, in supplements to the Prospectus to be filed by the Company with the Commission from time to time, the number of the Shares sold through the Agents under this Agreement and any Terms Agreement, and the gross and net proceeds to the Company from the sale of the Shares and the compensation paid by the Company with respect to sales of the Shares pursuant to this Agreement during the relevant quarter or, in the case of any such prospectus supplement, such shorter period as the Agents may reasonably request or, in the case of an Annual Report on Form 10-K, during the fiscal year covered by such Annual Report and the fourth quarter of such fiscal year.

All opinions, letters and other documents referred to in Sections 6(b) through (d) above shall be reasonably satisfactory in form and substance to the Agents. The Agents will provide the Company with such notice (which may be oral, and in such case, will be confirmed via e-mail as soon as reasonably practicable thereafter) as is reasonably practicable under the circumstances when requesting an opinion, letter or other document referred to in Sections 6(b) through (d) above.

7. Conditions of the Agents’ Obligation . The Agents’ obligation to solicit purchases on an agency basis for the Shares or otherwise take any action pursuant to a Transaction Acceptance and to purchase the Shares pursuant to any Terms Agreement shall be subject to the satisfaction of the following conditions:

(a) At the Time of Acceptance, at the time of the commencement of trading on the Exchange on the Purchase Date(s) and at the relevant Time of Sale and Agency Settlement Date, or with respect to a Principal Transaction pursuant to a Terms Agreement, at the time of execution and delivery of the Terms Agreement by the Company and at the relevant Time of Sale and Principal Settlement Date:

(i) The representations, warranties and agreements on the part of the Company herein contained or contained in any certificate of an officer or officers, general partner, managing member or other authorized representative of the Company or any subsidiary of the Company delivered pursuant to the provisions hereof shall be true and correct in all respects.

(ii) The Company shall have performed and observed its covenants and other obligations hereunder and/or under any Terms Agreement, as the case may be, in all material respects.

(iii) In the case of an Agency Transaction, from the Time of Acceptance until the Agency Settlement Date, or, in the case of a Principal Transaction pursuant to a Terms Agreement, from the time of execution and delivery of the Terms Agreement by the Company until the Principal Settlement Date, trading in the Common Stock on the Exchange shall not have been suspended.

(iv) From the date of this Agreement, no event or condition of a type described in Section 3(e) hereof shall have occurred or shall exist, which event or condition is not described in a Permitted Free Writing Prospectus (excluding any amendment or supplement thereto) or the Prospectus (excluding any amendment or supplement thereto) and the effect of which in the judgment of the applicable Agent makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Shares on the applicable Settlement Date on the terms and in the manner contemplated by this Agreement, any Terms Agreement, any Permitted Free Writing Prospectus and the Prospectus.

(v) Subsequent to the relevant Time of Acceptance or, in the case of a Principal Transaction, subsequent to execution of the applicable Terms Agreement, (A) no downgrading shall have occurred in the rating accorded any debt securities or preferred equity securities of or guaranteed by the Company or any of its subsidiaries by any “nationally recognized statistical rating organization”, as such term is defined by the Commission for purposes of Section 3(a)(62) of the Exchange Act and (B) no such organization shall have publicly announced that it has under surveillance or review, or has changed its outlook with respect to, its rating of any debt securities or preferred equity securities of or guaranteed by the Company or any of its subsidiaries (other than an announcement with positive implications of a possible upgrading) in each case that has not been described in any Permitted Free Writing Prospectus issued prior to any related Time of Sale.

(vi) The Shares to be issued pursuant to the Transaction Acceptance or pursuant to a Terms Agreement, as applicable, shall have been approved for listing on the Exchange, subject only to notice of issuance.

(vii) (A) No action shall have been taken and no statute, rule, regulation or order shall have been enacted, adopted or issued by any federal, state or foreign governmental or regulatory authority that would, as of the relevant Settlement Date, prevent the issuance or sale of the Shares and (B) no injunction or order of any federal, state or foreign court shall have been

issued that would, as of the relevant Settlement Date, prevent the issuance or sale of the Shares.

(viii) (A) No order suspending the effectiveness of the Registration Statement shall be in effect and no proceeding for such purpose or pursuant to Section 8A of the Act shall be pending before or threatened by the Commission; (B) the Prospectus and each Permitted Free Writing Prospectus shall have been timely filed with the Commission under the Act (in the case of any Permitted Free Writing Prospectus, to the extent required by Rule 433 under the Act); (C) all requests by the Commission for additional information shall have been complied with to the satisfaction of the Agents; and (D) no suspension of the qualification of the Shares for offering or sale in any jurisdiction, and no initiation or threatening of any proceedings for any of such purposes, shall have occurred and be in effect. The Registration Statement, the Prospectus or any Permitted Free Writing Prospectus shall not contain an untrue statement of material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading at the time any Agent delivers a Transaction Acceptance to the Company or the Company and any Agent execute a Terms Agreement, as the case may be.

(ix) No amendment or supplement to the Registration Statement, the Prospectus or any Permitted Free Writing Prospectus shall have been filed to which any Agent shall have reasonably objected in writing.

(b) Within one Exchange Business Day after the applicable Bring-Down Delivery Date or, in the case of a Bring-Down Delivery Date resulting from a Principal Settlement Date, on such Principal Settlement Date, the Agents shall have received the officer’s certificates, opinions and negative assurance letters of counsel and “comfort” letters and other documents provided for under Sections 6(b) through (d), inclusive. For purposes of clarity and without limitation to any other provision of this Section 7 or elsewhere in this Agreement, the parties hereto agree that the Agents’ obligations, if any, to solicit purchases of Shares on an agency basis or otherwise take any action pursuant to a Transaction Acceptance shall, unless otherwise agreed in writing by the applicable Agent, be suspended during the period from and including a Bring-Down Delivery Date through and including the time that such Agent shall have received the documents described in the preceding sentence.

8. Termination .

(a) (i) The Company may terminate this Agreement in its sole discretion at any time upon prior written notice to the Agents. Any such termination shall be without liability of any party to any other party, except that (A) with respect to any pending sale, the obligations of the Company, including in respect of compensation of any applicable Agent, shall remain in full force and effect notwithstanding such termination; and (B) the provisions of Sections 3, 4 (except that if no Shares have been previously sold

hereunder or under any Terms Agreement, only Section 4(l)), 9, 13, 14 and 16 of this Agreement shall remain in full force and effect notwithstanding such termination.

(ii) In the case of any sale by the Company pursuant to a Terms Agreement, the obligations of the Company pursuant to such Terms Agreement and this Agreement may not be terminated by the Company without the prior written consent of the applicable Agent.

(b) (i) Each Agent may terminate this Agreement with respect to itself in its sole discretion at any time upon giving prior written notice to the Company (it being understood that this Agreement will remain in full force and effect with respect to each Agent that has not so terminated this Agreement with respect to itself). Any such termination shall be without liability of any party to any other party, except that the provisions of Sections 3, 4 (except that if no Shares have been previously sold hereunder or under any Terms Agreement, only Section 4(l)), 9, 13, 14 and 16 of this Agreement shall remain in full force and effect notwithstanding such termination.

(ii) In the case of any purchase by an Agent pursuant to a Terms Agreement, the obligations of such Agent pursuant to such Terms Agreement shall be subject to termination by such Agent at any time prior to or at the Principal Settlement Date if (A) since the time of execution of the Terms Agreement or the respective dates as of which information is given in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus, (i) trading generally shall have been suspended or materially limited on or by any of the New York Stock Exchange, the Nasdaq Stock Market, the Chicago Board Options Exchange, the Chicago Mercantile Exchange or the Chicago Board of Trade; (ii) trading of any securities issued or guaranteed by the Company or any of its subsidiaries shall have been suspended on any exchange or in any over-the-counter market, (iii) a general moratorium on commercial banking activities shall have been declared by federal or New York state authorities, (iv) there shall have occurred any outbreak or escalation of hostilities or any change in financial markets or any calamity or crisis, either within or outside the United States, that, solely in the case of events and conditions described in this clause (iv), in such Agent’s judgment, is material and adverse and makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Shares on the terms and in the manner contemplated in the Prospectus or such Terms Agreement. If such Agent elects to terminate its obligations pursuant to this Section 8(b)(ii), the Company shall be notified promptly in writing.

(c) This Agreement shall remain in full force and effect until the earliest of (A) termination of the Agreement pursuant to Section 8(a) or 8(b) above or otherwise by mutual written agreement of the parties, (B) such date that the Maximum Amount of Shares has been sold in accordance with the terms of this Agreement and any Terms Agreements and (C) the third anniversary of the initial effective date of the Registration Statement, in each case except

that the provisions of Section 3, 4 (except that if no Shares have been previously sold hereunder or under any Terms Agreement, only Section 4(l)), 9, 13, 14 and 16 of this Agreement shall remain in full force and effect notwithstanding such termination.

(d) Any termination of this Agreement shall be effective on the date specified in such notice of termination; provided that, notwithstanding the foregoing, such termination shall not be effective until the close of business on the date of receipt of such notice by the Agents or the Company, as the case may be, or such later date as may be required pursuant to Section 8(a) or (b). If such termination shall occur prior to the Settlement Date for any sale of Shares, such sale shall settle in accordance with the provisions of Section 2 hereof.

9. Indemnity and Contribution .

(a) The Company agrees to indemnify and hold harmless each Agent, its affiliates, directors and officers and each person, if any, who controls such Agent within the meaning of Section 15 of the Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, reasonable out of pocket legal fees and other expenses incurred in connection with any suit, action or proceeding or any claim asserted, as such fees and expenses are incurred), that arise out of, or are based upon, (i) any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement (or any amendment thereto) or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary in order to make the statements therein, not misleading or (ii) any untrue statement or alleged untrue statement of a material fact contained in the Prospectus (or any amendment or supplement thereto), any Permitted Free Writing Prospectus (or any amendment or supplement thereto), any “issuer information” filed or required to be filed pursuant to Rule 433(d) under the Act or any road show as defined in Rule 433(h) under the Act (a “ road show ”), or caused by any omission or alleged omission to state therein a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading, in each case except insofar as such losses, claims, damages or liabilities arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to the Agents furnished to the Company in writing by the Agents expressly for use therein, it being understood and agreed that the only such information furnished by the Agents consists of the information described as such in subsection (b) below.

(b) Each Agent agrees, severally and not jointly, to indemnify and hold harmless the Company, its directors, its officers who signed the Registration Statement and each person, if any, who controls the Company within the meaning of Section 15 of the Act or Section 20 of the Exchange Act to the same extent as the indemnity set forth in paragraph (a) above, but only with respect to any losses, claims, damages or liabilities that arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to the Agents furnished to the Company in writing by the Agents expressly for use in the Registration Statement (or any amendment thereto), the Prospectus (or any amendment or supplement thereto), any Permitted Free Writing Prospectus (or any amendment or supplement thereto) or any road show, it being understood and agreed upon that such information shall consist solely of the following: the information appearing in the

third sentence of the second paragraph and the first and second sentences of the fourth paragraph under the caption “Plan of Distribution” in the Prospectus Supplement.

(c) If any suit, action, proceeding (including any governmental or regulatory investigation), claim or demand shall be brought or asserted against any person in respect of which indemnification may be sought pursuant to either Section 9(a) or 9(b) above, such person (the “ Indemnified Person ”) shall promptly notify the person against whom such indemnification may be sought (the “ Indemnifying Person ”) in writing; provided that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have under this Section 9 except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; and provided , further , that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have to an Indemnified Person otherwise than under this Section 9. If any such proceeding shall be brought or asserted against an Indemnified Person and it shall have notified the Indemnifying Person thereof, the Indemnifying Person shall retain counsel reasonably satisfactory to the Indemnified Person (who shall not, without the consent of the Indemnified Person, be counsel to the Indemnifying Person) to represent the Indemnified Person and any others entitled to indemnification pursuant to this Section 9 that the Indemnifying Person may designate in such proceeding and shall pay the fees and expenses of such counsel related to such proceeding, as incurred. In any such proceeding, any Indemnified Person shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Indemnified Person unless (i) the Indemnifying Person and the Indemnified Person shall have mutually agreed to the contrary; (ii) the Indemnifying Person has failed within a reasonable time to retain counsel reasonably satisfactory to the Indemnified Person; (iii) the Indemnified Person shall have reasonably concluded that there may be legal defenses available to it that are different from or in addition to those available to the Indemnifying Person; or (iv) the named parties in any such proceeding (including any impleaded parties) included both the Indemnifying Person and the Indemnified Person and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them. It is understood and agreed that the Indemnifying Person shall not, in connection with any proceeding or related proceeding in the same jurisdiction, be liable for the reasonable fees and expenses of more than one separate firm (in addition to any local counsel) for (A) the Agents and their affiliates, directors and officers and their control persons, if any, or (B) the Company, its directors, its officers who signed the Registration Statement and its control persons, if any, as the case may be, and that all such reasonable fees and expenses shall be paid or reimbursed as they are incurred. Any such separate firm for the Agents and their affiliates, directors and officers and their control persons, if any, shall be designated in writing by the Agents, and any such separate firm for the Company, its directors, its officers who signed the Registration Statement and its control persons, if any, shall be designated in writing by the Company. The Indemnifying Person shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the Indemnifying Person agrees to indemnify each Indemnified Person from and against any loss or liability by reason of such settlement or judgment. No Indemnifying Person shall, without the written consent of the Indemnified Person, effect any settlement of any pending or threatened proceeding in respect of which any Indemnified Person is or could have been a party and indemnification is or could have been sought hereunder by such Indemnified Person, unless such settlement (x) includes an unconditional release of such Indemnified Person, in form and substance reasonably satisfactory

to such Indemnified Person, from all liability on claims that are the subject matter of such proceeding and (y) does not include any statement as to or any admission of fault, culpability or a failure to act by or on behalf of any Indemnified Person. Notwithstanding the foregoing sentence, if at any time an Indemnified Person shall have requested an Indemnifying Person to reimburse the Indemnified Person for fees and expenses of counsel as contemplated by this Section 9(c), the Indemnifying Person agrees that it shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 30 days after receipt by such Indemnifying Person of the aforesaid request and (ii) such Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement.

(d) If the indemnification provided for in Sections 9(a) and 9(b) above is unavailable to an Indemnified Person or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then each Indemnifying Person under such Sections, in lieu of indemnifying such Indemnified Person thereunder, shall contribute to the amount paid or payable by such Indemnified Person as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company, on the one hand, and the applicable Agents, on the other, from the offering of the Shares pursuant to this Agreement and any Terms Agreements or (ii) if the allocation provided by clause (i) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) but also the relative fault of the Company, on the one hand, and the applicable Agents, on the other, in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company, on the one hand, and the applicable Agents, on the other, shall be deemed to be in the same respective proportions as the net proceeds (before deducting expenses) received by the Company from the sale of the Shares pursuant to this Agreement and any Terms Agreements and the total discounts and commissions received by the applicable Agent in connection therewith bear to the aggregate Gross Sales Price of such Shares. The relative fault of the Company, on the one hand, and applicable Agents, on the other, shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company, on the one hand, or by applicable Agents, on the other hand, and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

(e) The Company and the Agents agree that it would not be just and equitable if contribution pursuant to this Section 9 were determined by pro rata allocation or by any other method of allocation that does not take account of the equitable considerations referred to in Section 9(d) above. The amount paid or payable by an Indemnified Person as a result of the losses, claims, damages and liabilities referred to in Section 9(d) above shall be deemed to include, subject to the limitations set forth above, any legal or other expenses incurred by such Indemnified Person in connection with any such action or claim. Notwithstanding the provisions of this Section 9, in no event shall an Agent be required to contribute any amount in excess of the amount by which the total discounts and commissions received by such Agent with respect to the offering of the Shares pursuant to this Agreement and any Terms Agreements exceeds the amount of any damages that such Agent has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of

fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation.

(f) The remedies provided for in this Section 9 are not exclusive and shall not limit any rights or remedies which may otherwise be available to any Indemnified Person at law or in equity.

10. Notices . All notices and other communications under this Agreement and any Terms Agreement shall be in writing and shall be deemed to have been duly given if mailed or transmitted and confirmed by any standard form of communication, and, if to the Agents, shall be sufficient in all respects if delivered or sent to J.P. Morgan Securities LLC, 383 Madison Avenue, 7 th Floor, New York, New York 10179, to the attention of Special Equities Group, Jefferies LLC, 520 Madison Avenue, New York, New York 10022, Attention: General Counsel; and SVB Leerink LLC, One Federal Street, 37th Floor, Boston, Massachusetts 02110, Attention: John I. Fitzgerald, Esq.; with a copy to Peter N. Handrinos, Latham & Watkins LLP, 200 Clarendon Street, Boston, Massachusetts 02116, and, if to the Company, shall be sufficient in all respects if delivered or sent to it at Rubius Therapeutics, Inc., 325 Vassar Street, Suite 1A, Cambridge, MA 02139 ; Attention: Pablo J. Cagnoni; with a copy to Stuart Cable, Goodwin Procter LLP, 100 Northern Avenue, Boston, Massachusetts 02210. Notwithstanding the foregoing, Transaction Proposals shall be delivered by the Company to the applicable Agent by telephone or email to any of the applicable individuals listed as authorized representatives of such applicable Agent on Schedule B hereto; and Transaction Acceptances shall be delivered by the applicable Agent to the Company by email to Andrew Oh (email andrew.oh@rubiustx.com) and Joanne Protano (email joanne.protano@rubiustx.com).

11. No Fiduciary Relationship . The Company acknowledges and agrees that each Agent is acting solely in the capacity of an arm’s length contractual counterparty to the Company with respect to the offering of Shares contemplated hereby and any Terms Agreements (including in connection with determining the terms of the offering) and not as a financial advisor or a fiduciary to, or an agent of, the Company or any other person. Additionally, none of Agent is advising the Company or any other person as to any legal, tax, investment, accounting or regulatory matters in any jurisdiction. The Company shall consult with its own advisors concerning such matters and shall be responsible for making its own independent investigation and appraisal of the transactions contemplated hereby, and no Agent shall have any responsibility or liability to the Company with respect thereto. Any review by the Agents of the Company, the transactions contemplated hereby or other matters relating to such transactions will be performed solely for the benefit of the Agents and shall not be on behalf of the Company.

12. Adjustments for Stock Splits . The parties acknowledge and agree that all share related numbers contained in this Agreement, any Transaction Proposal and any Transaction Acceptance shall be adjusted to take into account any stock split effected with respect to the Shares.

13. Miscellaneous .

(a) Governing Law . This Agreement, any Terms Agreement and any claim, controversy or dispute arising under or relating to this Agreement or any Terms Agreement shall be governed by, and construed in accordance with, the laws of the State of New York.

(b) Submission to Jurisdiction . The Company hereby submits to the exclusive jurisdiction of the U.S. federal and New York state courts in the Borough of Manhattan in The City of New York in any suit or proceeding arising out of or relating to this Agreement or the transactions contemplated hereby. The Company waives any objection which it may now or hereafter have to the laying of venue of any such suit or proceeding in such courts. The Company agrees that final judgment in any such suit, action or proceeding brought in such court shall be conclusive and binding upon the Company and may be enforced in any court to the jurisdiction of which Company is subject by a suit upon such judgment.

(c) Waiver of Jury Trial. Each of the parties hereto hereby waives any right to trial by jury in any suit or proceeding arising out of or relating to this Agreement and any Terms Agreement.

14. Persons Entitled to Benefit of Agreement . This Agreement and any Terms Agreement shall inure to the benefit of and be binding upon the parties hereto and thereto, respectively, and their respective successors and the officers, directors, affiliates and controlling persons referred to in Section 9 hereof. Nothing in this Agreement or any Terms Agreement is intended or shall be construed to give any other person any legal or equitable right, remedy or claim under or in respect of this Agreement or any such Terms Agreement or any provision contained herein or therein. No purchaser of Shares from or through the Agents shall be deemed to be a successor merely by reason of purchase.

15. Counterparts . This Agreement and any Terms Agreement may be signed in counterparts (which may include counterparts delivered by any standard form of telecommunication), each of which shall be an original and all of which together shall constitute one and the same instrument.

16. Survival . The respective indemnities, rights of contribution, representations, warranties and agreements of the Company and the Agents contained in this Agreement or any Terms Agreement or made by or on behalf of the Company or the Agents pursuant to this Agreement or any Terms Agreement or any certificate delivered pursuant hereto or thereto shall survive the delivery of and payment for the Shares and shall remain in full force and effect, regardless of any termination of this Agreement or any Terms Agreement or any investigation made by or on behalf of the Company or the Agents.

17. Certain Defined Terms . For purposes of this Agreement, except where otherwise expressly provided, the term “affiliate” has the meaning set forth in Rule 405 under Act; the term “business day” means any day other than a day on which banks are permitted or required to be closed in New York City; and the term “subsidiary” has the meaning set forth in Rule 405 under the Act.

18. Recognition of the U.S. Special Resolution Regimes .

(a) In the event that any Agent that is a Covered Entity becomes subject to a proceeding under a U.S. Special Resolution Regime, the transfer from such Agent of this Agreement or any Terms Agreement, and any interest and obligation in or under this Agreement or any Terms Agreement, will be effective to the same extent as the transfer would be effective under the U.S. Special Resolution Regime if this Agreement or any Terms Agreement, and any

such interest and obligation, were governed by the laws of the United States or a state of the United States.

(b) In the event that any Agent that is a Covered Entity or a BHC Act Affiliate of such Agent becomes subject to a proceeding under a U.S. Special Resolution Regime, Default Rights under this Agreement or any Terms Agreement that may be exercised against such Agent are permitted to be exercised to no greater extent than such Default Rights could be exercised under the U.S. Special Resolution Regime if this Agreement or any Terms Agreement were governed by the laws of the United States or a state of the United States.

As used in this Section 18:

“BHC Act Affiliate” has the meaning assigned to the term “affiliate” in, and shall be interpreted in accordance with, 12 U.S.C. § 1841(k).

“Covered Entity” means any of the following:

(i) a “covered entity” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 252.82(b);

(ii) a “covered bank” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 47.3(b); or

(iii) a “covered FSI” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 382.2(b).

“Default Right” has the meaning assigned to that term in, and shall be interpreted in accordance with, 12 C.F.R. §§ 252.81, 47.2 or 382.1, as applicable.

“U.S. Special Resolution Regime” means each of (i) the Federal Deposit Insurance Act and the regulations promulgated thereunder and (ii) Title II of the Dodd-Frank Wall Street Reform and Consumer Protection Act and the regulations promulgated thereunder.

19. Compliance with USA Patriot Act . In accordance with the requirements of the USA Patriot Act (Title III of Pub. L. 107-56 (signed into law October 26, 2001)), each Agent is required to obtain, verify and record information that identifies its clients, including the Company, which information may include the name and address of its clients, as well as other information that will allow such Agent to properly identify its clients.

20. Amendments or Waivers . No amendment or waiver of any provision of this Agreement or any Terms Agreement, nor any consent or approval to any departure therefrom, shall in any event be effective unless the same shall be in writing and signed by the parties hereto or thereto as the case may be.

21. Headings . The headings herein and in any Terms Agreement are included for convenience of reference only and are not intended to be part of, or to affect the meaning or interpretation of, this Agreement or any Terms Agreement.

[ Signature Page Follows ]

If the foregoing correctly sets forth the understanding between the Company and each Agent, please so indicate in the space provided below for that purpose, whereupon this letter and your acceptance shall constitute a binding agreement among the Company and the Agent.

	Very truly yours,

	RUBIUS THERAPEUTICS, INC.

