Exhibit 1.1

Execution Version

CLOVIS ONCOLOGY, INC.

1,837,898 Shares of Common Stock

(par value $0.001 per share)

Underwriting Agreement

April 16, 2018

J.P. MORGAN SECURITIES LLC

MERRILL LYNCH, PIERCE, FENNER & SMITH

                    INCORPORATED

c/o

J. P. Morgan Securities LLC

383 Madison Avenue

New York, New York 10179

Merrill Lynch, Pierce, Fenner & Smith

                    Incorporated

One Bryant Park

New York, New York 10036

Ladies and Gentlemen:

Clovis Oncology, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to you, the several underwriters listed in Schedule 1 hereto (the “Underwriters”), an aggregate of 1,837,898 shares (the “Underwritten Shares”) of common stock, par value $0.001 per share, of the Company (the “Common Stock”) and, at the option of the Underwriters, up to an additional 275,684 shares of common stock of the Company (the “Option Shares”). The Underwritten Shares and the Option Shares are herein referred to as the “Shares.” The shares of Common Stock of the Company to be issued and outstanding after giving effect to the sale of the Shares are referred to herein as the “Stock.”

The Company hereby confirms its agreement with the several Underwriters concerning the purchase and sale of the Shares, as follows:

1. Registration Statement . The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Securities Act”), a registration statement on Form S-3 (File No. 333-215400), as amended by Post-Effective Amendment No. 1 thereto, including a prospectus, relating to the Shares. Such registration statement, as amended at the time it became effective, including the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Securities Act to be part of the registration statement at the time of its effectiveness (“Rule 430 Information”), is referred to herein as the “Registration Statement;” and as used herein, the term “Preliminary Prospectus” means any prospectus filed with the Commission pursuant to Rule 424(b) under the Securities Act and the prospectus included in the Registration Statement at the time of its effectiveness that omits Rule 430 Information, and the term “Prospectus” means the prospectus in the form first used (or made available upon request of purchasers pursuant to Rule 173 under the Securities Act) in connection with confirmation of sales of the Shares. If the Company has filed an abbreviated registration statement pursuant to Rule 462(b) under the Securities Act (the “Rule 462 Registration

Statement”), then any reference herein to the term “Registration Statement” shall be deemed to include such Rule 462 Registration Statement. Any reference in this underwriting agreement (this “Agreement”) to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, as of the effective date of the Registration Statement or the date of the Preliminary Prospectus or the Prospectus, as the case may be, and any reference to “amend,” “amendment” or “supplement” with respect to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed after such date under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Exchange Act”) that are deemed to be incorporated by reference therein. Capitalized terms used but not defined herein shall have the meanings given to such terms in the Registration Statement and the Prospectus.

At or prior to the Applicable Time (as defined below), the Company had prepared the following information (collectively with the pricing information set forth on Annex B, the “Pricing Disclosure Package”): a Preliminary Prospectus dated April 16, 2018 and each “free-writing prospectus” (as defined pursuant to Rule 405 under the Securities Act) listed on Annex B hereto.

“Applicable Time” means 5:30 p.m., New York City time, on April 16, 2018.

2. Purchase of the Shares by the Underwriters .

(a) The Company agrees to issue and sell the Underwritten Shares to the several Underwriters as provided in this Agreement, and each Underwriter, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, agrees, severally and not jointly, to purchase from the Company the respective number of Underwritten Shares set forth opposite such Underwriter’s name in Schedule 1 hereto at a price per share of $51.281425 (the “Purchase Price”).

In addition, the Company agrees to issue and sell the Option Shares to the several Underwriters as provided in this Agreement, and the Underwriters, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, shall have the option to purchase, severally and not jointly, from the Company the Option Shares at the Purchase Price less an amount per share equal to any dividends or distributions declared by the Company and payable on the Underwritten Shares but not payable on the Option Shares.

If any Option Shares are to be purchased, the number of Option Shares to be purchased by each Underwriter shall be the number of Option Shares which bears the same ratio to the aggregate number of Option Shares being purchased as the number of Underwritten Shares set forth opposite the name of such Underwriter in Schedule 1 hereto (or such number increased as set forth in Section 10 hereof) bears to the aggregate number of Underwritten Shares being purchased from the Company by the several Underwriters, subject, however, to such adjustments to eliminate any fractional Shares as the Underwriters in their sole discretion shall make.

The Underwriters may exercise the option to purchase the Option Shares at any time in whole, or from time to time in part, on or before the thirtieth day following the date of the Prospectus, by written notice from the Underwriters to the Company. Such notice shall set forth the aggregate number of Option Shares as to which the option is being exercised and the date and time when the Option Shares are to be delivered and paid for, which may be the same date and time as the Closing Date (as hereinafter defined) but shall not be earlier than the Closing Date nor later than the tenth full business day after the date of such notice (unless such time and date are postponed in accordance with the provisions of Section 10 hereof). Except with respect to Option Shares to be purchased on the Closing Date, if any, any such notice shall be given at least two business days prior to the date and time of delivery specified therein.

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(b) The Company understands that the Underwriters intend to make a public offering of the Shares as soon after the effectiveness of this Agreement as in the judgment of the Underwriters is advisable, and initially to offer the Shares on the terms set forth in the Pricing Disclosure Package. The Company acknowledges and agrees that the Underwriters may offer and sell Shares to or through any affiliate of an Underwriter and that any such affiliate may offer and sell Shares purchased by it to or through any Underwriter.

(c) Payment for the Shares shall be made by wire transfer in immediately available funds to the account specified by the Company to the Underwriters in the case of the Underwritten Shares, at the offices of Latham & Watkins LLP, counsel for the Underwriters, at 12670 High Bluff Drive, San Diego, CA 92130 at 10:00 A.M., New York City time, on April 19, 2018, or at such other time or place on the same or such other date, not later than the fifth business day thereafter, as the Underwriters and the Company may agree upon in writing or, in the case of the Option Shares, on the date and at the time and place specified by the Underwriters in the written notice of the Underwriters’ election to purchase such Option Shares. The time and date of such payment for the Underwritten Shares is referred to herein as the “Closing Date,” and the time and date for such payment for the Option Shares, if other than the Closing Date, is herein referred to as the “Additional Closing Date.”

Payment for the Shares to be purchased on the Closing Date or the Additional Closing Date, as the case may be, shall be made against delivery to the Underwriters for the respective accounts of the several Underwriters of the Shares to be purchased on the Closing Date or the Additional Closing Date, as the case may be, with any transfer taxes payable in connection with the sale of such Shares duly paid by the Company. Delivery of the Shares shall be made through the facilities of The Depository Trust Company (“DTC”) unless the Underwriters shall otherwise instruct.

(d) The Company acknowledges and agrees that the Underwriters are acting solely in the capacity of an arm’s length contractual counterparty to the Company with respect to the offering of Shares contemplated hereby (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, the Underwriters are not 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 the Underwriters shall have no responsibility or liability to the Company with respect thereto. Any review by the Underwriters of the Company, the transactions contemplated hereby or other matters relating to such transactions will be performed solely for the benefit of the Underwriters and shall not be on behalf of the Company.

3. Representations and Warranties of the Company . The Company represents and warrants to each Underwriter that:

(a) Preliminary Prospectus. No order preventing or suspending the use of any Preliminary Prospectus included in the Pricing Disclosure Package has been issued by the Commission, and the Preliminary Prospectus included in the Pricing Disclosure Package, at the time of filing thereof, complied in all material respects with the Securities Act, and such Preliminary Prospectus, at the time of filing thereof, did not contain any 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 that the Company makes no representation or warranty with respect to any statements or omissions made

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in reliance upon and in conformity with information furnished to the Company in writing by such Underwriter expressly for use in such Preliminary Prospectus, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof.

(b)     Pricing Disclosure Package . The Pricing Disclosure Package as of the Applicable Time did not, and as of the Closing Date will not, contain any 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 that the Company makes no representation or warranty with respect to any statements or omissions made in reliance upon and in conformity with information furnished to the Company in writing by such Underwriter expressly for use in such Pricing Disclosure Package, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof. No statement of material fact included in the Prospectus has been omitted from the Pricing Disclosure Package and no statement of material fact included in the Pricing Disclosure Package that is required to be included in the Prospectus has been omitted therefrom.

(c)     Issuer Free Writing Prospectus. Other than the Registration Statement, the Preliminary Prospectus included in the Pricing Disclosure Package and the Prospectus, the Company (including its agents and representatives, other than the Underwriters in their capacity as such) has not made, used, prepared, authorized, approved or referred to and will not make, prepare, use, authorize, approve or refer to any “written communication” (as defined in Rule 405 under the Securities Act) that constitutes an offer to sell or solicitation of an offer to buy the Shares (each such communication by the Company or its agents and representatives (other than a communication referred to in clause (i) below) an “Issuer Free Writing Prospectus”) other than (i) any document not constituting a prospectus pursuant to Section 2(a)(10)(a) of the Securities Act or Rule 134 under the Securities Act or (ii) the documents listed on Annex B hereto, each electronic road show and any other written communications approved in writing in advance by the Underwriters. Each such Issuer Free Writing Prospectus complied in all material respects with the Securities Act, has been or will be (within the time period specified in Rule 433) filed in accordance with the Securities Act (to the extent required thereby) and, when taken together with any other Issuer Free Writing Prospectus and the Preliminary Prospectus accompanying, or delivered prior to delivery of, such Issuer Free Writing Prospectus, did not, and as of the Closing Date and as of the Additional Closing Date, as the case may be, will not, contain any 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 that the Company makes no representation or warranty with respect to any statements or omissions made in each such Issuer Free Writing Prospectus or Preliminary Prospectus in reliance upon and in conformity with information furnished to the Company in writing by such Underwriter expressly for use in such Issuer Free Writing Prospectus or Preliminary Prospectus, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof. Each such Issuer Free Writing Prospectus, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Shares or until any earlier date that the Company notified or notifies the Underwriters as described in Section 4(d), did not, does not and will not include any information that conflicted, conflicts or will conflict with the information contained in the Registration Statement or the Prospectus.

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(d)     Registration Statement and Prospectus. The Registration Statement is an “automatic shelf registration statement” as defined under Rule 405 of the Securities Act that has been filed with the Commission not earlier than three years prior to the date hereof; and no notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act has been received by the Company. No order suspending the effectiveness of the Registration Statement has been issued by the Commission, and no proceeding for that purpose or pursuant to Section 8A of the Securities Act against the Company or related to the offering of the Shares has been initiated or to the knowledge of the Company threatened by the Commission; as of the applicable effective date of the Registration Statement and any post-effective amendment thereto, the Registration Statement and any such post-effective amendment complied and will comply in all material respects with the Securities Act, and did not 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 in order to make the statements therein not misleading; and as of the date of the Prospectus and any amendment or supplement thereto and as of the Closing Date and as of the Additional Closing Date, as the case may be, the Prospectus complied and will comply in all material respects with the Securities Act and will not contain any 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 that the Company makes no representation or warranty with respect to (i) that part of the Registration Statement that constitutes the Statement of Eligibility and Qualification (Form T-1) of the Trustee under the Trust Indenture Act or (ii) any statements or omissions made in reliance upon and in conformity with information furnished to the Company in writing by such Underwriter expressly for use in the Registration Statement and the Prospectus and any amendment or supplement thereto, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof.

(e)     Incorporated Documents. The documents incorporated by reference in the Registration Statement, the Prospectus and the Pricing Disclosure Package, when they were filed with the Commission (after giving effect to any amendment or supplement filed with the Commission prior to the Applicable Time), conformed in all material respects to the requirements of the Exchange Act, and none of such documents contained any untrue statement of a material fact or omitted to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; and any further documents so filed and incorporated by reference in the Registration Statement, the Prospectus or the Pricing Disclosure Package during the Prospectus Delivery Period (as defined below), when such documents are filed with the Commission, will conform in all material respects to the requirements of the Exchange Act and will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(f)     Financial Statements. The financial statements (including the related notes thereto) of the Company and its consolidated subsidiaries included or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus comply in all material respects with the applicable requirements of the Securities Act and the Exchange Act, as applicable, and present fairly, in all material respects, the financial position of the Company and its consolidated subsidiaries as of the dates indicated and the results of their operations and the changes in their cash flows for the periods specified; such financial statements have been prepared in conformity with generally accepted accounting principles in the United States applied on a consistent basis throughout the periods covered thereby, except in the case of unaudited financial statements, which do not contain certain footnotes as permitted by the rules of the Commission, and any supporting schedules included or incorporated by reference in the Registration Statement present fairly, in all material respects, the information required to be

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stated therein; and the other financial information included or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus has been derived from the accounting records of the Company and its consolidated subsidiaries and presents fairly, in all material respects, the information shown thereby.

(g)     No Material Adverse Change. Since the date of the most recent financial statements of the Company included or incorporated by reference in the Pricing Disclosure Package and the Prospectus, (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 and warrants described as outstanding in, and the grant of options and awards under existing equity incentive plans described in, the Registration Statement, the Pricing Disclosure Package and the Prospectus), or long-term debt or any material change in short-term debt 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 involving 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 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, except in each case as otherwise disclosed in the Pricing Disclosure Package and the Prospectus.

(h)     Organization and Good Standing. The Company and each of its subsidiaries have been duly organized and are validly existing and in good standing (where such concept is recognized) 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, or would reasonably be expected to 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 (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 21.1 to the Company’s Form 10-K for the year ended December 31, 2017. None of the subsidiaries of the Company have any assets, liabilities or operations that are material to the business and operations of the Company and its subsidiaries taken as a whole.

(i)     Capitalization. The Company has an authorized capitalization as set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus under the headings “Capitalization,” “Description of Common Stock,” “Description of Other Capital Stock and Governing Documents” and “Description of Debt Securities;” 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 are not subject to any pre-emptive or similar rights; except as described in or expressly contemplated by the Pricing Disclosure Package and the Prospectus, there are no

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outstanding rights (including, without limitation, pre-emptive rights), warrants or options to acquire, or instruments convertible into or exchangeable for, any shares of capital stock or other equity interest in the Company or any of its subsidiaries, or any contract, commitment, agreement, understanding or arrangement of any kind relating to the issuance of any capital stock of the Company or any such subsidiary, any such convertible or exchangeable securities or any such rights, warrants or options; the capital stock of the Company conforms in all material respects to the description thereof contained in the Registration Statement, the Pricing Disclosure Package and the 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.

(j)     Stock Options. 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 Plans”), (i) each Stock Option intended to qualify as an “incentive stock option” under Section 422 of the Code so qualified as of the applicable Grant Date (as defined below), (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, and (iv) each such grant was properly accounted for in accordance with accounting principles generally accepted in the United States in the financial statements (including the related notes) of the Company. Each Company Stock Plan is accurately described in all material respects in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(k)     Due Authorization. The Company has full right, power and authority to execute and deliver this Agreement and to perform its obligations hereunder; and all action required to be taken for the due and proper authorization, execution and delivery by it of this Agreement and the consummation by it of the transactions contemplated hereby has been duly and validly taken.

(l)     Underwriting Agreement. This Agreement has been duly authorized, executed and delivered by the Company.

(m)     The Shares. The Shares to be issued and sold hereunder have been duly authorized by the Company and, when issued and delivered and paid for as provided herein, 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 Pricing Disclosure Package and the Prospectus; and the issuance of the Shares is not subject to any preemptive or similar rights.

(n)     Listing . The Shares have been approved for listing on the Nasdaq Global Select Market (“Nasdaq Market”), subject to notice of issuance.

(o)     Descriptions of the Underwriting Agreement. This Agreement conforms in all material respects to the description thereof contained in the Pricing Disclosure Package and the Prospectus.

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(p)     No Violation or Default. Neither the Company nor any of its subsidiaries is (i) in violation of its charter or by-laws or similar organizational documents; (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.

(q)     No Conflicts. The execution, delivery and performance by the Company of this Agreement, the issuance and sale of the Shares and the consummation by the Company of the transactions contemplated by this 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, right or asset 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, right 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 similar 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 applicable to the Company, except, in the case of clauses (i) and (iii) above, for any such conflict, breach, violation, default, termination, modification, acceleration, lien, charge or encumbrance that would not, individually or in the aggregate, have a Material Adverse Effect.

(r)     No Consents Required. No consent, filing, approval, authorization, order, 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, the issuance and sale of the Shares and the consummation by the Company of the transactions contemplated by this Agreement, except for the registration of the Shares under the Securities Act and such filings, consents, approvals, authorizations, orders and registrations or qualifications (i) which have been obtained or made or (ii) as may be required by the Financial Industry Regulatory Authority, Inc. (“FINRA”), the Nasdaq Market and under applicable state securities laws in connection with the purchase and distribution of the Shares by the Underwriters.

(s)     No Integration . Neither the Company nor any of its affiliates has, prior to the date hereof, made any offer or sale of any securities that would be integrated with the offer and sale of the Shares contemplated by this Agreement pursuant to the Securities Act or the interpretations thereof by the Commission.

(t)     Legal Proceedings. Except as described in the Registration Statement, the Pricing Disclosure Package 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 a party or to which any property of the Company or any of its subsidiaries is subject that, individually or in the aggregate, if determined adversely to the Company or any of its subsidiaries, would reasonably be expected to have a Material Adverse Effect; to the knowledge of the Company, no such Actions are threatened or

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contemplated by any governmental or regulatory authority or threatened by others that do not arise out of the same underlying facts and allegations contained in the Actions disclosed in the Pricing Disclosure Package and the Prospectus; and (i) there are no current or pending Actions that are required under the Securities Act to be described in the Registration Statement, the Pricing Disclosure Package or the Prospectus that are not so described in the Registration Statement, the Pricing Disclosure Package and the Prospectus and (ii) there are no statutes, regulations or contracts or other documents that are required under the Securities Act to be filed as exhibits to the Registration Statement (in the case of contracts or other documents) or described in the Registration Statement, the Pricing Disclosure Package or the Prospectus that are not so filed as exhibits to the Registration Statement (in the case of contracts or other documents) or described in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(u)     Independent Accountants . Ernst & Young LLP, who have audited certain consolidated financial statements of the Company and its subsidiaries, 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 (United States) and as required by the Securities Act.

(v)     Title to Real and Personal Property . The Company and its subsidiaries have good and marketable title in fee simple (in the case of real property, if any) to, or have valid rights to lease or otherwise use, all items of real and tangible personal property and assets 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.

