EXHIBIT 1.1

18,000,000 Shares

Array BioPharma Inc.

UNDERWRITING AGREEMENT

November 9, 2012

JEFFERIES & COMPANY, INC.
J.P. MORGAN SECURITIES LLC
As Representatives of the several Underwriters

c/o JEFFERIES & COMPANY, INC.
520 Madison Avenue
New York, New York  10022

and

c/o J.P. MORGAN SECURITIES LLC
383 Madison Avenue
New York, New York 10179

Ladies and Gentlemen:

Introductory.  Array BioPharma Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of 18,000,000 shares of its common stock, par value $0.001 per share (the “Shares”).  The 18,000,000 Shares to be sold by the Company are called the “Firm Shares.”  In addition, the Company has granted to the Underwriters an option to purchase up to an additional 2,700,000 Shares as provided in Section 2.  The additional 2,700,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.”  The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.”  Jefferies & Company, Inc. (“Jefferies”) and J.P. Morgan Securities LLC (“J.P. Morgan”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters.

The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-3, File No. 333-178162, including a base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares.  Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it became effective under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.”  Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of any

such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement.  The preliminary prospectus supplement dated November 8, 2012, describing the Offered Shares and the offering thereof (the “Preliminary Prospectus Supplement”), together with the Base Prospectus, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus supplement to the Base Prospectus in preliminary form that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below), together with the Base Prospectus, is called a “preliminary prospectus.”  As used herein, the term “Prospectus” shall mean the final prospectus supplement to the Base Prospectus that describes the Offered Shares and the offering thereof (the “Final Prospectus Supplement”), together with the Base Prospectus, in the form first used by the Underwriters to confirm sales of the Offered Shares or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act.  References herein to the Preliminary Prospectus, any preliminary prospectus and the Prospectus shall refer to both the prospectus supplement and the Base Prospectus components of such prospectus.  As used herein, “Applicable Time” is 8:00 am (New York time) on November 9, 2012.   As used herein, “free writing prospectus” has the meaning set forth in Rule 405 under the Securities Act, and “Time of Sale Prospectus” means the Preliminary Prospectus, as amended or supplemented immediately prior to the Applicable Time, together with the free writing prospectuses, if any, identified in Schedule B hereto and the pricing information identified in Schedule C hereto. As used herein, “Road Show” means a “road show” (as defined in Rule 433 under the Securities Act) relating to the offering of the Offered Shares contemplated hereby that is a “written communication” (as defined in Rule 405 under the Securities Act).  All references in this Agreement to the Registration Statement, the Preliminary Prospectus, any preliminary prospectus, the Base Prospectus and the Prospectus shall include the documents incorporated or deemed to be incorporated by reference therein.  All references in this Agreement to financial statements and schedules and other information which are “contained,” “included” or “stated” in, or “part of” the Registration Statement, the Rule 462(b) Registration Statement, the Preliminary Prospectus, any preliminary prospectus, the Base Prospectus, the Time of Sale Prospectus or the Prospectus, and all other references of like import, shall be deemed to mean and include all such financial statements and schedules and other information which is or is deemed to be incorporated by reference in the Registration Statement, the Rule 462(b) Registration Statement, the Preliminary Prospectus, any preliminary prospectus, the Base Prospectus, the Time of Sale Prospectus or the Prospectus, as the case may be.  All references in this Agreement to amendments or supplements to the Registration Statement, the Preliminary Prospectus, any preliminary prospectus, the Base Prospectus, the Time of Sale Prospectus or the Prospectus  shall be deemed to mean and include the filing of any document under the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”) that is or is deemed to be incorporated by reference in the Registration Statement, the Preliminary Prospectus, any preliminary prospectus, the Base Prospectus, or the Prospectus, as the case may be.  All references in this Agreement to (i) the Registration Statement, the Preliminary Prospectus, any preliminary prospectus, the Base Prospectus or the Prospectus, any amendments or supplements to any of the foregoing, or any free writing prospectus, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“EDGAR”) and (ii) the Prospectus shall be deemed to include any “electronic Prospectus” provided for use in connection with the offering of the Offered Shares as contemplated by Section 3(n) of this Agreement.

In the event that the Company has only one subsidiary, then all references herein to “subsidiaries” of the Company shall be deemed to refer to such single subsidiary, mutatis mutandis.

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The Company hereby confirms its agreements with the Underwriters as follows:

Section 1.              Representations and Warranties of the Company.

The Company hereby represents, warrants and covenants to each Underwriter, as of the date of this Agreement, as of the First Closing Date (as hereinafter defined) and as of each Option Closing Date (as hereinafter defined), if any, as follows:

(a)           Compliance with Registration Requirements.  The Registration Statement has become effective under the Securities Act.  The Company has complied, to the Commission’s satisfaction, with all requests of the Commission for additional or supplemental information, if any.  No stop order suspending the effectiveness of the Registration Statement is in effect and no proceedings for such purpose have been instituted or are pending or, to the best knowledge of the Company, are contemplated or threatened by the Commission. At the time the Company’s Annual Report on Form 10-K for the year ended June 30, 2012 (the “Annual Report”) was filed with the Commission, or, if later, at the time the Registration Statement was originally filed with the Commission, the Company met the then-applicable requirements for use of Form S-3 under the Securities Act. The Company meets the requirements for use of Form S-3 under the Securities Act specified in Financial Industry Regulatory Authority, Inc. (“FINRA”) Conduct Rule 5110(B)(7)(C)(i). The documents incorporated or deemed to be incorporated by reference in the Registration Statement, the Time of Sale Prospectus and the Prospectus, at the time they were or hereafter are filed with the Commission or became effective under the Exchange Act, as the case may be, complied and will comply in all material respects with the requirements of the Exchange Act.

(b)           Disclosure. Each preliminary prospectus and the Prospectus when filed complied in all material respects with the Securities Act and, if filed by electronic transmission pursuant to EDGAR, was identical (except as may be permitted by Regulation S-T under the Securities Act) to the copy thereof delivered to the Underwriters for use in connection with the offer and sale of the Offered Shares.  Each of the Registration Statement and any post-effective amendment thereto, at the time it became or becomes effective and at all subsequent times, 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 to make the statements therein not misleading.  As of the Applicable Time, the Time of Sale Prospectus (including any preliminary prospectus wrapper)  did not, and at the time of each sale of the Offered Shares and at the First Closing Date (as defined in Section 2), the Time of Sale Prospectus, as then amended or supplemented by the Company, if applicable, 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.  The Prospectus (including any Prospectus wrapper), as of its date and (as then amended or supplemented) at all subsequent times, did not 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.  The representations and warranties set forth in the three immediately preceding sentences do not apply to statements in or omissions from the Registration Statement or any post-effective amendment thereto, or the Prospectus or the Time of Sale Prospectus, or any amendments or supplements thereto, made in reliance upon and in conformity with written information relating to any Underwriter furnished to the Company in writing by the Representatives expressly for use therein, it being understood and agreed that the only such information consists of the information described in Section 9(b) below.  There are no contracts or other documents required to be described in the Time of Sale Prospectus

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or the Prospectus or to be filed as an exhibit to the Registration Statement which have not been described or filed as required.

(c)           Free Writing Prospectuses; Road Show. As of the determination date referenced in Rule 164(h) under the Securities Act, the Company was not, is not or will not be (as applicable) an “ineligible issuer” in connection with the offering of the Offered Shares pursuant to Rules 164, 405 and 433 under the Securities Act.  Each free writing prospectus that the Company is required to file pursuant to Rule 433(d) under the Securities Act has been, or will be, filed with the Commission in accordance with the requirements of the Securities Act.  Each free writing prospectus that the Company has filed, or is required to file, pursuant to Rule 433(d) under the Securities Act or that was prepared by or on behalf of or used or referred to by the Company complies or will comply in all material respects with the requirements of Rule 433 under the Securities Act, including timely filing with the Commission or retention where required and legending, and each such free writing prospectus, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Offered Shares did not, does not and will not include any information that conflicted, conflicts or will conflict with the information contained in the Registration Statement, the Prospectus or any preliminary prospectus and not superseded or modified.  Except for the free writing prospectuses, if any, identified in Schedule B, and electronic road shows, if any, furnished to you before first use, the Company has not prepared, used or referred to, and will not, without your prior written consent, prepare, use or refer to, any free writing prospectus.  Each Road Show, when considered together with the Time of Sale Prospectus, does 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.