	By:	/s/ Andrew M. Oh
	Name:	Andrew M. Oh
	Title:	Chief Financial Officer

Accepted and agreed to as of the date first above written:

J.P. MORGAN SECURITIES LLC

By:	/s/ Brett Chalmers
Name:	Brett Chalmers
Title:	Vice President

JEFFERIES LLC

By:	/s/ Michael Magarro
	Name:		Michael Magarro
	Title:		Managing Director

SVB LEERINK LLC

By:	/s/ Stuart R. Nayman
	Name:	Stuart R. Nayman
	Title:	Managing Director

Schedule A

Authorized Company Representatives

Pablo Cagnoni

Andrew Oh

Schedule B

Authorized Agent Representatives

J.P. Morgan Securities LLC	Jefferies LLC	SVB Leerink LLC

Stephanie Little	Michael Magarro	Dan Dubin, M.D.
stephanie.y.little@jpmorgan.com	mmagarro@jefferies.com	dan.dubin@svbleerink.com
(312) 732-3229	(917) 421-1963
		Brendan Griffin
Jemil Salih	Donald Lynaugh	brendan.griffin@svbleerink.com
jemil.d.salih@jpmorgan.com	dlynaugh@jefferies.com
(212) 622-2723	(212) 421-1964	Sean Pitt
		sean.pitt@svbleerink.com
Ara Movsesian	Jack Fabbri
ara.movsesian@jpmorgan.com	JFABBRI@Jefferies.com	Rahul Chaudhary
(212) 622-2619	(212) 336-7473	rahul.chaudhary@svbleerink.com

Brett Chalmers		Patrick Morley
Brett.chalmers@jpmorgan.com		patrick.morley@svbleerink.com
(212) 622-2252
		Sam Spector
Marlee Burr		sam.spector@svbleerink.com
marlee.k.burr@jpmorgan.com
(212) 622-8784		Stuart Nayman
		stuart.nayman@svbleerink.com

		Eric Olson
		eric.olson@svbleerink.com

Exhibit A

Rubius Therapeutics, Inc. Common Stock

TERMS AGREEMENT

, 20

[J.P. Morgan Securities LLC
383 Madison Avenue

New York, New York 10179]

[Jefferies LLC
520 Madison Avenue
New York, New York 10022]

[SVB Leerink LLC
One Federal Street, 37th Floor
Boston, Massachusetts 02110]

Ladies and Gentlemen:

Rubius Therapeutics, Inc., a Delaware corporation (the “ Company ”), proposes, subject to the terms and conditions stated herein and in the Distribution Agreement dated August 1, 2019 (the “ Distribution Agreement ”) between the Company and J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC to issue and sell to · (the “ Agent ”) the securities specified in the Schedule hereto (the “ Purchased Securities ”). Unless otherwise defined below, terms defined in the Distribution Agreement shall have the same meanings when used herein.

Each of the provisions of the Distribution Agreement not specifically related to the solicitation by the Agent, as agent of the Company, of offers to purchase securities is incorporated herein by reference in its entirety, and shall be deemed to be part of this Terms Agreement to the same extent as if such provisions had been set forth in full herein. Each of the representations, warranties and agreements set forth therein shall be deemed to have been made as of the date of this Terms Agreement and the Settlement Date set forth in the Schedule hereto.

An amendment to the Registration Statement or a supplement to the Prospectus, as the case may be, relating to the Purchased Securities, in the form heretofore delivered to the Agent, is now proposed to be filed with the Securities and Exchange Commission.

Subject to the terms and conditions set forth herein and in the Distribution Agreement which are incorporated herein by reference, the Company agrees to issue and sell to the Agent, and the latter agrees to purchase from the Company, the Purchased Securities at the time and place and at the purchase price set forth in the Schedule hereto.

Notwithstanding any provision of the Distribution Agreement or this Terms Agreement to the contrary, the Company consents to the Agent trading in the Common Stock for Agent’s

own account and for the account of its clients at the same time as sales of the Purchased Securities occur pursuant to this Terms Agreement.

[Signature Page Follows]

If the foregoing is in accordance with your understanding, please sign and return to us a counterpart hereof, whereupon this Terms Agreement, including those provisions of the Distribution Agreement incorporated herein by reference, shall constitute a binding agreement between the Agent and the Company.

	RUBIUS THERAPEUTICS, INC.

	By:
		Name:
		Title:

Accepted and agreed as of the date first above written:

[NAME OF APPLICABLE AGENT]

By:
	Name:
	Title:

Schedule to Terms Agreement

Title of Purchased Securities:

Common Stock, par value $0.001 per share

Number of Shares of Purchased Securities:

[ · ] shares

Initial Price to Public:

$ [ · ] per share

Purchase Price Payable by the Agent:

$ [ · ] per share

Method of and Specified Funds for Payment of Purchase Price:

By wire transfer to a bank account specified by the Company in same day funds.

Method of Delivery:

To the Agent’s account, or the account of the Agent’s designee, at The Depository Trust Company via DWAC in return for payment of the purchase price.

Settlement Date:

[ · ] , 20 [ · ]

Closing Location:

[ · ]

Documents to be Delivered:

The following documents referred to in the Distribution Agreement shall be delivered on the Settlement Date as a condition to the closing for the Purchased Securities (which documents shall be dated on or as of the Settlement Date and shall be appropriately updated to cover any Permitted Free Writing Prospectuses and any amendments or supplements to the Registration Statement, the Prospectus, any Permitted Free Writing Prospectuses and any documents incorporated by reference therein):

(1) the officer’s certificate referred to in Section 5(a)(i);

(2) the opinions and negative assurance letters of the Company’s outside counsel referred to in Section 5(a)(ii);

(3) the “comfort” letter referred to in Section 5(a)(iii);

(4) the opinion and negative assurance letter referred to in Section 5(b); and

(5) such other documents as the Agent shall reasonably request.

[ Lockup: ]

[ · ]

Time of sale: [ · ] [ a.m./p.m. ] (New York City time) on [ · ] , [ · ]

Time of sale information:

· The number of shares of Purchased Securities set forth above

· The initial price to public set forth above

Exhibit B

OFFICERS’ CERTIFICATE

Dated , 20

We, [name], Chief Executive Offer, and [name], Chief Financial Officer, of Rubius Therapeutics, Inc., a Delaware corporation (the “ Company ”), do hereby certify that this certificate is signed by us pursuant to the Distribution Agreement dated August 1, 2019 between the Company and J.P. Morgan Securities LLC, Jefferies LLC and SVB Leerink LLC (the “ Agreement ”), and do hereby further certify on behalf of the Company, as follows:

1. The representations and warranties of the Company in the Agreement are true and correct on and as of the date hereof as though made on and as of this date;

2. The Company has performed all obligations and satisfied all conditions on its part to be performed or satisfied pursuant to the Agreement on or prior to the date hereof;

3. The Company’s Registration Statement (File No. 333- · ) and any post-effective amendments thereto have become effective under the Act; no stop order suspending the effectiveness of such Registration Statement has been issued and no proceeding for that purpose or pursuant to Section 8A of the Act has been initiated or, to the knowledge of the undersigned, threatened by the Commission; no notice of objection of the Commission to the use of such Registration Statement pursuant to Rule 401(g)(2) under the Act has been received by the Company; and all requests for additional information on the part of the Commission have been complied with; and

4. Since the respective dates as of which information is given in the Registration Statement, the Prospectus and any Permitted Free Writing Prospectus, except as otherwise stated therein, (i) there has not been any change in the capital stock (other than the issuance of shares of Common Stock upon exercise of stock options issued under, and the grant of options and awards under, equity incentive plans described in the Registration Statement and the Prospectus, the issuance of Shares pursuant to the Agreement) or short-term debt or long-term debt (except for borrowings and the repayment of borrowings in the ordinary course of business and pursuant to the Company’s loan and security agreement with Solar Capital Ltd.) of the Company or any of its subsidiaries, or any dividend or distribution of any kind declared, set aside for payment, paid or made by the Company on any class of capital stock, or any material adverse change, or any development that would reasonably be expected to result in a prospective material adverse change, in or affecting the business, properties, management, financial position, stockholders’ equity, results of operations or prospects of the Company and its subsidiaries taken as a whole; (ii) neither the Company nor any of its subsidiaries has entered into any transaction or agreement (whether or not in the ordinary course of business) that is material to the Company and its subsidiaries taken as a whole or incurred any liability or obligation, direct or contingent, that is material to the Company and its subsidiaries taken as a whole; and (iii) neither the Company nor any of its subsidiaries has sustained any loss or interference with its business that is material to

the Company and its subsidiaries taken as a whole and that is either from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor disturbance or dispute or any action, order or decree of any court or arbitrator or governmental or regulatory authority.

All capitalized terms used herein and not otherwise defined shall have the respective meanings assigned to them in the Agreement.

[ Signature Page Follows ]


	Name:
	Title: Chief Executive Officer



	Name:
	Title: Chief Financial Officer

Exhibit 4.3

RUBIUS THERAPEUTICS, INC.

Issuer

AND

[TRUSTEE],

Trustee

INDENTURE

Dated as of [ · ], 2019

Senior Debt Securities

TABLE OF CONTENTS(1)

ARTICLE 1 DEFINITIONS			1

	Section 1.01	Definitions of Terms	1

ARTICLE 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES			5

	Section 2.01	Designation and Terms of Securities	5
	Section 2.02	Form of Securities and Trustee’s Certificate	8
	Section 2.03	Denominations: Provisions for Payment	8
	Section 2.04	Execution and Authentications	10
	Section 2.05	Registration of Transfer and Exchange	11
	Section 2.06	Temporary Securities	12
	Section 2.07	Mutilated, Destroyed, Lost or Stolen Securities	12
	Section 2.08	Cancellation	13
	Section 2.09	Benefits of Indenture	13
	Section 2.10	Authenticating Agent	14
	Section 2.11	Global Securities	14

ARTICLE 3 REDEMPTION OF SECURITIES AND SINKING FUND PROVISIONS			15

	Section 3.01	Redemption	15
	Section 3.02	Notice of Redemption	15
	Section 3.03	Payment Upon Redemption	17
	Section 3.04	Sinking Fund	17
	Section 3.05	Satisfaction of Sinking Fund Payments with Securities	17
	Section 3.06	Redemption of Securities for Sinking Fund	18

ARTICLE 4 COVENANTS			18

	Section 4.01	Payment of Principal, Premium and Interest	18
	Section 4.02	Maintenance of Office or Agency	18
	Section 4.03	Paying Agents	19
	Section 4.04	Appointment to Fill Vacancy in Office of Trustee	20
	Section 4.05	Compliance with Consolidation Provisions	20

ARTICLE 5 SECURITYHOLDERS’ LISTS AND REPORTS BY THE COMPANY AND THE TRUSTEE			20

	Section 5.01	Company to Furnish Trustee Names and Addresses of Securityholders	20
	Section 5.02	Preservation Of Information; Communications With Securityholders	20
	Section 5.03	Reports by the Company	21
	Section 5.04	Reports by the Trustee	21

ARTICLE 6 REMEDIES OF THE TRUSTEE AND SECURITYHOLDERS ON EVENT OF DEFAULT			22

	Section 6.01	Events of Default	22
	Section 6.02	Collection of Indebtedness and Suits for Enforcement by Trustee	24

(1) This Table of Contents does not constitute part of the Indenture and shall not have any bearing on the interpretation of any of its terms or provisions.

	Section 6.03	Application of Moneys Collected	25
	Section 6.04	Limitation on Suits	25
	Section 6.05	Rights and Remedies Cumulative; Delay or Omission Not Waiver	26
	Section 6.06	Control by Securityholders	26
	Section 6.07	Undertaking to Pay Costs	27

ARTICLE 7 CONCERNING THE TRUSTEE			27

	Section 7.01	Certain Duties and Responsibilities of Trustee	27
	Section 7.02	Certain Rights of Trustee	29
	Section 7.03	Trustee Not Responsible for Recitals or Issuance or Securities	30
	Section 7.04	May Hold Securities	31
	Section 7.05	Moneys Held in Trust	31
	Section 7.06	Compensation and Reimbursement	31
	Section 7.07	Reliance on Officer’s Certificate or Opinion of Counsel	32
	Section 7.08	Disqualification; Conflicting Interests	32
	Section 7.09	Corporate Trustee Required; Eligibility	32
	Section 7.10	Resignation and Removal; Appointment of Successor	33
	Section 7.11	Acceptance of Appointment By Successor	34
	Section 7.12	Merger, Conversion, Consolidation or Succession to Business	35
	Section 7.13	Preferential Collection of Claims Against the Company	35
	Section 7.14	Notice of Default	35

ARTICLE 8 CONCERNING THE SECURITYHOLDERS			36

	Section 8.01	Evidence of Action by Securityholders	36
	Section 8.02	Proof of Execution by Securityholders	36
	Section 8.03	Who May be Deemed Owners	37
	Section 8.04	Certain Securities Owned by Company Disregarded	37
	Section 8.05	Actions Binding on Future Securityholders	37

ARTICLE 9 SUPPLEMENTAL INDENTURES			38

	Section 9.01	Supplemental Indentures Without the Consent of Securityholders	38
	Section 9.02	Supplemental Indentures With Consent of Securityholders	39
	Section 9.03	Effect of Supplemental Indentures	39
	Section 9.04	Securities Affected by Supplemental Indentures	39
	Section 9.05	Execution of Supplemental Indentures	40

ARTICLE 10 SUCCESSOR ENTITY			40

	Section 10.01	Company May Consolidate, Etc.	40
	Section 10.02	Successor Entity Substituted	41

ARTICLE 11 SATISFACTION AND DISCHARGE			41

	Section 11.01	Satisfaction and Discharge of Indenture	41
	Section 11.02	Discharge of Obligations	42
	Section 11.03	Deposited Moneys to be Held in Trust	42
	Section 11.04	Payment of Moneys Held by Paying Agents	43
	Section 11.05	Repayment to Company	43

ARTICLE 12 IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS AND DIRECTORS			43

	Section 12.01	No Recourse	43

ARTICLE 13 MISCELLANEOUS PROVISIONS			44

	Section 13.01	Effect on Successors and Assigns	44
	Section 13.02	Actions by Successor	44
	Section 13.03	Surrender of Company Powers	44
	Section 13.04	Notices	44
	Section 13.05	Governing Law; Jury Trial Waiver	44
	Section 13.06	Treatment of Securities as Debt	45
	Section 13.07	Certificates and Opinions as to Conditions Precedent	45
	Section 13.08	Payments on Business Days	45
	Section 13.09	Conflict with Trust Indenture Act	45
	Section 13.10	Counterparts	46
	Section 13.11	Separability	46
	Section 13.12	Compliance Certificates	46
	Section 13.13	USA PATRIOT ACT	46
	Section 13.14	Calculations	46

TRUST INDENTURE ACT CROSS-REFERENCE TABLE			A-1

iii

INDENTURE

INDENTURE , dated as of [ · ], 201 , among RUBIUS THERAPEUTICS, INC. , a Delaware corporation (the “ Company ”), and [ TRUSTEE ] as trustee (the “ Trustee ”):

WHEREAS , for its lawful corporate purposes, the Company has duly authorized the execution and delivery of this Indenture to provide for the issuance of debt securities (hereinafter referred to as the “ Securities ”), in an unlimited aggregate principal amount to be issued from time to time in one or more series as in this Indenture provided, as registered Securities without coupons, to be authenticated by the certificate of the Trustee;

WHEREAS , to provide the terms and conditions upon which the Securities are to be authenticated, issued and delivered, the Company has duly authorized the execution of this Indenture; and

WHEREAS , all things necessary to make this Indenture a valid and binding agreement of the Company, in accordance with its terms, have been done.

NOW, THEREFORE , in consideration of the premises and the purchase of the Securities by the holders thereof, it is mutually covenanted and agreed as follows for the equal and ratable benefit of the holders of Securities:

ARTICLE 1
DEFINITIONS

Section 1.01 Definitions of Terms .

The terms defined in this Section (except as in this Indenture or any indenture supplemental hereto otherwise expressly provided or unless the context otherwise requires) for all purposes of this Indenture and of any indenture supplemental hereto shall have the respective meanings specified in this Section and shall include the plural as well as the singular. All other terms used in this Indenture that are defined in the Trust Indenture Act of 1939, as amended, or that are by reference in such Act defined in the Securities Act of 1933, as amended (except as herein or any indenture supplemental hereto otherwise expressly provided or unless the context otherwise requires), shall have the meanings assigned to such terms in said Trust Indenture Act and in said Securities Act as in force at the date of the execution of this instrument.

“ Authenticating Agent ” means an authenticating agent with respect to all or any of the series of Securities appointed by the Trustee pursuant to Section 2.10 .

“ Bankruptcy Law ” means Title 11, U.S. Code, or any similar federal or state law for the relief of debtors.

“ Board of Directors ” means the Board of Directors (or the functional equivalent thereof) of the Company or any duly authorized committee of such Board.

“ Board Resolution ” means a copy of a resolution certified by the Secretary or an Assistant Secretary of the Company to have been duly adopted by the Board of Directors and to be in full force and effect on the date of such certification and delivered to the Trustee.

“ Business Day ” means, with respect to any series of Securities, any day other than a day on which federal or state banking institutions in the Borough of Manhattan, the City of New York, or at a place of payment, are authorized or obligated by law, executive order or regulation to close.

“ Commission ” means the Securities and Exchange Commission, as from time to time constituted, created under the Exchange Act, or, if at any time after the execution of this instrument such Commission is not existing and performing the duties now assigned to it under the Trust Indenture Act, then the body performing such duties at such time.

“ Company ” means Rubius Therapeutics, a corporation duly organized and existing under the laws of the State of Delaware, and, subject to the provisions of Article 10 , shall also include its successors and assigns.

“ Company Order ” means a written order of the Company, signed by an Officer of the Company, and delivered to the Trustee.

“ Corporate Trust Office ” means the office of the Trustee at which, at any particular time, its corporate trust business shall be administered, which office at the date hereof is located at .

“ Custodian ” means any receiver, trustee, assignee, liquidator or similar official under any Bankruptcy Law.

“ Defaulted Interest ” has the meaning set forth in Section 2.03 .

“ Depositary ” means, with respect to Securities of any series for which the Company shall determine that such Securities will be issued as a Global Security, The Depository Trust Company, another clearing agency, or any successor registered as a clearing agency under the Exchange Act, or other applicable statute or regulation, which, in each case, shall be designated by the Company pursuant to either Section 2.01 or 2.11 .

“ Event of Default ” means, with respect to Securities of a particular series, any event specified in Section 6.01 , continued for the period of time, if any, therein designated.

“ Exchange Act ” means the United States Securities and Exchange Act of 1934, as amended, and the rules and regulations promulgated by the Commission thereunder.

“ Global Security ” means a Security issued to evidence all or a part of any series of Securities which is executed by the Company and authenticated and delivered by the Trustee to the Depositary or pursuant to the Depositary’s instruction, all in accordance with the Indenture, which shall be registered in the name of the Depositary or its nominee.

“ Governmental Obligations ” means securities that are (a) direct obligations of the United States of America for the payment of which its full faith and credit is pledged or (b) obligations of a Person controlled or supervised by and acting as an agency or instrumentality of the United States of America, the payment of which is unconditionally guaranteed as a full faith and credit obligation by the United States of America that, in either case, are not callable or redeemable at the option of the issuer thereof at any time prior to the stated maturity of the applicable series of Securities, and shall also include a depositary receipt issued by a bank or trust company as custodian with respect to any such Governmental Obligation or a specific payment of principal of or interest on any such Governmental Obligation held by such custodian for the account of the holder of such depositary receipt; provided , however , that (except as required by law) such custodian is not authorized to make any deduction from the amount payable to the holder of such depositary receipt from any amount received by the custodian in respect of the Governmental Obligation or the specific payment of principal of or interest on the Governmental Obligation evidenced by such depositary receipt.

“ herein ”, “ hereof ” and “ hereunder ”, and other words of similar import, refer to this Indenture as a whole and not to any particular Article, Section or other subdivision.

“ Indenture ” means this instrument as originally executed or as it may from time to time be supplemented or amended by one or more indentures supplemental hereto entered into in accordance with the terms hereof and shall include the terms of particular series of Securities established as contemplated by Section 2.01 .

“ Interest Payment Date ”, when used with respect to any installment of interest on a Security of a particular series, means the date specified in such Security or in a Board Resolution or in an indenture supplemental hereto with respect to such series as the fixed date on which an installment of interest with respect to Securities of that series is due and payable.

“ Officer ” means, with respect to the Company, the Chairman of the Board of Directors, a Chief Executive Officer, a President, a Chief Financial Officer, a Chief Operating Officer, any Executive Vice President, any Senior Vice President, any Vice President, the Treasurer or any Assistant Treasurer, the Controller or any Assistant Controller or the Secretary or any Assistant Secretary.

“ Officer’s Certificate ” means a certificate signed by any Officer. Each such certificate shall include the statements provided for in Section 13.07 , if and to the extent required by the provisions thereof.

“ Opinion of Counsel ” means an opinion in writing subject to customary exceptions of legal counsel, who may be an employee of or counsel for the Company, that is delivered to the Trustee in accordance with the terms hereof. Each such opinion shall include the statements provided for in Section 13.07 , if and to the extent required by the provisions thereof.

“ Outstanding ”, when used with reference to Securities of any series, means, subject to the provisions of Section 8.04 , as of any particular time, all Securities of that series theretofore authenticated and delivered by the Trustee under this Indenture, except (a) Securities theretofore canceled by the Trustee or any paying agent, or delivered to the Trustee or any paying agent for

cancellation or that have previously been canceled; (b) Securities or portions thereof for the payment or redemption of which moneys or Governmental Obligations in the necessary amount shall have been deposited in trust with the Trustee or with any paying agent (other than the Company) or shall have been set aside and segregated in trust by the Company (if the Company shall act as its own paying agent); provided , however , that if such Securities or portions of such Securities are to be redeemed prior to the maturity thereof, notice of such redemption shall have been given as provided in Article 3 , or provision satisfactory to the Trustee shall have been made for giving such notice; and (c) Securities in lieu of or in substitution for which other Securities shall have been authenticated and delivered pursuant to the terms of Section 2.07 .

“ Person ” means any individual, corporation, partnership, joint venture, joint-stock company, limited liability company, association, trust, unincorporated organization, any other entity or organization, including a government or political subdivision or an agency or instrumentality thereof.

“ Predecessor Security ” of any particular Security means every previous Security evidencing all or a portion of the same debt as that evidenced by such particular Security; and, for the purposes of this definition, any Security authenticated and delivered under Section 2.07 in lieu of a lost, destroyed or stolen Security shall be deemed to evidence the same debt as the lost, destroyed or stolen Security.

“ Responsible Officer ” when used with respect to the Trustee means any officer within the corporate trust department of the Trustee, including any vice president, assistant vice president, assistant secretary, assistant treasurer, trust officer or any other officer of the Trustee who customarily performs functions similar to those performed by the Persons who at the time shall be such officers, respectively, or to whom any corporate trust matter relating to this Indenture is referred because of such person’s knowledge of and familiarity with the particular subject and, in each case, who shall have direct responsibility for the administration of this Indenture (which, for the avoidance of doubt, includes without limitation any supplemental indenture hereto).

“ Securities ” has the meaning stated in the first recital of this Indenture and more particularly means any Securities authenticated and delivered under this Indenture.

“ Securityholder ”, “ holder ”, “ registered holder ”, or other similar term, means the Person or Persons in whose name or names a particular Security is registered on the Security Register kept for that purpose in accordance with the terms of this Indenture.

“ Security Register ” and “ Security Registrar ” shall have the meanings as set forth in Section 2.05 .

“ Subsidiary ” means, with respect to any Person:

(1) any corporation or company a majority of whose capital stock with voting power, under ordinary circumstances, to elect directors is, at the date of determination, directly or indirectly, owned by such Person (a “ subsidiary ”), by one or more subsidiaries of such Person or by such Person and one or more subsidiaries of such Person;

(2) a partnership in which such Person or a subsidiary of such Person is, at the date of determination, a general partner of such partnership; or

(3) any partnership, limited liability company or other Person in which such Person, a subsidiary of such Person or such Person and one or more subsidiaries of such Person, directly or indirectly, at the date of determination, have (x) at least a majority ownership interest or (y) the power to elect or appoint or direct the election or appointment of the managing partner or member of such Person or, if applicable, a majority of the directors or other governing body of such Person.

“ Trustee ” means , and, subject to the provisions of Article 7 , shall also include its successors and assigns, and, if at any time there is more than one Person acting in such capacity hereunder, “Trustee” shall mean each such Person. The term “Trustee” as used with respect to a particular series of the Securities shall mean the trustee with respect to that series.

“ Trust Indenture Act ” means the Trust Indenture Act of 1939, as amended and in effect from time to time.

“ U.S. dollar ” or “ $ ” means the lawful currency of the United States of America.

ARTICLE 2
ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES

Section 2.01 Designation and Terms of Securities .