(w)     Title to Intellectual Property. The Company and its subsidiaries own, or have obtained valid and enforceable licenses for, or other rights to use, the inventions, patent applications, patents, trademarks (both registered and unregistered), trade names, copyrights, trade secrets and other proprietary information (collectively, the “Intellectual Property”) described in the Registration Statement, the Pricing Disclosure Package and the Prospectus as being owned or licensed by them, used in, or necessary for the conduct of, their respective businesses as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, except as would not reasonably be expected to have a Material Adverse Effect; and (i) to the Company’s knowledge, there is no infringement, misappropriation or violation by third parties of any such Intellectual Property that would have a Material Adverse Effect; (ii) to the Company’s knowledge, there is no pending or threatened action, suit, proceeding or claim by others that the Company or its subsidiaries infringe, misappropriate or otherwise violate any Intellectual Property rights of others, the Company has not received any written notice of such claim, and the Company is unaware of any facts which would form a reasonable basis for a successful claim of such infringement, misappropriation or violation, in each case that would have a Material Adverse Effect; (iii) there is no pending or, to the Company’s knowledge, threatened action, suit, proceeding or claim by others challenging the rights of the Company or its subsidiaries in or to any such Intellectual Property, and the Company is unaware of any facts which it believes would form a reasonable basis for a successful challenge to the rights in such Intellectual Property, in each case that would have a Material Adverse Effect; (iv) the Intellectual Property owned by the Company and its subsidiaries and, to the Company’s knowledge, the Intellectual Property licensed to the Company and its subsidiaries have not been adjudged invalid or unenforceable, in whole or in part, and there is no pending or, to the Company’s knowledge, threatened action, suit, proceeding or claim by others challenging the validity or scope of any such Intellectual Property, and the Company is unaware of any facts which it believes would form a

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reasonable basis for a successful challenge to the validity, enforceability or scope of such Intellectual Property, in each case that would have a Material Adverse Effect; (v) none of the technology employed by the Company has been obtained or is being used by the Company in material violation of any contractual obligation binding on the Company or, to the Company’s knowledge, upon any of its officers, directors or employees or otherwise in violation of the rights of any persons; (vi) to the Company’s knowledge, there are no third parties who have or will be able to establish rights to any Intellectual Property described in the Registration Statement, the Pricing Disclosure Package and the Prospectus as owned or exclusively licensed by the Company or its subsidiaries that would have a Material Adverse Effect except for licenses granted in writing by the Company or its subsidiaries to any third parties; (vii) the Company is not a party to or bound by any options, licenses or other agreements, with respect to the Company’s or a third party’s Intellectual Property, that are required to be set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus, and that are not described in all material respects therein; (viii) to the Company’s knowledge, there is no patent or patent application that contains claims that interfere (as such term is described in 35 U.S.C. §135 and 37 C.F.R. 41.100 to 41.208) with the issued or pending claims of any of the Intellectual Property that would a Material Adverse Effect on the Company; and (ix) to the Company’s knowledge, there is no prior art material to any patent or patent application owned or exclusively licensed by the Company that has not been disclosed to the U.S. Patent and Trademark Office that would have a Material Adverse Effect.

(x)     Healthcare Compliance . Except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the Company: (i) is and at all times during the past three years has been in material compliance with all applicable laws, rules or regulations, including, without limitation, the federal Anti-Kickback Statute (42 U.S.C. § 1320a-7b(b)), the Civil Monetary Penalties Laws (42 U.S.C. § 1320a-7a), the civil False Claims Act (31 U.S.C. §§ 3729 et seq.), the administrative False Claims Law (42 U.S.C. § 1320a-7b(a)), the Physician Payments Sunshine Act (42 U.S.C. § 1320-7h), all criminal laws relating to health care fraud and abuse, including, but not limited to, 18 U.S.C. §§ 286 and 287, the Health Insurance Portability and Accountability Act of 1996 (42 U.S.C. § 1320d et seq.), 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 Federal Food, Drug and Cosmetic Act (21 U.S.C. §§ 301 et seq.) (the “FFDCA”), Medicare (Title XVIII of the Social Security Act), Medicaid (Title XIX of the Social Security Act), the collection and reporting requirements, and the processing of any applicable rebate, chargeback or adjustment, under applicable rules and regulations relating to the Medicaid Drug Rebate Program (42 U.S.C. § 1396r-8) and any state supplemental rebate program, Medicare average sales price reporting (42 U.S.C. § 1395w-3a), the Public Health Service Act (42 U.S.C. § 256b), the VA Federal Supply Schedule (38 U.S.C. § 8126) or under any state pharmaceutical assistance program or U.S. Department of Veterans Affairs agreement, and any successor government programs, each as amended, the regulations promulgated pursuant to such laws, any other similar local, state or federal law, and all applicable laws, rules or regulations of the U.S. Food and Drug Administration (“FDA”) and other comparable regulatory authorities (“Governmental Authority”) relating to the ownership, testing, development, manufacture, packaging, use, distribution, marketing, labeling, storage, import, export or disposal of any product under clinical development or manufactured by or on behalf of the Company (collectively, the “Applicable Laws”); (ii) has not received any FDA Form 483, notice of adverse finding, warning letter, untitled letter or other correspondence or notice from the FDA or any Governmental Authority alleging or asserting material noncompliance with any Applicable Laws or any licenses, certificates, approvals, clearances, exemptions, authorizations, permits and supplements or amendments thereto required by any such Applicable Laws (“Authorizations”); (iii) possesses all required material Authorizations and such Authorizations are valid and in full

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force and effect and the Company is not in material violation of any term of any such Authorizations; (iv) has not received notice of any claim, action, suit, proceeding, hearing, enforcement, investigation, arbitration or other action from the FDA or any Governmental Authority or third party alleging that any product, operation or activity is in material violation of any Applicable Laws or Authorizations; (v) has not received notice that the FDA or any Governmental Authority has taken, is taking or intends to take action to limit, suspend, modify or revoke any material Authorizations; (vi) has filed, obtained, maintained or submitted all material reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments as required by any Applicable Laws or Authorizations and that all such reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments were materially complete and correct on the date filed (or were corrected or supplemented by a subsequent submission); and (vii) is not a party to or has any ongoing reporting obligations pursuant to any corporate integrity agreement, deferred prosecution agreement, monitoring agreement, consent decree, settlement order, plan of correction or similar agreement imposed by any governmental authority. To the knowledge of the Company, all third parties that are collaborating with the Company with respect to the clinical development or manufacture of companion diagnostics are in material compliance with all Applicable Laws and possess all required material Authorizations relating to such companion diagnostics being developed in collaboration with the Company. Additionally, neither the Company, nor any of its officers or directors, nor, to the Company’s knowledge, any of its employees, has been excluded, suspended or debarred from participation in any U.S. state or federal healthcare program or human clinical research or, except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, is subject to a governmental inquiry, investigation, proceeding, or other any other similar action that could reasonably be expected to result in debarment, suspension, or exclusion of such person.

(y)     Clinical Studies . The studies, tests and preclinical and clinical trials conducted by or, to the Company’s knowledge, on behalf of the Company or by third parties, were and, if still ongoing, are being conducted in all material respects in accordance with experimental protocols, procedures and controls pursuant to all Authorizations and Applicable Laws, including, without limitation, the FFDCA; the descriptions of the results of such studies, tests and trials contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus are, to the Company’s knowledge, accurate and complete in all material respects and fairly present in all material respects the data derived from such studies, tests and trials; except to the extent disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the Company is not aware of any studies, tests or trials, the results of which the Company believes would have an adverse effect on the development of the Company’s product candidates in the Registration Statement, the Pricing Disclosure Package and the Prospectus; and, except to the extent disclosed in the Registration Statement, the Pricing Disclosure Package or the Prospectus, the Company has not received any written notices or correspondence from the FDA or any Governmental Authority requiring the termination or suspension of any studies, tests or preclinical or clinical trials conducted by or on behalf of the Company.

(z)     No Undisclosed Relationships . 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 Securities Act to be described in the Registration Statement and the Prospectus and that is not so described in the Registration Statement, the Prospectus and the Pricing Disclosure Package.

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(aa)     Investment Company Act . The Company is not and, after giving effect to the offering and sale of the Shares and the application of the proceeds thereof as described in the Pricing Disclosure Package and the Prospectus, will not be required to register as an “investment company” or an entity “controlled” by 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”).

(bb)     Taxes. The Company and its subsidiaries have paid all federal, state, local and foreign taxes required to be paid and filed all tax returns required to be filed through the date hereof; and except as otherwise disclosed in the Registration Statement, the Pricing Disclosure Package and the 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, except where failure to pay or file, or where such deficiency, would in any case not, individually or in the aggregate, have a Material Adverse Effect.

(cc)     Licenses and Permits. The Company and its subsidiaries possess all licenses, sub-licenses, certificates, permits and other authorizations issued by, and have made all declarations and filings with, the appropriate federal, state, local or foreign governmental or regulatory authorities that are necessary for the ownership or lease of their respective properties or the conduct of their respective businesses as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus (collectively, “Licenses”), except where the failure to possess or make the same would not, individually or in the aggregate, have a Material Adverse Effect; and except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, neither the Company nor any of its subsidiaries has received notice of any revocation or modification of any such License or has any reason to believe that any such License will not be renewed in the ordinary course. To the Company’s knowledge, no party granting any such Licenses has taken any action to limit, suspend or revoke the same in any material respect.

(dd)     No Labor Disputes. 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 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.

(ee)     Compliance With Environmental Laws. (i) The Company and its subsidiaries (a) are, and at all times during the past three years were, in compliance with any and all applicable federal, state, local and foreign laws, rules, regulations, requirements, decisions, judgments, decrees and orders relating to pollution or the protection of the environment, natural resources or human health or safety, including those relating to the generation, storage, treatment, use, handling, transportation, Release or threat of Release of Hazardous Materials (collectively, “Environmental Laws”), (b) have received and are in compliance with all permits, licenses, certificates or other authorizations or approvals required of them under applicable Environmental Laws to conduct their respective businesses, (c) have not received notice of any actual or potential liability under or relating to, or actual or potential violation of, any Environmental Laws, including for the investigation or remediation of any Release or threat of Release of Hazardous Materials, and have no knowledge of any event or condition that would reasonably be expected to result in any such notice, (d) are not conducting or paying for, in whole or in part, any investigation, remediation or other corrective action pursuant to any Environmental Law at any

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location, and (e) are not a party to any order, decree or agreement that imposes any obligation or liability under any Environmental Law, 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 Pricing Disclosure Package and the Prospectus, (a) there are no proceedings that are pending, or that are known by the Company to be 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 proceedings regarding which it is reasonably believed no monetary sanctions of $100,000 or more will be imposed, (b) the Company and its subsidiaries are not aware of any facts or issues regarding the Company’s or its subsidiaries’ compliance with Environmental Laws, or liabilities or other obligations under Environmental Laws, including the Release or threat of Release of Hazardous Materials, that would reasonably be expected to have a material effect on the capital expenditures, earnings or competitive position of the Company and its subsidiaries, and (c) none of the Company and its subsidiaries anticipates material capital expenditures relating to any Environmental Laws.

(ff)     Hazardous Materials . There has been no storage, generation, transportation, use, handling, treatment, Release or threat of Release of Hazardous Materials by, relating to or caused by the Company or any of its subsidiaries (or, to the knowledge of the Company and its subsidiaries, any other entity (including any predecessor) for whose acts or omissions the Company or any of its subsidiaries is or would reasonably be expected to be liable) at, on, under or from any property or facility now or previously owned, operated or leased by the Company or any of its subsidiaries, or at, on, under or from any other property or facility, in violation of any Environmental Laws or in a manner or amount or to a location that would reasonably be expected to result in any liability under any Environmental Law, except for any violation or liability which would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. “Hazardous Materials” means any material, chemical, substance, waste, pollutant, contaminant, compound, mixture, or constituent thereof, in any form or amount, including petroleum (including crude oil or any fraction thereof) and petroleum products, natural gas liquids, asbestos and asbestos containing materials, naturally occurring radioactive materials, brine, and drilling mud, regulated by a governmental agency or which can give rise to liability under any Environmental Law. “Release” means any spilling, leaking, seepage, pumping, pouring, emitting, emptying, discharging, injecting, escaping, leaching, dumping, disposing, depositing, dispersing, or migrating in, into or through the environment, or in, into from or through any building or structure.

(gg)     Compliance with ERISA. Except as would not reasonably be expected to have a Material Adverse Effect: (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 of its subsidiaries has 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 Internal Revenue Code of 1986, as amended (the “Code”); (ii) to the Company’s knowledge, 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, the minimum funding standard of Section 412 of the Code or Section 302 of ERISA, as applicable, has been satisfied (without taking into account any waiver thereof or extension of any amortization period) and is reasonably expected to be satisfied in the future (without taking into account any waiver thereof or extension of any amortization period); (iv) no “reportable event”

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(within the meaning of Section 4043(c) of ERISA) has occurred or is reasonably expected to occur that either has resulted, or would reasonably be expected to result, in liability to the Company or its subsidiaries; (v) neither the Company nor any member of the “Controlled Group” (defined as any organization which is a member of a controlled group of corporations within the meaning of Section 414 of the Code) 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 Guaranty Corporation (the “PBGC”)) in respect of a Plan; and (vi) to the knowledge of the Company, there is no pending audit or investigation by the Internal Revenue Service, the U.S. Department of Labor, the PBGC or any other governmental agency or any foreign regulatory agency with respect to any Plan. None of the following events has occurred: (x) a material increase in the aggregate amount of contributions required to be made to all Plans subject to Title IV of ERISA by the Company or its subsidiaries in the current fiscal year of the Company and its subsidiaries compared to the amount of such contributions made in the Company and its subsidiaries’ most recently completed fiscal year; or (y) a material increase in the Company and its subsidiaries’ “accumulated post-retirement benefit obligations” (within the meaning of Statement of Financial Accounting Standards 106) compared to the amount of such obligations in the Company and its subsidiaries’ most recently completed fiscal year.

(hh)     Disclosure Controls . The Company and its subsidiaries maintain a 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 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.

(ii)     Accounting Controls. 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 U.S. generally accepted accounting principles. The Company and its subsidiaries maintain a system of 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 U.S. generally accepted accounting principles and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; (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 and (v) interactive data in eXtensible Business Reporting Language incorporated by reference in the Registration Statement, the Prospectus and the Pricing Disclosure Package fairly presents the information called for in all material respects and is prepared in accordance with the Commission’s rules and guidelines applicable thereto. Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are no material weaknesses in the Company’s internal controls over financial reporting. The Company’s auditors and the Audit Committee of the Board of Directors of the Company have been advised of: (i) any significant deficiencies and material weaknesses in the design or operation of internal controls

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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) 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.

(jj)     eXtensible Business Reporting Language. The interactive data in eXtensible Business Reporting Language incorporated by reference in the Registration Statement 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.

(kk)     Insurance. The Company and its subsidiaries have insurance covering their respective properties, operations, personnel and businesses, which insurance is in amounts and insures against such losses and risks as 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) any reason to believe that it will not be able 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.

(ll)     No Unlawful Payments. Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee, affiliate or other person associated with or acting on behalf of the Company or any of its subsidiaries has (i) used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity; (ii) 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) 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 committed an offence under the Bribery Act 2010 of the United Kingdom or any other applicable anti-bribery or anti-corruption law; or (iv) 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, in each case, prohibited by applicable law. The Company and its subsidiaries have instituted, maintain and enforce policies and procedures designed to promote and ensure compliance with all applicable anti-bribery and anti-corruption laws.

(mm)     Compliance with Anti-Money Laundering Laws . The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements, 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 issued, administered or enforced by any governmental or regulatory agency (collectively, the “Anti-Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental or regulatory 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.

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(nn) No Conflicts with Sanctions Laws. Neither the Company nor any of its subsidiaries, directors or officers, nor, to the knowledge of the Company, any employees, agents, affiliates or other person associated with or acting on behalf of the Company or any of its subsidiaries is 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 is the Company or any of its subsidiaries located, organized or resident in a country or territory that is the subject or target of comprehensive (rather than list-based) Sanctions, including, without limitation, Cuba, Iran, North Korea, Sudan, Syria and Crimea (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 (5) years, (i) the Company and its subsidiaries (other than Clovis Italy and its subsidiaries) have not knowingly engaged in and are not now knowingly engaged in any transactions with any person that at the time of the transaction is or was the subject of Sanctions, (ii) Clovis Italy and its subsidiaries since the date of their acquisition by the Company 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 transaction is or was the subject or the target of Sanctions or with any Sanctioned Country and (iii) prior to the date of their acquisition by the Company, to the knowledge of the Company, neither Clovis Italy nor its subsidiaries knowingly engaged in any 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.

(oo) No Restrictions on Subsidiaries . Subject to any restrictions under applicable law, 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.

(pp) No Broker’s Fees. Neither the Company nor any of its subsidiaries is a party to any contract, agreement or understanding with any person (other than this Agreement) that would give rise to a valid claim against the Company or any of its subsidiaries or any Underwriter for a brokerage commission, finder’s fee or like payment in connection with the offering and sale of the Shares.

(qq) No Registration Rights . Except as described in or expressly contemplated by the Registration Statement, the Pricing Disclosure Package and the Prospectus, no person has the right to require the Company or any of its subsidiaries to register any securities for sale under the Securities Act by reason of the filing of the Registration Statement with the Commission or the issuance and sale of the Shares by the Company, which such right has not been waived.

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(rr) No Stabilization. The Company has not taken, directly or indirectly, any action designed to or that would reasonably be expected to cause or result in any stabilization or manipulation of the price of the Shares.

(ss) Margin Rules . 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 Pricing Disclosure Package and the 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.

(tt) Forward-Looking Statements . No forward looking statement (within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act) included or incorporated by reference in any of the Registration Statement, the Pricing Disclosure Package or the Prospectus has been made or reaffirmed without a reasonable basis or has been disclosed other than in good faith.

(uu) Statistical and Market Data. Nothing has come to the attention of the Company that has caused the Company to believe that the statistical and market-related data included or incorporated by reference in each of the Registration Statement, the Pricing Disclosure Package and the Prospectus is not based on or derived from sources that are reliable and accurate in all material respects.

(vv) Sarbanes-Oxley Act . 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 applicable provision of the Sarbanes-Oxley Act of 2002, as amended, 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.

(ww) Status under the Securities Act . At the time of filing the Registration Statement and any post-effective amendment thereto, at the earliest time thereafter that the Company or any offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) under the Securities Act) of the Shares and at the date hereof, the Company was not and is not an “ineligible issuer,” and was and is a “well-known seasoned issuer,” in each case as defined in Rule 405 under the Securities Act.

(xx) Accurate Disclosure . The statements included or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus, as applicable, under the headings “Risk Factors – Reimbursement may be limited or unavailable in certain market segments for our product candidates, which could make it difficult for us to sell our products profitably,” “Risk Factors – The patent protection and patent prosecution for some of our product candidates is dependent on third parties,” “Business – License Agreements,” “Business – Government Regulation,” “Business – Patents and Proprietary Rights,” “Description of Capital Stock,” “Material U.S. Federal Income and Estate Tax Considerations” and “Underwriting” insofar as such statements summarize legal matters, agreements, documents or proceedings discussed therein, are accurate and fair summaries in all material respects of such legal matters, agreements, documents or proceedings and present the information required to be shown.

(yy) No Ratings. There are (and prior to the Closing Date, will be) no debt securities or preferred stock issued or guaranteed by the Company or any of its subsidiaries that are rated by a “nationally recognized statistical rating organization,” as such term is defined in Section 3(a)(62) in the Exchange Act.

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4. Further Agreements of the Company . The Company covenants and agrees with each Underwriter that:

(a) Required Filings. The Company will file the Prospectus with the Commission within the time periods specified by Rule 424(b) and Rule 430A, 430B or 430C under the Securities Act, will file any Issuer Free Writing Prospectus (including the term sheet substantially in the form of Annex C hereto) to the extent required by Rule 433 under the Securities Act; will file within the applicable time period required by the Exchange Act all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus and for so long as the delivery of a prospectus is required in connection with the offering or sale of the Shares; and the Company will furnish copies of the Prospectus and each Issuer Free Writing Prospectus (to the extent not previously delivered) to the Underwriters in New York City prior to 10:00 A.M., New York City time, as soon as practicable but in no event later than the second business day next succeeding the date of this Agreement, in such quantities as the Underwriters may reasonably request. The Company will pay the registration fee for this offering of the Shares within the time period required by Rule 456(b)(1) under the Securities Act (without giving effect to the proviso therein) and in any event prior to the Closing Date.