(d)           Offering Materials Furnished to Underwriters.  The Company has delivered to each of the Representatives two complete copies of the Registration Statement and each amendment thereto (including, in each case, exhibits) and each consent and certificate of experts filed as a part thereof, and additional copies of the Registration Statement and each amendment thereto (without exhibits) and each preliminary prospectus and any free writing prospectus reviewed and consented to by the Representatives, in such quantities and at such places as the Representatives have reasonably requested for each of the Underwriters.  Upon request of the Representatives, the Company will provide to the Underwriters two complete, manually signed copies of the Registration Statement and each amendment thereto.

(e)           Distribution of Offering Material By the Company.  Prior to the later of (i) the expiration or termination of the option granted to the several Underwriters in Section 2 and (ii) the completion of the Underwriters’ distribution of the Offered Shares, the Company has not distributed and will not distribute any offering material in connection with the offering and sale of the Offered Shares other than the Registration Statement, the Time of Sale Prospectus, the Prospectus or any free writing prospectus reviewed and consented to by the Representatives.

(f)            The Underwriting Agreement.  This Agreement has been duly authorized, executed and delivered by the Company.  The execution, delivery and performance of this Agreement and the consummation of the transactions herein and therein contemplated will not result in a breach or violation of any of the terms and provisions of, or constitute a default under, any statute, any agreement or instrument to which the Company is a party or by which it is bound or to which any of its property is subject, the Company’s charter or bylaws, or any order, rule, regulation or decree of any court or governmental agency or body having jurisdiction over the Company or any of its properties; no consent, approval, authorization or order of, or filing with, any court or governmental agency or body is required for the execution, delivery and

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performance of this Agreement or for the consummation of the transactions contemplated hereby and thereby, including the issuance or sale of the Shares by the Company, except such as may be required under the Securities Act or state securities or blue sky laws; and the Company has and will have full power and authority to enter into this Agreement and to authorize, issue and sell the Shares as contemplated hereby and thereby.

(g)           No Material Adverse Change.  Except as otherwise disclosed in the Registration Statement, the Time of Sale Prospectus and the Prospectus, subsequent to the respective dates as of which information is given in the Registration Statement, the Time of Sale Prospectus and the Prospectus, the Company and its subsidiaries, considered as one entity, have not incurred any material liabilities or obligations, direct or contingent, or entered into any material transactions, or declared or paid any dividends or made any distribution of any kind with respect to their capital stock; and there has not been any change in the capital stock, or issuance of options, warrants, convertible securities or other rights to purchase the capital stock (other than due to the issuance, redemption or forfeiture of any shares of capital stock, or options, warrants, convertible securities or other rights to purchase capital stock, under any stock option or incentive, stock purchase or similar employee benefit plans described in the Time of Sale Prospectus, including upon the exercise of outstanding options, or pursuant to the terms of outstanding warrants, or in satisfaction of outstanding debt of the Company as described in the Time of Sale Prospectus (collectively, “Additional Issuances”)), or any material change in the short-term or long-term debt, of the Company and its subsidiaries, considered as one entity, or any material adverse change, or any development that could reasonably be expected to result in a material adverse change, in the condition, financial or otherwise, or in the earnings, business, properties, operations or prospects, whether or not arising from transactions in the ordinary course of business, of the Company and its subsidiaries, considered as one entity (any such change being referred to herein as a “Material Adverse Change”) or any development that would reasonably be expected to result in a Material Adverse Change.

(h)           Independent Accountants.  To the Company’s knowledge, KPMG LLP, which has expressed its opinion with respect to the financial statements (which term as used in this Agreement includes the related notes thereto) and supporting schedules filed with the Commission as a part of the Registration Statement, the Time of Sale Prospectus and the Prospectus, is (i) an independent registered public accounting firm as required by the Securities Act, the Exchange Act and the rules of the Public Company Accounting Oversight Board (“PCAOB”), (ii) in compliance with the applicable requirements relating to the qualification of accountants under Rule 2-01 of Regulation S-X under the Securities Act and (iii) a registered public accounting firm as defined by the PCAOB whose registration has not been suspended or revoked and who has not requested such registration to be withdrawn.

(i)            Financial Statements.  The financial statements of the Company, together with the related notes, set forth or incorporated by reference in the Registration Statement and included in the Time of Sale Prospectus and the Prospectus comply in all material respects with the requirements of the Securities Act and the Exchange Act and fairly present the financial condition of the Company as of the dates indicated and the results of operations and changes in cash flows for the periods therein specified in conformity with generally accepted accounting principles consistently applied throughout the periods involved; and the supporting schedules included in the Registration Statement present fairly the information required to be stated therein.  The interactive data in eXtensible Business Reporting Language included or 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. No other financial statements or supporting schedules are required to be included in the

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Registration Statement, the Time of Sale Prospectus or the Prospectus.  All disclosures contained in the Registration Statement, any preliminary prospectus, the Prospectus and any free writing prospectus that constitute non-GAAP financial measures (as defined by the rules and regulations under the Securities Act and the Exchange Act) comply with Regulation G under the Exchange Act and Item 10 of Regulation S-K under the Securities Act, as applicable. To the Company’s knowledge, no person who has been suspended or barred from being associated with a registered public accounting firm, or who has failed to comply with any sanction pursuant to Rule 5300 promulgated by the PCAOB, has participated in or otherwise aided the preparation of, or audited, the financial statements, supporting schedules or other financial data filed with the Commission as a part of the Registration Statement, the Time of Sale Prospectus and the Prospectus.

(j)            Company’s Accounting System.  The Company and each of its subsidiaries make and keep accurate books and records and 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 authorization; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles as applied in the United States and to maintain accountability for assets; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) the recorded accountability for assets is compared with existing assets at reasonable intervals and appropriate action is taken with respect to any differences.  Except as described in the Registration Statement, the Time of Sale Prospectus and the Prospectus, since the most recent audit of the effectiveness of the Company’s internal control over financial reporting, there has been (i) no material weakness in the Company’s internal control over financial reporting (whether or not remediated) and (ii) no change in the Company’s internal control over financial reporting that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting.  The Company is not aware of any change in its internal control over financial reporting that has occurred during its most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting.

(k)           Disclosure Controls and Procedures; Deficiencies in or Changes to Internal Control Over Financial Reporting. The Company has established and maintains disclosure controls and procedures (as defined in Rules 13a-14 and 15d-14 under the Exchange Act) and such controls and procedures are effective in ensuring that material information relating to the Company is made known to the principal executive officer and the principal financial officer.  The Company has utilized such controls and procedures in preparing and evaluating the disclosures in the Registration Statement, the Time of Sale Prospectus and the Prospectus.

(l)            Incorporation and Good Standing of the Company.  The Company has been duly organized and is validly existing as a corporation in good standing under the laws of its jurisdiction of incorporation. The Company has full corporate power and authority to own its properties and conduct its business as currently being carried on and as described in the Registration Statement, the Time of Sale Prospectus and the Prospectus, and is duly qualified to do business as a foreign corporation in good standing in each jurisdiction in which it owns or leases real property or in which the conduct of its business makes such qualification necessary and in which the failure to so qualify would have a material adverse effect upon the business, prospects, management, properties, operations, condition (financial or otherwise) or results of operations of the Company (“Material Adverse Effect”).  All of the issued and outstanding capital stock or other equity or ownership interests of each of the Company’s subsidiaries have been duly authorized and validly issued, are fully paid and nonassessable and are owned by the

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Company, directly or through subsidiaries, free and clear of any security interest, mortgage, pledge, lien, encumbrance or adverse claim.