(a) The aggregate principal amount of Securities that may be authenticated and delivered under this Indenture is unlimited. The Securities may be issued in one or more series up to the aggregate principal amount of Securities of that series from time to time authorized by or pursuant to a Board Resolution or pursuant to one or more indentures supplemental hereto. Prior to the initial issuance of Securities of any series, there shall be established in or pursuant to a Board Resolution, and set forth in an Officer’s Certificate or established in one or more indentures supplemental hereto:

(1) the title of the Securities of the series (which shall distinguish the Securities of that series from all other Securities);

(2) any limit upon the aggregate principal amount of the Securities of that series which may be authenticated and delivered under this Indenture (except for Securities authenticated and delivered upon registration of transfer of, or in exchange for, or in lieu of, other Securities of that series);

(3) the date or dates on which the principal of the Securities of the series is payable;

(4) if the price (expressed as a percentage of the aggregate principal amount thereof) at which such Securities will be issued is a price other than the principal amount thereof, the portion of the principal amount thereof payable upon declaration of

acceleration of the maturity thereof, or if applicable, the portion of the principal amount of such Securities that is convertible into another security or the method by which any such portion shall be determined;

(5) the rate or rates at which the Securities of the series shall bear interest or the manner of calculation of such rate or rates, if any;

(6) the date or dates from which such interest shall accrue, the Interest Payment Dates on which such interest will be payable or the manner of determination of such Interest Payment Dates, the place(s) of payment, and the record date for the determination of holders to whom interest is payable on any such Interest Payment Dates or the manner of determination of such record dates;

(7) the right, if any, to extend the interest payment periods and the duration of such extension;

(8) the period or periods within which, the price or prices at which and the terms and conditions upon which Securities of the series may be redeemed, converted or exchanged, in whole or in part;

(9) the obligation, if any, of the Company to redeem or purchase Securities of the series pursuant to any sinking fund, mandatory redemption, or analogous provisions (including payments made in cash in satisfaction of future sinking fund obligations) or at the option of a holder thereof and the period or periods within which, the price or prices at which, and the terms and conditions upon which, Securities of the series shall be redeemed or purchased, in whole or in part, pursuant to such obligation;

(10) the form of the Securities of the series including the form of the Certificate of Authentication for such series;

(11) if other than minimum denominations of one thousand U.S. dollars ($1,000) or any integral multiple of $1,000 thereof, the denominations in which the Securities of the series shall be issuable;

(12) any and all other terms (including terms, to the extent applicable, relating to any auction or remarketing of the Securities of that series and any security for the obligations of the Company with respect to such Securities) with respect to such series (which terms shall not be inconsistent with the terms of this Indenture, as amended by any supplemental indenture) including any terms which may be required by or advisable under United States laws or regulations or advisable in connection with the marketing of Securities of that series;

(13) whether the Securities of the series shall be issued in whole or in part in the form of a Global Security or Securities; the terms and conditions, if any, upon which such Global Security or Securities may be exchanged in whole or in part for other individual Securities; and the Depositary for such Global Security or Securities;

(14) whether the Securities will be convertible into or exchangeable for shares of common stock, preferred stock or other securities of the Company or any other Person and, if so, the terms and conditions upon which such Securities will be so convertible or exchangeable, including the conversion or exchange price, as applicable, or how it will be calculated and may be adjusted, any mandatory or optional (at the Company’s option or the holders’ option) conversion or exchange features, and the applicable conversion or exchange period;

(15) if other than the full principal amount thereof, the portion of the principal amount of Securities of the series which shall be payable upon declaration of acceleration of the maturity thereof pursuant to Section 6.01 ;

(16) any additional or alternative Events of Default;

(17) additional or alternative covenants (which may include, among other restrictions, restrictions on the Company’s ability or the ability of the Company’s Subsidiaries to: incur additional indebtedness; issue additional securities; create liens; pay dividends or make distributions in respect of the capital stock of the Company or the Company’s Subsidiaries; redeem capital stock; place restrictions on the Company’s Subsidiaries’ ability to pay dividends, make distributions or transfer assets; make investments or other restricted payments; sell or otherwise dispose of assets; enter into sale-leaseback transactions; engage in transactions with stockholders or affiliates; issue or sell stock of the Company’s Subsidiaries; or effect a consolidation or merger) or financial covenants (which may include, among other financial covenants, financial covenants that require the Company and its Subsidiaries to maintain specified interest coverage, fixed charge, cash flow-based, asset-based or other financial ratios) provided for with respect to the Securities of the series;

(18) the currency or currencies, including composite currencies, in which payment of the principal of (and premium, if any) and interest, if any, on such Securities shall be payable (if other than the currency of the United States of America), which unless otherwise specified shall be the currency of the United States of America as at the time of payment is legal tender for payment of public or private debts;

(19) if the principal of (and premium, if any) or interest, if any, on such Securities is to be payable, at the election of the Company or any holder thereof, in a coin or currency other than that in which such Securities are stated to be payable, then the period or periods within which, and the terms and conditions upon which, such election may be made;

(20) whether interest will be payable in cash or additional Securities at the Company’s or the Securityholders’ option and the terms and conditions upon which the election may be made;

(21) the terms and conditions, if any, upon which the Company shall pay amounts in addition to the stated interest, premium, if any and principal amounts of

the Securities of the series to any Securityholder that is not a “United States person” for federal tax purposes;

(22) additional or alternative provisions, if any, related to defeasance and discharge of the offered Securities;

(23) the applicability of any guarantees;

(24) any restrictions on transfer, sale or assignment of the Securities of the series; and

(25) any other terms of the series.

All Securities of any one series shall be substantially identical except as may otherwise be provided in or pursuant to any such Board Resolution or in any indentures supplemental hereto.

If any of the terms of the series are established by action taken pursuant to a Board Resolution of the Company, a copy of an appropriate record of such action shall be certified by the secretary or an assistant secretary of the Company and delivered to the Trustee at or prior to the delivery of the Officer’s Certificate of the Company setting forth the terms of the series.

Securities of any particular series may be issued at various times, with different dates on which the principal or any installment of principal is payable, with different rates of interest, if any, or different methods by which rates of interest may be determined, with different dates on which such interest may be payable and with different redemption dates.

Section 2.02 Form of Securities and Trustee’s Certificate .

The Securities of any series and the Trustee’s certificate of authentication to be borne by such Securities shall be substantially of the tenor and purport as set forth in one or more indentures supplemental hereto or as provided in a Board Resolution, and set forth in an Officer’s Certificate, and they may have such letters, numbers or other marks of identification or designation and such legends or endorsements printed, lithographed or engraved thereon as the Company may deem appropriate and as are not inconsistent with the provisions of this Indenture, or as may be required to comply with any law or with any rule or regulation made pursuant thereto or with any rule or regulation of any securities exchange on which Securities of that series may be listed, or to conform to usage.

Section 2.03 Denominations: Provisions for Payment .

The Securities shall be issuable as registered Securities and in the minimum denominations of one thousand U.S. dollars ($1,000) or any integral multiple of $1,000 thereof, subject to Section 2.01(a)(11). The Securities of a particular series shall bear interest payable on the dates and at the rate specified with respect to that series. Subject to Section 2.01(a)(18) , the principal of and the interest on the Securities of any series, as well as any premium thereon in case of redemption thereof prior to maturity, shall be payable in the coin or currency of the United States of America that at the time is legal tender for public and private debt, at the office

or agency of the Company maintained for that purpose. Each Security shall be dated the date of its authentication. Interest on the Securities shall be computed on the basis of a 360-day year composed of twelve 30-day months.

The interest installment on any Security that is payable, and is punctually paid or duly provided for, on any Interest Payment Date for Securities of that series shall be paid to the Person in whose name said Security (or one or more Predecessor Securities) is registered at the close of business on the regular record date for such interest installment. In the event that any Security of a particular series or portion thereof is called for redemption and the redemption date is subsequent to a regular record date with respect to any Interest Payment Date and prior to such Interest Payment Date, interest on such Security will be paid upon presentation and surrender of such Security as provided in Section 3.03 .

Any interest on any Security that is payable, but is not punctually paid or duly provided for, on any Interest Payment Date for Securities of the same series (herein called “ Defaulted Interest ”) shall forthwith cease to be payable to the registered holder on the relevant regular record date by virtue of having been such holder; and such Defaulted Interest shall be paid by the Company, at its election, as provided in clause (1) or clause (2) below:

(1) The Company may elect to make payment of any Defaulted Interest on Securities to the Persons in whose names such Securities (or their respective Predecessor Securities) are registered at the close of business on a special record date for the payment of such Defaulted Interest, which shall be fixed in the following manner: the Company shall notify the Trustee in writing of the amount of Defaulted Interest proposed to be paid on each such Security and the date of the proposed payment, and at the same time the Company shall deposit with the Trustee an amount of money equal to the aggregate amount proposed to be paid in respect of such Defaulted Interest or shall make arrangements satisfactory to the Trustee for such deposit prior to the date of the proposed payment, such money when deposited to be held in trust for the benefit of the Persons entitled to such Defaulted Interest as in this clause provided. Thereupon the Company shall fix a special record date for the payment of such Defaulted Interest which shall not be more than 15 nor less than 10 days prior to the date of the proposed payment and not less than 10 days after the receipt by the Trustee of the notice of the proposed payment. The Company shall promptly notify the Trustee in writing of such special record date and in such notice, instruct the Trustee to send such notice to holders, in the name and at the expense of the Company, shall cause notice of the proposed payment of such Defaulted Interest and the special record date therefor to be sent electronically or mailed, first class postage prepaid, to each Securityholder at his or her address as it appears in the Security Register (as hereinafter defined), not less than 10 days prior to such special record date. Notice of the proposed payment of such Defaulted Interest and the special record date therefor having been sent as aforesaid, such Defaulted Interest shall be paid to the Persons in whose names such Securities (or their respective Predecessor Securities) are registered on such special record date.

(2) The Company may make or cause to be made payment of any Defaulted Interest on any Securities in any other lawful manner not inconsistent with the requirements of any securities exchange on which such Securities may be listed, and

upon such notice as may be required by such exchange, if, after notice given by the Company to the Trustee of the proposed payment pursuant to this clause, such manner of payment shall be deemed practicable by the Trustee.

Unless otherwise set forth in a Board Resolution or one or more indentures supplemental hereto establishing the terms of any series of Securities pursuant to Section 2.01 hereof, the term “regular record date” as used in this Section with respect to a series of Securities and any Interest Payment Date for such series shall mean either (i) the fifteenth day of the month immediately preceding the month in which an Interest Payment Date established for such series pursuant to Section 2.01 hereof shall occur, if such Interest Payment Date is the first day of a month, or (ii) the first day of the month in which an Interest Payment Date established for such series pursuant to Section 2.01 hereof shall occur, if such Interest Payment Date is the fifteenth day of a month, whether or not such date is a Business Day.

Subject to the foregoing provisions of this Section, each Security of a series delivered under this Indenture upon transfer of or in exchange for or in lieu of any other Security of such series shall carry the rights to interest accrued and unpaid, and to accrue, that were carried by such other Security.

Section 2.04 Execution and Authentications .

The Securities shall be signed on behalf of the Company by one of its Officers. Signatures may be in the form of a manual or facsimile signature.

The Company may use the facsimile signature of any Person who shall have been an Officer, notwithstanding the fact that at the time the Securities shall be authenticated and delivered or disposed of such Person shall have ceased to be such an officer of the Company. The Securities may contain such notations, legends or endorsements required by law, stock exchange rule or usage. Each Security shall be dated the date of its authentication by the Trustee.

A Security shall not be valid until authenticated manually by an authorized signatory of the Trustee, or by an Authenticating Agent. Such signature shall be conclusive evidence that the Security so authenticated has been duly authenticated and delivered hereunder and that the holder is entitled to the benefits of this Indenture. At any time and from time to time after the execution and delivery of this Indenture, the Company may deliver Securities of any series executed by the Company to the Trustee for authentication, together with a Company Order for the authentication and delivery of such Securities, signed by an Officer, and the Trustee in accordance with such Company Order shall authenticate and deliver such Securities.

In authenticating such Securities and accepting the additional responsibilities under this Indenture in relation to such Securities, the Trustee shall receive, and (subject to Section 7.01 ) shall be fully protected in conclusively relying upon, an Officer’s Certificate and an Opinion of Counsel stating that the form and terms thereof have been established in conformity with the provisions of this Indenture, that all conditions precedent in connection with the issuance, authentication and delivery of such Securities have been met and that such Securities are legal,

valid and binding obligations against the Company, enforceable against it in accordance with its terms, subject to customary exceptions and qualifications.

The Trustee shall not be required to authenticate such Securities if the issue of such Securities pursuant to this Indenture will affect the Trustee’s own rights, duties or immunities under the Securities and this Indenture or otherwise in a manner that is not reasonably acceptable to the Trustee.

Section 2.05 Registration of Transfer and Exchange .

(a) Securities of any series may be exchanged upon presentation thereof at the office or agency of the Company designated for such purpose, for other Securities of such series of authorized denominations, and for a like aggregate principal amount, upon payment of a sum sufficient to cover any tax or other governmental charge in relation thereto, all as provided in this Section. In respect of any Securities so surrendered for exchange, the Company shall execute, the Trustee shall authenticate and such office or agency shall deliver in exchange therefor the Security or Securities of the same series that the Securityholder making the exchange shall be entitled to receive, bearing numbers not contemporaneously outstanding.

(b) The Company shall keep, or cause to be kept, at its office or agency designated for such purpose a register or registers (herein referred to as the “ Security Register ”) in which, subject to such reasonable regulations as it may prescribe, the Company shall register the Securities and the transfers of Securities as in this Article provided and which at all reasonable times shall be open for inspection by the Trustee. The registrar for the purpose of registering Securities and transfer of Securities as herein provided shall be appointed as authorized by Board Resolution (the “ Security Registrar ”).

Upon surrender for transfer of any Security at the office or agency of the Company designated for such purpose, the Company shall execute, the Trustee shall authenticate and such office or agency shall deliver in the name of the transferee or transferees a new Security or Securities of the same series as the Security presented for a like aggregate principal amount.

All Securities presented or surrendered for exchange or registration of transfer, as provided in this Section, shall be accompanied (if so required by the Company or the Security Registrar) by a written instrument or instruments of transfer, in form satisfactory to the Company or the Security Registrar, duly executed by the registered holder or by such holder’s duly authorized attorney in writing.

(c) Except as provided pursuant to Section 2.01 pursuant to a Board Resolution, and set forth in an Officer’s Certificate, or established in one or more indentures supplemental to this Indenture, no service charge shall be made for any exchange or registration of transfer of Securities, or issue of new Securities in case of partial redemption of any series, but the Company may require payment of a sum sufficient to cover any tax or other governmental charge in relation thereto, other than exchanges pursuant to Section 2.06 , Section 3.03(b) and Section 9.04 not involving any transfer.

(d) The Company shall not be required (i) to issue, exchange or register the transfer of any Securities during a period beginning at the opening of business 15 days before the

day of the mailing of a notice of redemption of less than all the Outstanding Securities of the same series and ending at the close of business on the day of such mailing, nor (ii) to register the transfer of or exchange any Securities of any series or portions thereof called for redemption, other than the unredeemed portion of any such Securities being redeemed in part. The provisions of this Section 2.05 are, with respect to any Global Security, subject to Section 2.11 hereof.

The Trustee shall have no obligation or duty to monitor, determine or inquire as to compliance with any restrictions on transfer imposed under this Indenture or under applicable law with respect to any transfer of any interest in any Security (including any transfers between or among depositary participants or beneficial owners of interests in any Global Security) other than to require delivery of such certificates and other documentation or evidence as are expressly required by, and to do so if and when expressly required by the terms of, this Indenture, and to examine the same to determine substantial compliance as to form with the express requirements hereof.

Neither the Trustee nor any Agent shall have any responsibility or liability for any actions taken or not taken by the Depositary.

Section 2.06 Temporary Securities .

Pending the preparation of definitive Securities of any series, the Company may execute, and the Trustee shall, upon receipt of a Company Order, authenticate and deliver, temporary Securities (printed, lithographed or typewritten) of any authorized denomination. Such temporary Securities shall be substantially in the form of the definitive Securities in lieu of which they are issued, but with such omissions, insertions and variations as may be appropriate for temporary Securities, all as may be determined by the Company. Every temporary Security of any series shall be executed by the Company and be authenticated by the Trustee upon the same conditions and in substantially the same manner, and with like effect, as the definitive Securities of such series. Without unnecessary delay the Company will execute and will furnish definitive Securities of such series and thereupon any or all temporary Securities of such series may be surrendered in exchange therefor (without charge to the holders), at the office or agency of the Company designated for the purpose, and the Trustee shall, upon receipt of a Company Order, authenticate and such office or agency shall deliver in exchange for such temporary Securities an equal aggregate principal amount of definitive Securities of such series, unless the Company advises the Trustee to the effect that definitive Securities need not be executed and furnished until further notice from the Company. Until so exchanged, the temporary Securities of such series shall be entitled to the same benefits under this Indenture as definitive Securities of such series authenticated and delivered hereunder.

Section 2.07 Mutilated, Destroyed, Lost or Stolen Securities .

In case any temporary or definitive Security shall become mutilated or be destroyed, lost or stolen, the Company (subject to the next succeeding sentence) shall execute, and upon receipt of a Company Order the Trustee (subject as aforesaid) shall authenticate and deliver, a new Security of the same series, bearing a number not contemporaneously outstanding, in exchange and substitution for the mutilated Security, or in lieu of and in substitution for the Security so destroyed, lost or stolen. In every case the applicant for a substituted Security shall furnish to the

Company and the Trustee such security or indemnity as may be required by them to save each of them harmless, and, in every case of destruction, loss or theft, the applicant shall also furnish to the Company and the Trustee evidence to their satisfaction of the destruction, loss or theft of the applicant’s Security and of the ownership thereof. The Trustee may authenticate any such substituted Security and deliver the same upon receipt of a Company Order. Upon the issuance of any substituted Security, the Company may require the payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in relation thereto and any other expenses (including the fees and expenses of the Trustee) connected therewith.

In case any Security that has or is about to become due and payable, whether upon maturity of the Securities of a series or upon declaration or otherwise shall become mutilated or be destroyed, lost or stolen, the Company may, instead of issuing a substitute Security, pay or authorize the payment of the same (without surrender thereof except in the case of a mutilated Security) if the applicant for such payment shall furnish to the Company and the Trustee such security or indemnity as they may require to save them harmless, and, in case of destruction, loss or theft, evidence to the satisfaction of the Company and the Trustee of the destruction, loss or theft of such Security and of the ownership thereof.

Every replacement Security issued pursuant to the provisions of this Section shall constitute an additional contractual obligation of the Company whether or not the mutilated, destroyed, lost or stolen Security shall be found at any time, or be enforceable by anyone, and shall be entitled to all the benefits of this Indenture equally and proportionately with any and all other Securities of the same series duly issued hereunder. All Securities shall be held and owned upon the express condition that the foregoing provisions are exclusive with respect to the replacement or payment of mutilated, destroyed, lost or stolen Securities, and shall preclude (to the extent lawful) any and all other rights or remedies, notwithstanding any law or statute existing or hereafter enacted to the contrary with respect to the replacement or payment of negotiable instruments or other securities without their surrender.

Section 2.08 Cancellation .

All Securities surrendered for the purpose of payment, redemption, exchange or registration of transfer shall, if surrendered to the Company or any paying agent, be delivered to the Trustee for cancellation, or, if surrendered to the Trustee, shall be cancelled by it, and no Securities shall be issued in lieu thereof except as expressly required or permitted by any of the provisions of this Indenture. On written request of the Company at the time of such surrender, the Trustee shall deliver to the Company evidence of cancellation for such canceled Securities held by the Trustee. The Trustee shall cancel and dispose of canceled Securities in accordance with its standard procedures and deliver a certificate of disposition to the Company. If the Company shall otherwise acquire any of the Securities, however, such acquisition shall not operate as a redemption or satisfaction of the indebtedness represented by such Securities unless and until the same are delivered to the Trustee for cancellation.

Section 2.09 Benefits of Indenture .

Nothing in this Indenture or in the Securities, express or implied, shall give or be construed to give to any Person, other than the parties hereto and the holders of the

Securities any legal or equitable right, remedy or claim under or in respect of this Indenture, or under any covenant, condition or provision herein contained; all such covenants, conditions and provisions being for the sole benefit of the parties hereto and of the holders of the Securities.

Section 2.10 Authenticating Agent .

So long as any of the Securities of any series remain Outstanding there may be an Authenticating Agent for any or all such series of Securities which the Trustee shall have the right to appoint. Said Authenticating Agent shall be authorized to act on behalf of the Trustee to authenticate Securities of such series issued upon exchange, transfer or partial redemption thereof, and Securities so authenticated shall be entitled to the benefits of this Indenture and shall be valid and obligatory for all purposes as if authenticated by the Trustee hereunder. All references in this Indenture to the authentication of Securities by the Trustee shall be deemed to include authentication by an Authenticating Agent for such series. Each Authenticating Agent shall be acceptable to the Company and shall be a corporation that has a combined capital and surplus, as most recently reported or determined by it, sufficient under the laws of any jurisdiction under which it is organized or in which it is doing business to conduct a trust business, and that is otherwise authorized under such laws to conduct such business and is subject to supervision or examination by federal or state authorities. If at any time any Authenticating Agent shall cease to be eligible in accordance with these provisions, it shall resign immediately.

Any Authenticating Agent may at any time resign by giving written notice of resignation to the Trustee and to the Company. The Trustee may at any time (and upon request by the Company shall) terminate the agency of any Authenticating Agent by giving written notice of termination to such Authenticating Agent and to the Company. Upon resignation, termination or cessation of eligibility of any Authenticating Agent, the Trustee may appoint an eligible successor Authenticating Agent acceptable to the Company. Any successor Authenticating Agent, upon acceptance of its appointment hereunder, shall become vested with all the rights, powers and duties of its predecessor hereunder as if originally named as an Authenticating Agent pursuant hereto.

Section 2.11 Global Securities .

(a) If the Company shall establish pursuant to Section 2.01 that the Securities of a particular series are to be issued as a Global Security, then the Company shall execute and the Trustee shall, in accordance with Section 2.04 , authenticate and deliver, a Global Security that (i) shall represent, and shall be denominated in an amount equal to the aggregate principal amount of, all of the Outstanding Securities of such series, (ii) shall be registered in the name of the Depositary or its nominee, (iii) shall be delivered by the Trustee to the Depositary or held by it, pursuant to the Depositary’s instruction and (iv) shall bear a legend substantially to the following effect: “Except as otherwise provided in Section 2.11 of the Indenture, this Security may be transferred, in whole but not in part, only to another nominee of the Depositary or to a successor Depositary or to a nominee of such successor Depositary.”

(b) Notwithstanding the provisions of Section 2.05 , the Global Security of a series may be transferred, in whole but not in part and in the manner provided in Section 2.05 ,

only to another nominee of the Depositary for such series, or to a successor Depositary for such series selected or approved by the Company or to a nominee of such successor Depositary.

(c) If at any time the Depositary for a series of the Securities notifies the Company that it is unwilling or unable to continue as Depositary for such series or if at any time the Depositary for such series shall no longer be registered or in good standing under the Exchange Act, or other applicable statute or regulation, and a successor Depositary for such series is not appointed by the Company within 90 days after the Company receives such notice or becomes aware of such condition, as the case may be, or if an Event of Default has occurred and is continuing and the Company has received a request from the Depositary or from the Trustee, this Section 2.11 shall no longer be applicable to the Securities of such series and the Company will execute, and subject to Section 2.04 , the Trustee will authenticate and deliver the Securities of such series in definitive registered form without coupons, in authorized denominations, and in an aggregate principal amount equal to the principal amount of the Global Security of such series in exchange for such Global Security. In addition, the Company may at any time determine that the Securities of any series shall no longer be represented by a Global Security and that the provisions of this Section 2.11 shall no longer apply to the Securities of such series. In such event the Company will execute and, subject to Section 2.04 , the Trustee, upon receipt of an Officer’s Certificate and a Company Order evidencing such determination by the Company, will authenticate and deliver the Securities of such series in definitive registered form without coupons, in authorized denominations, and in an aggregate principal amount equal to the principal amount of the Global Security of such series in exchange for such Global Security. Upon the exchange of the Global Security for such Securities in definitive registered form without coupons, in authorized denominations, the Global Security shall be canceled by the Trustee. Such Securities in definitive registered form issued in exchange for the Global Security pursuant to this Section 2.11(c) shall be registered in such names and in such authorized denominations as the Depositary, pursuant to instructions from its direct or indirect participants or otherwise, shall instruct the Trustee in writing. The Trustee shall deliver such Securities to the Depositary for delivery to the Persons in whose names such Securities are so registered.