(b) Delivery of Copies. The Company will deliver to the Underwriters, without charge, (i) two signed copies of the Registration Statement as originally filed and each amendment thereto, in each case including all exhibits and consents filed therewith and (ii) during the Prospectus Delivery Period (as defined below), as many copies of the Prospectus (including all amendments and supplements thereto and documents incorporated by reference therein and each Issuer Free Writing Prospectus) as the Underwriters may reasonably request. As used herein, the term “Prospectus Delivery Period” means such period of time after the first date of the public offering of the Shares as in the opinion of counsel for the Underwriters a prospectus relating to the Shares is required by law to be delivered (or required to be delivered but for Rule 172 under the Securities Act) in connection with sales of the Shares by any Underwriter or dealer.

(c) Amendments or Supplements, Issuer Free Writing Prospectus and Exchange Act Documents. During the Prospectus Delivery Period, before using, authorizing, approving, referring to or filing any Issuer Free Writing Prospectus, and before filing any amendment or supplement to the Registration Statement or the Prospectus, the Company will furnish to the Underwriters and counsel for the Underwriters a copy of the proposed Issuer Free Writing Prospectus, amendment or supplement for review and will not use, authorize, approve, refer to or file any such Issuer Free Writing Prospectus or file any such proposed amendment or supplement to which the Underwriters reasonably object. The Company will furnish to the Underwriters and counsel for the Underwriters notice of its intention to make any filings pursuant to the Exchange Act or the Exchange Act Regulations from the Applicable Time to the Closing Date and will furnish to the Underwriters and counsel for the Underwriters a copy of any such document a reasonable amount of time prior to such proposed filing and work in good faith with the Underwriters and counsel for the Underwriters to determine the requirement, form and content of any such document and accept all reasonable comments thereto from the Underwriters.

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(d) Notice to the Underwriters. During the Prospectus Delivery Period, the Company will advise the Underwriters promptly, and confirm such advice in writing (which advice may be delivered via electronic mail), (i) when any amendment to the Registration Statement has been filed or becomes effective; (ii) when any supplement to the Prospectus or any Issuer Free Writing Prospectus or any amendment to the Prospectus has been filed or distributed; (iii) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus or the receipt of any comments from the Commission relating to the Registration Statement or any other request by the Commission for any additional information; (iv) of the issuance by the Commission of any order suspending the effectiveness of the Registration Statement or preventing or suspending the use of any Preliminary Prospectus included in the Pricing Disclosure Package, any of the Pricing Disclosure Package or the Prospectus or the initiation or, to the Company’s knowledge, threatening of any proceeding for that purpose or pursuant to Section 8A of the Securities Act; (v) of the occurrence of any event within the Prospectus Delivery Period as a result of which the Prospectus, the Pricing Disclosure Package or any Issuer Free Writing Prospectus as then amended or supplemented would contain any 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 existing when the Prospectus, the Pricing Disclosure Package or any such Issuer Free Writing Prospectus is delivered to a purchaser, not misleading; (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 pursuant to Rule 401(g)(2) under the Securities Act; and (vii) of the receipt by the Company of any notice with respect to any suspension of the qualification of the Shares for offer and sale in any jurisdiction or the initiation or, to the Company’s knowledge, threatening of any proceeding for such purpose; and the Company will use its reasonable best efforts to prevent the issuance of any such order suspending the effectiveness of the Registration Statement, preventing or suspending the use of any Preliminary Prospectus, any of the Pricing Disclosure Package or the Prospectus or suspending any such qualification of the Shares and, if any such order is issued, will use its reasonable best efforts to obtain as soon as possible the withdrawal thereof.

(e) Ongoing Compliance. (1) If during the Prospectus Delivery Period (i) any event or development shall occur or condition shall exist as a result of which the Prospectus as then amended or supplemented would contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Prospectus to comply with law, the Company will promptly notify the Underwriters thereof and promptly prepare and, subject to paragraph (c) above, file with the Commission and furnish to the Underwriters and to such dealers as the Underwriters may designate such amendments or supplements to the Prospectus as may be necessary so that the statements in the Prospectus as so amended or supplemented will not, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, be misleading or so that the Prospectus will comply with law and (2) if at any time prior to the Closing Date (i) any event or development shall occur or condition shall exist as a result of which the Pricing Disclosure Package as then amended or supplemented would contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances existing when the Pricing Disclosure Package is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Pricing Disclosure Package to comply with law, the Company will promptly notify the Underwriters thereof and promptly prepare and, subject to paragraph (c) above, file with the Commission (to the extent required) and furnish to the Underwriters and to such dealers as the Underwriters may designate such amendments or supplements to the Pricing Disclosure Package as may be necessary so that the statements in the Pricing Disclosure Package as so amended or supplemented will not, in the light of the circumstances existing when the Pricing Disclosure Package is delivered to a purchaser, be misleading or so that the Pricing Disclosure Package will comply with law.

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(f) Blue Sky Compliance. The Company will qualify the Shares for offer and sale under the securities or Blue Sky laws of such jurisdictions as the Underwriters shall reasonably request and will continue such qualifications in effect so long as required for distribution of the Shares; provided that the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file any general consent to service of process in any such jurisdiction or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

(g) Earning Statement. The Company will make generally available to its security holders and the Underwriters as soon as practicable an earnings statement that satisfies the provisions of Section 11(a) of the Securities Act and Rule 158 of the Commission promulgated thereunder covering a period of at least twelve months beginning with the first fiscal quarter of the Company occurring after the “effective date” (as defined in Rule 158) of the Registration Statement, provided, however, that (1) such requirements to the Company’s security holders shall be deemed met by the Company’s compliance with its reporting requirements pursuant to the Exchange Act if such compliance satisfies the conditions of Rule 158 and (2) such requirements to the Underwriters shall be deemed met by the Company if the related reports are available on the Commission’s Electronic Data Gathering, Analysis and Retrieval System or any successor system.

(h) Clear Market. For a period of 60 days after the date of the Prospectus, the Company will not (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, or otherwise transfer or dispose of, directly or indirectly, or file with the Commission a registration statement under the Securities Act relating to, any shares of Stock or any securities convertible into or exercisable or exchangeable for Stock, or publicly disclose the intention to make any offer, sale, pledge, disposition or filing, or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Stock or any such other securities, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Stock or such other securities, in cash or otherwise, without the prior written consent of J.P. Morgan Securities LLC, other than (A) the Shares to be sold hereunder, (B) the 1.25% convertible senior notes due 2025 (the “Notes”) to be sold pursuant to that certain Underwriting Agreement, dated as of the date hereof, by and among the Company and the Underwriters, or the issuance of shares of Common Stock upon conversion of the Notes, (C) options to purchase Common Stock or other equity awards granted under the Company Stock Plans, provided that such options to purchase Common Stock or other equity awards (other than with respect to annual grants to directors) do not vest during the 60-day restricted period and do not exceed 5% of the outstanding shares of Common Stock following the consummation of the offering of the Shares, or any shares of Stock of the Company issued upon the exercise of options or other equity awards granted under Company Stock Plans, (D) the filing by the Company of any registration statement on Form S-8 or a successor form thereto relating to any shares of Common Stock granted under any Company Stock Plan, (E) the issuance of securities in connection with the acquisition by the Company of the securities, business, property or other assets (other than the in-license of a single product candidate, which shall be subject to clause (F) below) of another person or entity, or pursuant to any employee benefit plans assumed by the Company in connection with any such acquisition or (F) the issuance of securities in connection with joint ventures, commercial relationships or other strategic transactions, provided that in the case of (F), prior to any issuance the Company shall cause each recipient of such securities to execute and deliver to the Underwriters a Lock-up Agreement substantially in the form of Exhibit A and provided further that any issuances pursuant to clauses (E) and (F) above shall not, in the aggregate, exceed 5% of the outstanding shares of Common Stock on the date hereof.

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(i) Use of Proceeds. The Company will apply the net proceeds from the sale of the Shares as described in the Pricing Disclosure Package and the Prospectus under the heading “Use of Proceeds.”

(j) No Stabilization. The Company will not take, directly or indirectly, any action designed to or that would reasonably be expected to cause or result in any stabilization or manipulation of the price of the Stock.

(k) Exchange Listing. The Company will use its reasonable best efforts to list for quotation the Shares on the Nasdaq Market.

(l) Reports. During the period commencing on the Closing Date and ending on the earlier of (1) when the Shares cease to be outstanding or (2) the third anniversary of the Closing Date, the Company will furnish to the Underwriters, as soon as they are available, copies of all reports or other communications (financial or other) furnished by the Company to holders of the Shares, and copies of any reports and financial statements furnished to or filed by the Company with the Commission or any national securities exchange or automatic quotation system; provided the Company will be deemed to have furnished such reports and financial statements to the Underwriters to the extent they are filed on the Commission’s Electronic Data Gathering, Analysis, and Retrieval system or any successor system.

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

5. Certain Agreements of the Underwriters . Each Underwriter hereby represents to the Company and agrees with the Company that:

(a) It has not used, authorized use of, referred to or participated in the planning for use of, and will not use, authorize use of, refer to or participate in the planning for use of, any “free writing prospectus,” as defined in Rule 405 under the Securities Act (which term includes use of any written information furnished to the Commission by the Company and not incorporated by reference into the Registration Statement and any press release issued by the Company) other than (i) a free writing prospectus that contains no “issuer information” (as defined in Rule 433(h)(2) under the Securities Act) that was not included (including through incorporation by reference) in the Preliminary Prospectus included in the Pricing Disclosure Package or a previously filed Issuer Free Writing Prospectus, (ii) any Issuer Free Writing Prospectus listed on Annex B or prepared pursuant to Section 3(c) or Section 4(c) above (including any electronic road show), or (iii) any free writing prospectus prepared by such underwriter and approved by the Company in advance in writing (each such free writing prospectus referred to in clauses (i) or (iii), an “Underwriter Free Writing Prospectus”).

(b) It has not and will not, without the prior written consent of the Company, use any free writing prospectus that contains the final terms of the Shares unless such terms have previously been included in a free writing prospectus filed with the Commission; provided that Underwriters may use the term sheet substantially in the form of Annex C hereto without the consent of the Company; provided further that any Underwriter using such term sheet shall notify the Company, and provide a copy of such term sheet to the Company, prior to, or substantially concurrently with, the first use of such term sheet.

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(c) It is not subject to any pending proceeding under Section 8A of the Securities Act with respect to the offering (and will promptly notify the Company if any such proceeding against it is initiated during the Prospectus Delivery Period).

6. Conditions of Underwriters’ Obligations. The obligation of each Underwriter to purchase the Underwritten Shares on the Closing Date or the Option Shares on the Additional Closing Date, as the case may be, as provided herein is subject to the performance by the Company of its covenants and other obligations hereunder and to the following additional conditions:

(a) Registration Compliance; No Stop Order. No order suspending the effectiveness of the Registration Statement shall be in effect, and no proceeding for such purpose, pursuant to Rule 401(g)(2) or pursuant to Section 8A under the Securities Act shall be pending before or threatened by the Commission; the Prospectus and each Issuer Free Writing Prospectus shall have been timely filed with the Commission under the Securities Act (in the case of an Issuer Free Writing Prospectus, to the extent required by Rule 433 under the Securities Act) and in accordance with Section 4(a) hereof; and all requests by the Commission for additional information shall have been complied with to the reasonable satisfaction of the Underwriters.

(b) Representations and Warranties. The representations and warranties of the Company contained herein shall be true and correct on the date hereof and on and as of the Closing Date or the Additional Closing Date, as the case may be; and the statements of the Company and its officers made on behalf of the Company in any certificates delivered pursuant to this Agreement shall be true and correct on and as of the Closing Date or the Additional Closing Date, as the case may be.

(c) No Material Adverse Change. No event or condition of a type described in Section 3(g) hereof shall have occurred or shall exist, which event or condition is not described in the Pricing Disclosure Package (excluding any amendment or supplement thereto) and the Prospectus (excluding any amendment or supplement thereto) and the effect of which in the judgment of the Underwriters makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Shares on the Closing Date or the Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Pricing Disclosure Package and the Prospectus.

(d) Officer’s Certificate. The Underwriters shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, a certificate on behalf of the Company of the chief financial officer or chief accounting officer of the Company and one additional senior executive officer of the Company who is reasonably satisfactory to the Underwriters (provided that the chief executive officer of the Company shall be deemed satisfactory) (i) confirming that such officers have carefully reviewed the Registration Statement, the Pricing Disclosure Package and the Prospectus and, to the knowledge of such officers, the representations of the Company set forth in Sections 3(b) and 3(d) hereof are true and correct, (ii) confirming that the other representations and warranties of the Company in this Agreement are true and correct and that the Company has complied with all agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date or the Additional Closing Date, as the case may be, and (iii) to the effect set forth in paragraphs (a) and (c) above.

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(e) Comfort Letters. On the date of this Agreement and on the Closing Date or the Additional Closing Date, as the case may be, Ernst & Young LLP shall have furnished to the Underwriters, at the request of the Company, letters, dated the respective dates of delivery thereof and addressed to the Underwriters, in form and substance reasonably satisfactory to the Underwriters, containing statements and information of the type customarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus; provided, that the letter delivered on the Closing Date or the Additional Closing Date, as the case may be, shall use a “cut-off” date no more than three business days prior to such Closing Date or such Additional Closing Date, as the case may be.

(f) Opinion and Negative Assurance Letter of Counsel for the Company. Willkie Farr & Gallagher LLP, counsel for the Company, shall have furnished to the Underwriters, at the request of the Company, their written opinion and negative assurance letter, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Underwriters, in the form set forth in Annex A-1 hereto.

(g) [Intentionally omitted].

(h) Opinion of Intellectual Property Counsel for the Company. Swanson & Bratschun, L.L.C., intellectual property counsel for the Company, shall have furnished to the Underwriters, at the request of the Company, their written opinion, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Underwriters, in the form set forth in Annex A-2 hereto.

(i) Opinion and Negative Assurance Letter of Counsel for the Underwriters. The Underwriters shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, an opinion and negative assurance letter of Latham & Watkins LLP, counsel for the Underwriters, with respect to such matters as the Underwriters may reasonably request, and such counsel shall have received such documents and information as they may reasonably request to enable them to pass upon such matters.

(j) No Legal Impediment to Issuance. 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 Closing Date or the Additional Closing Date, as the case may be, prevent the issuance or sale of the Shares; and no injunction or order of any federal, state or foreign court shall have been issued that would, as of the Closing Date or the Additional Closing Date, as the case may be, prevent the issuance or sale of the Shares.

(k) Good Standing . The Underwriters shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, satisfactory evidence of the good standing (where such concept is recognized) of the Company and its subsidiaries in their respective jurisdictions of organization and their good standing as foreign entities in the jurisdictions set forth on Annex C hereto, in each case in writing or any standard form of telecommunication from the appropriate governmental authorities of such jurisdictions.

(l) Exchange Listing. The Shares to be delivered on the Closing Date or Additional Closing Date, as the case may be, shall have been approved for listing on the Nasdaq Market, subject to official notice of issuance.

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(m) Lock-up Agreements . The “lock-up” agreements, each substantially in the form of Exhibit A hereto, between you and the executive officers and directors of the Company relating to sales and certain other dispositions of shares of Stock or certain other securities, delivered to you on or before the date hereof, shall be full force and effect on the Closing Date or Additional Closing Date, as the case may be.

(n) Additional Documents. On or prior to the Closing Date or the Additional Closing Date, as the case may be, the Company shall have furnished to the Underwriters such further certificates and documents as the Underwriters may reasonably request.

All letters, certificates and evidence mentioned above or elsewhere in this Agreement shall be deemed to be in compliance with the provisions hereof only if they are in form and substance reasonably satisfactory to counsel for the Underwriters.

7. Indemnification and Contribution .

(a) Indemnification of the Underwriters. The Company agrees to indemnify and hold harmless each Underwriter, its directors and officers, those of its affiliates that have assisted in the distribution of the Shares hereunder and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, reasonable legal fees and other expenses incurred in connection with any suit, action or proceeding or any claim asserted, as such reasonable fees and expenses are incurred), joint or several, 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 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 Issuer Free Writing Prospectus, any “issuer information” filed or required to be filed pursuant to Rule 433(d) under the Securities Act or any Pricing Disclosure Package (including any Pricing Disclosure Package that has subsequently been amended), 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 furnished to the Company in writing by such Underwriter expressly for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in subsection (b) below.

(b) Indemnification of the Company. Each Underwriter 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 Securities 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 furnished to the Company in writing by such Underwriter expressly for use in the Registration Statement, the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus or any Pricing Disclosure Package, it being understood and agreed upon that the only such information furnished by any Underwriter consists of the following information in the Prospectus furnished on behalf of each Underwriter: the concession figure appearing in the third paragraph under the caption “Underwriting” and the information contained in the seventh, twelfth and thirteenth paragraphs, the last two sentences of the fourteenth paragraph, and the fifteenth paragraph under the caption “Underwriting.”

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(c) Notice and Procedures. 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 paragraph (a) or (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 paragraph (a) or (b) above 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 paragraph (a) or (b) above. 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 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) in the opinion of counsel to the Indemnified Person there may be legal defenses available to the Indemnified Person 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) include 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 interest between them. It is understood and agreed that the Indemnifying Person shall not, in connection with any proceeding or related proceedings 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 all Indemnified Persons, and that all such reasonable fees and expenses shall be paid or reimbursed as they are incurred. Any such separate firm for any Underwriter, its affiliates, directors and officers and any control persons of such Underwriter shall be designated in writing by the Underwriters and any such separate firm for the Company, its directors, its officers who signed the Registration Statement and any control persons of the Company 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. Notwithstanding the foregoing sentence, if at any time an Indemnified Person shall have requested that an Indemnifying Person reimburse the Indemnified Person for fees and expenses of counsel as contemplated by this paragraph, the Indemnifying Person shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 45 days after receipt by the Indemnifying Person of such request and (ii) the Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement. 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 would have been a party and indemnification would 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.

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(d) Contribution. If the indemnification provided for in paragraphs (a) and (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 paragraph, 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 Underwriters on the other, from the offering of the Shares 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 Underwriters 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 Underwriters on the other, shall be deemed to be in the same respective proportions as the net proceeds (before deducting expenses but after deducting underwriting discounts and commissions) received by the Company from the sale of the Shares and the total underwriting discounts and commissions received by the Underwriters in connection therewith, in each case as set forth in the table on the cover of the Prospectus, bear to the aggregate offering price of the Shares. The relative fault of the Company, on the one hand, and the Underwriters, 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 or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

(e) Limitation on Liability. The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to paragraph (d) above were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take account of the equitable considerations referred to in paragraph (d) above. The amount paid or payable by an Indemnified Person as a result of the losses, claims, damages and liabilities referred to in paragraph (d) above shall be deemed to include, subject to the limitations set forth above, any legal or other expenses, in each case, reasonably incurred by such Indemnified Person in connection with any such action or claim. Notwithstanding the provisions of paragraphs (d) and (e), in no event shall an Underwriter be required to contribute any amount in excess of the amount by which the total underwriting discounts and commissions received by such Underwriter with respect to the offering of the Shares exceeds the amount of any damages that such Underwriter 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 Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations to contribute pursuant to paragraphs (d) and (e) are several in proportion to their respective purchase obligations hereunder and not joint.

(f) Non-Exclusive Remedies. The remedies provided for in paragraphs (a) through (e) 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.

8. Effectiveness of Agreement . This Agreement shall become effective upon the execution and delivery hereof by the parties hereto.