(m)          Capitalization and Other Capital Stock Matters.  All of the issued and outstanding shares of capital stock of the Company have been duly authorized and validly issued, are fully paid and nonassessable and have been issued in compliance with all federal and state securities laws.  None of the outstanding Shares was issued in violation of or is subject to any preemptive rights, rights of first refusal or other similar rights to subscribe for or purchase securities that have not been waived in writing, and the holders thereof are not subject to personal liability by reason of being such holders; the Offered Shares have been duly authorized and, when issued, delivered and paid for in accordance with the terms of this Agreement will have been validly issued and will be fully paid and nonassessable, and the holders thereof will not be subject to personal liability by reason of being such holders; and the capital stock of the Company, including the Shares, conforms to the description thereof in the Registration Statement and the Time of Sale Prospectus.  Except as otherwise stated in the Registration Statement and the Time of Sale Prospectus, there are no preemptive rights or other rights to subscribe for or to purchase, or any restriction upon the voting or transfer of, any Shares pursuant to the Company’s charter, by-laws or any agreement or other instrument to which the Company is a party or by which the Company is bound.  Neither the filing of the Registration Statement nor the offering or sale of the Shares as contemplated by this Agreement gives rise to any rights for or relating to the registration of any Shares or other securities of the Company, except for such rights as have been duly waived.  Except as described in the Registration Statement and the Time of Sale Prospectus and other than Additional Issuances, there are no options, warrants, agreements, contracts or other rights in existence to purchase or acquire from the Company any shares of the capital stock of the Company.  The Company has an authorized and outstanding capitalization as set forth in each the Registration Statement, the Time of Sale Prospectus and the Prospectus as of the dates set forth therein.

(n)           Stock Exchange Listing.  The Shares are registered pursuant to Section 12(b) of the Exchange Act and are included or approved for inclusion on The NASDAQ Global Market (the “NASDAQ”), and the Company has taken no action designed to, or likely to have the effect of, terminating the registration of the Shares under the Exchange Act or delisting the Shares from the NASDAQ, nor has the Company received any notification that the Commission or the NASDAQ is contemplating terminating such registration or listing. The Company has complied in all material respects with the applicable requirements of the NASDAQ for maintenance of inclusion of the Shares thereon. The Company has filed an application to include the Offered Shares on the NASDAQ.

(o)           Subsidiaries.  The Company has no subsidiaries other than Array BioPharma, Ltd., which subsidiary (a) has no material assets or liabilities and (b) is not a “significant subsidiary” within the meaning of Rule 1-02(w) of Regulation S-X under the Act.  The Company does not own, directly or indirectly, any shares of stock or any other equity or long-term debt securities of any other corporation or have any equity interest in any other corporation, partnership, joint venture, association, trust or other entity other than its minority interests in VentiRx Pharmaceuticals, Inc. and Cytomyx Holdings.

(p)           Non-Contravention of Existing Instruments; No Further Authorizations or Approvals Required.  Neither the Company nor any of its subsidiaries is (A) in violation of its charter or bylaws, or (B) in breach of or otherwise in default, and no event has occurred which, with notice or lapse of time or both, would constitute such a default in the performance of any material obligation, agreement or condition contained in any bond, debenture, note, indenture,

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loan agreement, mortgage, deed of trust or any other material contract, lease or other instrument to which it is subject or by which any of them may be bound, or to which any of the material property or assets of the Company is subject; or (C) 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 (B) and (C) above, as could not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(q)           Compliance with Laws.  The Company and its subsidiaries have been and are in compliance with all applicable laws, rules and regulations, except where the failure to be so in compliance could not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.

(r)            No Material Actions or Proceedings.  Except as set forth in the Registration Statement, the Time of Sale Prospectus and the Prospectus, there is not pending or, to the knowledge of the Company, threatened or contemplated, any action, suit or proceeding to which the Company or its subsidiaries is a party or of which any property or assets of the Company or its subsidiaries is the subject before or by any court or governmental agency, authority or body, or any arbitrator, which, individually or in the aggregate, might result in any Material Adverse Effect.

(s)            Intellectual Property Rights. The Company and its subsidiaries own, possess, or can acquire on reasonable terms ownership of or a license to, all Intellectual Property necessary for the conduct of the Company’s business as now conducted or as described in the Registration Statement, the Time of Sale Prospectus and the Prospectus to be conducted, except as such failure to own, possess, or acquire such rights would not result in a Material Adverse Effect.  Furthermore, (A) to the knowledge of the Company, there is no infringement, misappropriation or violation  by third parties of any such Intellectual Property, except as such infringement, misappropriation or violation would not result in a Material Adverse Effect; (B) there is no pending or, to the knowledge of the Company, threatened, action, suit, proceeding or claim by others challenging the Company’s or its subsidiaries’ rights in or to any such Intellectual Property, and the Company is unaware of any facts which would form a reasonable basis for any such claim; (C) the Intellectual Property owned by the Company and its subsidiaries, and to the knowledge of the Company, the Intellectual Property licensed to the Company or its subsidiaries, has not been adjudged invalid or unenforceable, in whole or in part, and there is no pending or, to the knowledge of the Company, 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 would form a reasonable basis for any such claim; (D) there is no pending or, to the knowledge of the Company, threatened action, suit, proceeding or claim by others that the Company or its subsidiaries infringe, misappropriate or otherwise violate any Intellectual Property or other proprietary rights of others, the Company has not received any written notice of such claim and the Company is unaware of any other fact which would form a reasonable basis for any such claim; and (E) to the knowledge of the Company, no employee of the Company or its subsidiaries is in or has ever been in violation of any term of any employment contract, patent disclosure agreement, invention assignment agreement, non-competition agreement, non-solicitation agreement, nondisclosure agreement or any restrictive covenant to or with a former employer where the basis of such violation relates to such employee’s employment with the Company or its subsidiaries or actions undertaken by the employee while employed with the Company or its subsidiaries, except as such violation would not result in a Material Adverse Effect.  “Intellectual Property” shall mean all patents, patent applications, trade and service marks, trade and service  mark registrations, trade names, copyrights, licenses, inventions, trade secrets, domain names, technology, know-how and other intellectual property.

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(t)            All Necessary Permits, etc.  The Company and its subsidiaries hold, and are operating in compliance in all material respects with, all franchises, grants, authorizations, licenses, permits, easements, consents, certificates and orders of any governmental or self-regulatory body required for the conduct of their respective businesses and all such franchises, grants, authorizations, licenses, permits, easements, consents, certifications and orders are valid and in full force and effect; and neither the Company nor any of its subsidiaries have received notice of any revocation or modification of any such franchise, grant, authorization, license, permit, easement, consent, certification or order or has reason to believe that any such franchise, grant, authorization, license, permit, easement, consent, certification or order will not be renewed in the ordinary course; and the Company and its subsidiaries are in compliance in all material respects with all applicable federal, state, local and foreign laws, regulations, orders and decrees.

(u)           Title to Properties.  The Company and its subsidiaries have good and marketable title to all property (whether real or personal) described in the Registration Statement, the Time of Sale Prospectus and the Prospectus as being owned by them, in each case free and clear of all liens, claims, security interests, other encumbrances or defects except such as are described in the Registration Statement, the Time of Sale Prospectus and the Prospectus.  The property held under lease by the Company or its subsidiaries is held by them under valid, subsisting and enforceable leases with only such exceptions with respect to any particular lease as do not interfere in any material respect with the conduct of the business of the Company or its subsidiaries.

(v)           Tax Law Compliance. The Company and its subsidiaries have timely filed all federal, state, local and foreign income and franchise tax returns required to be filed and are not in default in the payment of any taxes which were payable pursuant to said returns or any assessments with respect thereto, other than any which the Company or its subsidiaries are contesting in good faith.  There is no pending dispute with any taxing authority relating to any of such returns, and the Company has no knowledge of any proposed liability for any tax to be imposed upon the properties or assets of the Company or its subsidiaries for which there is not an adequate reserve reflected in the Company’s financial statements included in the Registration Statement.