ARTICLE 3
REDEMPTION OF SECURITIES AND SINKING FUND PROVISIONS

Section 3.01 Redemption .

The Company may redeem the Securities of any series issued hereunder on and after the dates and in accordance with the terms established for such series pursuant to Section 2.01 hereof.

Section 3.02 Notice of Redemption .

such redemption not less than 15 days and not more than 90 days, except that redemption notices may be sent more than 90 days prior to the redemption date if the notice is issued in connection with a defeasance of the Securities or a satisfaction and discharge, before the date fixed for redemption of that series to such holders (with a copy to the Trustee) at their last addresses as they shall appear upon the Security Register, unless a shorter period is specified in the Securities to be redeemed. Any notice that is mailed in the manner herein provided shall be conclusively presumed to have been duly given, whether or not the registered holder receives the notice. In any case, failure duly to give such notice to the holder of any Security of any series designated for redemption in whole or in part, or any defect in the notice, shall not affect the validity of the proceedings for the redemption of any other Securities of such series or any other series. In the case of any redemption of Securities prior to the expiration of any restriction on such redemption provided in the terms of such Securities or elsewhere in this Indenture, the Company shall furnish the Trustee with an Officer’s Certificate evidencing compliance with any such restriction.

Each such notice of redemption shall specify the date fixed for redemption, if applicable, any record date with respect to such redemption and the redemption price at which Securities of that series are to be redeemed, and shall state that payment of the redemption price of such Securities to be redeemed will be made at the office or agency of the Company, upon presentation and surrender of such Securities, that interest accrued to the date fixed for redemption will be paid as specified in said notice, that from and after said date interest will cease to accrue and that the redemption is from a sinking fund, if such is the case. If less than all the Securities of a series are to be redeemed, the notice to the holders of Securities of that series to be redeemed in part shall specify the particular Securities to be so redeemed.

In case any Security is to be redeemed in part only, the notice that relates to such Security shall state the portion of the principal amount thereof to be redeemed, and shall state that on and after the redemption date, upon surrender of such Security, a new Security or Securities of such series in principal amount equal to the unredeemed portion thereof will be issued.

(b) If less than all the Securities of a series are to be redeemed, the Company shall give the Trustee at least 20 days’ notice (unless a shorter notice shall be satisfactory to the Trustee) in advance of the date fixed for redemption as to the aggregate principal amount of Securities of the series to be redeemed, and thereupon the Trustee shall select, by lot or in such other manner as it shall deem appropriate and fair in its discretion (and subject to the applicable procedures of the Depositary) and that may provide for the selection of a portion or portions (equal to one thousand U.S. dollars ($1,000) or any integral multiple thereof) of the principal amount of such Securities of a denomination larger than $1,000, the Securities to be redeemed and shall thereafter promptly notify the Company in writing of the numbers of the Securities to be redeemed, in whole or in part. The Company may, if and whenever it shall so elect, by delivery of instructions signed on its behalf by an Officer, instruct the Trustee or any paying agent to call all or any part of the Securities of a particular series for redemption and to send notice of redemption in the manner set forth in this Section, such notice to be in the name and at the expense of the Company. In any case in which notice of redemption is to be sent by the Trustee or any such paying agent, the Company shall deliver or cause to be delivered to, or permit to remain with, the Trustee or such paying agent, as the case may be, such Security Register, transfer books or other records, or suitable copies or extracts therefrom, sufficient to

enable the Trustee or such paying agent to give any notice by mail that may be required under the provisions of this Section.

Section 3.03 Payment Upon Redemption .

(a) If the giving of notice of redemption shall have been completed as above provided, the Securities or portions of Securities of the series to be redeemed specified in such notice shall become due and payable on the date and at the place stated in such notice at the applicable redemption price, together with interest accrued to the date fixed for redemption and interest on such Securities or portions of Securities shall cease to accrue on and after the date fixed for redemption, unless the Company shall default in the payment of such redemption price and accrued interest with respect to any such Security or portion thereof. On presentation and surrender of such Securities on or after the date fixed for redemption at the place of payment specified in the notice, said Securities shall be paid and redeemed at the applicable redemption price for such series, together with interest accrued thereon to the date fixed for redemption (but if the date fixed for redemption is an interest payment date, the interest installment payable on such date shall be payable to the registered holder at the close of business on the applicable record date pursuant to Section 2.03 ).

(b) Upon presentation of any physical Security of such series that is to be redeemed in part only, the Company shall execute and the Trustee shall authenticate and the office or agency where the Security is presented shall deliver to the holder thereof, at the expense of the Company, a new Security of the same series of authorized denominations in principal amount equal to the unredeemed portion of the Security so presented.

Section 3.04 Sinking Fund .

The provisions of Sections 3.04 , 3.05 and 3.06 shall be applicable to any sinking fund for the retirement of Securities of a series, except as otherwise specified as contemplated by Section 2.01 for Securities of such series.

The minimum amount of any sinking fund payment provided for by the terms of Securities of any series is herein referred to as a “mandatory sinking fund payment,” and any payment in excess of such minimum amount provided for by the terms of Securities of any series is herein referred to as an “optional sinking fund payment”. If provided for by the terms of Securities of any series, the cash amount of any sinking fund payment may be subject to reduction as provided in Section 3.05 . Each sinking fund payment shall be applied to the redemption of Securities of any series as provided for by the terms of Securities of such series.

Section 3.05 Satisfaction of Sinking Fund Payments with Securities .

The Company (i) may deliver Outstanding Securities of a series and (ii) may apply as a credit Securities of a series that have been redeemed either at the election of the Company pursuant to the terms of such Securities or through the application of permitted optional sinking fund payments pursuant to the terms of such Securities, in each case in satisfaction of all or any part of any sinking fund payment with respect to the Securities of such series required to be made pursuant to the terms of such Securities as provided for by the terms of such series, provided that such Securities have not been previously so credited. Such Securities shall be

received and credited for such purpose by the Trustee at the redemption price specified in such Securities for redemption through operation of the sinking fund and the amount of such sinking fund payment shall be reduced accordingly.

Section 3.06 Redemption of Securities for Sinking Fund .

Not less than 45 days prior to each sinking fund payment date for any series of Securities (unless a shorter period shall be satisfactory to the Trustee), the Company will deliver to the Trustee an Officer’s Certificate specifying the amount of the next ensuing sinking fund payment for that series pursuant to the terms of the series, the portion thereof, if any, that is to be satisfied by delivering and crediting Securities of that series pursuant to Section 3.05 and the basis for such credit and will, together with such Officer’s Certificate, deliver to the Trustee any Securities to be so delivered. Not less than 30 days before each such sinking fund payment date the Trustee shall select the Securities to be redeemed upon such sinking fund payment date in the manner specified in Section 3.02 and cause notice of the redemption thereof to be given in the name of and at the expense of the Company in the manner provided in Section 3.02 . Such notice having been duly given, the redemption of such Securities shall be made upon the terms and in the manner stated in Section 3.03 .

ARTICLE 4
COVENANTS

Section 4.01 Payment of Principal, Premium and Interest .

The Company will duly and punctually pay or cause to be paid the principal of (and premium, if any) and interest on the Securities of that series at the time and place and in the manner provided herein and established with respect to such Securities. Payments of principal on the physical Securities may be made at the time provided herein and established with respect to such Securities by U.S. dollar check drawn on and mailed to the address of the Securityholder entitled thereto as such address shall appear in the Security Register, or U.S. dollar wire transfer to, a U.S. dollar account if such Securityholder shall have furnished wire instructions to the Trustee no later than 15 days prior to the relevant payment date. Payments of interest on the Securities may be made at the time provided herein and established with respect to such Securities by U.S. dollar check mailed to the address of the Securityholder entitled thereto as such address shall appear in the Security Register, or U.S. dollar wire transfer to an account in the United States if such Securityholder shall have furnished wire instructions in writing to the Security Registrar and the Trustee no later than 15 days prior to the relevant payment date.

Section 4.02 Maintenance of Office or Agency .

So long as any series of the Securities remain Outstanding, the Company agrees to maintain an office or agency with respect to each such series and at such other location or locations as may be designated as provided in this Section 4.02 , where (i) Securities of that series may be presented for payment, (ii) Securities of that series may be presented as herein above authorized for registration of transfer and exchange, and (iii) notices in respect of the Securities of that series and this Indenture may be given or made, such designation to continue with respect to such office or agency until the Company shall, by written notice in an Officer’s Certificate and

delivered to the Trustee, designate some other office or agency for such purposes or any of them. If at any time the Company shall fail to maintain any such required office or agency or shall fail to furnish the Trustee with the address thereof, such presentations and notices may be made at the Corporate Trust Office of the Trustee, and the Company hereby appoints the Trustee as its agent to receive all such presentations and notices; provided, however, the Trustee shall not be considered an agent of the Company for service of process.

Section 4.03 Paying Agents .

(a) If the Company shall appoint one or more paying agents for all or any series of the Securities, other than the Trustee, the Company will cause each such paying agent to execute and deliver to the Trustee an instrument in which such agent shall agree with the Trustee, subject to the provisions of this Section:

(1) that it will hold all sums held by it as such agent for the payment of the principal of (and premium, if any) or interest on the Securities of that series (whether such sums have been paid to it by the Company or by any other obligor of such Securities) in trust for the benefit of the Persons entitled thereto;

(2) that it will give the Trustee notice of any failure by the Company (or by any other obligor of such Securities) to make any payment of the principal of (and premium, if any) or interest on the Securities of that series when the same shall be due and payable;

(3) that it will, at any time during the continuance of any failure referred to in the preceding paragraph (a)(2) above, upon the written request of the Trustee, forthwith pay to the Trustee all sums so held in trust by such paying agent;

(4) that upon any receivership, insolvency, liquidation, bankruptcy, reorganization, readjustment, arrangement, composition or judicial proceedings affecting the Company, the Trustee will automatically be the Paying Agent; and

(5) that it will perform all other duties of paying agent as set forth in this Indenture.

(b) If the Company shall act as its own paying agent with respect to any series of the Securities, it will on or before each due date of the principal of (and premium, if any) or interest on Securities of that series, set aside, segregate and hold in trust for the benefit of the Persons entitled thereto a sum sufficient to pay such principal (and premium, if any) or interest so becoming due on Securities of that series until such sums shall be paid to such Persons or otherwise disposed of as herein provided and will promptly notify the Trustee of such action, or any failure (by it or any other obligor on such Securities) to take such action. Whenever the Company shall have one or more paying agents for any series of Securities, it will, prior to each due date of the principal of (and premium, if any) or interest on any Securities of that series, deposit with the paying agent a sum sufficient to pay the principal (and premium, if any) or interest so becoming due, such sum to be held in trust for the benefit of the Persons entitled to such principal, premium or interest, and (unless such paying agent is the Trustee) the Company will promptly notify the Trustee of this action or failure so to act.

(c) Notwithstanding anything in this Section to the contrary, (i) the agreement to hold sums in trust as provided in this Section is subject to the provisions of Section 11.05 , and (ii) the Company may at any time, for the purpose of obtaining the satisfaction and discharge of this Indenture or for any other purpose, pay, or direct any paying agent to pay, to the Trustee all sums held in trust by the Company or such paying agent, such sums to be held by the Trustee upon the same terms and conditions as those upon which such sums were held by the Company or such paying agent; and, upon such payment by the Company or any paying agent to the Trustee, the Company or such paying agent shall be released from all further liability with respect to such money.

(d) The Company initially appoints the Trustee at its Corporate Trust Office as its paying agent with respect to the Securities.

Section 4.04 Appointment to Fill Vacancy in Office of Trustee .

The Company, whenever necessary to avoid or fill a vacancy in the office of Trustee, will appoint, in the manner provided in Section 7.10 , a Trustee, so that there shall at all times be a Trustee hereunder.

Section 4.05 Compliance with Consolidation Provisions .

The Company will not, while any of the Securities remain Outstanding, consolidate with or merge into any other Person, in either case where the Company is not the survivor of such transaction, or sell or convey all or substantially all of its property to any other Person unless the provisions of Article 10 hereof are complied with.

ARTICLE 5
SECURITYHOLDERS’ LISTS AND REPORTS BY THE COMPANY AND THE TRUSTEE

Section 5.01 Company to Furnish Trustee Names and Addresses of Securityholder s.

The Company will furnish or cause to be furnished to the Trustee (a) within 5 days after each regular record date (as defined in Section 2.03 ) a list, in such form as the Trustee may reasonably require, of the names and addresses of the holders of each series of Securities as of such regular record date, provided that the Company shall not be obligated to furnish or cause to be furnished such list at any time that the list shall not differ in any respect from the most recent list furnished to the Trustee by the Company and (b) at such other times as the Trustee may request in writing within 30 days after the receipt by the Company of any such request, a list of similar form and content as of a date not more than 15 days prior to the time such list is furnished; provided , however , that, in either case, no such list need be furnished for any series for which the Trustee shall be the Security Registrar.

Section 5.02 Preservation Of Information; Communications With Securityholders .

addresses of holders of Securities received by the Trustee in its capacity as Security Registrar (if acting in such capacity).

(b) The Trustee may destroy any list furnished to it as provided in Section 5.01 upon receipt of a new list so furnished.

(c) Securityholders may communicate as provided in Section 312(b) of the Trust Indenture Act with other Securityholders with respect to their rights under this Indenture or under the Securities, and, in connection with any such communications, the Trustee shall satisfy its obligations under Section 312(b) of the Trust Indenture Act in accordance with the provisions of Section 312(b) of the Trust Indenture Act.

Section 5.03 Reports by the Company .

(a) The Company covenants and agrees to provide (which delivery may be via electronic mail) to the Trustee within 30 days, after the Company files the same with the Commission, copies of the annual reports and of the information, documents and other reports (or copies of such portions of any of the foregoing as the Commission may from time to time by rules and regulations prescribe) that the Company is required to file with the Commission pursuant to Section 13 or Section 15(d) of the Exchange Act; provided , however , the Company shall not be required to deliver to the Trustee any materials for which the Company has sought and received confidential treatment by the Commission; and provided further , that so long as such filings by the Company are available on the Commission’s Electronic Data Gathering, Analysis and Retrieval System (EDGAR), or Interactive Data Electronic Applications (IDEA), or any successor system, such filings shall be deemed to have been filed with the Trustee for purposes hereof without any further action required by the Company; provided that an electronic link to such filing, together with an electronic notice of such filing have been sent to the Trustee it being understood that the Trustee shall have no responsibility to determine whether such filings have been made. For the avoidance of doubt, a failure by the Company to file annual reports, information and other reports with the Commission within the time period prescribed thereof by the Commission shall not be deemed a breach of this Section 5.03 .

(b) Delivery of reports, information and documents to the Trustee under Section 5.03 is for informational purposes only and the information and the Trustee’s receipt of the foregoing shall not constitute constructive notice of any information contained therein, or determinable from information contained therein including the Company’s compliance with any of their covenants thereunder (as to which the Trustee is entitled to rely exclusively on an Officer’s Certificate).

Section 5.04 Reports by the Trustee .

(a) If required by Section 313(a) of the Trust Indenture Act, the Trustee, within sixty (60) days after each May 15, commencing the calendar year after the year in which the first Securities are issued hereunder, shall transmit by mail, first class postage prepaid, to the Securityholders, as their names and addresses appear upon the Security Register, a brief report dated as of such May 15, which complies with Section 313(a) of the Trust Indenture Act.

(b) The Trustee shall comply with Section 313(b) and 313(c) of the Trust Indenture Act.

(c) A copy of each such report shall, at the time of such transmission to Securityholders, be filed by the Trustee with the Company, with each securities exchange upon which any Securities are listed (if so listed) and also with the Commission. The Company agrees to notify the Trustee in writing when any Securities become listed on any securities exchange or of any delisting thereof.

ARTICLE 6
REMEDIES OF THE TRUSTEE AND SECURITYHOLDERS ON EVENT OF DEFAULT

Section 6.01 Events of Default .

(a) Whenever used herein with respect to Securities of a particular series, “ Event of Default ” means any one or more of the following events that has occurred and is continuing:

(1) the Company defaults in the payment of any installment of interest upon any of the Securities of that series, as and when the same shall become due and payable, and such default continues for a period of 90 days; provided , however , that a valid extension of an interest payment period by the Company in accordance with the terms of any indenture supplemental hereto shall not constitute a default in the payment of interest for this purpose;

(2) the Company defaults in the payment of the principal of (or premium, if any, on) any of the Securities of that series as and when the same shall become due and payable whether at maturity, upon redemption, by declaration or otherwise, or in any payment required by any sinking or analogous fund established with respect to that series; provided , however , that a valid extension of the maturity of such Securities in accordance with the terms of any indenture supplemental hereto shall not constitute a default in the payment of principal or premium, if any;

(3) the Company fails to observe or perform any other of its covenants or agreements with respect to that series contained in this Indenture or otherwise established with respect to that series of Securities pursuant to Section 2.01 hereof (other than a covenant or agreement that has been expressly included in this Indenture solely for the benefit of one or more series of Securities other than such series) for a period of 90 days after the date on which written notice of such failure, requiring the same to be remedied and stating that such notice is a “ Notice of Default ” hereunder, shall have been given to the Company by the Trustee or to the Company and the Trustee by the holders of at least 25% in principal amount of the Securities of that series at the time Outstanding;

for all or substantially all of its property or (iv) makes a general assignment for the benefit of its creditors; or

(5) a court of competent jurisdiction enters an order under any Bankruptcy Law that (i) is for relief against the Company in an involuntary case, (ii) appoints a Custodian of the Company for all or substantially all of its property or (iii) orders the liquidation of the Company, and the order or decree remains unstayed and in effect for 90 days.

(b) In each and every such case (other than an Event of Default specified in clause (4) or clause (5) above), unless the principal of all the Securities of that series shall have already become due and payable, either the Trustee or the holders of not less than 25% in aggregate principal amount of the Securities of that series then Outstanding hereunder, by notice in writing to the Company (and to the Trustee if given by such Securityholders), may declare the principal of (and premium, if any, on) and accrued and unpaid interest on all the Securities of that series to be due and payable immediately, and upon any such declaration the same shall become and shall be immediately due and payable. If an Event of Default specified in clause (4) or clause (5) above occurs, the principal of and accrued and unpaid interest on all the Securities of that series shall automatically be immediately due and payable without any declaration or other act on the part of the Trustee or the holders of the Securities.

(c) At any time after the principal of (and premium, if any, on) and accrued and unpaid interest on the Securities of that series shall have been so declared due and payable, and before any judgment or decree for the payment of the moneys due shall have been obtained or entered as hereinafter provided, the holders of a majority in aggregate principal amount of the Securities of that series then Outstanding hereunder, by written notice to the Company and the Trustee, may rescind and annul such declaration and its consequences if: (i) the Company has paid or deposited with the Trustee a sum sufficient to pay all matured installments of interest upon all the Securities of that series and the principal of (and premium, if any, on) any and all Securities of that series that shall have become due otherwise than by acceleration (with interest upon such principal and premium, if any, and, to the extent that such payment is enforceable under applicable law, upon overdue installments of interest, at the rate per annum expressed in the Securities of that series to the date of such payment or deposit) and the amount payable to the Trustee under Section 7.06 , and (ii) any and all Events of Default under the Indenture with respect to such series, other than the nonpayment of principal on (and premium, if any, on) and accrued and unpaid interest on Securities of that series that shall not have become due by their terms, shall have been remedied or waived as provided in Section 6.06 .

No such rescission and annulment shall extend to or shall affect any subsequent default or impair any right consequent thereon.

(d) In case the Trustee shall have proceeded to enforce any right with respect to Securities of that series under this Indenture and such proceedings shall have been discontinued or abandoned because of such rescission or annulment or for any other reason or shall have been determined adversely to the Trustee, then and in every such case, subject to any determination in such proceedings, the Company and the Trustee shall be restored respectively to

their former positions and rights hereunder, and all rights, remedies and powers of the Company and the Trustee shall continue as though no such proceedings had been taken.

Section 6.02 Collection of Indebtedness and Suits for Enforcement by Trustee .

(a) The Company covenants that if an Event of Default described in Section 6.01(a) or 6.01(b) shall have occurred with respect to the Securities of any series, the Company will pay to the Trustee, for the benefit of the holders of the Securities of that series, the whole amount that then shall have been become due and payable on all such Securities for principal (and premium, if any) or interest, or both, as the case may be, with interest upon the overdue principal (and premium, if any) and (to the extent that payment of such interest is enforceable under applicable law) upon overdue installments of interest at the rate per annum expressed in the Securities of that series; and, in addition thereto, such further amount as shall be sufficient to cover the costs and expenses of collection, and the amount payable to the Trustee under Section 7.06 .

(b) If the Company shall fail to pay such amounts forthwith upon such demand, the Trustee, in its own name and as trustee of an express trust, shall be entitled and empowered to institute any action or proceedings at law or in equity for the collection of the sums so due and unpaid, and may prosecute any such action or proceeding to judgment or final decree, and may enforce any such judgment or final decree against the Company or other obligor upon the Securities of that series and collect the moneys adjudged or decreed to be payable in the manner provided by law or equity out of the property of the Company or other obligor upon the Securities of that series, wherever situated.

(c) In case of any receivership, insolvency, liquidation, bankruptcy, reorganization, readjustment, arrangement, composition or judicial proceedings affecting the Company, or its creditors or property, irrespective of whether the Trustee shall have made any demand pursuant to this Section 6.02, the Trustee shall have power to intervene in such proceedings and take any action therein that may be permitted by the court and shall (except as may be otherwise provided by law) be entitled to file such proofs of claim and other papers and documents as may be necessary or advisable in order to have the claims of the Trustee and of the holders of Securities of such series allowed for the entire amount due and payable by the Company under the Indenture at the date of institution of such proceedings and for any additional amount that may become due and payable by the Company after such date, and to collect and receive any moneys or other property payable or deliverable on any such claim, and to distribute the same after the deduction of the amount payable to the Trustee under Section 7.06 ; and any receiver, assignee or trustee in bankruptcy or reorganization is hereby authorized by each of the holders of Securities of such series to make such payments to the Trustee, and, in the event that the Trustee shall consent to the making of such payments directly to such Securityholders, to pay to the Trustee any amount due it under Section 7.06 .

(d) All rights of action and of asserting claims under this Indenture, or under any of the terms established with respect to Securities of that series, may be enforced by the Trustee without the possession of any of such Securities, or the production thereof at any trial or other proceeding relative thereto, and any such suit or proceeding instituted by the Trustee shall be brought in its own name as trustee of an express trust, and any recovery of judgment shall,

after provision for payment to the Trustee of any amounts due under Section 7.06 , be for the ratable benefit of the holders of the Securities of such series.

In case of an Event of Default hereunder, the Trustee may in its discretion proceed to protect and enforce the rights vested in it by this Indenture by such appropriate judicial proceedings as the Trustee shall deem most effectual to protect and enforce any of such rights, either at law or in equity or in bankruptcy or otherwise, whether for the specific enforcement of any covenant or agreement contained in the Indenture or in aid of the exercise of any power granted in this Indenture, or to enforce any other legal or equitable right vested in the Trustee by this Indenture or by law.

Nothing contained herein shall be deemed to authorize the Trustee to authorize or consent to or accept or adopt on behalf of any Securityholder any plan of reorganization, arrangement, adjustment or composition affecting the Securities of that series or the rights of any holder thereof or to authorize the Trustee to vote in respect of the claim of any Securityholder in any such proceeding.

Section 6.03 Application of Moneys Collected .

Any moneys or properties collected by the Trustee pursuant to this Article with respect to a particular series of Securities shall be applied in the following order, at the date or dates fixed by the Trustee and, in case of the distribution of such moneys on account of principal (or premium, if any) or interest, upon presentation of the Securities of that series, and notation thereon of the payment, if only partially paid, and upon surrender thereof if fully paid:

FIRST : To the payment of reasonable costs and expenses of collection and of all amounts payable to the Trustee, its agents and attorneys under this Indenture;

SECOND : To the payment of the amounts then due and unpaid upon Securities of such series for principal (and premium, if any) and interest, in respect of which or for the benefit of which such money has been collected, ratably, without preference or priority of any kind, according to the amounts due and payable on such Securities for principal (and premium, if any) and interest, respectively; and

THIRD : To the payment of the remainder, if any, to the Company or any other Person lawfully entitled thereto.