9. Termination . This Agreement may be terminated in the absolute discretion of the Underwriters, by notice to the Company, if after the execution and delivery of this Agreement and on or prior to the Closing Date or, in the case of the Option Shares, prior to the Additional Closing Date: (i) trading generally shall have been suspended or materially limited on or by any of the New York Stock Exchange or the Nasdaq Market; (ii) trading of any securities issued or guaranteed by the Company shall

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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 major disruption of settlements of securities, payment, or clearance services in the United States or any other country where such securities are listed or (v) 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, in the judgment of the Underwriters, is material and adverse and makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Shares on the Closing Date or the Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Pricing Disclosure Package and the Prospectus. In the event this Agreement is terminated, the Underwriters shall contemporaneously terminate or waive in their entirety the lock-up agreements referred to in Section 6(m).

10. Defaulting Underwriter .

(a) If, on the Closing Date or the Additional Closing Date, as the case may be, any Underwriter defaults on its obligation to purchase the Shares that it has agreed to purchase hereunder on such date, the non-defaulting Underwriters may in their discretion arrange for the purchase of such Shares by other persons satisfactory to the Company on the terms contained in this Agreement. If, within 36 hours after any such default by any Underwriter, the non-defaulting Underwriters do not arrange for the purchase of such Shares, then the Company shall be entitled to a further period of 36 hours within which to procure other persons satisfactory to the non-defaulting Underwriters to purchase such Shares on such terms. If other persons become obligated or agree to purchase the Shares of a defaulting Underwriter, either the non-defaulting Underwriters or the Company may postpone the Closing Date or the Additional Closing Date, as the case may be, for up to five full business days in order to effect any changes that in the opinion of counsel for the Company or counsel for the Underwriters may be necessary in the Registration Statement, the Pricing Disclosure Package and the Prospectus or in any other document or arrangement, and the Company agrees to promptly prepare any amendment or supplement to the Registration Statement and the Prospectus that effects any such changes. As used in this Agreement, the term “Underwriter” includes, for all purposes of this Agreement unless the context otherwise requires, any person not listed in Schedule 1 hereto that, pursuant to this Section 10, purchases Shares that a defaulting Underwriter agreed but failed to purchase.

(b) If, after giving effect to any arrangements for the purchase of the Shares of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in paragraph (a) above, the aggregate number of Shares that remain unpurchased on the Closing Date or the Additional Closing Date, as the case may be, does not exceed one-eleventh of the aggregate number of Shares to be purchased on such date, then the Company shall have the right to require each non-defaulting Underwriter to purchase the number of Shares that such Underwriter agreed to purchase hereunder on such date plus such Underwriter’s pro rata share (based on the number of Shares that such Underwriter agreed to purchase on such date) of the Shares of such defaulting Underwriter or Underwriters for which such arrangements have not been made.

(c) If, after giving effect to any arrangements for the purchase of the Shares of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in paragraph (a) above, the aggregate number of Shares that remain unpurchased on the Closing Date or the Additional Closing Date, as the case may be, exceeds one-eleventh of the aggregate amount of Shares to be purchased on such date, or if the Company shall not exercise the right described in paragraph (b) above, then this Agreement or, with respect to any Additional Closing Date, the obligation of the Underwriters to purchase Shares on the Additional Closing Date, shall terminate without liability on the part of the non-defaulting Underwriters. Any termination of this Agreement pursuant to this Section 10 shall be without liability on the part of the Company, except that the Company and the Underwriters will continue to be liable for the payment of expenses as set forth in Section 11 hereof and except that the provisions of Section 7 hereof shall not terminate and shall remain in effect.

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(d) Nothing contained herein shall relieve a defaulting Underwriter of any liability it may have to the Company or any non-defaulting Underwriter for damages caused by its default.

11. Payment of Expenses .

(a) Whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, the Company will pay or cause to be paid all costs and expenses incident to the performance of its obligations hereunder, including without limitation, (i) the costs incident to the authorization, issuance, sale, preparation and delivery of the Shares and any taxes payable in that connection; (ii) the costs incident to the preparation, printing and filing under the Securities Act of the Registration Statement, the Preliminary Prospectus, any Issuer Free Writing Prospectus, any Pricing Disclosure Package and the Prospectus (including all exhibits, amendments and supplements thereto) and the distribution thereof; (iii) the fees and expenses of the Company’s counsel and independent accountants; (iv) the reasonable fees and expenses incurred in connection with the registration or qualification and determination of eligibility for investment of the Shares under the laws of such jurisdictions as the Underwriters may designate and the preparation, printing and distribution of a Blue Sky Memorandum (including the related reasonable fees and expenses of counsel for the Underwriters); (v) the cost of preparing stock certificates; (vi) the costs and charges of any transfer agent and any registrar; (vii) all reasonable expenses and application fees incurred in connection with any filing with, and clearance of the offering by, FINRA (including the related fees and expenses of counsel for the Underwriters; provided , that such fees and expenses shall not exceed $10,000 in the aggregate); (viii) all expenses incurred by the Company in connection with any “road show” presentation to potential investors (other than as set forth in the next sentence); and (ix) all expenses and application fees related to the listing of the Shares on the Nasdaq Market. The Underwriters shall pay all of their own costs and expenses, including fees of their counsel, travel and lodging expenses of their representatives and 50% of the costs of any aircraft chartered in connection with any “road show.”

(b) If (i) this Agreement is terminated pursuant to Section 9, (ii) the Company for any reason fails to tender the Shares for delivery to the Underwriters (other than because of the Underwriters’ failure to pay for the Shares) or (iii) the Underwriters decline to purchase the Shares for any reason permitted under this Agreement, the Company agrees to reimburse the Underwriters (other than defaulting underwriters under Section 10) for all out-of-pocket costs and expenses (including the reasonable fees and expenses of their counsel) reasonably incurred by the Underwriters in connection with this Agreement and the offering contemplated hereby.

12. Persons Entitled to Benefit of Agreement . This Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and any controlling persons referred to in Section 7 hereof. Nothing in this 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 provision contained herein. No purchaser of Shares from any Underwriter shall be deemed to be a successor merely by reason of such purchase.

13. Survival . The respective indemnities, rights of contribution, representations, warranties and agreements of the Company and the Underwriters contained in this Agreement or made by or on behalf of the Company or the Underwriters pursuant to this Agreement or any certificate delivered pursuant hereto 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 investigation made by or on behalf of the Company or the Underwriters.

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14. Certain Defined Terms . For purposes of this Agreement, (a) except where otherwise expressly provided, the term “affiliate” has the meaning set forth in Rule 405 under the Securities Act; (b) 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 (c) the term “subsidiary” has the meaning set forth in Rule 405 under the Securities Act.

15. Compliance with the 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)), the Underwriters are required to obtain, verify and record information that identifies their respective clients, including the Company, which information may include the name and address of their respective clients, as well as other information that will allow the Underwriters to properly identify their respective clients.

16. Miscellaneous .

(a) Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted and confirmed by any standard form of telecommunication. Notices to the Underwriters shall be given to c/o J. P. Morgan Securities LLC, 383 Madison Avenue, New York, New York 10179 (fax: (212) 622-8358), Attention: Equity Syndicate Desk and Merrill Lynch, Pierce, Fenner & Smith Incorporated, One Bryant Park, New York, New York 10036, Attention: Syndicate Department (facsimile: (646) 855-3073), with a copy to ECM Legal (facsimile: (212) 230-8730), with a copy to Latham & Watkins LLP, 12670 High Bluff Drive, San Diego, CA 92130, Attention: Cheston J. Larson and Michael E. Sullivan. Notices to the Company shall be given to it at 5500 Flatiron Parkway, Suite 100, Boulder, Colorado 80301 (fax: (303) 245-0360); Attention: Paul Gross, with a copy to Willkie Farr & Gallagher LLP, 787 Seventh Avenue, New York, NY 10019 (fax: (212) 728-8111); Attention: Thomas Mark.

(b) Governing Law. This Agreement and any claim, controversy or dispute arising under or related to this Agreement shall be governed by and construed in accordance with the laws of the State of New York applicable to agreements made and to be performed in such state.

(c) Counterparts. This 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.

(d) Amendments or Waivers. No amendment or waiver of any provision of this 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.

(e) Headings. The headings herein 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.

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If the foregoing is in accordance with your understanding, please indicate your acceptance of this Agreement by signing in the space provided below.

[Signature Page - Underwriting Agreement]

Annex A-1

Form of Opinion of Counsel for the Company

[Attached]

Annex A-2

Form of Opinion of Intellectual Property Counsel for the Company

[Attached]

Annex B

Press release announcing the offering, issued by the Company on April 16, 2018.

Press release announcing the pricing of the offering, issued by the Company on April 16, 2018.

Term sheet containing the terms of the Securities, substantially in the form of Annex C.

Annex C

Clovis Oncology, Inc.

Pricing Term Sheet

[Attached]

Free Writing Prospectus

Filed pursuant to Rule 433

Registration Statement No. 333-215400

Dated April 16, 2018

Supplementing the

Preliminary Prospectus Supplements dated April 16, 2018

(To Prospectus dated April 16, 2018)

PRICING TERM SHEET

April 16, 2018

Clovis Oncology, Inc.

Offerings of

$300,000,000 Aggregate Principal Amount of

1.25% Convertible Senior Notes due 2025

and

1,837,898 Shares of Common Stock

The information in this pricing term sheet relates to the offering by Clovis Oncology, Inc. of its 1.25% Convertible Senior Notes due 2025 (the “Notes Offering”) and the offering by Clovis Oncology, Inc. of shares of its common stock, par value $0.001 per share (the “Common Stock Offering”), and should be read together with the preliminary prospectus supplement, dated April 16, 2018, relating to the Notes Offering (the “Notes Offering Preliminary Prospectus Supplement”), or the preliminary prospectus supplement, dated April 16, 2018, relating to the Common Stock Offering (the “Common Stock Offering Preliminary Prospectus Supplement” and, together with the Notes Offering Preliminary Prospectus Supplement, the “Prospectus Supplements”). The information in this pricing term sheet supersedes the information in the applicable Preliminary Prospectus Supplement to the extent inconsistent with the information in such Preliminary Prospectus Supplement. Terms used, but not defined, in this pricing term sheet have the respective meanings set forth in the applicable Preliminary Prospectus Supplement. As used in this pricing term sheet, “we,” “our” and “us” refer to Clovis Oncology, Inc. and not to its subsidiaries.

The Notes Offering and the Common Stock Offering are separate offerings that are being made pursuant to separate prospectus supplements. The closing of the Notes Offering is not conditioned upon the closing of the Common Stock Offering, and the closing of the Common Stock Offering is not conditioned upon the closing of the Notes Offering.

Merrill Lynch, Pierce, Fenner & Smith

                     Incorporated

Notes Offering

Merrill Lynch, Pierce, Fenner & Smith

                     Incorporated

The exact stock prices and effective dates or redemption notice dates may not be set forth in the table above, in which case:

Notwithstanding the foregoing, in no event will the conversion rate per $1,000 principal amount of Notes exceed 18.3789 shares of Common Stock, subject to adjustment in the same manner as the conversion rate as set forth in the Notes Offering Preliminary Prospectus Supplement under the caption “Description of notes—Conversion rights—Conversion rate adjustments.”

* * *

The Issuer has filed a preliminary prospectus supplement and a registration statement (including a prospectus) with the Securities and Exchange Commission (the “SEC”) for each offering to which this communication relates. Before you invest, you should read the applicable preliminary prospectus supplement and the prospectus in that registration statement and other documents the Issuer has filed with the SEC for more complete information about the Issuer and these offerings. You may get these documents for free by visiting EDGAR on the SEC website at www.sec.gov . Alternatively, any underwriter or any dealer participating in these offerings will arrange to send you the applicable preliminary prospectus supplement and the prospectus upon request to J.P. Morgan Securities LLC, Attention: c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY 11717, or (866) 803-9204; or Merrill Lynch, Pierce, Fenner & Smith Incorporated, at (800) 294-1322.

ANY DISCLAIMERS OR OTHER NOTICES THAT MAY APPEAR BELOW ARE NOT APPLICABLE TO THIS COMMUNICATION AND SHOULD BE DISREGARDED. SUCH DISCLAIMERS OR OTHER NOTICES WERE AUTOMATICALLY GENERATED AS A RESULT OF THIS COMMUNICATION BEING SENT VIA BLOOMBERG OR ANOTHER EMAIL SYSTEM.

Annex D

Foreign Qualifications

Colorado

California

Exhibit A

FORM OF LOCK-UP AGREEMENT

April 16, 2018

J.P. MORGAN SECURITIES LLC

MERRILL LYNCH, PIERCE, FENNER & SMITH

                    INCORPORATED

c/o

J.P. Morgan Securities LLC

383 Madison Avenue

New York, New York 10179

Merrill Lynch, Pierce, Fenner & Smith

                    Incorporated

One Bryant Park

New York, New York 10036

Ladies and Gentlemen:

The undersigned understands that you propose to enter into an underwriting agreement (the “ Underwriting Agreement ”) with Clovis Oncology, Inc., a Delaware corporation (the “ Company ”), providing for the public offering (the “ Public Offering ”) by us (the “ Underwriters ”) of common stock of the Company (the “ Securities ”). Capitalized terms used herein and not otherwise defined shall have the meanings set forth in the Underwriting Agreement.

In consideration of the Underwriters’ agreement to purchase and make the Public Offering of the Securities, and for other good and valuable consideration, the receipt of which is hereby acknowledged, the undersigned hereby agrees that, without the prior written consent of the Underwriters, the undersigned will not, during the period beginning on the date of this letter agreement (this “ Letter Agreement ”) and ending 60 days after the date of the final prospectus relating to the Public Offering (the “ Prospectus ” and such period, the “ Lock-Up Period ”), (1) 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, or otherwise transfer or dispose of, directly or indirectly, any shares of common stock, $0.001 per share par value, of the Company (the “ Common Stock ”) or any securities convertible into or exercisable or exchangeable for Common Stock (including, without limitation, Common Stock or such other securities which may be deemed to be beneficially owned (as a result of the power to dispose) by the undersigned in accordance with the rules and regulations of the Securities and Exchange Commission and securities which may be issued upon exercise of a stock option or warrant), or publicly disclose

the intention to make any offer, sale, pledge or disposition, (2) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Common Stock or such other securities, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise or (3) make any demand for or exercise any right with respect to the registration of any shares of Common Stock or any security convertible into or exercisable or exchangeable for Common Stock, in each case other than (A) transfers as a bona fide gift or gifts, (B) if the undersigned is a partnership, limited liability company or corporation, distributions to partners, members or stockholders of the undersigned, (C) transfers to any trust for the direct or indirect benefit of the undersigned or a member of the immediate family of the undersigned, (D) transfers to any corporation, partnership, limited liability company or other entity all of the beneficial ownership interests of which are held by the undersigned, (E) transfers by will, other testamentary document or intestate succession to the legal representative, heir, beneficiary or a member of the immediate family of the undersigned, (F) transfers to any affiliate of the undersigned or any investment fund or other entity controlled or managed by the undersigned, (G) the establishment of any contract, instruction or plan that satisfies all of the requirements of Rule 10b5-1 (a “ Rule 10b5-1 Plan ”) under the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”); provided , however , that no sales of Common Stock or securities convertible into, or exchangeable or exercisable for, Common Stock, shall be made pursuant to such Rule 10b5-1 Plan prior to the expiration of the Lock-Up Period referred to above, (H) transfers or sales of Common Stock pursuant to any contract, instruction or plan, including a Rule 10b5-1 Plan that has been entered into by the undersigned prior to the date of this Letter Agreement or any amendment or replacement of any such contract, instruction or plan, so long as the number of shares of Common Stock subject to such contract, instruction or plan is not increased or (I) transfers or sales of Common Stock to cover tax withholding obligations in connection with the vesting event of restricted stock units; provided that the remaining shares of Common Stock received upon settlement of such restricted stock units shall be subject to the restrictions on transfers set forth in this Letter Agreement; provided that, in the case of any transfer or distribution pursuant to clause (A), (B), (C), (D) or (F), each donee, transferee or distributee shall execute and deliver to the Underwriters prior to such transfer a lock-up letter in the form of this Letter Agreement; provided , further , that, in the case of any transfer or distribution pursuant to clause (A), (B), (C), (D) or (F), no filing by any party (donor, donee, transferor or transferee) under the Exchange Act, or other public announcement shall be required or shall be made voluntarily in connection with such transfer or distribution (other than after the expiration of the Lock-Up Period and other than, in the case of a transfer pursuant to clause (A), the filing of a Form 5); and provided further , that any transfer or distribution pursuant to clause (A), (B), (C), (D) or (F) shall not involve a disposition for value.

Furthermore, notwithstanding the restrictions imposed by this Letter Agreement, the undersigned may, without the prior written consent of the Underwriters, exercise an option to purchase shares of Common Stock granted under any stock incentive plan or stock purchase plan of the Company, so long as the shares issued upon such exercise are subject to the requirements of this Letter Agreement. For purposes of this Letter Agreement, “immediate family” shall mean any relationship by blood, marriage or adoption, not more remote than first cousin.

In furtherance of the foregoing, the Company, and any duly appointed transfer agent for the registration or transfer of the securities described herein, are hereby authorized to decline to make any transfer of securities if such transfer would constitute a violation or breach of this Letter Agreement.

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Letter Agreement. All authority herein conferred or agreed to be conferred and any obligations of the undersigned shall be binding upon the successors, assigns, heirs or personal representatives of the undersigned.

The undersigned understands that, if the Underwriting Agreement does not become effective by April 26, 2018, or if prior to such date the Underwriters, on the one hand, or the Company, on the other hand, informs the other(s) in writing that they have determined not to proceed with the Public Offering, or if the Underwriting Agreement (other than the provisions thereof which survive termination) shall terminate or be terminated prior to payment for and delivery of the Common Stock to be sold thereunder, the undersigned shall be released from all obligations under this Letter Agreement. The undersigned understands that the Underwriters are entering into the Underwriting Agreement and proceeding with the Public Offering in reliance upon this Letter Agreement.

This Letter Agreement and any claim, controversy or dispute arising under or related to this Letter Agreement shall be governed by and construed in accordance with the laws of the State of New York, without regard to the conflict of laws principles thereof.

Exhibit 1.2

Execution Version

CLOVIS ONCOLOGY, INC.

1.25% Convertible Senior Notes due 2025

Underwriting Agreement

April 16, 2018

J.P. MORGAN SECURITIES LLC

MERRILL LYNCH, PIERCE, FENNER & SMITH

                    INCORPORATED

c/o

J. P. Morgan Securities LLC

383 Madison Avenue

New York, New York 10179

Merrill Lynch, Pierce, Fenner & Smith

                    Incorporated

One Bryant Park

New York, New York 10036

Ladies and Gentlemen:

Clovis Oncology, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to you, the several underwriters listed in Schedule 1 hereto (the “Underwriters”), $300,000,000 principal amount of its 1.25% Convertible Senior Notes due 2025 (the “Underwritten Securities”) and, at the option of the Underwriters, up to an additional $45,000,000 principal amount of its 1.25% Convertible Senior Notes due 2025 (the “Option Securities”) if and to the extent that the Underwriters shall have determined to exercise the option to purchase such 1.25% Convertible Senior Notes due 2025 granted to the Underwriters in Section 2 hereof. The Underwritten Securities and the Option Securities are herein referred to as the “Securities”. The Securities will be convertible into shares (the “Underlying Securities”) of common stock of the Company, par value $0.001 per share (the “Common Stock”). The Securities will be issued pursuant to an Indenture to be dated as of the Closing Date (as defined below) (the “ Base Indenture”), between the Company and Bank of New York Mellon Trust Company, N.A., as trustee (the “Trustee”) as supplemented by that certain First Supplemental Indenture to such Base Indenture between the Company and the Trustee (the “First Supplemental Indenture” and together with the Base Indenture, the “Indenture”).