(w)          Insurance.  Each of the Company and its subsidiaries carry, or are covered by, insurance in such amounts and covering such risks as is adequate for the conduct of their respective businesses and the value of their properties and as is customary for companies engaged in similar businesses in similar industries; all policies of insurance and any fidelity or surety bonds insuring the Company, its subsidiaries, or their business, assets, employees, officers and directors are in full force and effect; the Company and its subsidiaries is in compliance with the terms of such policies and instruments in all material respects; there are no claims by the Company or its subsidiaries under any such policy or instrument as to which any insurance company is denying liability or defending under a reservation of rights clause; the Company and its subsidiaries have not been refused any insurance coverage sought or applied for; and the Company and its subsidiaries have no reason to believe that they will not be able to renew their existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business at a cost that would not have a Material Adverse Effect.

(x)           Compliance with Environmental Laws.  The Company and its subsidiaries (A) are in compliance with any and all applicable federal, state, local and foreign laws, rules, regulations, decisions and orders relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (collectively, “Environmental Laws”); (B) have received and are in compliance with all permits, licenses or

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other approvals required of it under applicable Environmental Laws to conduct its business; and (C) have not received notice of any actual or potential liability for the investigation or remediation of any disposal or release of hazardous or toxic substances or wastes, pollutants or contaminants, except in any such case for any such failure to comply, or failure to receive required permits, licenses or approvals, or liability as would not, individually or in the aggregate, result in a Material Adverse Effect.

(y)           ERISA Compliance.  Each employee benefit plan, within the meaning of Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), that is maintained, administered or contributed to by the Company or any of its affiliates for employees or former employees of the Company and its affiliates has been maintained in compliance in all material respects 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”).  No prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred with respect to any such plan, excluding transactions effected pursuant to a statutory or administrative exemption; and for each such plan that is subject to the funding rules of Section 412 of the Code or Section 302 of ERISA, no “Accumulated funding deficiency,” as defined in Section 412 of the Code, has been incurred, whether or not waived, and the fair market value of the assets of each such plan (excluding for these purposes accrued but unpaid contributions) exceeds the present value of all benefits accrued under such plan determined using reasonable actuarial assumptions.

(z)           Company Not an “Investment Company”.  The Company is not and, after giving effect to the offering and sale of the Shares, will not be an “investment company,” or an entity “controlled” by and “investment company” as such terms are defined in the Investment Company Act of 1940, as amended.

(aa)         No Price Stabilization or Manipulation; Compliance with Regulation M.  Neither the Company nor any of its subsidiaries has taken, directly or indirectly, any action designed to or that might cause or result in stabilization or manipulation of the price of the Shares or of any “reference security” (as defined in Rule 100 of Regulation M under the Exchange Act (“Regulation M”)) with respect to the Shares, whether to facilitate the sale or resale of the Offered Shares or otherwise, and has taken no action which would directly or indirectly violate Regulation M.

(bb)         Related-Party Transactions.  There are no business relationships or related-party transactions involving the Company or any of its subsidiaries or any other person required to be described in the Registration Statement, the Time of Sale Prospectus or the Prospectus that have not been described as required.

(cc)         Exchange Act Compliance.  The documents incorporated or deemed to be incorporated by reference in the Prospectus (the “Incorporated Documents”), when they became effective or were filed with the Commission, as the case may be, conformed in all material respects to the requirements of the Securities Act or the Exchange Act, as applicable, and were filed on a timely basis with the Commission and none of such documents contained an 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; any further Incorporated Documents, when filed with the Commission, will conform in all material respects to the requirements of the Exchange Act, and will not contain an 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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(dd)         Sarbanes-Oxley.  The Company is in compliance with all applicable provisions of the Sarbanes-Oxley Act and the rules and regulations of the Commission thereunder.

(ee)         FINRA Matters.  All of the information provided to the Underwriters or to counsel for the Underwriters by the Company and, to the knowledge of the Company, by its counsel, its officers and directors and the holders of any securities (debt or equity) or options to acquire any securities of the Company  in connection with the offering of the Offered Shares is true, complete, correct and compliant with FINRA’s rules, and any letters, filings or other supplemental information provided to FINRA by the Company pursuant to FINRA Rules or NASD Conduct Rules is true, complete and correct.

(ff)          Parties to Lock-up Agreements.  The Company has furnished to the Underwriters a letter agreement in the form attached hereto as Exhibit D (the “Lock-up Agreement”) from each of the persons listed on Exhibit E. Such Exhibit E lists under an appropriate caption the directors and officers of the Company.  If any additional persons shall become directors or officers of the Company prior to the end of the Company Lock-up Period (as defined below), the Company shall cause each such person, prior to or contemporaneously with their appointment or election as a director or officer of the Company, to execute and deliver to the Representatives a Lock-up Agreement.

(gg)         Statistical and Market-Related Data.  All statistical, demographic and market-related data included in the Registration Statement, the Time of Sale Prospectus or the Prospectus are based on or derived from sources that the Company believes, after reasonable inquiry, to be reliable and accurate. To the extent required, the Company has obtained the written consent to the use of such data from such sources.

(hh)         No Unlawful Contributions or Other Payments.  Neither the Company nor any of its subsidiaries nor, to the best of the Company’s knowledge, any employee or agent of the Company or any subsidiary, has made any contribution or other payment to any official of, or candidate for, any federal, state or foreign office in violation of any law or of the character required to be disclosed in the Registration Statement, the Time of Sale Prospectus or the Prospectus.

(ii)           Foreign Corrupt Practices Act.  Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, representative, employee or affiliate of the Company or any of its subsidiaries, is aware of or has taken any action directly or indirectly, that would result in a violation by such persons of the FCPA (as defined below), including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “Foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA, and the Company and its subsidiaries have conducted their respective businesses in compliance with the FCPA and have instituted and maintain policies and procedures designed to ensure, and which are reasonably expected to continue to ensure, continued compliance therewith.  “FCPA” means the Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder.

(jj)           Money Laundering Laws.  The operations of the Company and its subsidiaries have complied in all material respects with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the

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money laundering statutes of all jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”), and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

(kk)         OFAC.  Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer or employee of the Company or any of its subsidiaries is currently subject to any U.S. sanctions administered by the Office of Foreign Assets Control of the U.S. Department of the Treasury.

(ll)           Brokers.  Other than as contemplated by this Agreement, the Company has not incurred any liability for any finder’s or broker’s fee or representative’s commission in connection with the execution and delivery of this Agreement or the consummation of the transactions contemplated hereby or thereby.

(mm)      Occupational Laws.  The Company and its subsidiaries (A) are in compliance, in all material respects, with any and all applicable foreign, federal, state and local laws, rules, regulations, treaties, statutes and codes promulgated by any and all governmental authorities (including pursuant to the Occupational Health and Safety Act) relating to the protection of human health and safety in the workplace (“Occupational Laws”); (B) have received all material permits, licenses or other approvals required of it under applicable Occupational Laws to conduct its business as currently conducted; and (C) are in compliance, in all material respects, with all terms and conditions of such permit, license or approval.  No action, proceeding, revocation proceeding, writ, injunction or claim is pending or, to the Company’s knowledge, threatened against the Company or any of its subsidiaries relating to Occupational Laws, and the Company does not have knowledge of any facts, circumstances or developments relating to its operations or cost accounting practices that could reasonably be expected to form the basis for or give rise to such actions, suits, investigations or proceedings.