Section 6.04 Limitation on Suits .

No holder of any Security of any series shall have any right by virtue or by availing of any provision of this Indenture to institute any suit, action or proceeding in equity or at law upon or under or with respect to this Indenture or for the appointment of a receiver or trustee, or for any other remedy hereunder, unless (i) such holder previously shall have given to the Trustee written notice of an Event of Default and of the continuance thereof with respect to the Securities of such series specifying such Event of Default, as hereinbefore provided; (ii) the holders of not less than 25% in aggregate principal amount of the Securities of such series then Outstanding shall have made written request upon the Trustee to institute such action, suit or proceeding in its own name as Trustee hereunder; (iii) such holder or holders shall have offered to the Trustee

such indemnity reasonably satisfactory to it as it may require against the costs, expenses, claims and liabilities to be incurred therein or thereby; (iv) the Trustee for 90 days after its receipt of such notice, request and offer of indemnity, shall have failed to institute any such action, suit or proceeding and (v) during such 90 day period, the holders of a majority in principal amount of the Securities of that series do not give the Trustee a direction inconsistent with the request.

Notwithstanding anything contained herein to the contrary or any other provisions of this Indenture, the right of any holder of any Security to receive payment of the principal of (and premium, if any) and interest on such Security, as therein provided, on or after the respective due dates expressed in such Security (or in the case of redemption, on the redemption date), or to institute suit for the enforcement of any such payment on or after such respective dates or redemption date, shall not be impaired or affected without the consent of such holder and by accepting a Security hereunder it is expressly understood, intended and covenanted by the taker and holder of every Security of such series with every other such taker and holder and the Trustee, that no one or more holders of Securities of such series shall have any right in any manner whatsoever by virtue or by availing of any provision of this Indenture to affect, disturb or prejudice the rights of the holders of any other of such Securities, or to obtain or seek to obtain priority over or preference to any other such holder, or to enforce any right under this Indenture (it being understood that the Trustee does not have an affirmative duty to ascertain whether or not such actions or forbearances are unduly prejudicial to such holders), except in the manner herein provided and for the equal, ratable and common benefit of all holders of Securities of such series. For the protection and enforcement of the provisions of this Section, each and every Securityholder and the Trustee shall be entitled to such relief as can be given either at law or in equity.

Section 6.05 Rights and Remedies Cumulative; Delay or Omission Not Waiver .

(a) Except as otherwise provided in Section 2.07 , all powers and remedies given by this Article to the Trustee or to the Securityholders shall, to the extent permitted by law, be deemed cumulative and not exclusive of any other powers and remedies available to the Trustee or the holders of the Securities, by judicial proceedings or otherwise, to enforce the performance or observance of the covenants and agreements contained in this Indenture or otherwise established with respect to such Securities.

(b) No delay or omission of the Trustee or of any holder of any of the Securities to exercise any right or power accruing upon any Event of Default occurring and continuing as aforesaid shall impair any such right or power, or shall be construed to be a waiver of any such default or an acquiescence therein; and, subject to the provisions of Section 6.04 , every power and remedy given by this Article or by law to the Trustee or the Securityholders may be exercised from time to time, and as often as shall be deemed expedient, by the Trustee or by the Securityholders.

Section 6.06 Control by Securityholders .

Trustee, or exercising any trust or power conferred on the Trustee with respect to such series; provided , however , that such direction shall not be in conflict with any rule of law or with this Indenture or subject the Trustee in its sole discretion to personal liability. The Trustee shall have the right to decline to follow any such direction if the Trustee in good faith shall determine that the proceeding so directed, subject to the Trustee’s duties under the Trust Indenture Act, would involve the Trustee in personal liability or might be unduly prejudicial to the Securityholders not involved in the proceeding. Prior to taking any action under this Indenture, the Trustee shall be entitled to indemnity or security satisfactory to it against loss, liability or expense that may be caused by taking such action. The holders of a majority in aggregate principal amount of the Securities of any series at the time Outstanding affected thereby, determined in accordance with Section 8.04 , may on behalf of the holders of all of the Securities of such series waive any past default in the performance of any of the covenants contained herein or established pursuant to Section 2.01 with respect to such series and its consequences, except a default in the payment of the principal of, or premium, if any, or interest on, any of the Securities of that series as and when the same shall become due by the terms of such Securities otherwise than by acceleration (unless such default has been cured and a sum sufficient to pay all matured installments of interest and principal and any premium has been deposited with the Trustee (in accordance with Section 6.01(c) ). Upon any such waiver, the default covered thereby shall be deemed to be cured for all purposes of this Indenture and the Company, the Trustee and the holders of the Securities of such series shall be restored to their former positions and rights hereunder, respectively; but no such waiver shall extend to any subsequent or other default or impair any right consequent thereon.

Section 6.07 Undertaking to Pay Costs .

All parties to this Indenture agree, and each holder of any Securities by such holder’s acceptance thereof shall be deemed to have agreed, that any court may in its discretion require, in any suit for the enforcement of any right or remedy under this Indenture, or in any suit against the Trustee for any action taken or omitted by it as Trustee, the filing by any party litigant in such suit of an undertaking to pay the costs of such suit, and that such court may in its discretion assess reasonable costs, including reasonable attorneys’ fees, against any party litigant in such suit, having due regard to the merits and good faith of the claims or defenses made by such party litigant; but the provisions of this Section shall not apply to any suit instituted by the Trustee, to any suit instituted by any Securityholder, or group of Securityholders, holding more than 10% in aggregate principal amount of the Outstanding Securities of any series, or to any suit instituted by any Securityholder for the enforcement of the payment of the principal of (or premium, if any) or interest on any Security of such series, on or after the respective due dates expressed in such Security or established pursuant to this Indenture.

ARTICLE 7
CONCERNING THE TRUSTEE

Section 7.01 Certain Duties and Responsibilities of Trustee .

Securities of such series such duties and only such duties as are specifically set forth in this Indenture, and no implied covenants shall be read into this Indenture against the Trustee. In case an Event of Default with respect to the Securities of a series has occurred (that has not been cured or waived), the Trustee shall exercise with respect to Securities of that series such of the rights and powers vested in it by this Indenture, and use the same degree of care and skill in their exercise, as a prudent person would exercise or use under the circumstances in the conduct of such person’s own affairs.

(b) No provision of this Indenture shall be construed to relieve the Trustee from liability for its own negligent action, its own negligent failure to act, or its own willful misconduct, except that:

(1) prior to the occurrence of an Event of Default with respect to the Securities of a series and after the curing or waiving of all such Events of Default with respect to that series that may have occurred:

(A) the duties and obligations of the Trustee shall with respect to the Securities of such series be determined solely by the express provisions of this Indenture, and the Trustee shall not be liable with respect to the Securities of such series except for the performance of such duties and obligations as are specifically set forth in this Indenture, and no implied covenants or obligations shall be read into this Indenture against the Trustee; and

(B) in the absence of willful misconduct on the part of the Trustee, the Trustee may with respect to the Securities of such series conclusively rely, as to the truth of the statements and the correctness of the opinions expressed therein, upon any certificates or opinions furnished to the Trustee and conforming to the requirements of this Indenture; but in the case of any such certificates or opinions that by any provision hereof are specifically required to be furnished to the Trustee, the Trustee shall be under a duty to examine the same to determine whether or not they conform to the requirements of this Indenture (but need not confirm or investigate the accuracy of mathematical calculations or other facts stated therein);

(2) the Trustee shall not be liable for any error of judgment made in good faith by a Responsible Officer or Responsible Officers of the Trustee, unless it shall be proved that the Trustee was negligent in ascertaining the pertinent facts;

(3) the Trustee shall not be liable with respect to any action taken or omitted to be taken by it in good faith in accordance with the direction of the holders of not less than a majority in principal amount of the Securities of any series at the time Outstanding relating to the time, method and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred upon the Trustee under this Indenture with respect to the Securities of that series; and

there is reasonable ground for believing that the repayment of such funds or liability is not reasonably assured to it under the terms of this Indenture or adequate indemnity against such risk is not reasonably assured to it.

Section 7.02 Certain Rights of Trustee .

Except as otherwise provided in Section 7.01 :

(a) The Trustee may rely and shall be protected in acting or refraining from acting upon any resolution, certificate, statement, instrument, opinion, report, notice, request, consent, order, approval, bond, security or other paper or document or other evidence of indebtedness believed by it to be genuine and to have been signed or presented by the proper party or parties. The Trustee need not investigate any fact or matter stated in the document. The Trustee shall receive and retain financial reports and statements of the Company to the extent provided herein, but shall have no duty to review or analyze such reports or statements to determine compliance with covenants or other obligations of the Company;

(b) Any request, direction, order or demand of the Company mentioned herein shall be sufficiently evidenced by a Board Resolution or an instrument signed in the name of the Company by any authorized Officer of the Company (unless other evidence in respect thereof is specifically prescribed herein);

(c) The Trustee may consult with counsel of its selection and the advice of such counsel or, if requested, any Opinion of Counsel shall be full and complete authorization and protection in respect of any action taken or suffered or omitted hereunder in good faith and in reliance thereon;

(d) The Trustee shall be under no obligation to exercise any of the rights or powers vested in it by this Indenture at the request, order or direction of any of the Securityholders pursuant to the provisions of this Indenture, unless such Securityholders shall have offered (and if requested, provided) to the Trustee security or indemnity satisfactory to it against the costs, expenses, claims and liabilities that may be incurred therein or thereby;

(e) The Trustee shall not be liable for any action taken or omitted to be taken by it in good faith and believed by it to be authorized or within the discretion or rights or powers conferred upon it by this Indenture;

(f) The Trustee shall not be bound to make any investigation into the facts or matters stated in any resolution, certificate, statement, instrument, opinion, report, notice, request, consent, order, approval, bond, security, or other papers or documents or other evidence of indebtedness, unless requested in writing so to do by the holders of not less than a majority in principal amount of the Outstanding Securities of the particular series affected thereby (determined as provided in Section 8.04 ); provided , however , that if the payment within a reasonable time to the Trustee of the costs, expenses, claims or liabilities likely to be incurred by it in the making of such investigation is, in the opinion of the Trustee, not reasonably assured to the Trustee by the security afforded to it by the terms of this Indenture, the Trustee may require indemnity or security satisfactory to it against such costs, expenses, claims or liabilities as a

condition to so proceeding. The reasonable expense of every such examination shall be paid by the Company or, if paid by the Trustee, shall be repaid by the Company upon demand;

(g) The Trustee may execute any of the trusts or powers hereunder or perform any duties hereunder either directly or by or through agents or attorneys and the Trustee shall not be responsible for any misconduct or negligence on the part of any agent or attorney appointed with due care by it hereunder;

(h) In no event shall the Trustee be responsible or liable for any failure or delay in the performance of its obligations hereunder arising out of or caused by, directly or indirectly, forces beyond its control, including, without limitation, strikes, work stoppages, accidents, acts of war or terrorism, civil or military disturbances, nuclear or natural catastrophes or acts of God, and interruptions, loss or malfunctions of utilities, communications or computer (software and hardware) services; it being understood that the Trustee shall use reasonable efforts which are consistent with accepted practices in the banking industry to resume performance as soon as practicable under the circumstances;

(i) In no event shall the Trustee be responsible or liable for special, punitive, indirect, or consequential loss or damage of any kind whatsoever (including, but not limited to, loss of profit) irrespective of whether the Trustee has been advised of the likelihood of such loss or damage and regardless of the form of action;

(j) The permissive rights of the Trustee enumerated herein shall not be construed as duties;

(k) The Trustee may request that the Company deliver a certificate setting forth the names of individuals and/or titles of officers authorized at such time to take specified actions pursuant to this Indenture; and

(l) The Trustee shall not be required to give any bond or surety in respect of the performance of its powers and duties hereunder.

In addition, the Trustee shall not be deemed to have knowledge of any Default or Event of Default until a Responsible Officer of the Trustee shall have received written notification in the manner set forth in this Indenture, and such notice references the Securities and this Indenture or a Responsible Officer of the Trustee shall have obtained actual knowledge.

Section 7.03 Trustee Not Responsible for Recitals or Issuance or Securities .

(a) The recitals contained herein and in the Securities shall be taken as the statements of the Company, and the Trustee assumes no responsibility for the correctness of the same.

(b) The Trustee makes no representations as to the validity or sufficiency of this Indenture or of the Securities.

(c) The Trustee shall not be accountable for the use or application by the Company of any of the Securities or of the proceeds of such Securities, or for the use or

application of any moneys paid over by the Trustee in accordance with any provision of this Indenture or established pursuant to Section 2.01 , or for the use or application of any moneys received by any paying agent other than the Trustee.

Section 7.04 May Hold Securities .

The Trustee or any paying agent or Security Registrar, in its individual or any other capacity, may become the owner or pledgee of Securities with the same rights it would have if it were not Trustee, paying agent or Security Registrar.

Section 7.05 Moneys Held in Trust .

Subject to the provisions of Section 11.05 , all moneys received by the Trustee shall, until used or applied as herein provided, be held in trust for the purposes for which they were received, but need not be segregated from other funds except to the extent required by law. The Trustee shall be under no liability for interest on any moneys received by it hereunder except such as it may agree in writing with the Company to pay thereon.

Section 7.06 Compensation and Reimbursement .

(a) The Company covenants and agrees to pay to the Trustee, and the Trustee shall be entitled to, such compensation (which shall not be limited by any provision of law in regard to the compensation of a trustee of an express trust) as the Company and the Trustee may from time to time agree in writing, for all services rendered by it in the execution of the trusts hereby created and in the exercise and performance of any of the powers and duties hereunder of the Trustee, and, except as otherwise expressly provided herein, the Company will pay or reimburse the Trustee upon its request for all reasonable and documented expenses, disbursements and advances incurred or made by the Trustee in accordance with any of the provisions of this Indenture (including the reasonable and documented fees and the expenses and disbursements of its counsel and of all Persons not regularly in its employ), except any such expense, disbursement or advance as may arise from its negligence or willful misconduct. The Company also covenants to indemnify the Trustee (and its officers, agents, directors and employees) for, and to hold it harmless against, any documented loss, liability or expense, including reasonable and documented attorneys’ fees, incurred without negligence or willful misconduct on the part of the Trustee and arising out of or in connection with the acceptance or administration of this trust, including the reasonable and documented costs and expenses of defending itself against any claim of liability in the premises (whether asserted by the Company, or any holder or any other Person) or liability in connection with the exercise or performance of any of its powers or duties hereunder, or in connection with enforcing the provisions of this Section.

(b) The obligations of the Company under this Section to compensate and indemnify the Trustee and to pay or reimburse the Trustee for reasonable expenses, disbursements and advances shall constitute additional indebtedness hereunder. Such additional indebtedness shall be secured by a lien prior to that of the Securities upon all property and funds held or collected by the Trustee as such, except funds held in trust for the benefit of the holders of particular Securities.

(c) To ensure the Company’s payment obligations in this Section, the Trustee shall have a lien prior to the Securities on all funds or property held or collected by the Trustee, except that held in trust to pay principal of, premium, if any, or interest on particular Securities. When the Trustee incurs expenses or renders services in connection with an Event of Default specified in Section 6.01(a)(4) or (5) , the expenses (including the reasonable fees and expenses of its counsel) and the compensation for services in connection therewith are to constitute expenses of administration under any Bankruptcy Law. The provisions of this Section 7.06 shall survive the termination of this Indenture and the earlier resignation or removal of the Trustee.

Section 7.07 Reliance on Officer’s Certificate or Opinion of Counsel .

Except as otherwise provided in Section 7.01 , whenever in the administration of the provisions of this Indenture the Trustee shall deem it reasonably necessary or desirable that a matter be proved or established prior to taking or suffering or omitting to take any action hereunder, such matter (unless other evidence in respect thereof be herein specifically prescribed) may, in the absence of negligence or willful misconduct on the part of the Trustee, be deemed to be conclusively proved and established by an Officer’s Certificate and Opinion of Counsel delivered to the Trustee and such certificate and opinion, in the absence of negligence or willful misconduct on the part of the Trustee, shall be full warrant to the Trustee for any action taken, suffered or omitted to be taken by it under the provisions of this Indenture upon the faith thereof.

Section 7.08 Disqualification; Conflicting Interests .

If the Trustee has or shall acquire any “conflicting interest” within the meaning of Section 310(b) of the Trust Indenture Act, the Trustee and the Company shall in all respects comply with the provisions of Section 310(b) of the Trust Indenture Act.

Section 7.09 Corporate Trustee Required; Eligibility .

There shall at all times be a Trustee with respect to the Securities issued hereunder which shall at all times be a corporation organized and doing business under the laws of the United States of America or any state or territory thereof or of the District of Columbia, or a corporation or other Person permitted to act as trustee by the Commission, authorized under such laws to exercise corporate trust powers, having a combined capital and surplus of at least fifty million U.S. dollars ($50,000,000), and subject to supervision or examination by federal, state, territorial, or District of Columbia authority.

If such corporation or other Person publishes reports of condition at least annually, pursuant to law or to the requirements of the aforesaid supervising or examining authority, then for the purposes of this Section, the combined capital and surplus of such corporation or other Person shall be deemed to be its combined capital and surplus as set forth in its most recent report of condition so published. The Company may not, nor may any Person directly or indirectly controlling, controlled by, or under common control with the Company, serve as Trustee. In case at any time the Trustee shall cease to be eligible in accordance with the provisions of this Section, the Trustee shall resign immediately in the manner and with the effect specified in Section 7.10 .

Section 7.10 Resignation and Removal; Appointment of Successor .

(a) The Trustee or any successor hereafter appointed may at any time resign with respect to the Securities of one or more series by giving written notice thereof to the Company and by transmitting notice of resignation by electronic mail, or by first class postage prepaid mail, to the Securityholders of such series, as their names and addresses appear upon the Security Register. Upon receiving such notice of resignation, the Company shall promptly appoint a successor trustee with respect to Securities of such series by written instrument, in duplicate, executed by order of the Board of Directors, one copy of which instrument shall be delivered to the resigning Trustee and one copy to the successor trustee. If no successor trustee shall have been so appointed and have accepted appointment within 30 days after the mailing of such notice of resignation, the resigning Trustee may petition any court of competent jurisdiction for the appointment of a successor trustee with respect to Securities of such series, or any Securityholder of that series who has been a bona fide holder of a Security or Securities for at least six months may on behalf of himself and all others similarly situated, petition any such court for the appointment of a successor trustee. Such court may thereupon after such notice, if any, as it may deem proper and prescribe, appoint a successor trustee.

(b) In case at any time any one of the following shall occur:

(i) the Trustee shall fail to comply with the provisions of Section 7.08 after written request therefor by the Company or by any Securityholder who has been a bona fide holder of a Security or Securities for at least six months; or

(ii) the Trustee shall cease to be eligible in accordance with the provisions of Section 7.09 and shall fail to resign after written request therefor by the Company or by any such Securityholder; or

(iii) the Trustee shall become incapable of acting, or shall be adjudged a bankrupt or insolvent, or commence a voluntary bankruptcy proceeding, or a receiver of the Trustee or of its property shall be appointed or consented to, or any public officer shall take charge or control of the Trustee or of its property or affairs for the purpose of rehabilitation, conservation or liquidation;

then, in any such case, the Company may remove the Trustee with respect to all Securities and appoint a successor trustee by written instrument, in duplicate, executed by order of the Board of Directors, one copy of which instrument shall be delivered to the Trustee so removed and one copy to the successor trustee, or any Securityholder who has been a bona fide holder of a Security or Securities for at least six months may, on behalf of that holder and all others similarly situated, petition any court of competent jurisdiction for the removal of the Trustee and the appointment of a successor trustee. Such court may thereupon after such notice, if any, as it may deem proper and prescribe, remove the Trustee and appoint a successor trustee.

(c) The holders of a majority in aggregate principal amount of the Securities of any series at the time Outstanding may at any time remove the Trustee with respect to such series by so notifying the Trustee and the Company and may appoint a successor Trustee for such series with the consent of the Company.

(d) Any resignation or removal of the Trustee and appointment of a successor trustee with respect to the Securities of a series pursuant to any of the provisions of this Section shall become effective upon acceptance of appointment by the successor trustee as provided in Section 7.11 .

(e) Any successor trustee appointed pursuant to this Section may be appointed with respect to the Securities of one or more series or all of such series, and at any time there shall be only one Trustee with respect to the Securities of any particular series.

Section 7.11 Acceptance of Appointment By Successor .

(a) In case of the appointment hereunder of a successor trustee with respect to all Securities, every such successor trustee so appointed shall execute, acknowledge and deliver to the Company and to the retiring Trustee an instrument accepting such appointment, and thereupon the resignation or removal of the retiring Trustee shall become effective and such successor trustee, without any further act, deed or conveyance, shall become vested with all the rights, powers, trusts and duties of the retiring Trustee; but, on the request of the Company or the successor trustee, such retiring Trustee shall, upon full payment of any amount then due it pursuant to Section 7.06 , execute and deliver an instrument transferring to such successor trustee all the rights, powers, and trusts of the retiring Trustee and shall duly assign, transfer and deliver to such successor trustee all property and money held by such retiring Trustee hereunder.

(b) In case of the appointment hereunder of a successor trustee with respect to the Securities of one or more (but not all) series, the Company, the retiring Trustee and each successor trustee with respect to the Securities of one or more series shall execute and deliver an indenture supplemental hereto wherein each successor trustee shall accept such appointment and which (i) shall contain such provisions as shall be necessary or desirable to transfer and confirm to, and to vest in, each successor trustee all the rights, powers, trusts and duties of the retiring Trustee with respect to the Securities of that or those series to which the appointment of such successor trustee relates, (ii) shall contain such provisions as shall be deemed necessary or desirable to confirm that all the rights, powers, trusts and duties of the retiring Trustee with respect to the Securities of that or those series as to which the retiring Trustee is not retiring shall continue to be vested in the retiring Trustee, and (iii) shall add to or change any of the provisions of this Indenture as shall be necessary to provide for or facilitate the administration of the trusts hereunder by more than one Trustee, it being understood that nothing herein or in such supplemental indenture shall constitute such Trustees co-trustees of the same trust, that each such Trustee shall be trustee of a trust or trusts hereunder separate and apart from any trust or trusts hereunder administered by any other such Trustee and that no Trustee shall be responsible for any act or failure to act on the part of any other Trustee hereunder; and upon the execution and delivery of such supplemental indenture the resignation or removal of the retiring Trustee shall become effective to the extent provided therein, such retiring Trustee shall with respect to the Securities of that or those series to which the appointment of such successor trustee relates have no further responsibility for the exercise of rights and powers or for the performance of the duties and obligations vested in the Trustee under this Indenture, and each such successor trustee, without any further act, deed or conveyance, shall become vested with all the rights, powers, trusts and duties of the retiring Trustee with respect to the Securities of that or those series to which the appointment of such successor trustee relates; but, on request of the Company or any

successor trustee, such retiring Trustee shall duly assign, transfer and deliver to such successor trustee, to the extent contemplated by such supplemental indenture, the property and money held by such retiring Trustee hereunder with respect to the Securities of that or those series to which the appointment of such successor trustee relates.

(c) Upon request of any such successor trustee, the Company shall execute any and all instruments for more fully and certainly vesting in and confirming to such successor trustee all such rights, powers and trusts referred to in paragraph (a) or (b) of this Section, as the case may be.

(d) No successor trustee shall accept its appointment unless at the time of such acceptance such successor trustee shall be qualified and eligible under this Article.

(e) Upon acceptance of appointment by a successor trustee as provided in this Section, the Company shall transmit notice of the succession of such trustee hereunder by mail, first class postage prepaid, to the Securityholders, as their names and addresses appear upon the Security Register. If the Company fails to transmit such notice within ten days after acceptance of appointment by the successor trustee, the successor trustee shall cause such notice to be transmitted at the expense of the Company.

Section 7.12 Merger, Conversion, Consolidation or Succession to Business .

Any corporation into which the Trustee may be merged or converted or with which it may be consolidated, or any corporation resulting from any merger, conversion or consolidation to which the Trustee shall be a party, or any corporation succeeding to the corporate trust business of the Trustee, including the administration of the trust created by this Indenture, shall be the successor of the Trustee hereunder, provided that such corporation shall be qualified under the provisions of Section 7.08 and eligible under the provisions of Section 7.09 , without the execution or filing of any paper or any further act on the part of any of the parties hereto, anything herein to the contrary notwithstanding. In case any Securities shall have been authenticated, but not delivered, by the Trustee then in office, any successor by merger, conversion or consolidation to such authenticating Trustee may adopt such authentication and deliver the Securities so authenticated with the same effect as if such successor Trustee had itself authenticated such Securities.