The Company hereby confirms its agreement with the several Underwriters concerning the purchase and sale of the Securities, as follows:

1. Registration Statement . The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Securities Act”), a registration statement on Form S-3 (File No. 333-215400), as amended by Post-Effective Amendment No. 1 thereto, including a prospectus, relating to the Securities. Such registration statement, as amended at the time it became effective, including the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Securities Act to be part of the registration statement at the time of its effectiveness (“Rule 430 Information”), is referred to herein as the “Registration Statement;” and as used herein, the term

“Preliminary Prospectus” means any prospectus filed with the Commission pursuant to Rule 424(b) under the Securities Act and the prospectus included in the Registration Statement at the time of its effectiveness that omits Rule 430 Information, and the term “Prospectus” means the prospectus in the form first used (or made available upon request of purchasers pursuant to Rule 173 under the Securities Act) in connection with confirmation of sales of the Securities. If the Company has filed an abbreviated registration statement pursuant to Rule 462(b) under the Securities Act (the “Rule 462 Registration Statement”), then any reference herein to the term “Registration Statement” shall be deemed to include such Rule 462 Registration Statement. Any reference in this underwriting agreement (this “Agreement”) to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, as of the effective date of the Registration Statement or the date of the Preliminary Prospectus or the Prospectus, as the case may be, and any reference to “amend,” “amendment” or “supplement” with respect to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed after such date under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Exchange Act”) that are deemed to be incorporated by reference therein. Capitalized terms used but not defined herein shall have the meanings given to such terms in the Registration Statement and the Prospectus.

At or prior to the Time of Sale (as defined below), the Company had prepared the following information (collectively with the pricing information set forth on Annex B, the “Time of Sale Information”): a Preliminary Prospectus dated April 16, 2018 and each “free-writing prospectus” (as defined pursuant to Rule 405 under the Securities Act) listed on Annex A hereto.

“Time of Sale” means 8:15 am, New York City time, on April 17, 2018.

2. Purchase of the Securities by the Underwriters .

(a) The Company agrees to issue and sell the Underwritten Securities to the several Underwriters as provided in this Agreement, and each Underwriter, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, agrees, severally and not jointly, to purchase from the Company the respective principal amount of Underwritten Securities set forth opposite such Underwriter’s name in Schedule 1 hereto at a price equal to 97.25% of the principal amount thereof (the “Purchase Price”) plus accrued interest, if any, from April 19, 2018 to the Closing Date (as defined below).

In addition, the Company agrees to issue and sell the Option Securities to the several Underwriters as provided in this Agreement, and the Underwriters, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, shall have the option to purchase, severally and not jointly, from the Company the Option Securities at the Purchase Price plus accrued interest, if any, from April 19, 2018 to the Additional Closing Date (as defined below).

If any Option Securities are to be purchased, the principal amount of Option Securities to be purchased by each Underwriter shall be the principal amount of Option Securities which bears the same ratio to the aggregate principal amount of Option Securities being purchased as the principal amount of Underwritten Securities set forth opposite the name of such Underwriter in Schedule 1 hereto (or such amount increased as set forth in Section 10 hereof) bears to the aggregate principal amount of Underwritten Securities being purchased from the Company by the several Underwriters, subject, however, to such adjustments to eliminate Securities in denominations other than $1,000 as the Underwriters in their sole discretion shall make.

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The Underwriters may exercise the option to purchase the Option Securities at any time in whole, or from time to time in part, on or before the thirtieth day following the date of the Prospectus, by written notice from the Underwriters to the Company. Such notice shall set forth the aggregate principal amount of Option Securities plus accrued interest as to which the option is being exercised and the date and time when the Option Securities are to be delivered and paid for, which may be the same date and time as the Closing Date (as hereinafter defined) but shall not be earlier than the Closing Date nor later than the tenth full business day after the date of such notice (unless such time and date are postponed in accordance with the provisions of Section 10 hereof). Except with respect to Option Securities to be purchased on the Closing Date, if any, any such notice shall be given at least two business days prior to the date and time of delivery specified therein.

(b) The Company understands that the Underwriters intend to make a public offering of the Securities as soon after the effectiveness of this Agreement as in the judgment of the Underwriters is advisable, and initially to offer the Securities on the terms set forth in the Time of Sale Information. The Company acknowledges and agrees that the Underwriters may offer and sell Securities to or through any affiliate of an Underwriter and that any such affiliate may offer and sell Securities purchased by it to or through any Underwriter.

(c) Payment for the Securities shall be made by wire transfer in immediately available funds to the account specified by the Company to the Underwriters in the case of the Underwritten Securities, at the offices of Latham & Watkins LLP, counsel for the Underwriters, at 12670 High Bluff Drive, San Diego, CA 92130 at 10:00 A.M., New York City time, on April 19, 2018, or at such other time or place on the same or such other date, not later than the fifth business day thereafter, as the Underwriters and the Company may agree upon in writing or, in the case of the Option Securities, on the date and at the time and place specified by the Underwriters in the written notice of the Underwriters’ election to purchase such Option Securities. The time and date of such payment for the Underwritten Securities is referred to herein as the “Closing Date,” and the time and date for such payment for the Option Securities, if other than the Closing Date, is herein referred to as the “Additional Closing Date.”

Payment for the Securities to be purchased on the Closing Date or the Additional Closing Date, as the case may be, shall be made against delivery to the nominee of the Depository Trust Company (“DTC”) for the respective accounts of the several Underwriters of the Securities to be purchased on such date of one or more global notes representing the securities (collectively, the “Global Note”), with any transfer taxes payable in connection with the sale of such Securities duly paid by the Company. The Global Note will be made available for inspection by the Underwriters at the office of J.P. Morgan Securities LLC set forth above not later than 1:00 P.M., New York City time, on the business day prior to the Closing Date or the Additional Closing Date, as the case may be.

(d) The Company acknowledges and agrees that the Underwriters are acting solely in the capacity of an arm’s length contractual counterparty to the Company with respect to the offering of Securities contemplated hereby (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, the Underwriters are not 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 the Underwriters shall have no responsibility or liability to the Company with respect thereto. Any review by the Underwriters of the Company, the transactions contemplated hereby or other matters relating to such transactions will be performed solely for the benefit of the Underwriters and shall not be on behalf of the Company.

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3. Representations and Warranties of the Company . The Company represents and warrants to each Underwriter that:

(a) Preliminary Prospectus. No order preventing or suspending the use of any Preliminary Prospectus included in the Time of Sale Information has been issued by the Commission, and the Preliminary Prospectus included in the Time of Sale Information, at the time of filing thereof, complied in all material respects with the Securities Act, and such Preliminary Prospectus, at the time of filing thereof, did not contain any 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 that the Company makes no representation or warranty with respect to any statements or omissions made in reliance upon and in conformity with information furnished to the Company in writing by such Underwriter expressly for use in such Preliminary Prospectus, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof.

(b) Time of Sale Information . The Time of Sale Information, at the Time of Sale, did not, and as of the Closing Date, as the case may be, will not, contain any 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 that the Company makes no representation or warranty with respect to any statements or omissions made in reliance upon and in conformity with information furnished to the Company in writing by such Underwriter expressly for use in such Time of Sale Information, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof. No statement of material fact included in the Prospectus has been omitted from the Time of Sale Information and no statement of material fact included in the Time of Sale Information that is required to be included in the Prospectus has been omitted therefrom.

(c) Issuer Free Writing Prospectus. Other than the Registration Statement, the Preliminary Prospectus included in the Time of Sale Information and the Prospectus, the Company (including its agents and representatives, other than the Underwriters in their capacity as such) has not made, used, prepared, authorized, approved or referred to and will not make, prepare, use, authorize, approve or refer to any “written communication” (as defined in Rule 405 under the Securities Act) that constitutes an offer to sell or solicitation of an offer to buy the Securities (each such communication by the Company or its agents and representatives (other than a communication referred to in clause (i) below) an “Issuer Free Writing Prospectus”) other than (i) any document not constituting a prospectus pursuant to Section 2(a)(10)(a) of the Securities Act or Rule 134 under the Securities Act or (ii) the documents listed on Annex A hereto, each electronic road show and any other written communications approved in writing in advance by the Underwriters. Each such Issuer Free Writing Prospectus complied in all material respects with the Securities Act, has been or will be (within the time period specified in Rule 433) filed in accordance with the Securities Act (to the extent required thereby) and, when taken together with any other Issuer Free Writing Prospectus and the Preliminary Prospectus accompanying, or delivered prior to delivery of, such Issuer Free Writing Prospectus, did not, and as of the Closing Date and as of the Additional Closing Date, as the case may be, will not, contain any 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 that the Company makes no representation or warranty with respect to any statements or omissions made in each such Issuer Free Writing Prospectus or Preliminary Prospectus in reliance upon and in conformity with information furnished to the Company in writing by such Underwriter expressly for use in such Issuer Free Writing Prospectus or

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Preliminary Prospectus, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof. Each such Issuer Free Writing Prospectus, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Securities or until any earlier date that the Company notified or notifies the Underwriters as described in Section 4(d), did not, does not and will not include any information that conflicted, conflicts or will conflict with the information contained in the Registration Statement or the Prospectus.

(d) Registration Statement and Prospectus. The Registration Statement is an “automatic shelf registration statement” as defined under Rule 405 of the Securities Act that has been filed with the Commission not earlier than three years prior to the date hereof; and no notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act has been received by the Company. No order suspending the effectiveness of the Registration Statement has been issued by the Commission, and no proceeding for that purpose or pursuant to Section 8A of the Securities Act against the Company or related to the offering of the Securities has been initiated or to the knowledge of the Company threatened by the Commission; as of the applicable effective date of the Registration Statement and any post-effective amendment thereto, the Registration Statement and any such post-effective amendment complied and will comply in all material respects with the Securities Act and the Trust Indenture Act of 1939, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Trust Indenture Act”), and did not 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 in order to make the statements therein not misleading; and as of the date of the Prospectus and any amendment or supplement thereto and as of the Closing Date and as of the Additional Closing Date, as the case may be, the Prospectus complied and will comply in all material respects with the Securities Act and will not contain any 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 that the Company makes no representation or warranty with respect to (i) that part of the Registration Statement that constitutes the Statement of Eligibility and Qualification (Form T-1) of the Trustee under the Trust Indenture Act or (ii) any statements or omissions made in reliance upon and in conformity with information furnished to the Company in writing by such Underwriter expressly for use in the Registration Statement and the Prospectus and any amendment or supplement thereto, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof.

(e) Incorporated Documents. The documents incorporated by reference in the Registration Statement, the Prospectus and the Time of Sale Information, when they were filed with the Commission (after giving effect to any amendment or supplement filed with the Commission prior to the Time of Sale), conformed in all material respects to the requirements of the Exchange Act, and none of such documents contained any untrue statement of a material fact or omitted to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; and any further documents so filed and incorporated by reference in the Registration Statement, the Prospectus or the Time of Sale Information during the Prospectus Delivery Period (as defined below), when such documents are filed with the Commission, will conform in all material respects to the requirements of the Exchange Act and will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

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(f) Financial Statements. The financial statements (including the related notes thereto) of the Company and its consolidated subsidiaries included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus comply in all material respects with the applicable requirements of the Securities Act and the Exchange Act, as applicable, and present fairly, in all material respects, the financial position of the Company and its consolidated subsidiaries as of the dates indicated and the results of their operations and the changes in their cash flows for the periods specified; such financial statements have been prepared in conformity with generally accepted accounting principles in the United States applied on a consistent basis throughout the periods covered thereby, except in the case of unaudited financial statements, which do not contain certain footnotes as permitted by the rules of the Commission, and any supporting schedules included or incorporated by reference in the Registration Statement present fairly, in all material respects, the information required to be stated therein; and the other financial information included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus has been derived from the accounting records of the Company and its consolidated subsidiaries and presents fairly, in all material respects, the information shown thereby.

(g) No Material Adverse Change. Since the date of the most recent financial statements of the Company included or incorporated by reference in the Time of Sale Information and the Prospectus, (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 and warrants described as outstanding in, and the grant of options and awards under existing equity incentive plans described in, the Registration Statement, the Time of Sale Information and the Prospectus), or long-term debt or any material change in short-term debt 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 involving 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 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, except in each case as otherwise disclosed in the Time of Sale Information and the Prospectus.

(h) Organization and Good Standing. The Company and each of its subsidiaries have been duly organized and are validly existing and in good standing (where such concept is recognized) 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, or would reasonably be expected to 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 (a “Material Adverse Effect”). The Company does not own or control, directly or indirectly, any corporation, association or other entity other than the

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subsidiaries listed in Exhibit 21.1 to the Company’s Form 10-K for the year ended December 31, 2017. None of the subsidiaries of the Company have any assets, liabilities or operations that are material to the business and operations of the Company and its subsidiaries taken as a whole.

(i) Capitalization. The Company has an authorized capitalization as set forth in the Registration Statement, the Time of Sale Information and the Prospectus under the headings “Capitalization,” “Description of Common Stock,” “Description of Other Capital Stock and Governing Documents” and “Description of Debt Securities;” 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 are not subject to any pre-emptive or similar rights; except as described in or expressly contemplated by the Time of Sale Information and the Prospectus, there are no outstanding rights (including, without limitation, pre-emptive rights), warrants or options to acquire, or instruments convertible into or exchangeable for, any shares of capital stock or other equity interest in the Company or any of its subsidiaries, or any contract, commitment, agreement, understanding or arrangement of any kind relating to the issuance of any capital stock of the Company or any such subsidiary, any such convertible or exchangeable securities or any such rights, warrants or options; the capital stock of the Company conforms in all material respects to the description thereof contained in the Registration Statement, the Time of Sale Information and the 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.

(j) Stock Options. 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 Plans”), (i) each Stock Option intended to qualify as an “incentive stock option” under Section 422 of the Code so qualified as of the applicable Grant Date (as defined below), (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, and (iv) each such grant was properly accounted for in accordance with accounting principles generally accepted in the United States in the financial statements (including the related notes) of the Company. Each Company Stock Plan is accurately described in all material respects in the Registration Statement, the Time of Sale Information and the Prospectus.

(k) Due Authorization. The Company has full right, power and authority to execute and deliver this Agreement, the Indenture and the Securities (collectively, the “Transaction Documents”) and to perform its obligations hereunder and thereunder; and all action required to be taken for the due and proper authorization, execution and delivery by it of each of the Transaction Documents and the consummation by it of the transactions contemplated thereby has been duly and validly taken.

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(l) The Indenture . The Indenture has been duly authorized by the Company and on the Closing Date and on the Additional Closing Date, as the case may be, will have been duly executed and delivered in accordance with its terms by the Company and, assuming the due authorization, execution and delivery by the Trustee, will constitute a valid and legally binding agreement of the Company enforceable against the Company in accordance with its terms, except as enforceability may be limited by applicable bankruptcy, insolvency or similar laws affecting the enforcement of creditors’ rights generally or by equitable principles relating to enforceability (collectively, the “Enforceability Exceptions”) and the Indenture will conform in all material respects to the requirements of the Trust Indenture Act.

(m) Underwriting Agreement. This Agreement has been duly authorized, executed and delivered by the Company.

(n) The Securities. The Securities to be issued and sold hereunder have been duly authorized by the Company and, when duly executed, authenticated, issued and delivered as provided in the Indenture and paid for as provided herein, will be duly and validly issued and outstanding and will constitute valid and legally binding obligations of the Company enforceable against the Company in accordance with their terms, subject to the Enforceability Exceptions, and will be entitled to the benefits of the Indenture.

(o) The Underlying Securities . Upon issuance and delivery of the Securities in accordance with this Agreement and the Indenture, the Securities will be convertible at the option of the holder thereof into shares of the Underlying Securities in accordance the terms of the Securities and the Indenture; the Underlying Securities reserved for issuance upon conversion of the Securities have been duly authorized and reserved and, when issued upon conversion of the Securities in accordance with the terms of the Securities and the Indenture, will be validly issued, fully paid and non assessable, and the issuance of the Underlying Securities will not be subject to any preemptive or similar rights.

(p) Descriptions of the Transaction Documents. Each Transaction Document conforms in all material respects to the description thereof contained in the Time of Sale Information and the Prospectus.

(q) No Violation or Default. Neither the Company nor any of its subsidiaries is (i) in violation of its charter or by-laws or similar organizational documents; (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.

(r) No Conflicts. The execution, delivery and performance by the Company of each of the Transaction Documents, the issuance and sale of the Securities (including the issuance of the Underlying Securities upon conversion thereof) and the consummation by the Company of the transactions contemplated by the Transaction Documents 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, right or asset of the Company or any of its

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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, right 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 similar 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 applicable to the Company, except, in the case of clauses (i) and (iii) above, for any such conflict, breach, violation, default, termination, modification, acceleration, lien, charge or encumbrance that would not, individually or in the aggregate, have a Material Adverse Effect.

(s) No Consents Required. No consent, filing, approval, authorization, order, 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 each of the Transaction Documents, the issuance and sale of the Securities (including the issuance of the Underlying Securities upon conversion thereof) and the consummation by the Company of the transactions contemplated by the Transaction Documents, except for the registration of the Securities under the Securities Act, the qualification of the Indenture under the Trust Indenture Act and such filings, consents, approvals, authorizations, orders and registrations or qualifications (i) which have been obtained or made or (ii) as may be required by the Nasdaq Market and under applicable state securities laws in connection with the purchase and distribution of the Securities by the Underwriters.

(t) No Integration . Neither the Company nor any of its affiliates has, prior to the date hereof, made any offer or sale of any securities that would be integrated with the offer and sale of the Securities contemplated by this Agreement pursuant to the Securities Act or the interpretations thereof by the Commission.

(u) Legal Proceedings. Except as described in the Registration Statement, the Time of Sale Information 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 a party or to which any property of the Company or any of its subsidiaries is subject that, individually or in the aggregate, if determined adversely to the Company or any of its subsidiaries, would reasonably be expected to have a Material Adverse Effect; to the knowledge of the Company, no such Actions are threatened or contemplated by any governmental or regulatory authority or threatened by others that do not arise out of the same underlying facts and allegations contained in the Actions disclosed in the Time of Sale Information and the Prospectus; and (i) there are no current or pending Actions that are required under the Securities Act to be described in the Registration Statement, the Time of Sale Information or the Prospectus that are not so described in the Registration Statement, the Time of Sale Information and the Prospectus and (ii) there are no statutes, regulations or contracts or other documents that are required under the Securities Act to be filed as exhibits to the Registration Statement (in the case of contracts or other documents) or described in the Registration Statement, the Time of Sale Information or the Prospectus that are not so filed as exhibits to the Registration Statement (in the case of contracts or other documents) or described in the Registration Statement, the Time of Sale Information and the Prospectus.

(v) Independent Accountants . Ernst & Young LLP, who have audited certain consolidated financial statements of the Company and its subsidiaries, 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 (United States) and as required by the Securities Act.

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(w) Title to Real and Personal Property . The Company and its subsidiaries have good and marketable title in fee simple (in the case of real property, if any) to, or have valid rights to lease or otherwise use, all items of real and tangible personal property and assets 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.