(nn)         Compliance with Applicable Laws.  Except as described in the Registration Statement, the Time of Sale Prospectus and the Prospectus, the Company and its subsidiaries: (A) are and at all times have been in full compliance with all statutes, rules, regulations, or guidances, including, without limitation, the Federal Food, Drug and Cosmetic Act and implementing regulations at 21 C.F.R. Parts 50, 54, 56, 58 and 812, applicable to Company and its subsidiaries to the ownership, testing, development, manufacture, packaging, processing, use, distribution, marketing, labeling, promotion, sale, offer for sale, storage, import, export or disposal of any product manufactured or distributed by the Company (“Applicable Laws”), except as could not, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect; (B) have not received any FDA Form 483, notice of adverse finding, warning letter, untitled letter or other correspondence or notice from any other federal, state, local or foreign governmental or regulatory authority (each, a “Governmental Authority”) alleging or asserting noncompliance with any Applicable Laws or any licenses, certificates, approvals, clearances, authorizations, permits and supplements or amendments thereto required by any such Applicable Laws (“Authorizations”); (C) possess all material Authorizations and such Authorizations are valid and in full force and effect and are not in violation of any term of any such Authorizations; (D) have  not received notice of any claim, action, suit, proceeding, hearing, enforcement, investigation, arbitration or other action from any Governmental Authority or third party alleging that any product operation or activity is in violation of any Applicable Laws or Authorizations and has no knowledge that any such Governmental Authority or third party intends to assert any

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such claim, litigation, arbitration, action, suit, investigation or proceeding; (E) have  not received notice that any Governmental Authority has taken, is taking or intends to take action to limit, suspend, modify or revoke any Authorizations and the Company has no knowledge that any such Governmental Authority is considering such action; and (F) have 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 complete and correct in all material respects on the date filed (or were corrected or supplemented by a subsequent submission).

(oo)         Clinical Studies.  The studies, tests and preclinical and clinical trials conducted by or on behalf of the Company or any of its subsidiaries with respect to programs that are currently in development or in discovery or are described in the Registration Statement, the Time of Sale Prospectus or the Prospectus, were and, if still pending, are, in all material respects, being conducted in accordance with applicable experimental protocols, procedures and controls pursuant to accepted professional scientific standards and all relevant Applicable Laws and Authorizations; the descriptions of the results of such studies, tests and trials contained in the Registration Statement and the Prospectus are accurate and complete in all material respects and fairly present the data derived from such studies, tests and trials; except to the extent disclosed in the Registration Statement and the Prospectus, the Company is not aware of any studies, tests or trials the results of which the Company believes reasonably call into question the study, test, or trial results described or referred to in the Registration Statement and the Prospectus when viewed in the context in which such results are described and the clinical state of development; and neither the Company nor any of its subsidiaries have received any notices or correspondence from any Governmental Authority requiring the termination, suspension or material modification of any studies, tests or preclinical or clinical trials conducted by or on behalf of the Company.

(pp)         No Contract Terminations.  Neither the Company nor any of its subsidiaries has sent or received any communication regarding termination of, or intent not to renew, any of the contracts or agreements referred to or described in any preliminary prospectus, the Prospectus or any free writing prospectus, or referred to or described in, or filed as an exhibit to, the Registration Statement, or any document incorporated by reference therein, and no such termination or non-renewal has been threatened by the Company or any of its subsidiaries or, to the Company’s knowledge, any other party to any such contract or agreement, which threat of termination or non-renewal has not been rescinded as of the date hereof or which termination or non-renewal would not be reasonably likely to result in a Material Adverse Effect.

(qq)         Dividend Restrictions.  No subsidiary of the Company is prohibited or restricted, directly or indirectly, from paying dividends to the Company, or from making any other distribution with respect to such subsidiary’s equity securities or from repaying to the Company or any other subsidiary of the Company any amounts that may from time to time become due under any loans or advances to such subsidiary from the Company or from transferring any property or assets to the Company or to any other subsidiary.

Any certificate signed by any officer of the Company or any of its subsidiaries and delivered to any Underwriter or to counsel for the Underwriters in connection with the offering, or the purchase and sale, of the Offered Shares shall be deemed a representation and warranty by the Company to each Underwriter as to the matters covered thereby.

The Company has a reasonable basis for making each of the representations set forth in this Section 1.  The Company acknowledges that the Underwriters and, for purposes of

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the opinions to be delivered pursuant to Section 6 hereof, counsel to the Company and counsel to the Underwriters, will rely upon the accuracy and truthfulness of the foregoing representations and hereby consents to such reliance.

Section 2.              Purchase, Sale and Delivery of the Offered Shares.

(a)           The Firm Shares.  Upon the terms herein set forth, the Company agrees to issue and sell to the several Underwriters an aggregate of 18,000,000 Firm Shares.  On the basis of the representations, warranties and agreements herein contained, and upon the terms but subject to the conditions herein set forth, the Underwriters agree, severally and not jointly, to purchase from the Company the respective number of Firm Shares set forth opposite their names on Schedule A.  The purchase price per Firm Share to be paid by the several Underwriters to the Company shall be $3.431 per share.

(b)           The First Closing Date.  Delivery of certificates for the Firm Shares to be purchased by the Underwriters and payment therefor shall be made at the offices of Latham & Watkins LLP, 650 Town Center Drive, 20th Floor, Costa Mesa, California 92626 (or such other place as may be agreed to by the Company and the Representatives) at 9:00 a.m. New York time, on November 15, 2012, or such other time and date not later than 1:30 p.m. New York time, on November 15, 2012, as the Representatives shall designate by notice to the Company (the time and date of such closing are called the “First Closing Date”).  The Company hereby acknowledges that circumstances under which the Representatives may provide notice to postpone the First Closing Date as originally scheduled include, but are not limited to, any determination by the Company or the Representatives to recirculate to the public copies of an amended or supplemented Prospectus or a delay as contemplated by the provisions of Section 11.

(c)           The Optional Shares; Option Closing Date.  In addition, on the basis of the representations, warranties and agreements herein contained, and upon the terms but subject to the conditions herein set forth, the Company hereby grants an option to the several Underwriters to purchase, severally and not jointly, up to an aggregate of 2,700,000 Optional Shares from the Company at the purchase price per share to be paid by the Underwriters for the Firm Shares, less an amount per share equal to any dividend or distribution declared by the Company and payable on the Firm Shares but not payable on Optional Shares.  The option granted hereunder is for use by the Underwriters solely in covering any over-allotments in connection with the sale and distribution of the Firm Shares.  The option granted hereunder may be exercised at any time and from time to time in whole or in part upon notice by the Representatives to the Company, which notice may be given at any time within 30 days from the date of this Agreement.  Such notice shall set forth (i) the aggregate number of Optional Shares as to which the Underwriters are exercising the option and (ii) the time, date and place at which certificates for the Optional Shares will be delivered (which time and date may be simultaneous with, but not earlier than, the First Closing Date; and in the event that such time and date are simultaneous with the First Closing Date, the term “First Closing Date” shall refer to the time and date of delivery of certificates for the Firm Shares and such Optional Shares).  Any such time and date of delivery, if subsequent to the First Closing Date, is called an “Option Closing Date,” shall be determined by the Representatives and shall not be earlier than three nor later than five full business days after delivery of such notice of exercise.  If any Optional Shares are to be purchased, each Underwriter agrees, severally and not jointly, to purchase the number of Optional Shares (subject to such adjustments to eliminate fractional shares as the Representatives may determine) that bears the same proportion to the total number of Optional Shares to be purchased as the number of Firm Shares set forth on Schedule A opposite the name of such Underwriter

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bears to the total number of Firm Shares.  The Representatives may cancel the option at any time prior to its expiration by giving written notice of such cancellation to the Company.

(d)           Public Offering of the Offered Shares.  The Representatives hereby advise the Company that the Underwriters intend to offer for sale to the public, initially on the terms set forth in the Registration Statement, the Time of Sale Prospectus and the Prospectus, their respective portions of the Offered Shares as soon after this Agreement has been executed as the Representatives, in their sole judgment, have determined is advisable and practicable.

(e)           Payment for the Offered Shares.  Payment for the Offered Shares shall be made at the First Closing Date (and, if applicable, at each Option Closing Date) by wire transfer of immediately available funds to the order of the Company.