Section 7.13 Preferential Collection of Claims Against the Company .

The Trustee shall comply with Section 311(a) of the Trust Indenture Act, excluding any creditor relationship described in Section 311(b) of the Trust Indenture Act. A Trustee who has resigned or been removed shall be subject to Section 311(a) of the Trust Indenture Act to the extent included therein.

Section 7.14 Notice of Default .

to a Responsible Officer of the Trustee or written notice of it is received by the Trustee, unless such Event of Default has been cured; provided , however , that, except in the case of a default in the payment of the principal of (or premium, if any) or interest on any Security, the Trustee shall be protected in withholding such notice if and so long as it in good faith determines that the withholding of such notice is in the interest of the Securityholders.

ARTICLE 8
CONCERNING THE SECURITYHOLDERS

Section 8.01 Evidence of Action by Securityholders .

Whenever in this Indenture it is provided that the holders of a majority or specified percentage in aggregate principal amount of the Securities of a particular series may take any action (including the making of any demand or request, the giving of any notice, consent or waiver or the taking of any other action), the fact that at the time of taking any such action the holders of such majority or specified percentage of that series have joined therein may be evidenced by any instrument or any number of instruments of similar tenor executed by such holders of Securities of that series in person or by agent or proxy appointed in writing.

If the Company shall solicit from the Securityholders of any series any request, demand, authorization, direction, notice, consent, waiver or other action, the Company may, at its option, as evidenced by an Officer’s Certificate, fix in advance a record date for such series for the determination of Securityholders entitled to give such request, demand, authorization, direction, notice, consent, waiver or other action, but the Company shall have no obligation to do so. If such a record date is fixed, such request, demand, authorization, direction, notice, consent, waiver or other action may be given before or after the record date, but only the Securityholders of record at the close of business on the record date shall be deemed to be Securityholders for the purposes of determining whether Securityholders of the requisite proportion of Outstanding Securities of that series have authorized or agreed or consented to such request, demand, authorization, direction, notice, consent, waiver or other action, and for that purpose the Outstanding Securities of that series shall be computed as of the record date; provided , however , that no such authorization, agreement or consent by such Securityholders on the record date shall be deemed effective unless it shall become effective pursuant to the provisions of this Indenture not later than six months after the record date.

Section 8.02 Proof of Execution by Securityholders .

Subject to the provisions of Section 7.01 , proof of the execution of any instrument by a Securityholder (such proof will not require notarization) or his agent or proxy and proof of the holding by any Person of any of the Securities shall be sufficient if made in the following manner:

(a) The fact and date of the execution by any such Person of any instrument may be proved in any reasonable manner acceptable to the Trustee.

(b) The ownership of Securities shall be proved by the Security Register of such Securities or by a certificate of the Security Registrar thereof. The Trustee may require such additional proof of any matter referred to in this Section as it shall deem necessary.

Section 8.03 Who May be Deemed Owners .

Prior to the due presentment for registration of transfer of any Security, the Company, the Trustee, any paying agent and any Security Registrar may deem and treat the Person in whose name such Security shall be registered upon the books of the Security Registrar as the absolute owner of such Security (whether or not such Security shall be overdue and notwithstanding any notice of ownership or writing thereon made by anyone other than the Security Registrar) for the purpose of receiving payment of or on account of the principal of, premium, if any, and (subject to Section 2.03 ) interest on such Security and for all other purposes; and neither the Company nor the Trustee nor any paying agent nor any Security Registrar shall be affected by any notice to the contrary.

Section 8.04 Certain Securities Owned by Company Disregarded .

In determining whether the holders of the requisite aggregate principal amount of Securities of a particular series have concurred in any direction, consent, demand, authorization, notice or waiver under this Indenture, the Securities of that series that are owned by the Company or any other obligor on the Securities of that series or by any Person directly or indirectly controlling or controlled by or under common control with the Company or any other obligor on the Securities of that series shall be disregarded and deemed not to be Outstanding for the purpose of any such determination, except that for the purpose of determining whether the Trustee shall be protected in relying on any such direction, consent or waiver, only Securities of such series that a Responsible Officer of the Trustee actually knows are so owned shall be so disregarded. The Securities so owned that have been pledged in good faith may be regarded as Outstanding for the purposes of this Section, if the pledgee shall establish to the satisfaction of the Trustee the pledgee’s right so to act with respect to such Securities and that the pledgee is not a Person directly or indirectly controlling or controlled by or under direct or indirect common control with the Company or any such other obligor. In case of a dispute as to such right, any decision by the Trustee taken upon the advice of counsel shall be full protection to the Trustee.

Section 8.05 Actions Binding on Future Securityholders .

At any time prior to (but not after) the evidencing to the Trustee, as provided in Section 8.01 , of the taking of any action by the holders of the majority or percentage in aggregate principal amount of the Securities of a particular series specified in this Indenture in connection with such action, any holder of a Security of that series that is shown by the evidence to be included in the Securities the holders of which have consented to such action may, by filing written notice with the Trustee, and upon proof of holding as provided in Section 8.02 , revoke such action so far as concerns such Security. Except as aforesaid any such action taken by the holder of any Security shall be conclusive and binding upon such holder and upon all future holders and owners of such Security, and of any Security issued in exchange therefor, on registration of transfer thereof or in place thereof, irrespective of whether or not any notation in regard thereto is made upon such Security. Any action taken by the holders of the majority or percentage in aggregate principal amount of the Securities of a particular series specified in this Indenture in connection with such action shall be conclusively binding upon the Company, the Trustee and the holders of all the Securities of that series.

ARTICLE 9
SUPPLEMENTAL INDENTURES

Section 9.01 Supplemental Indentures Without the Consent of Securityholders .

In addition to any supplemental indenture otherwise authorized by this Indenture, the Company and the Trustee may from time to time and at any time enter into an indenture or indentures supplemental hereto (which shall conform to the provisions of the Trust Indenture Act as then in effect), without the consent of the Securityholders at any time Outstanding, for one or more of the following purposes:

(a) to cure any ambiguity, defect, or inconsistency herein or in the Securities of any series;

(b) to comply with Article 10 ;

(d) to add to the covenants, restrictions, conditions or provisions relating to the Company for the benefit of the holders of all or any series of Securities (and if such covenants, restrictions, conditions or provisions are to be for the benefit of less than all series of Securities, stating that such covenants, restrictions, conditions or provisions are expressly being included solely for the benefit of such series), to make the occurrence, or the occurrence and the continuance, of a default in any such additional covenants, restrictions, conditions or provisions an Event of Default, or to surrender any right or power herein conferred upon the Company;

(e) to add to, delete from, or revise the conditions, limitations, and restrictions on the authorized amount, terms, or purposes of issue, authentication, and delivery of Securities, as herein set forth;

(f) to make any change that does not adversely affect the rights of any Securityholder in any material respect;

(g) to provide for the issuance of and establish the form and terms and conditions of the Securities of any series as provided in Section 2.01 , to establish the form of any certifications required to be furnished pursuant to the terms of this Indenture or any series of Securities, or to add to the rights of the holders of any series of Securities;

(h) to evidence and provide for the acceptance of appointment hereunder by a successor trustee or to appoint a separate trustee with respect to any series; or

(i) to comply with any requirements of the Commission or any successor in connection with the qualification of this Indenture under the Trust Indenture Act.

supplemental indenture that affects the Trustee’s own rights, duties or immunities under this Indenture or otherwise.

Any supplemental indenture authorized by the provisions of this Section may be executed by the Company and the Trustee without the consent of the holders of any of the Securities at the time Outstanding, notwithstanding any of the provisions of Section 9.02 .

Section 9.02 Supplemental Indentures With Consent of Securityholders .

With the consent (evidenced as provided in Section 8.01 ) of the holders of not less than a majority in aggregate principal amount of the Securities of each series affected by such supplemental indenture or indentures at the time Outstanding, the Company, when authorized by a Board Resolution, and the Trustee may from time to time and at any time enter into an indenture or indentures supplemental hereto (which shall conform to the provisions of the Trust Indenture Act as then in effect) for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of this Indenture or of any supplemental indenture or of modifying in any manner not covered by Section 9.01 the rights of the holders of the Securities of such series under this Indenture; provided , however , that no such supplemental indenture shall, without the consent of the holders of each Security then Outstanding and affected thereby, (a) extend the fixed maturity of any Securities of any series, or reduce the principal amount thereof, or reduce the rate or extend the time of payment of interest thereon, or reduce any premium payable upon the redemption thereof or (b) reduce the aforesaid percentage of Securities, the holders of which are required to consent to any such supplemental indenture.

It shall not be necessary for the consent of the Securityholders of any series affected thereby under this Section to approve the particular form of any proposed supplemental indenture, but it shall be sufficient if such consent shall approve the substance thereof. The Trustee shall not be obligated to enter into any such supplemental indenture that affects the Trustee’s own rights, duties or immunities under this Indenture or otherwise.

Section 9.03 Effect of Supplemental Indentures .

Upon the execution of any supplemental indenture pursuant to the provisions of this Article or of Section 10.01 , this Indenture shall, with respect to such series only, be and be deemed to be modified and amended in accordance therewith and the respective rights, limitations of rights, obligations, duties and immunities under this Indenture of the Trustee, the Company and the holders of Securities of the series affected thereby shall thereafter be determined, exercised and enforced hereunder subject in all respects to such modifications and amendments, and all the terms and conditions of any such supplemental indenture shall be and be deemed to be part of the terms and conditions of this Indenture for any and all purposes with respect to such series.

Section 9.04 Securities Affected by Supplemental Indentures .

matter provided for in such supplemental indenture. If the Company shall so determine, new Securities of that series so modified as to conform, in the opinion of the Board of Directors, to any modification of this Indenture contained in any such supplemental indenture may be prepared by the Company, authenticated by the Trustee and delivered in exchange for the Securities of that series then Outstanding.

Section 9.05 Execution of Supplemental Indentures .

Upon the request of the Company, accompanied by its Board Resolutions authorizing the execution of any such supplemental indenture, and upon the filing with the Trustee of evidence of the consent of Securityholders required to consent thereto as aforesaid, the Trustee shall join with the Company in the execution of such supplemental indenture unless such supplemental indenture affects the Trustee’s own rights, duties or immunities under this Indenture or otherwise, in which case the Trustee may in its discretion but shall not be obligated to enter into such supplemental indenture. The Trustee shall receive an Officer’s Certificate and an Opinion of Counsel as conclusive evidence that any supplemental indenture executed pursuant to this Article is authorized or permitted by the terms of this Article and that all conditions precedent to the execution of the supplemental indenture have been complied with and with respect to such Opinion of Counsel, that such supplemental indenture is the legal, valid and binding obligation of the Company, enforceable against each of them in accordance with its terms, subject to customary exceptions and qualifications.

Promptly after the execution by the Company and the Trustee of any supplemental indenture pursuant to the provisions of this Article, the Company shall transmit by electronic mail, or by first class mail, postage prepaid, a notice, setting forth in general terms the substance of such supplemental indenture, to the Securityholders of all series affected thereby as their names and addresses appear upon the Security Register. Any failure of the Company to mail, or cause the mailing of, such notice, or any defect therein, shall not, however, in any way impair or affect the validity of any such supplemental indenture.

ARTICLE 10
SUCCESSOR ENTITY

Section 10.01 Company May Consolidate, Etc .

Nothing contained in this Indenture shall prevent any consolidation or merger of the Company with or into any other Person (whether or not affiliated with the Company) or successive consolidations or mergers in which the Company or its successor or successors shall be a party or parties, or shall prevent any sale, conveyance, transfer or other disposition of the property of the Company or its successor or successors as an entirety, or substantially as an entirety, to any other corporation (whether or not affiliated with the Company or its successor or successors) authorized to acquire and operate the same; provided , however , (a) the Company hereby covenants and agrees that, upon any such consolidation or merger (in each case, if the Company is not the survivor of such transaction), sale, conveyance, transfer or other disposition, the due and punctual payment of the principal of (premium, if any) and interest on all of the Securities of all series in accordance with the terms of each series, according to their tenor, and the due and punctual performance and observance of all the covenants and conditions of this

Indenture with respect to each series or established with respect to such series pursuant to Section 2.01 to be kept or performed by the Company shall be expressly assumed, by supplemental indenture (which shall conform to the provisions of the Trust Indenture Act, as then in effect) executed and delivered to the Trustee by the entity formed by such consolidation, or into which the Company shall have been merged, or by the entity which shall have acquired such property and (b) in the event that the Securities of any series then Outstanding are convertible into or exchangeable for shares of common stock or other securities of the Company, such entity shall, by such supplemental indenture, make provision so that the Securityholders of Securities of that series shall thereafter be entitled to receive upon conversion or exchange of such Securities the number of securities or property to which a holder of the number of shares of common stock or other securities of the Company deliverable upon conversion or exchange of those Securities would have been entitled had such conversion or exchange occurred immediately prior to such consolidation, merger, sale, conveyance, transfer or other disposition. If the Company is not the surviving entity of any such transaction, the Company or the continuing entity agrees to deliver to the Trustee an Officer’s Certificate and Opinion of Counsel stating that the transaction and the supplemental indenture complies with this Section 10.01 and that all conditions precedent herein relating to the transaction have been satisfied.

Section 10.02 Successor Entity Substituted .

(a) In case of any such consolidation, merger, sale, conveyance, transfer or other disposition and upon the assumption by the successor entity by supplemental indenture, executed and delivered to the Trustee, of the obligations set forth under Section 10.01 on all of the Securities of all series Outstanding, such successor entity shall succeed to and be substituted for the Company with the same effect as if it had been named as the Company herein, and thereupon the predecessor corporation shall be relieved of all obligations and covenants under this Indenture and the Securities.

(b) In case of any such consolidation, merger, sale, conveyance, transfer or other disposition, such changes in phraseology and form (but not in substance) may be made in the Securities thereafter to be issued as may be appropriate.

(c) Nothing contained in this Article shall require any action by the Company in the case of a consolidation or merger of any Person into the Company where the Company is the survivor of such transaction, or the acquisition by the Company, by purchase or otherwise, of all or any part of the property of any other Person (whether or not affiliated with the Company).

ARTICLE 11
SATISFACTION AND DISCHARGE

Section 11.01 Satisfaction and Discharge of Indenture .

trust by the Company and thereupon repaid to the Company or discharged from such trust, as provided in Section 11.05 ); or (b) all such Securities of a particular series not theretofore delivered to the Trustee for cancellation shall have become due and payable, or are by their terms to become due and payable within one year or are to be called for redemption within one year under arrangements satisfactory to the Trustee for the giving of notice of redemption, and the Company shall deposit or cause to be deposited with the Trustee as trust funds the entire amount in moneys or Governmental Obligations or a combination thereof, sufficient in the opinion of a nationally recognized firm of independent public accountants expressed in a written certification thereof delivered to the Trustee, to pay at maturity or upon redemption all Securities of that series not theretofore delivered to the Trustee for cancellation, including principal (and premium, if any) and interest due or to become due to such date of maturity or date fixed for redemption, as the case may be, and if the Company shall also pay or cause to be paid all other sums payable hereunder with respect to such series by the Company then this Indenture shall thereupon cease to be of further effect with respect to such series except for the provisions of Sections 2.03 , 2.05 , 2.07 , 4.01 , 4.02 , 4.03 and 7.10 , that shall survive until the date of maturity or redemption date, as the case may be, and Sections 7.06 and 11.05 , that shall survive to such date and thereafter, and the Trustee, on demand of the Company and at the cost and expense of the Company shall execute such instruments reasonably requested by the Company acknowledging satisfaction of and discharging this Indenture with respect to such series.

Section 11.02 Discharge of Obligations .

If at any time all such Securities of a particular series not heretofore delivered to the Trustee for cancellation or that have not become due and payable as described in Section 11.01 shall have been paid by the Company by depositing irrevocably with the Trustee as trust funds moneys or an amount of Governmental Obligations sufficient to pay at maturity or upon redemption all such Securities of that series not theretofore delivered to the Trustee for cancellation, including principal (and premium, if any) and interest due or to become due to such date of maturity or date fixed for redemption, as the case may be, and if the Company shall also pay or cause to be paid all other sums payable hereunder by the Company with respect to such series, then after the date such moneys or Governmental Obligations, as the case may be, are deposited with the Trustee the obligations of the Company under this Indenture with respect to such series shall cease to be of further effect except for the provisions of Sections 2.03 , 2.05 , 2.07 , 4.01 , 4.02 , 4.03 , 7.06 , 7.10 and 11.05 hereof that shall survive until such Securities shall mature and be paid.

Thereafter, Sections 7.06 and 11.05 shall survive.

Section 11.03 Deposited Moneys to be Held in Trust .

All moneys or Governmental Obligations deposited with the Trustee pursuant to Sections 11.01 or 11.02 shall be held in trust and shall be available for payment as due, either directly or through any paying agent (including the Company acting as its own paying agent), to the holders of the particular series of Securities for the payment or redemption of which such moneys or Governmental Obligations have been deposited with the Trustee.

Section 11.04 Payment of Moneys Held by Paying Agents .

In connection with the satisfaction and discharge of this Indenture all moneys or Governmental Obligations then held by any paying agent under the provisions of this Indenture shall, upon demand of the Company, be paid to the Trustee and thereupon such paying agent shall be released from all further liability with respect to such moneys or Governmental Obligations.

Section 11.05 Repayment to Company .

Any moneys or Governmental Obligations deposited with any paying agent or the Trustee, or then held by the Company, in trust for payment of principal of or premium, if any, or interest on the Securities of a particular series that are not applied but remain unclaimed by the holders of such Securities for at least two years after the date upon which the principal of (and premium, if any) or interest on such Securities shall have respectively become due and payable, or such other shorter period set forth in applicable escheat or abandoned or unclaimed property law, shall be repaid to the Company on May 31 of each year or upon the Company’s request or (if then held by the Company) shall be discharged from such trust; and thereupon the paying agent and the Trustee shall be released from all further liability with respect to such moneys or Governmental Obligations, and the holder of any of the Securities entitled to receive such payment shall thereafter, as a general creditor, look only to the Company for the payment thereof.

ARTICLE 12
IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS AND DIRECTORS

Section 12.01 No Recourse .

No recourse under or upon any obligation, covenant or agreement of this Indenture, or of any Security, or for any claim based thereon or otherwise in respect thereof, shall be had against any incorporator, stockholder, officer or director, past, present or future as such, of the Company or of any predecessor or successor corporation, either directly or through the Company or any such predecessor or successor corporation, whether by virtue of any constitution, statute or rule of law, or by the enforcement of any assessment or penalty or otherwise; it being expressly understood that this Indenture and the obligations issued hereunder are solely corporate obligations, and that no such personal liability whatever shall attach to, or is or shall be incurred by, the incorporators, stockholders, officers or directors as such, of the Company or of any predecessor or successor corporation, or any of them, because of the creation of the indebtedness hereby authorized, or under or by reason of the obligations, covenants or agreements contained in this Indenture or in any of the Securities or implied therefrom; and that any and all such personal liability of every name and nature, either at common law or in equity or by constitution or statute, of, and any and all such rights and claims against, every such incorporator, stockholder, officer or director as such, because of the creation of the indebtedness hereby authorized, or under or by reason of the obligations, covenants or agreements contained in this Indenture or in any of the Securities or implied therefrom, are hereby expressly waived and released as a condition of, and as a consideration for, the execution of this Indenture and the issuance of such Securities.

ARTICLE 13
MISCELLANEOUS PROVISIONS

Section 13.01 Effect on Successors and Assigns .

All the covenants, stipulations, promises and agreements in this Indenture made by or on behalf of the Company shall bind its successors and assigns, whether so expressed or not.

Section 13.02 Actions by Successor .

Any act or proceeding by any provision of this Indenture authorized or required to be done or performed by any board, committee or officer of the Company shall and may be done and performed with like force and effect by the corresponding board, committee or officer of any corporation that shall at the time be the lawful successor of the Company.

Section 13.03 Surrender of Company Powers .

The Company by instrument in writing executed by authority of its Board of Directors and delivered to the Trustee may surrender any of the powers reserved to the Company, and thereupon such power so surrendered shall terminate both as to the Company and as to any successor corporation.

Section 13.04 Notices .

Except as otherwise expressly provided herein, any notice, request or demand that by any provision of this Indenture is required or permitted to be given, made or served by the Trustee or by the holders of Securities or by any other Person pursuant to this Indenture to or on the Company may be given or served by any standard form of telecommunication or by being deposited in first class mail, postage prepaid, addressed (until another address is filed in writing by the Company with the Trustee), as follows: [ ]. Any notice, election, request or demand by the Company or any Securityholder or by any other Person pursuant to this Indenture to or upon the Trustee shall be deemed to have been sufficiently given or made, for all purposes, if given or made in writing at the Corporate Trust Office of the Trustee. Notwithstanding anything herein to the contrary, where reference herein is made to notice of any event (including notice of redemption) to a Securityholder of Global Securities, whether by mail or otherwise, such notice shall be sufficiently given when delivered to the Depositary (or its designee) pursuant to the customary procedures of the Depositary.

Section 13.05 Governing Law; Jury Trial Waiver .

THIS INDENTURE AND EACH SECURITY, AND ANY CLAIM, CONTROVERSY OR DISPUTE ARISING UNDER OR RELATED TO THIS INDENTURE AND EACH SECURITY, SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK (WITHOUT REGARD TO THE CONFLICTS OF LAWS PROVISIONS THEREOF). EACH OF THE COMPANY AND THE TRUSTEE HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL

PROCEEDING ARISING OUT OF OR RELATING TO THIS INDENTURE, THE SECURITIES OR THE TRANSACTION CONTEMPLATED HEREBY.

Section 13.06 Treatment of Securities as Debt .

It is intended that the Securities will be treated as indebtedness and not as equity for federal income tax purposes. The provisions of this Indenture shall be interpreted to further this intention.

Section 13.07 Certificates and Opinions as to Conditions Precedent .

(a) Upon any application or demand by the Company to the Trustee to take any action under any of the provisions of this Indenture, the Company shall furnish to the Trustee an Officer’s Certificate stating that all covenants and conditions precedent provided for in this Indenture (other than the certificate to be delivered pursuant to Section 13.12 ) relating to the proposed action have been complied with and an Opinion of Counsel stating that in the opinion of such counsel all such covenants and conditions precedent have been complied with.

(b) Each certificate or opinion provided for in this Indenture and delivered to the Trustee with respect to compliance with a condition or covenant in this Indenture shall include (i) a statement that the Person making such certificate or opinion has read such covenant or condition; (ii) a brief statement as to the nature and scope of the examination or investigation upon which the statements or opinions contained in such certificate or opinion are based; (iii) a statement that, in the opinion of such Person, he has made such examination or investigation as is reasonably necessary to enable him to express an informed opinion as to whether or not such covenant or condition has been complied with; and (iv) a statement as to whether or not, in the opinion of such Person, such condition or covenant has been complied with.

Section 13.08 Payments on Business Days .

Except as provided pursuant to Section 2.01 pursuant to a Board Resolution, and set forth in an Officer’s Certificate, or established in one or more indentures supplemental to this Indenture, in any case where the date that principal of, interest and/or premium, if any, on any Security is due or otherwise payable shall not be a Business Day or is a day on which the banking institutions in the city of the office of the Paying Agent are authorized or obligated by law to close or be closed, then payment of principal, premium, if any, and/or interest may be made on the next succeeding day that is a Business Day and is not a day on which the banking institutions in the city of the office of the Paying Agent are authorized or obligated by law to close or be closed with the same force and effect as if made on the nominal date of maturity or redemption, and no interest shall accrue for the period after such nominal date.

Section 13.09 Conflict with Trust Indenture Act .

If and to the extent that any provision of this Indenture limits, qualifies or conflicts with the duties imposed by Sections 310 to 317, inclusive, of the Trust Indenture Act, such imposed duties shall control.

Section 13.10 Counterparts .

This Indenture may be executed in any number of counterparts, each of which shall be an original, but such counterparts shall together constitute but one and the same instrument. The exchange of copies of this Indenture and of signature pages by facsimile or PDF transmission shall constitute effective execution and delivery of this Indenture as to the parties hereto and may be used in lieu of the original Indenture for all purposes. Signatures of the parties hereto transmitted by facsimile or PDF shall be deemed to be their original signatures for all purposes.