(x) Title to Intellectual Property. The Company and its subsidiaries own, or have obtained valid and enforceable licenses for, or other rights to use, the inventions, patent applications, patents, trademarks (both registered and unregistered), trade names, copyrights, trade secrets and other proprietary information (collectively, the “Intellectual Property”) described in the Registration Statement, the Time of Sale Information and the Prospectus as being owned or licensed by them, used in, or necessary for the conduct of, their respective businesses as described in the Registration Statement, the Time of Sale Information and the Prospectus, except as would not reasonably be expected to have a Material Adverse Effect; and (i) to the Company’s knowledge, there is no infringement, misappropriation or violation by third parties of any such Intellectual Property that would have a Material Adverse Effect; (ii) to the Company’s knowledge, there is no pending or threatened action, suit, proceeding or claim by others that the Company or its subsidiaries infringe, misappropriate or otherwise violate any Intellectual Property rights of others, the Company has not received any written notice of such claim, and the Company is unaware of any facts which would form a reasonable basis for a successful claim of such infringement, misappropriation or violation, in each case that would have a Material Adverse Effect; (iii) there is no pending or, to the Company’s knowledge, threatened action, suit, proceeding or claim by others challenging the rights of the Company or its subsidiaries in or to any such Intellectual Property, and the Company is unaware of any facts which it believes would form a reasonable basis for a successful challenge to the rights in such Intellectual Property, in each case that would have a Material Adverse Effect; (iv) the Intellectual Property owned by the Company and its subsidiaries and, to the Company’s knowledge, the Intellectual Property licensed to the Company and its subsidiaries have not been adjudged invalid or unenforceable, in whole or in part, and there is no pending or, to the Company’s knowledge, threatened action, suit, proceeding or claim by others challenging the validity or scope of any such Intellectual Property, and the Company is unaware of any facts which it believes would form a reasonable basis for a successful challenge to the validity, enforceability or scope of such Intellectual Property, in each case that would have a Material Adverse Effect; (v) none of the technology employed by the Company has been obtained or is being used by the Company in material violation of any contractual obligation binding on the Company or, to the Company’s knowledge, upon any of its officers, directors or employees or otherwise in violation of the rights of any persons; (vi) to the Company’s knowledge, there are no third parties who have or will be able to establish rights to any Intellectual Property described in the Registration Statement, the Time of Sale Information and the Prospectus as owned or exclusively licensed by the Company or its subsidiaries that would have a Material Adverse Effect except for licenses granted in writing by the Company or its subsidiaries to any third parties; (vii) the Company is not a party to or bound by any options, licenses or other agreements, with respect to the Company’s or a third party’s Intellectual Property, that are required to be set forth in the Registration Statement, the Time of Sale Information and the Prospectus, and that are not described in all material respects therein; (viii) to the Company’s knowledge, there is no patent or patent application that contains claims that interfere (as such term is described in 35 U.S.C. §135 and 37 C.F.R. 41.100 to 41.208) with the issued or pending claims of any of the Intellectual

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Property that would a Material Adverse Effect on the Company; and (ix) to the Company’s knowledge, there is no prior art material to any patent or patent application owned or exclusively licensed by the Company that has not been disclosed to the U.S. Patent and Trademark Office that would have a Material Adverse Effect.

(y) Healthcare Compliance . Except as described in the Registration Statement, the Time of Sale Information and the Prospectus, the Company: (i) is and at all times during the past three years has been in material compliance with all applicable laws, rules or regulations, including, without limitation, the federal Anti-Kickback Statute (42 U.S.C. § 1320a-7b(b)), the Civil Monetary Penalties Laws (42 U.S.C. § 1320a-7a), the civil False Claims Act (31 U.S.C. §§ 3729 et seq.), the administrative False Claims Law (42 U.S.C. § 1320a-7b(a)), the Physician Payments Sunshine Act (42 U.S.C. § 1320-7h), all criminal laws relating to health care fraud and abuse, including, but not limited to, 18 U.S.C. §§ 286 and 287, the Health Insurance Portability and Accountability Act of 1996 (42 U.S.C. § 1320d et seq.), 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 Federal Food, Drug and Cosmetic Act (21 U.S.C. §§ 301 et seq.) (the “FFDCA”), Medicare (Title XVIII of the Social Security Act), Medicaid (Title XIX of the Social Security Act), the collection and reporting requirements, and the processing of any applicable rebate, chargeback or adjustment, under applicable rules and regulations relating to the Medicaid Drug Rebate Program (42 U.S.C. § 1396r-8) and any state supplemental rebate program, Medicare average sales price reporting (42 U.S.C. § 1395w-3a), the Public Health Service Act (42 U.S.C. § 256b), the VA Federal Supply Schedule (38 U.S.C. § 8126) or under any state pharmaceutical assistance program or U.S. Department of Veterans Affairs agreement, and any successor government programs, each as amended, the regulations promulgated pursuant to such laws, any other similar local, state or federal law, and all applicable laws, rules or regulations of the U.S. Food and Drug Administration (“FDA”) and other comparable regulatory authorities (“Governmental Authority”) relating to the ownership, testing, development, manufacture, packaging, use, distribution, marketing, labeling, storage, import, export or disposal of any product under clinical development or manufactured by or on behalf of the Company (collectively, the “Applicable Laws”); (ii) has not received any FDA Form 483, notice of adverse finding, warning letter, untitled letter or other correspondence or notice from the FDA or any Governmental Authority alleging or asserting material noncompliance with any Applicable Laws or any licenses, certificates, approvals, clearances, exemptions, authorizations, permits and supplements or amendments thereto required by any such Applicable Laws (“Authorizations”); (iii) possesses all required material Authorizations and such Authorizations are valid and in full force and effect and the Company is not in material violation of any term of any such Authorizations; (iv) has not received notice of any claim, action, suit, proceeding, hearing, enforcement, investigation, arbitration or other action from the FDA or any Governmental Authority or third party alleging that any product, operation or activity is in material violation of any Applicable Laws or Authorizations; (v) has not received notice that the FDA or any Governmental Authority has taken, is taking or intends to take action to limit, suspend, modify or revoke any material Authorizations; (vi) has filed, obtained, maintained or submitted all material reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments as required by any Applicable Laws or Authorizations and that all such reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments were materially complete and correct on the date filed (or were corrected or supplemented by a subsequent submission); and (vii) is not a party to or has any ongoing reporting obligations pursuant to any corporate integrity agreement, deferred prosecution agreement, monitoring agreement, consent decree, settlement order, plan of correction or similar agreement imposed by any governmental authority. To the knowledge of the Company, all third

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parties that are collaborating with the Company with respect to the clinical development or manufacture of companion diagnostics are in material compliance with all Applicable Laws and possess all required material Authorizations relating to such companion diagnostics being developed in collaboration with the Company. Additionally, neither the Company, nor any of its officers or directors, nor, to the Company’s knowledge, any of its employees, has been excluded, suspended or debarred from participation in any U.S. state or federal healthcare program or human clinical research or, except as described in the Registration Statement, the Time of Sale Information and the Prospectus, is subject to a governmental inquiry, investigation, proceeding, or other any other similar action that could reasonably be expected to result in debarment, suspension, or exclusion of such person.

(z) Clinical Studies . The studies, tests and preclinical and clinical trials conducted by or, to the Company’s knowledge, on behalf of the Company or by third parties, were and, if still ongoing, are being conducted in all material respects in accordance with experimental protocols, procedures and controls pursuant to all Authorizations and Applicable Laws, including, without limitation, the FFDCA; the descriptions of the results of such studies, tests and trials contained in the Registration Statement, the Time of Sale Information and the Prospectus are, to the Company’s knowledge, accurate and complete in all material respects and fairly present in all material respects the data derived from such studies, tests and trials; except to the extent disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, the Company is not aware of any studies, tests or trials, the results of which the Company believes would have an adverse effect on the development of the Company’s product candidates in the Registration Statement, the Time of Sale Information and the Prospectus; and, except to the extent disclosed in the Registration Statement, the Time of Sale Information or the Prospectus, the Company has not received any written notices or correspondence from the FDA or any Governmental Authority requiring the termination or suspension of any studies, tests or preclinical or clinical trials conducted by or on behalf of the Company.

(aa) No Undisclosed Relationships . 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 Securities Act to be described in the Registration Statement and the Prospectus and that is not so described in the Registration Statement, the Prospectus and the Time of Sale Information.

(bb) Investment Company Act . The Company is not and, after giving effect to the offering and sale of the Securities and the application of the proceeds thereof as described in the Time of Sale Information and the Prospectus, will not be required to register as an “investment company” or an entity “controlled” by 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”).

(cc) Taxes. The Company and its subsidiaries have paid all federal, state, local and foreign taxes required to be paid and filed all tax returns required to be filed through the date hereof; and except as otherwise disclosed in the Registration Statement, the Time of Sale Information and the 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, except where failure to pay or file, or where such deficiency, would in any case not, individually or in the aggregate, have a Material Adverse Effect.

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(dd) Licenses and Permits. The Company and its subsidiaries possess all licenses, sub-licenses, certificates, permits and other authorizations issued by, and have made all declarations and filings with, the appropriate federal, state, local or foreign governmental or regulatory authorities that are necessary for the ownership or lease of their respective properties or the conduct of their respective businesses as described in the Registration Statement, the Time of Sale Information and the Prospectus (collectively, “Licenses”), except where the failure to possess or make the same would not, individually or in the aggregate, have a Material Adverse Effect; and except as described in the Registration Statement, the Time of Sale Information and the Prospectus, neither the Company nor any of its subsidiaries has received notice of any revocation or modification of any such License or has any reason to believe that any such License will not be renewed in the ordinary course. To the Company’s knowledge, no party granting any such Licenses has taken any action to limit, suspend or revoke the same in any material respect.

(ee) No Labor Disputes. 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 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.

(ff) Compliance With Environmental Laws. (i) The Company and its subsidiaries (a) are, and at all times during the past three years were, in compliance with any and all applicable federal, state, local and foreign laws, rules, regulations, requirements, decisions, judgments, decrees and orders relating to pollution or the protection of the environment, natural resources or human health or safety, including those relating to the generation, storage, treatment, use, handling, transportation, Release or threat of Release of Hazardous Materials (collectively, “Environmental Laws”), (b) have received and are in compliance with all permits, licenses, certificates or other authorizations or approvals required of them under applicable Environmental Laws to conduct their respective businesses, (c) have not received notice of any actual or potential liability under or relating to, or actual or potential violation of, any Environmental Laws, including for the investigation or remediation of any Release or threat of Release of Hazardous Materials, and have no knowledge of any event or condition that would reasonably be expected to result in any such notice, (d) are not conducting or paying for, in whole or in part, any investigation, remediation or other corrective action pursuant to any Environmental Law at any location, and (e) are not a party to any order, decree or agreement that imposes any obligation or liability under any Environmental Law, 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 Time of Sale Information and the Prospectus, (a) there are no proceedings that are pending, or that are known by the Company to be 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 proceedings regarding which it is reasonably believed no monetary sanctions of $100,000 or more will be imposed, (b) the Company and its subsidiaries are not aware of any facts or issues regarding the Company’s or its subsidiaries’ compliance with Environmental Laws, or liabilities or other obligations under Environmental Laws, including the Release or threat of Release of Hazardous Materials, that would reasonably be expected to have a material effect on the capital expenditures, earnings or competitive position of the Company and its subsidiaries, and (c) none of the Company and its subsidiaries anticipates material capital expenditures relating to any Environmental Laws.

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(gg) Hazardous Materials . There has been no storage, generation, transportation, use, handling, treatment, Release or threat of Release of Hazardous Materials by, relating to or caused by the Company or any of its subsidiaries (or, to the knowledge of the Company and its subsidiaries, any other entity (including any predecessor) for whose acts or omissions the Company or any of its subsidiaries is or would reasonably be expected to be liable) at, on, under or from any property or facility now or previously owned, operated or leased by the Company or any of its subsidiaries, or at, on, under or from any other property or facility, in violation of any Environmental Laws or in a manner or amount or to a location that would reasonably be expected to result in any liability under any Environmental Law, except for any violation or liability which would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. “Hazardous Materials” means any material, chemical, substance, waste, pollutant, contaminant, compound, mixture, or constituent thereof, in any form or amount, including petroleum (including crude oil or any fraction thereof) and petroleum products, natural gas liquids, asbestos and asbestos containing materials, naturally occurring radioactive materials, brine, and drilling mud, regulated by a governmental agency or which can give rise to liability under any Environmental Law. “Release” means any spilling, leaking, seepage, pumping, pouring, emitting, emptying, discharging, injecting, escaping, leaching, dumping, disposing, depositing, dispersing, or migrating in, into or through the environment, or in, into from or through any building or structure.

(hh) Compliance with ERISA. Except as would not reasonably be expected to have a Material Adverse Effect: (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 of its subsidiaries has 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 Internal Revenue Code of 1986, as amended (the “Code”); (ii) to the Company’s knowledge, 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, the minimum funding standard of Section 412 of the Code or Section 302 of ERISA, as applicable, has been satisfied (without taking into account any waiver thereof or extension of any amortization period) and is reasonably expected to be satisfied in the future (without taking into account any waiver thereof or extension of any amortization period); (iv) no “reportable event” (within the meaning of Section 4043(c) of ERISA) has occurred or is reasonably expected to occur that either has resulted, or would reasonably be expected to result, in liability to the Company or its subsidiaries; (v) neither the Company nor any member of the “Controlled Group” (defined as any organization which is a member of a controlled group of corporations within the meaning of Section 414 of the Code) 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 Guaranty Corporation (the “PBGC”)) in respect of a Plan; and (vi) to the knowledge of the Company, there is no pending audit or investigation by the Internal Revenue Service, the U.S. Department of Labor, the PBGC or any other governmental agency or any foreign regulatory agency with respect to any Plan. None of the following events has occurred: (x) a material increase in the aggregate amount of contributions required to be made to all Plans subject to Title IV of ERISA by the Company or its subsidiaries in the current fiscal year of the Company and its subsidiaries compared to the amount of such contributions made in the Company and its subsidiaries’ most recently completed fiscal year; or (y) a material increase in the Company and its subsidiaries’ “accumulated post-retirement benefit obligations” (within the meaning of Statement of Financial Accounting Standards 106) compared to the amount of such obligations in the Company and its subsidiaries’ most recently completed fiscal year.

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(ii) Disclosure Controls . The Company and its subsidiaries maintain a 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 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.

(jj) Accounting Controls. 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 U.S. generally accepted accounting principles. The Company and its subsidiaries maintain a system of 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 U.S. generally accepted accounting principles and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; (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 and (v) interactive data in eXtensible Business Reporting Language incorporated by reference in the Registration Statement, the Prospectus and the Time of Sale Information fairly presents the information called for in all material respects and is prepared in accordance with the Commission’s rules and guidelines applicable thereto. Except as disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, there are no material weaknesses in the Company’s internal controls over financial reporting. The Company’s auditors and the Audit Committee of the Board of Directors of the Company have been advised of: (i) any 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) 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.

(kk) eXtensible Business Reporting Language. The interactive data in eXtensible Business Reporting Language incorporated by reference in the Registration Statement 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.

(ll) Insurance. The Company and its subsidiaries have insurance covering their respective properties, operations, personnel and businesses, which insurance is in amounts and insures against such losses and risks as 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

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other expenditures are required or necessary to be made in order to continue such insurance or (ii) any reason to believe that it will not be able 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.

(mm) No Unlawful Payments. Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee, affiliate or other person associated with or acting on behalf of the Company or any of its subsidiaries has (i) used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity; (ii) 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) 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 committed an offence under the Bribery Act 2010 of the United Kingdom or any other applicable anti-bribery or anti-corruption law; or (iv) 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, in each case, prohibited by applicable law. The Company and its subsidiaries have instituted, maintain and enforce policies and procedures designed to promote and ensure compliance with all applicable anti-bribery and anti-corruption laws.

(nn) Compliance with Anti-Money Laundering Laws . The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements, 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 issued, administered or enforced by any governmental or regulatory agency (collectively, the “Anti-Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental or regulatory 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.

(oo) No Conflicts with Sanctions Laws. Neither the Company nor any of its subsidiaries, directors or officers, nor, to the knowledge of the Company, any employees, agents, affiliates or other person associated with or acting on behalf of the Company or any of its subsidiaries is 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 is the Company or any of its subsidiaries located, organized or resident in a country or territory that is the subject or target of comprehensive (rather than list-based) Sanctions, including, without limitation, Cuba, Iran, North Korea, Sudan, Syria and Crimea (each, a “Sanctioned Country”); and the Company will not directly or indirectly use the proceeds of the offering of the Securities hereunder, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or

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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 (5) years, (i) the Company and its subsidiaries (other than Clovis Italy and its subsidiaries) have not knowingly engaged in and are not now knowingly engaged in any transactions with any person that at the time of the transaction is or was the subject of Sanctions, (ii) Clovis Italy and its subsidiaries since the date of their acquisition by the Company 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 transaction is or was the subject or the target of Sanctions or with any Sanctioned Country and (iii) prior to the date of their acquisition by the Company, to the knowledge of the Company, neither Clovis Italy nor its subsidiaries knowingly engaged in any 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.

(pp) No Restrictions on Subsidiaries . Subject to any restrictions under applicable law, 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.

(qq) No Broker’s Fees. Neither the Company nor any of its subsidiaries is a party to any contract, agreement or understanding with any person (other than this Agreement) that would give rise to a valid claim against the Company or any of its subsidiaries or any Underwriter for a brokerage commission, finder’s fee or like payment in connection with the offering and sale of the Securities.

(rr) No Registration Rights . Except as described in or expressly contemplated by the Registration Statement, the Time of Sale Information and the Prospectus, no person has the right to require the Company or any of its subsidiaries to register any securities for sale under the Securities Act by reason of the filing of the Registration Statement with the Commission or the issuance and sale of the Securities by the Company, which such right has not been waived.

(ss) No Stabilization. The Company has not taken, directly or indirectly, any action designed to or that would reasonably be expected to cause or result in any stabilization or manipulation of the price of the Securities.

(tt) Margin Rules . The application of the proceeds received by the Company from the issuance, sale and delivery of the Securities as described in the Registration Statement, the Time of Sale Information and the 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.

(uu) Forward-Looking Statements . No forward looking statement (within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act) included or incorporated by reference in any of the Registration Statement, the Time of Sale Information or the Prospectus has been made or reaffirmed without a reasonable basis or has been disclosed other than in good faith.

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(vv) Statistical and Market Data. Nothing has come to the attention of the Company that has caused the Company to believe that the statistical and market-related data included or incorporated by reference in each of the Registration Statement, the Time of Sale Information and the Prospectus is not based on or derived from sources that are reliable and accurate in all material respects.

(ww) Sarbanes-Oxley Act . 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 applicable provision of the Sarbanes-Oxley Act of 2002, as amended, 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.

(xx) Status under the Securities Act . At the time of filing the Registration Statement and any post-effective amendment thereto, at the earliest time thereafter that the Company or any offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) under the Securities Act) of the Securities and at the date hereof, the Company was not and is not an “ineligible issuer,” and was and is a “well-known seasoned issuer,” in each case as defined in Rule 405 under the Securities Act.

(yy) Accurate Disclosure . The statements included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus, as applicable, under the headings “Risk Factors – Reimbursement may be limited or unavailable in certain market segments for our product candidates, which could make it difficult for us to sell our products profitably,” “Risk Factors – The patent protection and patent prosecution for some of our product candidates is dependent on third parties,” “Business – License Agreements,” “Business – Government Regulation,” “Business – Patents and Proprietary Rights,” “Description of Capital Stock,” “Material U.S. Federal Income and Estate Tax Considerations” and “Underwriting” insofar as such statements summarize legal matters, agreements, documents or proceedings discussed therein, are accurate and fair summaries in all material respects of such legal matters, agreements, documents or proceedings and present the information required to be shown.