It is understood that the Representatives have been authorized, for their own accounts and the accounts of the several Underwriters, to accept delivery of and receipt for, and make payment of the purchase price for, the Firm Shares and any Optional Shares the Underwriters have agreed to purchase.  Each of Jefferies and J.P. Morgan, individually and not as the Representatives of the Underwriters, may (but shall not be obligated to) make payment for any Offered Shares to be purchased by any Underwriter whose funds shall not have been received by the Representatives by the First Closing Date or the applicable Option Closing Date, as the case may be, for the account of such Underwriter, but any such payment shall not relieve such Underwriter from any of its obligations under this Agreement.

(f)            Delivery of the Offered Shares.  The Company shall deliver, or cause to be delivered to the Representatives for the accounts of the several Underwriters, the Firm Shares at the First Closing Date, against release of a wire transfer of immediately available funds for the amount of the purchase price therefor.  The Company shall also deliver, or cause to be delivered to the Representatives for the accounts of the several Underwriters, the Optional Shares the Underwriters have agreed to purchase at the First Closing Date or the applicable Option Closing Date, as the case may be, against the release of a wire transfer of immediately available funds for the amount of the purchase price therefor.  The Offered Shares shall be credited to the accounts of or registered in such names and denominations as the Representatives shall have requested at least two full business days prior to the First Closing Date (or the applicable Option Closing Date, as the case may be).  The certificates for the Offered Shares, if any, shall be made available for inspection on the business day preceding the First Closing Date (or the applicable Option Closing Date, as the case may be) at a location in New York City as the Representatives may designate.  Time shall be of the essence, and delivery at the time and place specified in this Agreement is a further condition to the obligations of the Underwriters.

Section 3.              Additional Covenants.  The Company further covenants and agrees with each Underwriter as follows:

(a)           Delivery of Registration Statement, Time of Sale Prospectus and Prospectus.  The Company shall furnish to you in New York City, without charge, prior to 10:00 a.m. New York City time on the business day next succeeding the date of this Agreement and during the period when a prospectus relating to the Offered Shares is required by the Securities Act to be delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule) in connection with sales of the Offered Shares, as many copies of the Time of Sale Prospectus, the Prospectus and any supplements and amendments thereto or to the Registration Statement as you may reasonably request.

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(b)           Representatives’ Review of Proposed Amendments and Supplements.  During the period when a prospectus relating to the Offered Shares is required by the Securities Act to be delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule), the Company (i) will furnish to the Representatives for review, a reasonable period of time prior to the proposed time of filing of any proposed amendment or supplement to the Registration Statement, a copy of each such amendment or supplement and (ii) will not amend or supplement the Registration Statement (including any amendment or supplement through incorporation of any report filed under the Exchange Act) without the Representatives’ prior written consent. Prior to amending or supplementing any preliminary prospectus, the Time of Sale Prospectus or the Prospectus (including any amendment or supplement through incorporation of any report filed under the Exchange Act), the Company shall furnish to the Representatives for review, a reasonable amount of time prior to the time of filing or use of the proposed amendment or supplement, a copy of each such proposed amendment or supplement. The Company shall not file or use any such proposed amendment or supplement without the Representatives’ prior written consent. The Company shall file with the Commission within the applicable period specified in Rule 424(b) under the Securities Act any prospectus required to be filed pursuant to such Rule.

(c)           Free Writing Prospectuses.  The Company shall furnish to the Representatives for review, a reasonable amount of time prior to the proposed time of filing or use thereof, a copy of each proposed free writing prospectus or any amendment or supplement thereto prepared by or on behalf of, used by, or referred to by the Company, and the Company shall not file, use or refer to any proposed free writing prospectus or any amendment or supplement thereto without the Representatives’ prior written consent.  The Company shall furnish to each Underwriter, without charge, as many copies of any free writing prospectus prepared by or on behalf of, used by or referred to by the Company as such Underwriter may reasonably request.  If at any time when a prospectus is required by the Securities Act to be delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule) in connection with sales of the Offered Shares (but in any event if at any time through and including the First Closing Date) there occurred or occurs an event or development as a result of which any free writing prospectus prepared by or on behalf of, used by, or referred to by the Company conflicted or would conflict with the information contained in the Registration Statement or included or would include an untrue statement of a material fact or omitted or would omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances prevailing at such time, not misleading, the Company shall promptly amend or supplement such free writing prospectus to eliminate or correct such conflict so that the statements in such free writing prospectus as so amended or supplemented will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances prevailing at such time, not misleading, as the case may be; provided, however, that prior to amending or supplementing any such free writing prospectus, the Company shall furnish to the Representatives for review, a reasonable amount of time prior to the proposed time of filing or use thereof, a copy of such proposed amended or supplemented free writing prospectus and the Company shall not file, use or refer to any such amended or supplemented free writing prospectus without the Representatives’ prior written consent.

(d)           Filing of Underwriter Free Writing Prospectuses.  The Company shall not take any action that would result in an Underwriter or the Company being required to file with the Commission pursuant to Rule 433(d) under the Securities Act a free writing prospectus prepared by or on behalf of such Underwriter that such Underwriter otherwise would not have been required to file thereunder.

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(e)           Amendments and Supplements to Time of Sale Prospectus.  If the Time of Sale Prospectus is being used to solicit offers to buy the Offered Shares at a time when the Prospectus is not yet available to prospective purchasers, and any event shall occur or condition exist as a result of which it is necessary to amend or supplement the Time of Sale Prospectus so that the Time of Sale Prospectus does not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances when delivered to a prospective purchaser, not misleading, or if any event shall occur or condition exist as a result of which the Time of Sale Prospectus conflicts with the information contained in the Registration Statement, or if, in the opinion of counsel for the Underwriters, it is necessary to amend or supplement the Time of Sale Prospectus to comply with applicable law, the Company shall (subject to Section 3(b) and Section 3(c) hereof) promptly prepare, file with the Commission and furnish, at its own expense, to the Underwriters and to any dealer upon request, either amendments or supplements to the Time of Sale Prospectus so that the statements in the Time of Sale Prospectus as so amended or supplemented will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances when delivered to a prospective purchaser, not misleading or so that the Time of Sale Prospectus, as amended or supplemented, will no longer conflict with the information contained in the Registration Statement, or so that the Time of Sale Prospectus, as amended or supplemented, will comply with applicable law.

(f)            Certain Notifications and Required Actions.  After the date of this Agreement, the Company shall promptly advise the Representatives in writing of: (i) the receipt of any comments of, or requests for additional or supplemental information from, the Commission; (ii) the time and date of any filing of any post-effective amendment to the Registration Statement or any amendment or supplement to any preliminary prospectus, the Time of Sale Prospectus, any free writing prospectus or the Prospectus; (iii) the time and date that any post-effective amendment to the Registration Statement becomes effective; and (iv) the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or any post-effective amendment thereto or any amendment or supplement to any preliminary prospectus, the Time of Sale Prospectus or the Prospectus or of any order preventing or suspending the use of any preliminary prospectus, the Time of Sale Prospectus, any free writing prospectus or the Prospectus, or of any proceedings to remove, suspend or terminate from listing or quotation the Shares from any securities exchange upon which they are listed for trading or included or designated for quotation, or of the threatening or initiation of any proceedings for any of such purposes.  If the Commission shall enter any such stop order at any time, the Company will use its best efforts to obtain the lifting of such order at the earliest possible moment.  Additionally, the Company agrees that it shall comply with all applicable provisions of Rule 424(b), Rule 433 and Rule 430B under the Securities Act and will use its reasonable efforts to confirm that any filings made by the Company under Rule 424(b) or Rule 433 were received in a timely manner by the Commission.