Section 13.11 Separability .

In case any one or more of the provisions contained in this Indenture or in the Securities of any series shall for any reason be held to be invalid, illegal or unenforceable in any respect, such invalidity, illegality or unenforceability shall not affect any other provisions of this Indenture or of such Securities, but this Indenture and such Securities shall be construed as if such invalid or illegal or unenforceable provision had never been contained herein or therein.

Section 13.12 Compliance Certificates .

The Company shall deliver to the Trustee, within 120 days after the end of each fiscal year during which any Securities of any series were outstanding, an Officer’s Certificate stating whether or not the signers know of any Event of Default that occurred during such fiscal year. Such certificate shall contain a certification from the principal executive officer, principal financial officer or principal accounting officer of the Company that a review has been conducted of the activities of the Company and the Company’s performance under this Indenture and that the Company has complied with all conditions and covenants under this Indenture. For purposes of this Section 13.12 , such compliance shall be determined without regard to any period of grace or requirement of notice provided under this Indenture. If the officer of the Company signing such certificate has knowledge of such an Event of Default, the certificate shall describe any such Event of Default and its status.

Section 13.13 USA PATRIOT ACT .

The parties hereto acknowledge that in accordance with Section 326 of the USA PATRIOT Act, the Trustee, like all financial institutions and in order to help fight the funding of terrorism and money laundering, is required to obtain, verify, and record information that identifies each person or legal entity that establishes a relationship or opens an account with the Trustee. The parties to this Indenture agree that they will provide the Trustee with such information as it may request in order for the Trustee to satisfy the requirements of the USA PATRIOT Act.

Section 13.14 Calculations .

It is understood that the Trustee nor the Paying Agent shall have no responsibility for any calculations hereunder and shall be entitled to conclusively rely on the calculations of the Company without any independent verification or investigation.

IN WITNESS WHEREOF , the parties hereto have caused this Indenture to be duly executed all as of the day and year first above written.

	RUBIUS THERAPEUTICS, INC. , as Issuer


	By:

	Name:

	Title:


	[TRUSTEE] , as Trustee


	By:

	Name:

	Title:

Signature Page to Form of Indenture

TRUST INDENTURE ACT CROSS-REFERENCE TABLE(2)

Section of Trust Indenture Act of 1939, as amended		Section of Indenture
310(a)		7.09
310(b)		7.08 7.10
310(c)		Inapplicable
311(a)		7.13
311(b)		7.13
311(c)		Inapplicable
312(a)		5.01 5.02(a)
312(b)		5.02(c)
312(c)		5.02(c)
313(a)		5.04(a)
313(b)		5.04(b)
313(c)		5.04(a) 5.04(b)
313(d)		5.04(c)
314(a)		5.03 13.12
314(b)		Inapplicable
314(c)		13.07(a)
314(d)		Inapplicable
314(e)		13.07(b)
314(f)		Inapplicable
315(a)		7.01(a) 7.01(b)
315(b)		7.14
315(c)		7.01(a)
315(d)		7.01(b)
315(e)		6.07
316(a)		6.06 8.04
316(b)		6.04
316(c)		8.01
317(a)		6.02
317(b)		4.03
318(a)		13.09

(2) This Cross-Reference Table does not constitute part of the Indenture and shall not have any bearing on the interpretation of any of its terms or provisions.

Exhibit 4.4

RUBIUS THERAPEUTICS, INC.

Issuer

AND

[TRUSTEE],

Trustee

INDENTURE

Dated as of [ · ], 201[ · ]

Subordinated Debt Securities

TABLE OF CONTENTS(1)

ARTICLE 1 DEFINITIONS		1

Section 1.01	Definitions of Terms	1

ARTICLE 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES		5

Section 2.01	Designation and Terms of Securities	5
Section 2.02	Form of Securities and Trustee’s Certificate	8
Section 2.03	Denominations: Provisions for Payment	8
Section 2.04	Execution and Authentications	10
Section 2.05	Registration of Transfer and Exchange	11
Section 2.06	Temporary Securities	12
Section 2.07	Mutilated, Destroyed, Lost or Stolen Securities	12
Section 2.08	Cancellation	13
Section 2.09	Benefits of Indenture	13
Section 2.10	Authenticating Agent	14
Section 2.11	Global Securities	14

ARTICLE 3 REDEMPTION OF SECURITIES AND SINKING FUND PROVISIONS		15

Section 3.01	Redemption	15
Section 3.02	Notice of Redemption	16
Section 3.03	Payment Upon Redemption	17
Section 3.04	Sinking Fund	17
Section 3.05	Satisfaction of Sinking Fund Payments with Securities	17
Section 3.06	Redemption of Securities for Sinking Fund	18

ARTICLE 4 COVENANTS		18

Section 4.01	Payment of Principal, Premium and Interest	18
Section 4.02	Maintenance of Office or Agency	18
Section 4.03	Paying Agents	19
Section 4.04	Appointment to Fill Vacancy in Office of Trustee	20
Section 4.05	Compliance with Consolidation Provisions	20

ARTICLE 5 SECURITYHOLDERS’ LISTS AND REPORTS BY THE COMPANY AND THE TRUSTEE		20

Section 5.01	Company to Furnish Trustee Names and Addresses of Securityholders	20
Section 5.02	Preservation Of Information; Communications With Securityholders	21
Section 5.03	Reports by the Company	21
Section 5.04	Reports by the Trustee	21

ARTICLE 6 REMEDIES OF THE TRUSTEE AND SECURITYHOLDERS ON EVENT OF DEFAULT		22

Section 6.01	Events of Default	22
Section 6.02	Collection of Indebtedness and Suits for Enforcement by Trustee	24

(1) This Table of Contents does not constitute part of the Indenture and shall not have any bearing on the interpretation of any of its terms or provisions.

Section 6.03	Application of Moneys Collected	25
Section 6.04	Limitation on Suits	25
Section 6.05	Rights and Remedies Cumulative; Delay or Omission Not Waiver	26
Section 6.06	Control by Securityholders	27
Section 6.07	Undertaking to Pay Costs	27

ARTICLE 7 CONCERNING THE TRUSTEE		28

Section 7.01	Certain Duties and Responsibilities of Trustee	28
Section 7.02	Certain Rights of Trustee	29
Section 7.03	Trustee Not Responsible for Recitals or Issuance or Securities	30
Section 7.04	May Hold Securities	31
Section 7.05	Moneys Held in Trust	31
Section 7.06	Compensation and Reimbursement	31
Section 7.07	Reliance on Officer’s Certificate or Opinion of Counsel	32
Section 7.08	Disqualification; Conflicting Interests	32
Section 7.09	Corporate Trustee Required; Eligibility	32
Section 7.10	Resignation and Removal; Appointment of Successor	33
Section 7.11	Acceptance of Appointment By Successor	34
Section 7.12	Merger, Conversion, Consolidation or Succession to Business	35
Section 7.13	Preferential Collection of Claims Against the Company	35
Section 7.14	Notice of Default	36

ARTICLE 8 CONCERNING THE SECURITYHOLDERS		36

Section 8.01	Evidence of Action by Securityholders	36
Section 8.02	Proof of Execution by Securityholders	36
Section 8.03	Who May be Deemed Owners	37
Section 8.04	Certain Securities Owned by Company Disregarded	37
Section 8.05	Actions Binding on Future Securityholders	37

ARTICLE 9 SUPPLEMENTAL INDENTURES		38

Section 9.01	Supplemental Indentures Without the Consent of Securityholders	38
Section 9.02	Supplemental Indentures With Consent of Securityholders	39
Section 9.03	Effect of Supplemental Indentures	39
Section 9.04	Securities Affected by Supplemental Indentures	40
Section 9.05	Execution of Supplemental Indentures	40

ARTICLE 10 SUCCESSOR ENTITY		40

Section 10.01	Company May Consolidate, Etc.	40
Section 10.02	Successor Entity Substituted	41

ARTICLE 11 SATISFACTION AND DISCHARGE		42

Section 11.01	Satisfaction and Discharge of Indenture	42
Section 11.02	Discharge of Obligations	42
Section 11.03	Deposited Moneys to be Held in Trust	42
Section 11.04	Payment of Moneys Held by Paying Agents	43
Section 11.05	Repayment to Company	43

ARTICLE 12 IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS AND DIRECTORS		43

Section 12.01	No Recourse	43

ARTICLE 13 MISCELLANEOUS PROVISIONS		44

Section 13.01	Effect on Successors and Assigns	44
Section 13.02	Actions by Successor	44
Section 13.03	Surrender of Company Powers	44
Section 13.04	Notices	44
Section 13.05	Governing Law; Jury Trial Waiver	44
Section 13.06	Treatment of Securities as Debt	45
Section 13.07	Certificates and Opinions as to Conditions Precedent	45
Section 13.08	Payments on Business Days	45
Section 13.09	Conflict with Trust Indenture Act	46
Section 13.10	Counterparts	46
Section 13.11	Separability	46
Section 13.12	Compliance Certificates	46
Section 13.13	USA PATRIOT ACT	46
Section 13.14	Calculations	47

TRUST INDENTURE ACT CROSS-REFERENCE TABLE		A-1

iii

INDENTURE

INDENTURE , dated as of [ · ], 201 , among RUBIUS THERAPEUTICS, INC. , a Delaware corporation (the “ Company ”), and [ TRUSTEE ] as trustee (the “ Trustee ”):

WHEREAS , for its lawful corporate purposes, the Company has duly authorized the execution and delivery of this Indenture to provide for the issuance of subordinated debt securities (hereinafter referred to as the “ Securities ”), in an unlimited aggregate principal amount to be issued from time to time in one or more series as in this Indenture provided, as registered Securities without coupons, to be authenticated by the certificate of the Trustee;

WHEREAS , to provide the terms and conditions upon which the Securities are to be authenticated, issued and delivered, the Company has duly authorized the execution of this Indenture; and

WHEREAS , all things necessary to make this Indenture a valid and binding agreement of the Company, in accordance with its terms, have been done.

ARTICLE 1
DEFINITIONS

Section 1.01 Definitions of Terms .

“ Authenticating Agent ” means an authenticating agent with respect to all or any of the series of Securities appointed by the Trustee pursuant to Section 2.10 .

“ Bankruptcy Law ” means Title 11, U.S. Code, or any similar federal or state law for the relief of debtors.

“ Board of Directors ” means the Board of Directors (or the functional equivalent thereof) of the Company or any duly authorized committee of such Board.

“ Company ” means Rubius Therapeutics, Inc., a corporation duly organized and existing under the laws of the State of Delaware, and, subject to the provisions of Article 10 , shall also include its successors and assigns.

“ Company Order ” means a written order of the Company, signed by an Officer of the Company, and delivered to the Trustee.

“ Custodian ” means any receiver, trustee, assignee, liquidator or similar official under any Bankruptcy Law.

“ Defaulted Interest ” has the meaning set forth in Section 2.03 .

“ Event of Default ” means, with respect to Securities of a particular series, any event specified in Section 6.01 , continued for the period of time, if any, therein designated.

“ Exchange Act ” means the United States Securities and Exchange Act of 1934, as amended, and the rules and regulations promulgated by the Commission thereunder.

“ Securities ” has the meaning stated in the first recital of this Indenture and more particularly means any Securities authenticated and delivered under this Indenture.

“ Security Register ” and “ Security Registrar ” shall have the meanings as set forth in Section 2.05 .

“ Subsidiary ” means, with respect to any Person:

(2) a partnership in which such Person or a subsidiary of such Person is, at the date of determination, a general partner of such partnership; or

“ Trust Indenture Act ” means the Trust Indenture Act of 1939, as amended and in effect from time to time.

“ U.S. dollar ” or “ $ ” means the lawful currency of the United States of America.

ARTICLE 2
ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES

Section 2.01 Designation and Terms of Securities .

(1) the title of the Securities of the series (which shall distinguish the Securities of that series from all other Securities);

(3) the date or dates on which the principal of the Securities of the series is payable;

(5) the rate or rates at which the Securities of the series shall bear interest or the manner of calculation of such rate or rates, if any;

(7) the right, if any, to extend the interest payment periods and the duration of such extension;

(8) the period or periods within which, the price or prices at which and the terms and conditions upon which Securities of the series may be redeemed, converted or exchanged, in whole or in part;

(10) the form of the Securities of the series including the form of the Certificate of Authentication for such series;

(11) if other than minimum denominations of one thousand U.S. dollars ($1,000) or any integral multiple of $1,000 thereof, the denominations in which the Securities of the series shall be issuable;

(16) any additional or alternative Events of Default;

(20) whether interest will be payable in cash or additional Securities at the Company’s or the Securityholders’ option and the terms and conditions upon which the election may be made;

(21) the terms and conditions, if any, upon which the Company shall pay amounts in addition to the stated interest, premium, if any and principal amounts of

the Securities of the series to any Securityholder that is not a “United States person” for federal tax purposes;

(22) additional or alternative provisions, if any, related to defeasance and discharge of the offered Securities;

(23) the applicability of any guarantees;

(24) any restrictions on transfer, sale or assignment of the Securities of the series; and

(25) any other terms of the series.

All Securities of any one series shall be substantially identical except as may otherwise be provided in or pursuant to any such Board Resolution or in any indentures supplemental hereto.

Section 2.02 Form of Securities and Trustee’s Certificate .

Section 2.03 Denominations: Provisions for Payment .

Section 2.04 Execution and Authentications .

The Securities shall be signed on behalf of the Company by one of its Officers. Signatures may be in the form of a manual or facsimile signature.

valid and binding obligations against the Company, enforceable against it in accordance with its terms, subject to customary exceptions and qualifications.

Section 2.05 Registration of Transfer and Exchange .

(d) The Company shall not be required (i) to issue, exchange or register the transfer of any Securities during a period beginning at the opening of business 15 days before the

Neither the Trustee nor any Agent shall have any responsibility or liability for any actions taken or not taken by the Depositary.

Section 2.06 Temporary Securities .

Section 2.07 Mutilated, Destroyed, Lost or Stolen Securities .

Section 2.08 Cancellation .

Section 2.09 Benefits of Indenture .

Nothing in this Indenture or in the Securities, express or implied, shall give or be construed to give to any Person, other than the parties hereto and the holders of the

Securities (and, with respect to the provisions of Article 14 , the holders of any indebtedness of the Company to which the Securities of any series are subordinated) any legal or equitable right, remedy or claim under or in respect of this Indenture, or under any covenant, condition or provision herein contained; all such covenants, conditions and provisions being for the sole benefit of the parties hereto and of the holders of the Securities (and, with respect to the provisions of Article 14 , the holders of any indebtedness of the Company to which the Securities of any series are subordinated).

Section 2.10 Authenticating Agent .

Section 2.11 Global Securities .

may be transferred, in whole but not in part, only to another nominee of the Depositary or to a successor Depositary or to a nominee of such successor Depositary.”

(b) Notwithstanding the provisions of Section 2.05 , the Global Security of a series may be transferred, in whole but not in part and in the manner provided in Section 2.05 , only to another nominee of the Depositary for such series, or to a successor Depositary for such series selected or approved by the Company or to a nominee of such successor Depositary.

ARTICLE 3
REDEMPTION OF SECURITIES AND SINKING FUND PROVISIONS

Section 3.01 Redemption .

The Company may redeem the Securities of any series issued hereunder on and after the dates and in accordance with the terms established for such series pursuant to Section 2.01 hereof.

Section 3.02 Notice of Redemption .

(a) In case the Company shall desire to exercise such right to redeem all or, as the case may be, a portion of the Securities of any series in accordance with any right the Company reserved for itself to do so pursuant to Section 2.01 hereof, the Company shall, or shall cause the Trustee (upon 5 Business Days written notice, unless a shorter period shall be satisfactory to the Trustee) to, give notice of such redemption to holders of the Securities of such series to be redeemed by mailing, electronically or by first class postage prepaid mail, a notice of such redemption not less than 15 days and not more than 90 days, except that redemption notices may be sent more than 90 days prior to the redemption date if the notice is issued in connection with a defeasance of the Securities or a satisfaction and discharge, before the date fixed for redemption of that series to such holders (with a copy to the Trustee) at their last addresses as they shall appear upon the Security Register, unless a shorter period is specified in the Securities to be redeemed. Any notice that is mailed in the manner herein provided shall be conclusively presumed to have been duly given, whether or not the registered holder receives the notice. In any case, failure duly to give such notice to the holder of any Security of any series designated for redemption in whole or in part, or any defect in the notice, shall not affect the validity of the proceedings for the redemption of any other Securities of such series or any other series. In the case of any redemption of Securities prior to the expiration of any restriction on such redemption provided in the terms of such Securities or elsewhere in this Indenture, the Company shall furnish the Trustee with an Officer’s Certificate evidencing compliance with any such restriction.

notice of redemption in the manner set forth in this Section, such notice to be in the name and at the expense of the Company. In any case in which notice of redemption is to be sent by the Trustee or any such paying agent, the Company shall deliver or cause to be delivered to, or permit to remain with, the Trustee or such paying agent, as the case may be, such Security Register, transfer books or other records, or suitable copies or extracts therefrom, sufficient to enable the Trustee or such paying agent to give any notice by mail that may be required under the provisions of this Section.

Section 3.03 Payment Upon Redemption .

Section 3.04 Sinking Fund .

Section 3.05 Satisfaction of Sinking Fund Payments with Securities .

The Company (i) may deliver Outstanding Securities of a series and (ii) may apply as a credit Securities of a series that have been redeemed either at the election of the Company

pursuant to the terms of such Securities or through the application of permitted optional sinking fund payments pursuant to the terms of such Securities, in each case in satisfaction of all or any part of any sinking fund payment with respect to the Securities of such series required to be made pursuant to the terms of such Securities as provided for by the terms of such series, provided that such Securities have not been previously so credited. Such Securities shall be received and credited for such purpose by the Trustee at the redemption price specified in such Securities for redemption through operation of the sinking fund and the amount of such sinking fund payment shall be reduced accordingly.

Section 3.06 Redemption of Securities for Sinking Fund .

ARTICLE 4
COVENANTS

Section 4.01 Payment of Principal, Premium and Interest .

Section 4.02 Maintenance of Office or Agency .

So long as any series of the Securities remain Outstanding, the Company agrees to maintain an office or agency with respect to each such series and at such other location or

locations as may be designated as provided in this Section 4.02 , where (i) Securities of that series may be presented for payment, (ii) Securities of that series may be presented as herein above authorized for registration of transfer and exchange, and (iii) notices in respect of the Securities of that series and this Indenture may be given or made, such designation to continue with respect to such office or agency until the Company shall, by written notice in an Officer’s Certificate and delivered to the Trustee, designate some other office or agency for such purposes or any of them. If at any time the Company shall fail to maintain any such required office or agency or shall fail to furnish the Trustee with the address thereof, such presentations and notices may be made at the Corporate Trust Office of the Trustee, and the Company hereby appoints the Trustee as its agent to receive all such presentations and notices; provided, however, the Trustee shall not be considered an agent of the Company for service of process.

Section 4.03 Paying Agents .

(5) that it will perform all other duties of paying agent as set forth in this Indenture.

due date of the principal of (and premium, if any) or interest on any Securities of that series, deposit with the paying agent a sum sufficient to pay the principal (and premium, if any) or interest so becoming due, such sum to be held in trust for the benefit of the Persons entitled to such principal, premium or interest, and (unless such paying agent is the Trustee) the Company will promptly notify the Trustee of this action or failure so to act.

(d) The Company initially appoints the Trustee at its Corporate Trust Office as its paying agent with respect to the Securities.

Section 4.04 Appointment to Fill Vacancy in Office of Trustee .

Section 4.05 Compliance with Consolidation Provisions .

ARTICLE 5
SECURITYHOLDERS’ LISTS AND REPORTS BY THE COMPANY AND THE TRUSTEE

Section 5.01 Company to Furnish Trustee Names and Addresses of Securityholder s .

Section 5.02 Preservation Of Information; Communications With Securityholders .

(a) The Trustee shall preserve, in as current a form as is reasonably practicable, all information as to the names and addresses of the holders of Securities contained in the most recent list furnished to it as provided in Section 5.01 and as to the names and addresses of holders of Securities received by the Trustee in its capacity as Security Registrar (if acting in such capacity).

(b) The Trustee may destroy any list furnished to it as provided in Section 5.01 upon receipt of a new list so furnished.

Section 5.03 Reports by the Company .

Section 5.04 Reports by the Trustee .

(a) If required by Section 313(a) of the Trust Indenture Act, the Trustee, within sixty (60) days after each May 15, commencing the calendar year after the year in which

the first Securities are issued hereunder, shall transmit by mail, first class postage prepaid, to the Securityholders, as their names and addresses appear upon the Security Register, a brief report dated as of such May 15, which complies with Section 313(a) of the Trust Indenture Act.

(b) The Trustee shall comply with Section 313(b) and 313(c) of the Trust Indenture Act.

ARTICLE 6
REMEDIES OF THE TRUSTEE AND SECURITYHOLDERS ON EVENT OF DEFAULT

Section 6.01 Events of Default .

(a) Whenever used herein with respect to Securities of a particular series, “ Event of Default ” means any one or more of the following events that has occurred and is continuing:

(4) the Company pursuant to or within the meaning of any Bankruptcy Law (i) commences a voluntary case, (ii) consents to the entry of an order for relief against it in an involuntary case, (iii) consents to the appointment of a Custodian of it or for all or substantially all of its property or (iv) makes a general assignment for the benefit of its creditors; or

No such rescission and annulment shall extend to or shall affect any subsequent default or impair any right consequent thereon.

shall have been determined adversely to the Trustee, then and in every such case, subject to any determination in such proceedings, the Company and the Trustee shall be restored respectively to their former positions and rights hereunder, and all rights, remedies and powers of the Company and the Trustee shall continue as though no such proceedings had been taken.

Section 6.02 Collection of Indebtedness and Suits for Enforcement by Trustee .

other proceeding relative thereto, and any such suit or proceeding instituted by the Trustee shall be brought in its own name as trustee of an express trust, and any recovery of judgment shall, after provision for payment to the Trustee of any amounts due under Section 7.06 , be for the ratable benefit of the holders of the Securities of such series.

Section 6.03 Application of Moneys Collected .

FIRST : To the payment of all indebtedness of the Company to which such series of Securities is subordinated to the extent required by Section 7.06 and any subordination terms of the series specified as contemplated by Article 14 ;

THIRD : To the payment of the remainder, if any, to the Company or any other Person lawfully entitled thereto.

Section 6.04 Limitation on Suits .

less than 25% in aggregate principal amount of the Securities of such series then Outstanding shall have made written request upon the Trustee to institute such action, suit or proceeding in its own name as Trustee hereunder; (iii) such holder or holders shall have offered to the Trustee such indemnity reasonably satisfactory to it as it may require against the costs, expenses, claims and liabilities to be incurred therein or thereby; (iv) the Trustee for 90 days after its receipt of such notice, request and offer of indemnity, shall have failed to institute any such action, suit or proceeding and (v) during such 90 day period, the holders of a majority in principal amount of the Securities of that series do not give the Trustee a direction inconsistent with the request.

Section 6.05 Rights and Remedies Cumulative; Delay or Omission Not Waiver .

Section 6.06 Control by Securityholders .

The holders of a majority in aggregate principal amount of the Securities of any series at the time Outstanding, determined in accordance with Section 8.04 , shall have the right to direct the time, method and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred on the Trustee with respect to such series; provided , however , that such direction shall not be in conflict with any rule of law or with this Indenture or subject the Trustee in its sole discretion to personal liability. The Trustee shall have the right to decline to follow any such direction if the Trustee in good faith shall determine that the proceeding so directed, subject to the Trustee’s duties under the Trust Indenture Act, would involve the Trustee in personal liability or might be unduly prejudicial to the Securityholders not involved in the proceeding. Prior to taking any action under this Indenture, the Trustee shall be entitled to indemnity or security satisfactory to it against loss, liability or expense that may be caused by taking such action. The holders of a majority in aggregate principal amount of the Securities of any series at the time Outstanding affected thereby, determined in accordance with Section 8.04 , may on behalf of the holders of all of the Securities of such series waive any past default in the performance of any of the covenants contained herein or established pursuant to Section 2.01 with respect to such series and its consequences, except a default in the payment of the principal of, or premium, if any, or interest on, any of the Securities of that series as and when the same shall become due by the terms of such Securities otherwise than by acceleration (unless such default has been cured and a sum sufficient to pay all matured installments of interest and principal and any premium has been deposited with the Trustee (in accordance with Section 6.01(c) ). Upon any such waiver, the default covered thereby shall be deemed to be cured for all purposes of this Indenture and the Company, the Trustee and the holders of the Securities of such series shall be restored to their former positions and rights hereunder, respectively; but no such waiver shall extend to any subsequent or other default or impair any right consequent thereon.