(zz) No Ratings. There are (and prior to the Closing Date, will be) no debt securities or preferred stock issued or guaranteed by the Company or any of its subsidiaries that are rated by a “nationally recognized statistical rating organization,” as such term is defined in Section 3(a)(62) in the Exchange Act.

4. Further Agreements of the Company . The Company covenants and agrees with each Underwriter that:

(a) Required Filings. The Company will file the Prospectus with the Commission within the time periods specified by Rule 424(b) and Rule 430A, 430B or 430C under the Securities Act, will file any Issuer Free Writing Prospectus (including the term sheet substantially in the form of Annex B hereto) to the extent required by Rule 433 under the Securities Act; will file within the applicable time period required by the Exchange Act all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus and for so long as the delivery of a prospectus is required in connection with the offering or sale of the Securities; and the Company will furnish copies of the Prospectus and each Issuer Free Writing Prospectus (to the extent not previously delivered) to the Underwriters in New York City prior to 10:00 A.M., New York City time, as soon as practicable but in no event

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later than the second business day next succeeding the date of this Agreement, in such quantities as the Underwriters may reasonably request. The Company will pay the registration fee for this offering of the Securities within the time period required by Rule 456(b)(1) under the Securities Act (without giving effect to the proviso therein) and in any event prior to the Closing Date.

(b) Delivery of Copies. The Company will deliver to the Underwriters, without charge, (i) two signed copies of the Registration Statement as originally filed and each amendment thereto, in each case including all exhibits and consents filed therewith and (ii) during the Prospectus Delivery Period (as defined below), as many copies of the Prospectus (including all amendments and supplements thereto and documents incorporated by reference therein and each Issuer Free Writing Prospectus) as the Underwriters may reasonably request. As used herein, the term “Prospectus Delivery Period” means such period of time after the first date of the public offering of the Securities as in the opinion of counsel for the Underwriters a prospectus relating to the Securities is required by law to be delivered (or required to be delivered but for Rule 172 under the Securities Act) in connection with sales of the Securities by any Underwriter or dealer.

(c) Amendments or Supplements, Issuer Free Writing Prospectus and Exchange Act Documents. During the Prospectus Delivery Period, before using, authorizing, approving, referring to or filing any Issuer Free Writing Prospectus, and before filing any amendment or supplement to the Registration Statement or the Prospectus, the Company will furnish to the Underwriters and counsel for the Underwriters a copy of the proposed Issuer Free Writing Prospectus, amendment or supplement for review and will not use, authorize, approve, refer to or file any such Issuer Free Writing Prospectus or file any such proposed amendment or supplement to which the Underwriters reasonably object. The Company will furnish to the Underwriters and counsel for the Underwriters notice of its intention to make any filings pursuant to the Exchange Act or the Exchange Act Regulations from the Time of Sale to the Closing Date and will furnish to the Underwriters and counsel for the Underwriters a copy of any such document a reasonable amount of time prior to such proposed filing and work in good faith with the Underwriters and counsel for the Underwriters to determine the requirement, form and content of any such document and accept all reasonable comments thereto from the Underwriters.

(d) Notice to the Underwriters. During the Prospectus Delivery Period, the Company will advise the Underwriters promptly, and confirm such advice in writing (which advice may be delivered via electronic mail), (i) when any amendment to the Registration Statement has been filed or becomes effective; (ii) when any supplement to the Prospectus or any Issuer Free Writing Prospectus or any amendment to the Prospectus has been filed or distributed; (iii) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus or the receipt of any comments from the Commission relating to the Registration Statement or any other request by the Commission for any additional information; (iv) of the issuance by the Commission of any order suspending the effectiveness of the Registration Statement or preventing or suspending the use of any Preliminary Prospectus included in the Time of Sale Information, any of the Time of Sale Information or the Prospectus or the initiation or, to the Company’s knowledge, threatening of any proceeding for that purpose or pursuant to Section 8A of the Securities Act; (v) of the occurrence of any event within the Prospectus Delivery Period as a result of which the Prospectus, the Time of Sale Information or any Issuer Free Writing Prospectus as then amended or supplemented would contain any 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 existing when the Prospectus, the Time of Sale Information or any such Issuer Free Writing Prospectus is delivered to a purchaser, not misleading; (vi) of the receipt by the Company of any notice of

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objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act; and (vii) of the receipt by the Company of any notice with respect to any suspension of the qualification of the Securities for offer and sale in any jurisdiction or the initiation or, to the Company’s knowledge, threatening of any proceeding for such purpose; and the Company will use its reasonable best efforts to prevent the issuance of any such order suspending the effectiveness of the Registration Statement, preventing or suspending the use of any Preliminary Prospectus, any of the Time of Sale Information or the Prospectus or suspending any such qualification of the Securities and, if any such order is issued, will use its reasonable best efforts to obtain as soon as possible the withdrawal thereof.

(e) Ongoing Compliance. (1) If during the Prospectus Delivery Period (i) any event or development shall occur or condition shall exist as a result of which the Prospectus as then amended or supplemented would contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Prospectus to comply with law, the Company will promptly notify the Underwriters thereof and promptly prepare and, subject to paragraph (c) above, file with the Commission and furnish to the Underwriters and to such dealers as the Underwriters may designate such amendments or supplements to the Prospectus as may be necessary so that the statements in the Prospectus as so amended or supplemented will not, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, be misleading or so that the Prospectus will comply with law and (2) if at any time prior to the Closing Date (i) any event or development shall occur or condition shall exist as a result of which the Time of Sale Information as then amended or supplemented would contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances existing when the Time of Sale Information is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Time of Sale Information to comply with law, the Company will promptly notify the Underwriters thereof and promptly prepare and, subject to paragraph (c) above, file with the Commission (to the extent required) and furnish to the Underwriters and to such dealers as the Underwriters may designate such amendments or supplements to the Time of Sale Information as may be necessary so that the statements in the Time of Sale Information as so amended or supplemented will not, in the light of the circumstances existing when the Time of Sale Information is delivered to a purchaser, be misleading or so that the Time of Sale Information will comply with law.

(f) Blue Sky Compliance. The Company will qualify the Securities for offer and sale under the securities or Blue Sky laws of such jurisdictions as the Underwriters shall reasonably request and will continue such qualifications in effect so long as required for distribution of the Securities; provided that the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file any general consent to service of process in any such jurisdiction or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

(g) Earning Statement. The Company will make generally available to its security holders and the Underwriters as soon as practicable an earnings statement that satisfies the provisions of Section 11(a) of the Securities Act and Rule 158 of the Commission promulgated thereunder covering a period of at least twelve months beginning with the first fiscal quarter of the Company occurring after the “effective date” (as defined in Rule 158) of the Registration Statement, provided, however, that (1) such requirements to the Company’s security holders shall be deemed met by the Company’s compliance with its reporting requirements pursuant to the

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Exchange Act if such compliance satisfies the conditions of Rule 158 and (2) such requirements to the Underwriters shall be deemed met by the Company if the related reports are available on the Commission’s Electronic Data Gathering, Analysis and Retrieval System or any successor system.

(h) Clear Market. For a period of 60 days after the date of the Prospectus, the Company will not (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, or otherwise transfer or dispose of, directly or indirectly, or file with the Commission a registration statement under the Securities Act relating to, any shares of Stock or any securities convertible into or exercisable or exchangeable for Stock, or publicly disclose the intention to make any offer, sale, pledge, disposition or filing, or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Stock or any such other securities, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Stock or such other securities, in cash or otherwise, without the prior written consent of J.P. Morgan Securities LLC, other than (A) the Securities to be sold hereunder or the issuance of the Underlying Securities upon conversion of the Securities, (B) the shares of Common Stock to be sold pursuant to that certain Underwriting Agreement, dated as of the date hereof, by and among the Company and the Underwriters, (C) options to purchase Common Stock or other equity awards granted under the Company Stock Plans, provided that such options to purchase Common Stock or other equity awards (other than with respect to annual grants to directors) do not vest during the 60-day restricted period and do not exceed 5% of the outstanding shares of Common Stock following the consummation of the offering of the Securities, or any shares of Stock of the Company issued upon the exercise of options or other equity awards granted under Company Stock Plans, (D) the filing by the Company of any registration statement on Form S-8 or a successor form thereto relating to any shares of Common Stock granted under any Company Stock Plan, (E) the issuance of securities in connection with the acquisition by the Company of the securities, business, property or other assets (other than the in-license of a single product candidate, which shall be subject to clause (F) below) of another person or entity, or pursuant to any employee benefit plans assumed by the Company in connection with any such acquisition or (F) the issuance of securities in connection with joint ventures, commercial relationships or other strategic transactions, provided that in the case of (F), prior to any issuance the Company shall cause each recipient of such securities to execute and deliver to the Underwriters a Lock-up Agreement substantially in the form of Exhibit A and provided further that any issuances pursuant to clauses (E) and (F) above shall not, in the aggregate, exceed 5% of the outstanding shares of Common Stock on the date hereof.

(i) Use of Proceeds. The Company will apply the net proceeds from the sale of the Securities as described in the Time of Sale Information and the Prospectus under the heading “Use of Proceeds.”

(j) No Stabilization. The Company will not take, directly or indirectly, any action designed to or that would reasonably be expected to cause or result in any stabilization or manipulation of the price of the Securities.

(k) Underlying Securities . The Company will reserve and keep available at all times, free of pre-emptive rights, shares of Common Stock for the purpose of enabling the Company to satisfy all obligations to issue the Underlying Securities upon conversion of the Securities. The Company will use its reasonable best efforts to cause the Underlying Securities to be listed on the Nasdaq Global Select Market (the “Exchange”).

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(l) Reports. During the period commencing on the Closing Date and ending on the earlier of (1) when the Securities cease to be outstanding or (2) the third anniversary of the Closing Date, the Company will furnish to the Underwriters, as soon as they are available, copies of all reports or other communications (financial or other) furnished by the Company to holders of the Securities, and copies of any reports and financial statements furnished to or filed by the Company with the Commission or any national securities exchange or automatic quotation system; provided the Company will be deemed to have furnished such reports and financial statements to the Underwriters to the extent they are filed on the Commission’s Electronic Data Gathering, Analysis, and Retrieval system or any successor system.

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

(n) DTC . The Company will assist the Underwriters in arranging for the Securities to be eligible for clearance and settlement through DTC.

5. Certain Agreements of the Underwriters . Each Underwriter hereby represents to the Company and agrees with the Company that:

(a) It has not used, authorized use of, referred to or participated in the planning for use of, and will not use, authorize use of, refer to or participate in the planning for use of, any “free writing prospectus,” as defined in Rule 405 under the Securities Act (which term includes use of any written information furnished to the Commission by the Company and not incorporated by reference into the Registration Statement and any press release issued by the Company) other than (i) a free writing prospectus that contains no “issuer information” (as defined in Rule 433(h)(2) under the Securities Act) that was not included (including through incorporation by reference) in the Preliminary Prospectus included in the Time of Sale Information or a previously filed Issuer Free Writing Prospectus, (ii) any Issuer Free Writing Prospectus listed on Annex A or prepared pursuant to Section 3(c) or Section 4(c) above (including any electronic road show), or (iii) any free writing prospectus prepared by such underwriter and approved by the Company in advance in writing (each such free writing prospectus referred to in clauses (i) or (iii), an “Underwriter Free Writing Prospectus”).

(b) It has not and will not, without the prior written consent of the Company, use any free writing prospectus that contains the final terms of the Securities unless such terms have previously been included in a free writing prospectus filed with the Commission; provided that Underwriters may use a term sheet substantially in the form of Annex B hereto without the consent of the Company; provided further that any Underwriter using such term sheet shall notify the Company, and provide a copy of such term sheet to the Company, prior to, or substantially concurrently with, the first use of such term sheet.

(c) It is not subject to any pending proceeding under Section 8A of the Securities Act with respect to the offering (and will promptly notify the Company if any such proceeding against it is initiated during the Prospectus Delivery Period).

6. Conditions of Underwriters’ Obligations. The obligation of each Underwriter to purchase the Underwritten Securities on the Closing Date or the Option Securities on the Additional Closing Date, as the case may be, as provided herein is subject to the performance by the Company of its covenants and other obligations hereunder and to the following additional conditions:

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(a) Registration Compliance; No Stop Order. No order suspending the effectiveness of the Registration Statement shall be in effect, and no proceeding for such purpose, pursuant to Rule 401(g)(2) or pursuant to Section 8A under the Securities Act shall be pending before or threatened by the Commission; the Prospectus and each Issuer Free Writing Prospectus shall have been timely filed with the Commission under the Securities Act (in the case of an Issuer Free Writing Prospectus, to the extent required by Rule 433 under the Securities Act) and in accordance with Section 4(a) hereof; and all requests by the Commission for additional information shall have been complied with to the reasonable satisfaction of the Underwriters.

(b) Representations and Warranties. The representations and warranties of the Company contained herein shall be true and correct on the date hereof and on and as of the Closing Date or the Additional Closing Date, as the case may be; and the statements of the Company and its officers made on behalf of the Company in any certificates delivered pursuant to this Agreement shall be true and correct on and as of the Closing Date or the Additional Closing Date, as the case may be.

(c) No Material Adverse Change. No event or condition of a type described in Section 3(g) hereof shall have occurred or shall exist, which event or condition is not described in the Time of Sale Information (excluding any amendment or supplement thereto) and the Prospectus (excluding any amendment or supplement thereto) and the effect of which in the judgment of the Underwriters makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Securities on the Closing Date or the Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Time of Sale Information and the Prospectus.

(d) Officer’s Certificate. The Underwriters shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, a certificate on behalf of the Company of the chief financial officer or chief accounting officer of the Company and one additional senior executive officer of the Company who is reasonably satisfactory to the Underwriters (provided that the chief executive officer of the Company shall be deemed satisfactory) (i) confirming that such officers have carefully reviewed the Registration Statement, the Time of Sale Information and the Prospectus and, to the knowledge of such officers, the representations of the Company set forth in Sections 3(b) and 3(d) hereof are true and correct, (ii) confirming that the other representations and warranties of the Company in this Agreement are true and correct and that the Company has complied with all agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date or the Additional Closing Date, as the case may be, and (iii) to the effect set forth in paragraphs (a) and (c) above.

(e) Comfort Letters. On the date of this Agreement and on the Closing Date or the Additional Closing Date, as the case may be, Ernst & Young LLP shall have furnished to the Underwriters, at the request of the Company, letters, dated the respective dates of delivery thereof and addressed to the Underwriters, in form and substance reasonably satisfactory to the Underwriters, containing statements and information of the type customarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus; provided, that the letter delivered on the Closing Date or the Additional Closing Date, as the case may be, shall use a “cut-off” date no more than three business days prior to such Closing Date or such Additional Closing Date, as the case may be.

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(f) Opinion and Negative Assurance Letter of Counsel for the Company. Willkie Farr & Gallagher LLP, counsel for the Company, shall have furnished to the Underwriters, at the request of the Company, their written opinion and negative assurance letter, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Underwriters, in the form set forth in Annex C-1 hereto.

(g) [Intentionally omitted].

(h) Opinion of Intellectual Property Counsel for the Company. Swanson & Bratschun, L.L.C., intellectual property counsel for the Company, shall have furnished to the Underwriters, at the request of the Company, their written opinion, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Underwriters, in the form set forth in Annex C-2 hereto.

(i) Opinion and Negative Assurance Letter of Counsel for the Underwriters. The Underwriters shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, an opinion and negative assurance letter of Latham & Watkins LLP, counsel for the Underwriters, with respect to such matters as the Underwriters may reasonably request, and such counsel shall have received such documents and information as they may reasonably request to enable them to pass upon such matters.

(j) No Legal Impediment to Issuance. 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 Closing Date or the Additional Closing Date, as the case may be, prevent the issuance or sale of the Securities; and no injunction or order of any federal, state or foreign court shall have been issued that would, as of the Closing Date or the Additional Closing Date, as the case may be, prevent the issuance or sale of the Securities.

(k) Good Standing . The Underwriters shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, satisfactory evidence of the good standing (where such concept is recognized) of the Company and its subsidiaries in their respective jurisdictions of organization and their good standing as foreign entities in the jurisdictions set forth on Annex D hereto, in each case in writing or any standard form of telecommunication from the appropriate governmental authorities of such jurisdictions.

(l) Exchange Listing. An application for the listing of the Underlying Securities shall have been submitted to the Exchange.

(m) Lock-up Agreements . The “lock-up” agreements, each substantially in the form of Exhibit A hereto, between you and the executive officers and directors of the Company relating to sales and certain other dispositions of shares of Stock or certain other securities, delivered to you on or before the date hereof, shall be full force and effect on the Closing Date or Additional Closing Date, as the case may be.

(n) DTC . The Securities shall be eligible for clearance and settlement through DTC.

(o) Additional Documents. On or prior to the Closing Date or the Additional Closing Date, as the case may be, the Company shall have furnished to the Underwriters such further certificates and documents as the Underwriters may reasonably request.

All letters, certificates and evidence mentioned above or elsewhere in this Agreement shall be deemed to be in compliance with the provisions hereof only if they are in form and substance reasonably satisfactory to counsel for the Underwriters.

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7. Indemnification and Contribution .

(a) Indemnification of the Underwriters. The Company agrees to indemnify and hold harmless each Underwriter, its directors and officers, those of its affiliates that have assisted in the distribution of the Securities hereunder and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, reasonable legal fees and other expenses incurred in connection with any suit, action or proceeding or any claim asserted, as such reasonable fees and expenses are incurred), joint or several, 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 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 Issuer Free Writing Prospectus, any “issuer information” filed or required to be filed pursuant to Rule 433(d) under the Securities Act or any Time of Sale Information (including any Time of Sale Information that has subsequently been amended), 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 furnished to the Company in writing by such Underwriter expressly for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in subsection (b) below.

(b) Indemnification of the Company. Each Underwriter 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 Securities 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 furnished to the Company in writing by such Underwriter expressly for use in the Registration Statement, the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus or any Time of Sale Information, it being understood and agreed upon that the only such information furnished by any Underwriter consists of the following information in the Prospectus furnished on behalf of each Underwriter: the information contained in the first and second sentences of the third paragraph under the caption “Underwriting” and the information contained in the third and fourth sentences of the tenth paragraph and the eleventh, twelfth and thirteenth paragraphs under the caption “Underwriting.”

(c) Notice and Procedures. 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 paragraph (a) or (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 paragraph (a) or (b) above 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 paragraph (a) or (b) above. If any such

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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 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) in the opinion of counsel to the Indemnified Person there may be legal defenses available to the Indemnified Person 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) include 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 interest between them. It is understood and agreed that the Indemnifying Person shall not, in connection with any proceeding or related proceedings 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 all Indemnified Persons, and that all such reasonable fees and expenses shall be paid or reimbursed as they are incurred. Any such separate firm for any Underwriter, its affiliates, directors and officers and any control persons of such Underwriter shall be designated in writing by the Underwriters and any such separate firm for the Company, its directors, its officers who signed the Registration Statement and any control persons of the Company 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. Notwithstanding the foregoing sentence, if at any time an Indemnified Person shall have requested that an Indemnifying Person reimburse the Indemnified Person for fees and expenses of counsel as contemplated by this paragraph, the Indemnifying Person shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 45 days after receipt by the Indemnifying Person of such request and (ii) the Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement. 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 would have been a party and indemnification would 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.