(g)           Amendments and Supplements to the Prospectus and Other Securities Act Matters.  If any event shall occur or condition exist as a result of which it is necessary to amend or supplement the Prospectus so that the Prospectus does not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances when the Prospectus is delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule) to a purchaser, not misleading, or if in the opinion of the Representatives or counsel for the Underwriters it is otherwise necessary to amend or supplement the Prospectus to comply with applicable law, the Company agrees (subject to Section 3(b) and 3(c) hereof) to promptly prepare, file with the Commission and furnish, at its own expense, to the Underwriters and to any dealer upon request,

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amendments or supplements to the Prospectus so that the statements in the Prospectus as so amended or supplemented will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances when the Prospectus is delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule)to a purchaser, not misleading or so that the Prospectus, as amended or supplemented, will comply with applicable law.  Neither the Representatives’ consent to, nor delivery of, any such amendment or supplement shall constitute a waiver of any of the Company’s obligations under Section 3(b) or Section 3(c).

(h)           Blue Sky Compliance.  The Company shall cooperate with the Representatives and counsel for the Underwriters to qualify or register the Offered Shares for sale under (or obtain exemptions from the application of) the state securities or blue sky laws or Canadian provincial securities laws (or other foreign laws) of those jurisdictions designated by the Representatives, shall comply with such laws and shall continue such qualifications, registrations and exemptions in effect so long as required for the distribution of the Offered Shares.  The Company shall not be required to qualify as a foreign corporation or to take any action that would subject it to general service of process in any such jurisdiction where it is not presently qualified or where it would be subject to taxation as a foreign corporation.  The Company will advise the Representatives promptly of the suspension of the qualification or registration of (or any such exemption relating to) the Offered Shares for offering, sale or trading in any jurisdiction or any initiation or threat of any proceeding for any such purpose, and in the event of the issuance of any order suspending such qualification, registration or exemption, the Company shall use its best efforts to obtain the withdrawal thereof at the earliest possible moment.

(i)            Use of Proceeds.  The Company shall apply the net proceeds from the sale of the Offered Shares sold by it in the manner described under the caption “Use of Proceeds” in the Registration Statement, the Time of Sale Prospectus and the Prospectus.

(j)            Transfer Agent.  The Company shall engage and maintain, at its expense, a registrar and transfer agent for the Shares.

(k)           Earnings Statement.  The Company will make generally available to its security holders and to the Representatives as soon as practicable an earnings statement (which need not be audited) covering a period of at least twelve months beginning with the first fiscal quarter of the Company commencing after the date of this Agreement that will satisfy the provisions of Section 11(a) of the Securities Act and the rules and regulations of the Commission thereunder.

(l)            Continued Compliance with Securities Laws.  The Company will comply with the Securities Act and the Exchange Act so as to permit the completion of the distribution of the Offered Shares as contemplated by this Agreement, the Registration Statement, the Time of Sale Prospectus and the Prospectus.  Without limiting the generality of the foregoing, the Company will, during the period when a prospectus relating to the Offered Shares is required by the Securities Act to be delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule), file on a timely basis with the Commission and the NASDAQ all reports and documents required to be filed under the Exchange Act.

(m)          Listing.  The Company will use its best efforts to list, subject to notice of issuance, the Offered Shares on the NASDAQ.

(n)           Company to Provide Copy of the Prospectus in Form That May be Downloaded from the Internet.  If requested by the Representatives, the Company shall cause to be prepared

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and delivered, at its expense, within one business day from the effective date of this Agreement, to the Representatives an “electronic Prospectus” to be used by the Underwriters in connection with the offering and sale of the Offered Shares.  As used herein, the term “electronic Prospectus” means a form of Time of Sale Prospectus, and any amendment or supplement thereto, that meets each of the following conditions: (i) it shall be encoded in an electronic format, satisfactory to the Representatives, that may be transmitted electronically by the Representatives and the other Underwriters to offerees and purchasers of the Offered Shares; (ii) it shall disclose the same information as the paper Time of Sale Prospectus, except to the extent that graphic and image material cannot be disseminated electronically, in which case such graphic and image material shall be replaced in the electronic Prospectus with a fair and accurate narrative description or tabular representation of such material, as appropriate; and (iii) it shall be in or convertible into a paper format or an electronic format, satisfactory to the Representatives, that will allow investors to store and have continuously ready access to the Time of Sale Prospectus at any future time, without charge to investors (other than any fee charged for subscription to the Internet as a whole and for on-line time).  The Company hereby confirms that it has included or will include in the Prospectus filed pursuant to EDGAR or otherwise with the Commission and in the Registration Statement at the time it was declared effective an undertaking that, upon receipt of a request by an investor or his or her representative, the Company shall transmit or cause to be transmitted promptly, without charge, a paper copy of the Time of Sale Prospectus.

(o)           Agreement Not to Offer or Sell Additional Shares.  During the period commencing on and including the date hereof and continuing through and including the 90th day following the date of the Prospectus (such period, as extended as described below, being referred to herein as the “Lock-up Period”), the Company will not, without the prior written consent of Jefferies and J.P. Morgan (which consent may be withheld in their sole discretion), directly or indirectly: (i) sell, offer to sell, contract to sell or lend any Shares or Related Securities (as defined below); (ii) effect any short sale, or establish or increase any “put equivalent position” (as defined in Rule 16a-1(h) under the Exchange Act) or liquidate or decrease any “call equivalent position” (as defined in Rule 16a-1(b) under the Exchange Act) of any Shares or Related Securities; (iii) pledge, hypothecate or grant any security interest in; (iv) in any other way transfer or dispose of any Shares or Related Securities; (v) enter into any swap, hedge or similar arrangement or agreement that transfers, in whole or in part, the economic risk of ownership of any Shares or Related Securities, regardless of whether any such transaction is to be settled in securities, in cash or otherwise; (vi) announce the offering of any Shares or Related Securities; (vii) file any registration statement under the Securities Act in respect of any Shares or Related Securities (other than as contemplated by this Agreement with respect to the Offered Shares); or (viii) publicly announce the intention to do any of the foregoing; provided, however, that the Company may (A) effect the transactions contemplated hereby and (B) issue Shares or options to purchase Shares, or issue Shares upon exercise of options, pursuant to any stock option plan, stock bonus or other stock plan or arrangement described in the Registration Statement, the Time of Sale Prospectus and the Prospectus.  For purposes of the foregoing, “Related Securities” shall mean any options or warrants or other rights to acquire Shares or any securities exchangeable or exercisable for or convertible into Shares, or to acquire other securities or rights ultimately exchangeable or exercisable for, or convertible into, Shares.  If (i) during the last 17 days of the 90-day initial lock-up period, the Company issues an earnings release or discloses material news or a material event relating to the Company occurs, or (ii) prior to the expiration of such period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of such period, then in each case the Lock-up Period will be extended until the expiration of the 18-day period beginning on the date of the issuance of the earnings release or the disclosure of the material news or occurrence of the material event, as applicable, unless

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Jefferies and J.P. Morgan waive, in writing, such extension (which waiver may be withheld in their sole discretion).  The Company will provide Jefferies and J.P. Morgan with prior notice of any such announcement that gives rise to an extension of the Lock-up Period.

(p)           Future Reports to the Representatives.  During the period of five years hereafter, the Company will furnish to the Representatives, c/o Jefferies, at 520 Madison Avenue, New York, New York 10022, Attention: Global Head of Syndicate: (i) as soon as practicable after the end of each fiscal year, copies of the Annual Report of the Company containing the balance sheet of the Company as of the close of such fiscal year and statements of income, stockholders’ equity and cash flows for the year then ended and the opinion thereon of the Company’s independent public or certified public accountants; (ii) as soon as practicable after the filing thereof, copies of each proxy statement, Annual Report on Form 10-K, Quarterly Report on Form 10-Q, Current Report on Form 8-K or other report filed by the Company with the Commission or any securities exchange; and (iii) as soon as available, copies of any report or communication of the Company furnished or made available generally to holders of its capital stock; provided, however, that the requirements of this Section 3(p) shall be satisfied to the extent that such reports, statement, communications, financial statements or other documents are available on EDGAR.