Section 6.07 Undertaking to Pay Costs .

ARTICLE 7
CONCERNING THE TRUSTEE

Section 7.01 Certain Duties and Responsibilities of Trustee .

(a) The Trustee, prior to the occurrence of an Event of Default with respect to the Securities of a series and after the curing of all Events of Default with respect to the Securities of that series that may have occurred, shall undertake to perform with respect to the Securities of such series such duties and only such duties as are specifically set forth in this Indenture, and no implied covenants shall be read into this Indenture against the Trustee. In case an Event of Default with respect to the Securities of a series has occurred (that has not been cured or waived), the Trustee shall exercise with respect to Securities of that series such of the rights and powers vested in it by this Indenture, and use the same degree of care and skill in their exercise, as a prudent person would exercise or use under the circumstances in the conduct of such person’s own affairs.

(b) No provision of this Indenture shall be construed to relieve the Trustee from liability for its own negligent action, its own negligent failure to act, or its own willful misconduct, except that:

(4) none of the provisions contained in this Indenture shall require the Trustee to expend or risk its own funds or otherwise incur personal or financial liability in the performance of any of its duties or in the exercise of any of its rights or powers if there is reasonable ground for believing that the repayment of such funds or liability is not reasonably assured to it under the terms of this Indenture or adequate indemnity against such risk is not reasonably assured to it.

Section 7.02 Certain Rights of Trustee .

Except as otherwise provided in Section 7.01 :

the Trustee by the security afforded to it by the terms of this Indenture, the Trustee may require indemnity or security satisfactory to it against such costs, expenses, claims or liabilities as a condition to so proceeding. The reasonable expense of every such examination shall be paid by the Company or, if paid by the Trustee, shall be repaid by the Company upon demand;

(j) The permissive rights of the Trustee enumerated herein shall not be construed as duties;

(l) The Trustee shall not be required to give any bond or surety in respect of the performance of its powers and duties hereunder.

Section 7.03 Trustee Not Responsible for Recitals or Issuance or Securities .

(a) The recitals contained herein and in the Securities shall be taken as the statements of the Company, and the Trustee assumes no responsibility for the correctness of the same.

(b) The Trustee makes no representations as to the validity or sufficiency of this Indenture or of the Securities.

(c) The Trustee shall not be accountable for the use or application by the Company of any of the Securities or of the proceeds of such Securities, or for the use or application of any moneys paid over by the Trustee in accordance with any provision of this Indenture or established pursuant to Section 2.01 , or for the use or application of any moneys received by any paying agent other than the Trustee.

Section 7.04 May Hold Securities .

Section 7.05 Moneys Held in Trust .

Section 7.06 Compensation and Reimbursement .

(b) The obligations of the Company under this Section to compensate and indemnify the Trustee and to pay or reimburse the Trustee for reasonable expenses, disbursements and advances shall constitute indebtedness of the Company to which the Securities are subordinated. Such additional indebtedness shall be secured by a lien prior to that

of the Securities upon all property and funds held or collected by the Trustee as such, except funds held in trust for the benefit of the holders of particular Securities.

Section 7.07 Reliance on Officer’s Certificate or Opinion of Counsel .

Section 7.08 Disqualification; Conflicting Interests .

Section 7.09 Corporate Trustee Required; Eligibility .

provisions of this Section, the Trustee shall resign immediately in the manner and with the effect specified in Section 7.10 .

Section 7.10 Resignation and Removal; Appointment of Successor .

(b) In case at any time any one of the following shall occur:

(ii) the Trustee shall cease to be eligible in accordance with the provisions of Section 7.09 and shall fail to resign after written request therefor by the Company or by any such Securityholder; or

(c) The holders of a majority in aggregate principal amount of the Securities of any series at the time Outstanding may at any time remove the Trustee with respect to such

series by so notifying the Trustee and the Company and may appoint a successor Trustee for such series with the consent of the Company.

Section 7.11 Acceptance of Appointment By Successor .

without any further act, deed or conveyance, shall become vested with all the rights, powers, trusts and duties of the retiring Trustee with respect to the Securities of that or those series to which the appointment of such successor trustee relates; but, on request of the Company or any successor trustee, such retiring Trustee shall duly assign, transfer and deliver to such successor trustee, to the extent contemplated by such supplemental indenture, the property and money held by such retiring Trustee hereunder with respect to the Securities of that or those series to which the appointment of such successor trustee relates.

(d) No successor trustee shall accept its appointment unless at the time of such acceptance such successor trustee shall be qualified and eligible under this Article.

Section 7.12 Merger, Conversion, Consolidation or Succession to Business .

Section 7.13 Preferential Collection of Claims Against the Company .

Section 7.14 Notice of Default .

If any Event of Default occurs and is continuing and if such Event of Default is actually known to a Responsible Officer of the Trustee, the Trustee shall send to each Securityholder in the manner and to the extent provided in Section 313(c) of the Trust Indenture Act notice of the Event of Default within the later of 90 days after it occurs and 30 days after it is actually known to a Responsible Officer of the Trustee or written notice of it is received by the Trustee, unless such Event of Default has been cured; provided , however , that, except in the case of a default in the payment of the principal of (or premium, if any) or interest on any Security, the Trustee shall be protected in withholding such notice if and so long as it in good faith determines that the withholding of such notice is in the interest of the Securityholders.

ARTICLE 8
CONCERNING THE SECURITYHOLDERS

Section 8.01 Evidence of Action by Securityholders .

Section 8.02 Proof of Execution by Securityholders .

(a) The fact and date of the execution by any such Person of any instrument may be proved in any reasonable manner acceptable to the Trustee.

Section 8.03 Who May be Deemed Owners .

Section 8.04 Certain Securities Owned by Company Disregarded .

Section 8.05 Actions Binding on Future Securityholders .

holders and owners of such Security, and of any Security issued in exchange therefor, on registration of transfer thereof or in place thereof, irrespective of whether or not any notation in regard thereto is made upon such Security. Any action taken by the holders of the majority or percentage in aggregate principal amount of the Securities of a particular series specified in this Indenture in connection with such action shall be conclusively binding upon the Company, the Trustee and the holders of all the Securities of that series.

ARTICLE 9
SUPPLEMENTAL INDENTURES

Section 9.01 Supplemental Indentures Without the Consent of Securityholders .

(a) to cure any ambiguity, defect, or inconsistency herein or in the Securities of any series;

(b) to comply with Article 10 ;

(f) to make any change that does not adversely affect the rights of any Securityholder in any material respect;

(h) to evidence and provide for the acceptance of appointment hereunder by a successor trustee or to appoint a separate trustee with respect to any series; or

(i) to comply with any requirements of the Commission or any successor in connection with the qualification of this Indenture under the Trust Indenture Act.

The Trustee is hereby authorized to join with the Company in the execution of any such supplemental indenture, and to make any further appropriate agreements and stipulations that may be therein contained, but the Trustee shall not be obligated to enter into any such supplemental indenture that affects the Trustee’s own rights, duties or immunities under this Indenture or otherwise.

Section 9.02 Supplemental Indentures With Consent of Securityholders .

Section 9.03 Effect of Supplemental Indentures .

Section 9.04 Securities Affected by Supplemental Indentures .

Securities of any series affected by a supplemental indenture, authenticated and delivered after the execution of such supplemental indenture pursuant to the provisions of this Article or of Section 10.01 , may bear a notation in form approved by the Company, provided such form meets the requirements of any securities exchange upon which such series may be listed, as to any matter provided for in such supplemental indenture. If the Company shall so determine, new Securities of that series so modified as to conform, in the opinion of the Board of Directors, to any modification of this Indenture contained in any such supplemental indenture may be prepared by the Company, authenticated by the Trustee and delivered in exchange for the Securities of that series then Outstanding.

Section 9.05 Execution of Supplemental Indentures .

ARTICLE 10
SUCCESSOR ENTITY

Section 10.01 Company May Consolidate, Etc .

successors) authorized to acquire and operate the same; provided , however , (a) the Company hereby covenants and agrees that, upon any such consolidation or merger (in each case, if the Company is not the survivor of such transaction), sale, conveyance, transfer or other disposition, the due and punctual payment of the principal of (premium, if any) and interest on all of the Securities of all series in accordance with the terms of each series, according to their tenor, and the due and punctual performance and observance of all the covenants and conditions of this Indenture with respect to each series or established with respect to such series pursuant to Section 2.01 to be kept or performed by the Company shall be expressly assumed, by supplemental indenture (which shall conform to the provisions of the Trust Indenture Act, as then in effect) executed and delivered to the Trustee by the entity formed by such consolidation, or into which the Company shall have been merged, or by the entity which shall have acquired such property and (b) in the event that the Securities of any series then Outstanding are convertible into or exchangeable for shares of common stock or other securities of the Company, such entity shall, by such supplemental indenture, make provision so that the Securityholders of Securities of that series shall thereafter be entitled to receive upon conversion or exchange of such Securities the number of securities or property to which a holder of the number of shares of common stock or other securities of the Company deliverable upon conversion or exchange of those Securities would have been entitled had such conversion or exchange occurred immediately prior to such consolidation, merger, sale, conveyance, transfer or other disposition. If the Company is not the surviving entity of any such transaction, the Company or the continuing entity agrees to deliver to the Trustee an Officer’s Certificate and Opinion of Counsel stating that the transaction and the supplemental indenture complies with this Section 10.01 and that all conditions precedent herein relating to the transaction have been satisfied.

Section 10.02 Successor Entity Substituted .

ARTICLE 11
SATISFACTION AND DISCHARGE

Section 11.01 Satisfaction and Discharge of Indenture .

If at any time: (a) the Company shall have delivered to the Trustee for cancellation all Securities of a series theretofore authenticated and not delivered to the Trustee for cancellation (other than any Securities that shall have been destroyed, lost or stolen and that shall have been replaced or paid as provided in Section 2.07 and Securities for whose payment money or Governmental Obligations have theretofore been deposited in trust or segregated and held in trust by the Company and thereupon repaid to the Company or discharged from such trust, as provided in Section 11.05 ); or (b) all such Securities of a particular series not theretofore delivered to the Trustee for cancellation shall have become due and payable, or are by their terms to become due and payable within one year or are to be called for redemption within one year under arrangements satisfactory to the Trustee for the giving of notice of redemption, and the Company shall deposit or cause to be deposited with the Trustee as trust funds the entire amount in moneys or Governmental Obligations or a combination thereof, sufficient in the opinion of a nationally recognized firm of independent public accountants expressed in a written certification thereof delivered to the Trustee, to pay at maturity or upon redemption all Securities of that series not theretofore delivered to the Trustee for cancellation, including principal (and premium, if any) and interest due or to become due to such date of maturity or date fixed for redemption, as the case may be, and if the Company shall also pay or cause to be paid all other sums payable hereunder with respect to such series by the Company then this Indenture shall thereupon cease to be of further effect with respect to such series except for the provisions of Sections 2.03 , 2.05 , 2.07 , 4.01 , 4.02 , 4.03 and 7.10 , that shall survive until the date of maturity or redemption date, as the case may be, and Sections 7.06 and 11.05 , that shall survive to such date and thereafter, and the Trustee, on demand of the Company and at the cost and expense of the Company shall execute such instruments reasonably requested by the Company acknowledging satisfaction of and discharging this Indenture with respect to such series.

Section 11.02 Discharge of Obligations .

Thereafter, Sections 7.06 and 11.05 shall survive.

Section 11.03 Deposited Moneys to be Held in Trust .

All moneys or Governmental Obligations deposited with the Trustee pursuant to Sections 11.01 or 11.02 shall be held in trust and shall be available for payment as due, either

directly or through any paying agent (including the Company acting as its own paying agent), to the holders of the particular series of Securities for the payment or redemption of which such moneys or Governmental Obligations have been deposited with the Trustee.

Section 11.04 Payment of Moneys Held by Paying Agents .

Section 11.05 Repayment to Company .

ARTICLE 12
IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS AND DIRECTORS

Section 12.01 No Recourse .

stockholder, officer or director as such, because of the creation of the indebtedness hereby authorized, or under or by reason of the obligations, covenants or agreements contained in this Indenture or in any of the Securities or implied therefrom, are hereby expressly waived and released as a condition of, and as a consideration for, the execution of this Indenture and the issuance of such Securities.

ARTICLE 13
MISCELLANEOUS PROVISIONS

Section 13.01 Effect on Successors and Assigns .

All the covenants, stipulations, promises and agreements in this Indenture made by or on behalf of the Company shall bind its successors and assigns, whether so expressed or not.

Section 13.02 Actions by Successor .

Section 13.03 Surrender of Company Powers .

Section 13.04 Notices .

Section 13.05 Governing Law; Jury Trial Waiver .

THIS INDENTURE AND EACH SECURITY, AND ANY CLAIM, CONTROVERSY OR DISPUTE ARISING UNDER OR RELATED TO THIS INDENTURE AND EACH

SECURITY, SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK (WITHOUT REGARD TO THE CONFLICTS OF LAWS PROVISIONS THEREOF). EACH OF THE COMPANY AND THE TRUSTEE HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATING TO THIS INDENTURE, THE SECURITIES OR THE TRANSACTION CONTEMPLATED HEREBY.

Section 13.06 Treatment of Securities as Debt .

It is intended that the Securities will be treated as indebtedness and not as equity for federal income tax purposes. The provisions of this Indenture shall be interpreted to further this intention.

Section 13.07 Certificates and Opinions as to Conditions Precedent .

Section 13.08 Payments on Business Days .

Section 13.09 Conflict with Trust Indenture Act .

Section 13.10 Counterparts .

Section 13.11 Separability .

Section 13.12 Compliance Certificates .

Section 13.13 USA PATRIOT ACT .

Section 13.14 Calculations .

ARTICLE 14
SUBORDINATION OF SECURITIES

Section 14.01 Subordination Terms .

The payment by the Company of the principal of, premium, if any, and interest on any series of Securities issued hereunder shall be subordinated to the extent set forth in an indenture supplemental hereto relating to such series.

IN WITNESS WHEREOF , the parties hereto have caused this Indenture to be duly executed all as of the day and year first above written.

	RUBIUS THERAPEUTICS, INC. , as Issuer


	By:

	Name:

	Title:


	[TRUSTEE] , as Trustee


	By:

	Name:

	Title:

Signature Page to Form of Indenture

TRUST INDENTURE ACT CROSS-REFERENCE TABLE(2)

Section of Trust Indenture Act of 1939, as amended		Section of Indenture
310(a)		7.09
310(b)		7.08 7.10
310(c)		Inapplicable
311(a)		7.13
311(b)		7.13
311(c)		Inapplicable
312(a)		5.01 5.02(a)
312(b)		5.02(c)
312(c)		5.02(c)
313(a)		5.04(a)
313(b)		5.04(b)
313(c)		5.04(a) 5.04(b)
313(d)		5.04(c)
314(a)		5.03 13.12
314(b)		Inapplicable
314(c)		13.07(a)
314(d)		Inapplicable
314(e)		13.07(b)
314(f)		Inapplicable
315(a)		7.01(a) 7.01(b)
315(b)		7.14
315(c)		7.01(a)
315(d)		7.01(b)
315(e)		6.07
316(a)		6.06 8.04
316(b)		6.04
316(c)		8.01
317(a)		6.02
317(b)		4.03
318(a)		13.09

(2) This Cross-Reference Table does not constitute part of the Indenture and shall not have any bearing on the interpretation of any of its terms or provisions.

Exhibit 5.1

Goodwin Procter LLP
100 Northern Avenue
Boston, MA 02210

goodwinlaw.com

+1 617 570 1000

August 1, 2019

Rubius Therapeutics, Inc.

399 Binney Street, Suite 300

Cambridge, Massachusetts

Re: Securities Being Registered under Registration Statement on Form S-3

Ladies and Gentlemen:

We have acted as counsel to you in connection with your filing of a Registration Statement on Form S-3 (as amended or supplemented, the “Registration Statement”) pursuant to the Securities Act of 1933, as amended (the “Securities Act”), relating to the registration by Rubius Therapeutics, Inc., a Delaware corporation (the “Company”), of up to $450,000,000 of any combination of (i) common stock, par value $0.001 per share (the “Common Stock”), of the Company, (ii) preferred stock, par value $0.001 per share, of the Company (the “Preferred Stock”), (iii) debt securities of the Company (“Debt Securities”), (iv) warrants to purchase Common Stock, Preferred Stock, Debt Securities or Units (as defined below ) (“Warrants”) and (v) units comprised of Common Stock, Preferred Stock, Debt Securities, Warrants and other securities in any combination (“Units”). The Common Stock, Preferred Stock, Debt Securities, Warrants and Units are sometimes referred to collectively herein as the “Securities.” Securities may be issued in an unspecified number (with respect to Common Stock, Preferred Stock, Warrants and Units) or in an unspecified principal amount (with respect to Debt Securities). The Registration Statement provides that the Securities may be offered separately or together, in separate series, in amounts, at prices and on terms to be set forth in one or more prospectus supplements (each a “Prospectus Supplement”) to the prospectus contained in the Registration Statement.

We have reviewed such documents and made such examination of law as we have deemed appropriate to give the opinions set forth below. We have relied, without independent verification, on certificates of public officials and, as to matters of fact material to the opinions set forth below, on certificates of officers of the Company.

The opinions set forth below are limited to the Delaware General Corporation Law and the law of New York.

For purposes of the opinions set forth below, without limiting any other exceptions or qualifications set forth herein, we have assumed that (i) each of the Debt Securities, Warrants and Units, and the indentures, warrant agreements, unit agreements and other agreements

governing Securities offered pursuant to the Registration Statement will be governed by the internal law of New York and (ii) after the issuance of any Securities offered pursuant to the Registration Statement, the total number of issued shares of Common Stock or Preferred Stock, as applicable, together with the total number of shares of such stock issuable upon the exercise, exchange, conversion or settlement, as the case may be, of any exercisable, exchangeable or convertible security (including without limitation any Unit), as the case may be, then outstanding, will not exceed the total number of authorized shares of Common Stock or Preferred Stock, as applicable, available for issuance under the Company’s certificate of incorporation as then in effect (the “Charter”).

For purposes of the opinions set forth below, we refer to the following as the “Future Authorization and Issuance” of Securities:

· with respect to any of the Securities, (a) the authorization by the Company of the amount, terms and issuance of such Securities (the “Authorization”) and (b) the issuance of such Securities in accordance with the Authorization therefor upon the receipt by the Company of the consideration (which, in the case of shares of Common Stock or Preferred Stock, is not less than the par value of such shares) to be paid therefor in accordance with the Authorization;

· with respect to Preferred Stock, (a) the establishment of the terms of such Preferred Stock by the Company in conformity with the Charter and applicable law and (b) the execution, acknowledgement and filing with the Delaware Secretary of State, and the effectiveness of, a certificate of designations to the Charter setting forth the terms of such Preferred Stock in accordance with the Charter and applicable law;

· with respect to Debt Securities, (a) the authorization, execution and delivery of the indenture or a supplemental indenture relating to such Securities by the Company and the trustee thereunder and/or (b) the establishment of the terms of such Securities by the Company in conformity with the applicable indenture or supplemental indenture and applicable law, and (c) the execution, authentication and issuance of such Securities in accordance with the applicable indenture or supplemental indenture and applicable law; and

· with respect to Warrants or Units, (a) the authorization, execution and delivery by the Company and the other parties thereto of any agreement under which such Securities are to be issued, and (b) the establishment of the terms of such Securities and the issuance of such Securities in conformity with those terms, the terms of any applicable agreement and applicable law.

Based upon the foregoing, and subject to the additional qualifications set forth below, we are of the opinion that:

1. Upon the Future Authorization and Issuance of shares of Common Stock, such shares of Common Stock will be validly issued, fully paid and nonassessable.

2. Upon the Future Authorization and Issuance of shares of Preferred Stock, such shares of Preferred Stock will be validly issued, fully paid and nonassessable.

3. Upon the Future Authorization and Issuance of Debt Securities, such Debt Securities will be valid and binding obligations of the Company.

4. Upon the Future Authorization and Issuance of Warrants, such Warrants will be valid and binding obligations of the Company.

5. Upon the Future Authorization and Issuance of Units, such Units will be valid and binding obligations of the Company.

The opinions expressed above are subject to bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and other similar laws of general application affecting the rights and remedies of creditors and to general principles of equity.

This opinion letter and the opinions it contains shall be interpreted in accordance with the Legal Opinion Principles issued by the Committee on Legal Opinions of the American Bar Association’s Business Law Section as published in 53 Business Lawyer 831 (May 1998).

We hereby consent to the inclusion of this opinion as Exhibit 5.1 to the Registration Statement and to the references to our firm under the caption “Legal Matters” in the Registration Statement. In giving our consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations thereunder.

	Very truly yours,

	/s/ GOODWIN PROCTER LLP

	GOODWIN PROCTER LLP

Exhibit 5.2

Goodwin Procter LLP

100 Northern Avenue
Boston, MA 02210

goodwinlaw.com

+1 617 570 1000

August 1, 2019

Rubius Therapeutics, Inc.

399 Binney Street, Suite 300

Cambridge, Massachusetts

Re: Securities Registered under Registration Statement on Form S-3

Ladies and Gentlemen:

We have acted as counsel to you in connection with your filing of a Registration Statement on Form S-3 (as amended or supplemented, the “Registration Statement”) filed on August 1, 2019 with the Securities and Exchange Commission (the “Commission”) pursuant to the Securities Act of 1933, as amended (the “Securities Act”), relating to the registration by Rubius Therapeutics, Inc., a Delaware corporation (the “Company”) of up to $450,000,000 of any combination of securities of the types specified therein. Reference is made to our opinion letter dated August 1, 2019 and included as Exhibit 5.1 to the Registration Statement. We are delivering this supplemental opinion letter in connection with the distribution agreement prospectus supplement (the “Prospectus Supplement”) contained in the Registration Statement. The Prospectus Supplement relates to the offering by the Company of up to $100,000,000 in shares (the “Shares”) of the Company’s common stock, par value $0.001 per share (“Common Stock”) covered by the Registration Statement. The Shares are being offered and sold by the sales agents named in, and pursuant to, the distribution agreement among the Company and such sales agents.

We have reviewed such documents and made such examination of law as we have deemed appropriate to give the opinion set forth below. We have relied, without independent verification, on certificates of public officials and, as to matters of fact material to the opinion set forth below, on certificates of officers of the Company.

For purposes of the opinion set forth below, we have assumed that the Shares are issued for a price per share equal to or greater than the minimum price authorized by the Company’s board of directors (or a duly authorized committee of the board of directors) prior to the date hereof (the “Minimum Price”) and that no event occurs that causes the number of authorized shares of Common Stock available for issuance by the Company to be less than the number of then unissued Shares that may be issued for the Minimum Price.

For purposes of the opinion set forth below, we refer to the following as “Future Approval and Issuance”: (a) the approval by the Company’s board of directors (or a duly authorized committee of the board of directors) of the issuance of the Shares (the “Approval”)

and (b) the issuance of the Shares in accordance with the Approval and the receipt by the Company of the consideration (which shall not be less than the par value of such Shares) to be paid in accordance with the Approval.

The opinion set forth below is limited to the Delaware General Corporation Law.

Based on the foregoing, we are of the opinion that the Shares have been duly authorized and, upon Future Approval and Issuance, will be validly issued, fully paid and nonassessable.

This opinion is being furnished to you for submission to the Commission as an exhibit to the Registration Statement. We hereby consent to the filing of this opinion letter as Exhibit 5.2 to the Registration Statement and the reference to our firm under the caption “Legal Matters” in the Registration Statement. In giving our consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations thereunder.

	Very truly yours,

	/s/ GOODWIN PROCTER LLP

	GOODWIN PROCTER LLP

Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of Rubius Therapeutics, Inc. of our report dated March 28, 2019 relating to the financial statements, which appears in Rubius Therapeutics, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2018. We also consent to the reference to us under the heading “Experts” in such Registration Statement.

/s/ PricewaterhouseCoopers LLP

Boston, Massachusetts

August 1, 2019