(d) Contribution. If the indemnification provided for in paragraphs (a) and (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 paragraph, 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 Underwriters on the other, from the offering of the Securities 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 Underwriters 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

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the one hand, and the Underwriters on the other, shall be deemed to be in the same respective proportions as the net proceeds (before deducting expenses but after deducting underwriting discounts and commissions) received by the Company from the sale of the Securities and the total underwriting discounts and commissions received by the Underwriters in connection therewith, in each case as set forth in the table on the cover of the Prospectus, bear to the aggregate offering price of the Securities. The relative fault of the Company, on the one hand, and the Underwriters, 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 or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

(e) Limitation on Liability. The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to paragraph (d) above were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take account of the equitable considerations referred to in paragraph (d) above. The amount paid or payable by an Indemnified Person as a result of the losses, claims, damages and liabilities referred to in paragraph (d) above shall be deemed to include, subject to the limitations set forth above, any legal or other expenses, in each case, reasonably incurred by such Indemnified Person in connection with any such action or claim. Notwithstanding the provisions of paragraphs (d) and (e), in no event shall an Underwriter be required to contribute any amount in excess of the amount by which the total underwriting discounts and commissions received by such Underwriter with respect to the offering of the Securities exceeds the amount of any damages that such Underwriter 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 Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations to contribute pursuant to paragraphs (d) and (e) are several in proportion to their respective purchase obligations hereunder and not joint.

(f) Non-Exclusive Remedies. The remedies provided for in paragraphs (a) through (e) 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.

8. Effectiveness of Agreement . This Agreement shall become effective upon the execution and delivery hereof by the parties hereto.

9. Termination . This Agreement may be terminated in the absolute discretion of the Underwriters, by notice to the Company, if after the execution and delivery of this Agreement and on or prior to the Closing Date or, in the case of the Option Securities, prior to the Additional Closing Date: (i) trading generally shall have been suspended or materially limited on or by any of the New York Stock Exchange or the Exchange; (ii) trading of any securities issued or guaranteed by the Company 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 major disruption of settlements of securities, payment, or clearance services in the United States or any other country where such securities are listed or (v) 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, in the judgment of the Underwriters, is material and adverse and makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Securities on the Closing Date or the Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Time of Sale Information and the Prospectus. In the event this Agreement is terminated, the Underwriters shall contemporaneously terminate or waive in their entirety the lock-up agreements referred to in Section 6(m).

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10. Defaulting Underwriter .

(a) If, on the Closing Date or the Additional Closing Date, as the case may be, any Underwriter defaults on its obligation to purchase the Securities that it has agreed to purchase hereunder on such date, the non-defaulting Underwriters may in their discretion arrange for the purchase of such Securities by other persons satisfactory to the Company on the terms contained in this Agreement. If, within 36 hours after any such default by any Underwriter, the non-defaulting Underwriters do not arrange for the purchase of such Securities, then the Company shall be entitled to a further period of 36 hours within which to procure other persons satisfactory to the non-defaulting Underwriters to purchase such Securities on such terms. If other persons become obligated or agree to purchase the Securities of a defaulting Underwriter, either the non-defaulting Underwriters or the Company may postpone the Closing Date or the Additional Closing Date, as the case may be, for up to five full business days in order to effect any changes that in the opinion of counsel for the Company or counsel for the Underwriters may be necessary in the Registration Statement, the Time of Sale Information and the Prospectus or in any other document or arrangement, and the Company agrees to promptly prepare any amendment or supplement to the Registration Statement and the Prospectus that effects any such changes. As used in this Agreement, the term “Underwriter” includes, for all purposes of this Agreement unless the context otherwise requires, any person not listed in Schedule 1 hereto that, pursuant to this Section 10, purchases Securities that a defaulting Underwriter agreed but failed to purchase.

(b) If, after giving effect to any arrangements for the purchase of the Securities of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in paragraph (a) above, the aggregate number of Securities that remain unpurchased on the Closing Date or the Additional Closing Date, as the case may be, does not exceed one-eleventh of the aggregate number of Securities to be purchased on such date, then the Company shall have the right to require each non-defaulting Underwriter to purchase the number of Securities that such Underwriter agreed to purchase hereunder on such date plus such Underwriter’s pro rata share (based on the number of Securities that such Underwriter agreed to purchase on such date) of the Securities of such defaulting Underwriter or Underwriters for which such arrangements have not been made.

(c) If, after giving effect to any arrangements for the purchase of the Securities of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in paragraph (a) above, the aggregate number of Securities that remain unpurchased on the Closing Date or the Additional Closing Date, as the case may be, exceeds one-eleventh of the aggregate principal amount of Securities to be purchased on such date, or if the Company shall not exercise the right described in paragraph (b) above, then this Agreement or, with respect to any Additional Closing Date, the obligation of the Underwriters to purchase Securities on the Additional Closing Date, as the case may be, shall terminate without liability on the part of the non-defaulting Underwriters. Any termination of this Agreement pursuant to this Section 10 shall be without liability on the part of the Company, except that the Company and the Underwriters will continue to be liable for the payment of expenses as set forth in Section 11 hereof and except that the provisions of Section 7 hereof shall not terminate and shall remain in effect.

(d) Nothing contained herein shall relieve a defaulting Underwriter of any liability it may have to the Company or any non-defaulting Underwriter for damages caused by its default.

11. Payment of Expenses .

(a) Whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, the Company will pay or cause to be paid all costs and expenses incident to the performance of its obligations hereunder, including without limitation, (i) the costs incident to the

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authorization, issuance, sale, preparation and delivery of the Securities and any taxes payable in that connection; (ii) the costs incident to the preparation, printing and filing under the Securities Act of the Registration Statement, the Preliminary Prospectus, any Issuer Free Writing Prospectus, any Time of Sale Information and the Prospectus (including all exhibits, amendments and supplements thereto) and the distribution thereof; (iii) the fees and expenses of the Company’s counsel and independent accountants; (iv) the reasonable fees and expenses incurred in connection with the registration or qualification and determination of eligibility for investment of the Securities under the laws of such jurisdictions as the Underwriters may designate and the preparation, printing and distribution of a Blue Sky Memorandum (including the related reasonable fees and expenses of counsel for the Underwriters); (v) any fees charged by rating agencies for the Securities; (vi) the fees and expenses of the Trustee and the paying agent (including related reasonable fees and expenses of any counsel to such parties); (vii) all reasonable expenses and application fees incurred in connection with the approval of the Securities for book entry transfer by DTC and any filing with, and clearance of the offering by, the Financial Industry Regulatory Authority, Inc. (including the related fees and expenses of counsel for the Underwriters; provided , that such fees and expenses shall not exceed $10,000 in the aggregate); (viii) all expenses incurred by the Company in connection with any “road show” presentation to potential investors (other than as set forth in the next sentence); and (ix) all expenses and application fees related to the listing of the Underlying Securities on the Exchange. The Underwriters shall pay all of their own costs and expenses, including fees of their counsel, travel and lodging expenses of their representatives and 50% of the costs of any aircraft chartered in connection with any “road show.”

(b) If (i) this Agreement is terminated pursuant to Section 9, (ii) the Company for any reason fails to tender the Securities for delivery to the Underwriters (other than because of the Underwriters’ failure to pay for the Securities) or (iii) the Underwriters decline to purchase the Securities for any reason permitted under this Agreement, the Company agrees to reimburse the Underwriters (other than defaulting underwriters under Section 10) for all out-of-pocket costs and expenses (including the reasonable fees and expenses of their counsel) reasonably incurred by the Underwriters in connection with this Agreement and the offering contemplated hereby.

12. Persons Entitled to Benefit of Agreement . This Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and any controlling persons referred to in Section 7 hereof. Nothing in this 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 provision contained herein. No purchaser of Securities from any Underwriter shall be deemed to be a successor merely by reason of such purchase.

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

14. Certain Defined Terms . For purposes of this Agreement, (a) except where otherwise expressly provided, the term “affiliate” has the meaning set forth in Rule 405 under the Securities Act; (b) 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 (c) the term “subsidiary” has the meaning set forth in Rule 405 under the Securities Act.

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15. Compliance with the 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)), the Underwriters are required to obtain, verify and record information that identifies their respective clients, including the Company, which information may include the name and address of their respective clients, as well as other information that will allow the Underwriters to properly identify their respective clients.

16. Miscellaneous .

(a) Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted and confirmed by any standard form of telecommunication. Notices to the Underwriters shall be given to c/o J. P. Morgan Securities LLC, 383 Madison Avenue, New York, New York 10179 (fax: (212) 622-8358), Attention: Equity Syndicate Desk and Merrill Lynch, Pierce, Fenner & Smith Incorporated, One Bryant Park, New York, New York 10036, Attention: Syndicate Department (facsimile: (646) 855-3073), with a copy to ECM Legal (facsimile: (212) 230-8730), with a copy to Latham & Watkins LLP, 12670 High Bluff Drive, San Diego, CA 92130, Attention: Cheston J. Larson and Michael E. Sullivan. Notices to the Company shall be given to it at 5500 Flatiron Parkway, Suite 100, Boulder, Colorado 80301 (fax: (303) 245-0360); Attention: Paul Gross, with a copy to Willkie Farr & Gallagher LLP, 787 Seventh Avenue, New York, NY 10019 (fax: (212) 728-8111); Attention: Thomas Mark.

(b) Governing Law. This Agreement and any claim, controversy or dispute arising under or related to this Agreement shall be governed by and construed in accordance with the laws of the State of New York applicable to agreements made and to be performed in such state.

(c) Counterparts. This 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.

(d) Amendments or Waivers. No amendment or waiver of any provision of this 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.

(e) Headings. The headings herein 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.

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If the foregoing is in accordance with your understanding, please indicate your acceptance of this Agreement by signing in the space provided below.

Accepted: As of the date first written above

For themselves and on behalf of the

several Underwriters listed

in Schedule 1 hereto.

[Signature Page - Underwriting Agreement]

Annex A

a. Time of Sale Information

Press release announcing the offering, issued by the Company on April 16, 2018.

Press release announcing the pricing of the offering, issued by the Company on April 16, 2018.

Term sheet containing the terms of the Securities, substantially in the form of Annex B.

Annex B

Clovis Oncology, Inc.

Pricing Term Sheet

[Attached]

Free Writing Prospectus

Filed pursuant to Rule 433

Registration Statement No. 333-215400

Dated April 16, 2018

Supplementing the

Preliminary Prospectus Supplements dated April 16, 2018

(To Prospectus dated April 16, 2018)

PRICING TERM SHEET

April 16, 2018

Clovis Oncology, Inc.

Offerings of

$300,000,000 Aggregate Principal Amount of

1.25% Convertible Senior Notes due 2025

and

1,837,898 Shares of Common Stock

The information in this pricing term sheet relates to the offering by Clovis Oncology, Inc. of its 1.25% Convertible Senior Notes due 2025 (the “Notes Offering”) and the offering by Clovis Oncology, Inc. of shares of its common stock, par value $0.001 per share (the “Common Stock Offering”), and should be read together with the preliminary prospectus supplement, dated April 16, 2018, relating to the Notes Offering (the “Notes Offering Preliminary Prospectus Supplement”), or the preliminary prospectus supplement, dated April 16, 2018, relating to the Common Stock Offering (the “Common Stock Offering Preliminary Prospectus Supplement” and, together with the Notes Offering Preliminary Prospectus Supplement, the “Prospectus Supplements”). The information in this pricing term sheet supersedes the information in the applicable Preliminary Prospectus Supplement to the extent inconsistent with the information in such Preliminary Prospectus Supplement. Terms used, but not defined, in this pricing term sheet have the respective meanings set forth in the applicable Preliminary Prospectus Supplement. As used in this pricing term sheet, “we,” “our” and “us” refer to Clovis Oncology, Inc. and not to its subsidiaries.

The Notes Offering and the Common Stock Offering are separate offerings that are being made pursuant to separate prospectus supplements. The closing of the Notes Offering is not conditioned upon the closing of the Common Stock Offering, and the closing of the Common Stock Offering is not conditioned upon the closing of the Notes Offering.

Merrill Lynch, Pierce, Fenner & Smith

                     Incorporated

Notes Offering

Merrill Lynch, Pierce, Fenner & Smith

                     Incorporated

The exact stock prices and effective dates or redemption notice dates may not be set forth in the table above, in which case:

Notwithstanding the foregoing, in no event will the conversion rate per $1,000 principal amount of Notes exceed 18.3789 shares of Common Stock, subject to adjustment in the same manner as the conversion rate as set forth in the Notes Offering Preliminary Prospectus Supplement under the caption “Description of notes—Conversion rights—Conversion rate adjustments.”

* * *

The Issuer has filed a preliminary prospectus supplement and a registration statement (including a prospectus) with the Securities and Exchange Commission (the “SEC”) for each offering to which this communication relates. Before you invest, you should read the applicable preliminary prospectus supplement and the prospectus in that registration statement and other documents the Issuer has filed with the SEC for more complete information about the Issuer and these offerings. You may get these documents for free by visiting EDGAR on the SEC website at www.sec.gov . Alternatively, any underwriter or any dealer participating in these offerings will arrange to send you the applicable preliminary prospectus supplement and the prospectus upon request to J.P. Morgan Securities LLC, Attention: c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY 11717, or (866) 803-9204; or Merrill Lynch, Pierce, Fenner & Smith Incorporated, at (800) 294-1322.

ANY DISCLAIMERS OR OTHER NOTICES THAT MAY APPEAR BELOW ARE NOT APPLICABLE TO THIS COMMUNICATION AND SHOULD BE DISREGARDED. SUCH DISCLAIMERS OR OTHER NOTICES WERE AUTOMATICALLY GENERATED AS A RESULT OF THIS COMMUNICATION BEING SENT VIA BLOOMBERG OR ANOTHER EMAIL SYSTEM.

Annex C-1

Form of Opinion of Counsel for the Company

[Attached]

Annex C-2

Form of Opinion of Intellectual Property Counsel for the Company

[Attached]

Annex D

Foreign Qualifications

Colorado

California

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Exhibit A

LOCK-UP AGREEMENT

March    , 2018

J.P. MORGAN SECURITIES LLC

MERRILL LYNCH, PIERCE, FENNER & SMITH

                INCORPORATED

c/o

J.P. Morgan Securities LLC

383 Madison Avenue

New York, New York 10179

Merrill Lynch, Pierce, Fenner & Smith

                Incorporated

One Bryant Park

New York, New York 10036

Re:    Clovis Oncology, Inc. — Public Offering

Ladies and Gentlemen:

The undersigned understands that you propose to enter into an underwriting agreement (the “ Underwriting Agreement ”) with Clovis Oncology, Inc., a Delaware corporation (the “ Company ”), providing for the public offering (the “ Public Offering ”) by us (the “ Underwriters ”) of Convertible Senior Notes due 2025 (the “ Securities ”). Capitalized terms used herein and not otherwise defined shall have the meanings set forth in the Underwriting Agreement.

In consideration of the Underwriters’ agreement to purchase and make the Public Offering of the Securities, and for other good and valuable consideration, the receipt of which is hereby acknowledged, the undersigned hereby agrees that, without the prior written consent of the Underwriters, the undersigned will not, during the period beginning on the date of this letter agreement (this “ Letter Agreement ”) and ending 60 days after the date of the final prospectus relating to the Public Offering (the “ Prospectus ” and such period, the “ Lock-Up Period ”), (1) 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, or otherwise transfer or dispose of, directly or indirectly, any shares of common stock, $0.001 per share par value, of the Company (the “ Common Stock ”) or any securities convertible into or exercisable or exchangeable for Common Stock (including, without limitation, Common Stock or such other securities which may be deemed to be beneficially owned (as a result of the power to dispose) by the undersigned in accordance with the rules and regulations of the Securities and Exchange Commission and securities which may be issued upon exercise of a stock option or warrant), or publicly disclose

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the intention to make any offer, sale, pledge or disposition, (2) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Common Stock or such other securities, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise or (3) make any demand for or exercise any right with respect to the registration of any shares of Common Stock or any security convertible into or exercisable or exchangeable for Common Stock, in each case other than (A) transfers as a bona fide gift or gifts, (B) if the undersigned is a partnership, limited liability company or corporation, distributions to partners, members or stockholders of the undersigned, (C) transfers to any trust for the direct or indirect benefit of the undersigned or a member of the immediate family of the undersigned, (D) transfers to any corporation, partnership, limited liability company or other entity all of the beneficial ownership interests of which are held by the undersigned, (E) transfers by will, other testamentary document or intestate succession to the legal representative, heir, beneficiary or a member of the immediate family of the undersigned, (F) transfers to any affiliate of the undersigned or any investment fund or other entity controlled or managed by the undersigned, (G) the establishment of any contract, instruction or plan that satisfies all of the requirements of Rule 10b5-1 (a “ Rule 10b5-1 Plan ”) under the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”); provided , however , that no sales of Common Stock or securities convertible into, or exchangeable or exercisable for, Common Stock, shall be made pursuant to such Rule 10b5-1 Plan prior to the expiration of the Lock-Up Period referred to above, (H) transfers or sales of Common Stock pursuant to any contract, instruction or plan, including a Rule 10b5-1 Plan that has been entered into by the undersigned prior to the date of this Letter Agreement or any amendment or replacement of any such contract, instruction or plan, so long as the number of shares of Common Stock subject to such contract, instruction or plan is not increased or (I) transfers or sales of Common Stock to cover tax withholding obligations in connection with the vesting event of restricted stock units; provided that the remaining shares of Common Stock received upon settlement of such restricted stock units shall be subject to the restrictions on transfers set forth in this Letter Agreement; provided that, in the case of any transfer or distribution pursuant to clause (A), (B), (C), (D) or (F), each donee, transferee or distributee shall execute and deliver to the Underwriters prior to such transfer a lock-up letter in the form of this Letter Agreement; provided , further , that, in the case of any transfer or distribution pursuant to clause (A), (B), (C), (D) or (F), no filing by any party (donor, donee, transferor or transferee) under the Exchange Act, or other public announcement shall be required or shall be made voluntarily in connection with such transfer or distribution (other than after the expiration of the Lock-Up Period and other than, in the case of a transfer pursuant to clause (A), the filing of a Form 5); and provided further , that any transfer or distribution pursuant to clause (A), (B), (C), (D) or (F) shall not involve a disposition for value.

Furthermore, notwithstanding the restrictions imposed by this Letter Agreement, the undersigned may, without the prior written consent of the Underwriters, exercise an option to purchase shares of Common Stock granted under any stock incentive plan or stock purchase plan of the Company, so long as the shares issued upon such exercise are subject to the requirements of this Letter Agreement. For purposes of this Letter Agreement, “immediate family” shall mean any relationship by blood, marriage or adoption, not more remote than first cousin.

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In furtherance of the foregoing, the Company, and any duly appointed transfer agent for the registration or transfer of the securities described herein, are hereby authorized to decline to make any transfer of securities if such transfer would constitute a violation or breach of this Letter Agreement.

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Letter Agreement. All authority herein conferred or agreed to be conferred and any obligations of the undersigned shall be binding upon the successors, assigns, heirs or personal representatives of the undersigned.

The undersigned understands that, if the Underwriting Agreement does not become effective by April 26, 2018, or if prior to such date the Underwriters, on the one hand, or the Company, on the other hand, informs the other(s) in writing that they have determined not to proceed with the Public Offering, or if the Underwriting Agreement (other than the provisions thereof which survive termination) shall terminate or be terminated prior to payment for and delivery of the Securities to be sold thereunder, the undersigned shall be released from all obligations under this Letter Agreement. The undersigned understands that the Underwriters are entering into the Underwriting Agreement and proceeding with the Public Offering in reliance upon this Letter Agreement.

This Letter Agreement and any claim, controversy or dispute arising under or related to this Letter Agreement shall be governed by and construed in accordance with the laws of the State of New York, without regard to the conflict of laws principles thereof.

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