(q)           Investment Limitation.  The Company shall not invest or otherwise use the proceeds received by the Company from its sale of the Offered Shares in such a manner as would require the Company or any of its subsidiaries to register as an investment company under the Investment Company Act.

(r)            No Stabilization or Manipulation; Compliance with Regulation M.  The Company will not take, directly or indirectly, any action designed to or that might cause or result in stabilization or manipulation of the price of the Shares or any reference security with respect to the Shares, whether to facilitate the sale or resale of the Offered Shares or otherwise, and the Company will, and shall cause each of its affiliates to, comply with all applicable provisions of Regulation M.

(s)            Enforce Lock-up Agreements.  During the Lock-up Period, the Company will enforce all agreements between the Company and any of its security holders that restrict or prohibit, expressly or in operation, the offer, sale or transfer of Shares or Related Securities or any of the other actions restricted or prohibited under the terms of the form of Lock-up Agreement.  In addition, the Company will direct the transfer agent to place stop transfer restrictions upon any such securities of the Company that are bound by such “lock-up” agreements for the duration of the periods contemplated in such agreements, including, without limitation, “lock-up” agreements entered into by the Company’s officers and directors pursuant to Section 6(j) hereof.

(t)            Company to Provide Interim Financial Statements.  Prior to the Closing Date, the Company will furnish the Underwriters, as soon as they have been prepared by or are available to the Company, a copy of any unaudited interim financial statements of the Company for any period subsequent to the period covered by the most recent financial statements appearing in the Registration Statement and the Prospectus.

The Representatives, on behalf of the several Underwriters, may, in their sole discretion, waive in writing the performance by the Company of any one or more of the foregoing covenants or extend the time for their performance.

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Section 4.                                          Payment of Expenses.  The Company agrees to pay all costs, fees and expenses incurred in connection with the performance of its obligations hereunder and in connection with the transactions contemplated hereby, including without limitation (i) all expenses incident to the issuance and delivery of the Offered Shares (including all printing and engraving costs), (ii) all fees and expenses of the registrar and transfer agent of the Shares, (iii) all necessary issue, transfer and other stamp taxes in connection with the issuance and sale of the Offered Shares to the Underwriters, (iv) all fees and expenses of the Company’s counsel, independent public or certified public accountants and other advisors, (v) all costs and expenses incurred in connection with the preparation, printing, filing, shipping and distribution of the Registration Statement (including financial statements, exhibits, schedules, consents and certificates of experts), the Time of Sale Prospectus, the Prospectus, each free writing prospectus prepared by or on behalf of, used by, or referred to by the Company, and each preliminary prospectus, and all amendments and supplements thereto, and this Agreement, (vi) all filing fees, attorneys’ fees and expenses incurred by the Company or the Underwriters in connection with qualifying or registering (or obtaining exemptions from the qualification or registration of) all or any part of the Offered Shares for offer and sale under the state securities or blue sky laws or the provincial securities laws of Canada, and, if requested by the Representatives, preparing and printing a “Blue Sky Survey” or memorandum and a “Canadian wrapper”, and any supplements thereto, advising the Underwriters of such qualifications, registrations and exemptions, (vii) the costs, fees and expenses incurred by the Underwriters in connection with determining their compliance with the rules and regulations of FINRA related to the Underwriters’ participation in the offering and distribution of the Offered Shares, including any related filing fees and the legal fees of, and disbursements by, counsel to the Underwriters, (viii) the costs and expenses of the Company relating to investor presentations on any “road show” undertaken in connection with the offering of the Offered Shares, including, without limitation, expenses associated with the preparation or dissemination of any electronic road show, expenses associated with the production of road show slides and graphics, fees and expenses of any consultants engaged in connection with the road show presentations with the prior approval of the Company, travel and lodging expenses of the representatives, employees and officers of the Company and any such consultants, and the cost of any aircraft chartered in connection with the road show, (ix) the fees and expenses associated with listing the Shares on the NASDAQ, and (x) all other fees, costs and expenses of the nature referred to in Item 14 of Part II of the Registration Statement.  Except as provided in this Section 4 or in Section 7, Section 9 or Section 10 hereof, the Underwriters shall pay their own expenses, including the fees and disbursements of their counsel.

Section 5.                                          Covenant of the Underwriters.  Each Underwriter severally and not jointly covenants with the Company not to take any action without the Company’s prior written consent that would result in the Company being required to file with the Commission pursuant to Rule 433(d) under the Securities Act a free writing prospectus prepared by or on behalf of such Underwriter that otherwise would not, but for such actions, be required to be filed by the Company under Rule 433(d).

Section 6.                                          Conditions of the Obligations of the Underwriters.  The obligations of the several Underwriters to purchase and pay for the Offered Shares as provided herein on the First Closing Date and, with respect to the Optional Shares, each Option Closing Date, shall be subject to the accuracy of the representations and warranties on the part of the Company set forth in Section 1 hereof as of the date hereof and as of the First Closing Date as though then made and, with respect to the Optional Shares, as of each Option Closing Date as though then made, to the timely performance by the Company of its covenants and other obligations hereunder, and to each of the following additional conditions:

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(a)                                 Comfort Letter.  On the date hereof, the Representatives shall have received from KPMG LLP, independent registered public accountants for the Company, a letter dated the date hereof addressed to the Underwriters, in form and substance satisfactory to the Representatives, containing statements and information of the type ordinarily included in accountant’s “comfort letters” to underwriters, delivered according to Statement of Auditing Standards No. 72 (or any successor bulletin), with respect to the audited and unaudited financial statements and certain financial information contained in the Registration Statement, the Time of Sale Prospectus, and each free writing prospectus, if any.

(b)                                 Compliance with Registration Requirements; No Stop Order; No Objection from FINRA.

(i)                                     The Company shall have filed the Prospectus with the Commission (including the information previously omitted from the Registration Statement pursuant to Rule 430B under the Securities Act) in the manner and within the time period required by Rule 424(b) under the Securities Act.

(ii)                                  No stop order suspending the effectiveness of the Registration Statement or any post-effective amendment to the Registration Statement shall be in effect, and no proceedings for such purpose shall have been instituted or threatened by the Commission.

(iii)                               If a filing has been made with FINRA, FINRA shall have raised no objection to the fairness and reasonableness of the underwriting terms and arrangements.

(c)                                  No Material Adverse Change or Ratings Agency Change.  For the period from and after the date of this Agreement and through and including the First Closing Date and, with respect to any Optional Shares purchased after the First Closing Date, each Option Closing Date:

(i)                                     in the judgment of the Representatives there shall not have occurred any Material Adverse Change; and

(ii)                                  there shall not have occurred any downgrading, nor shall any notice have been given of any intended or potential downgrading or of any review for a possible change that does not indicate the direction of the possible change, in the rating accorded any securities of the Company or any of its subsidiaries by any “nationally recognized statistical rating organization” as such term is defined for purposes of Rule 436(g)(2) under the Securities Act.

(d)                                 Opinion of Counsel for the Company.  On each of the First Closing Date and each Option Closing Date, the Representatives shall have received the opinion of Gross Hartman LLC, counsel for the Company, dated as of such date, in the form attached hereto as Exhibit A and to such further effect as the Representatives shall reasonably request, with executed copies for each of the other Underwriters named on the Prospectus cover page.

(e)                                  Opinion of Regulatory Counsel for the Company.  On each of the First Closing Date and each Option Closing Date, the Representatives shall have received the opinion of Hogan Lovells US LLP, regulatory counsel for the Company, dated as of such date, the form of which is attached as Exhibit B and to such further effect as counsel for the Underwriters shall reasonably request, with executed copies for each of the other Underwriters named on the Prospectus cover page.

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(f)                                   Opinion of General Counsel of the Company.  On each of the First Closing Date and each Option Closing Date, the Representatives shall have received the opinion of John R. Moore, Vice President and General Counsel of the Company, dated as of such date, in the form attached hereto as Exhibit C and to such further effect as the Representatives shall reasonably request, with executed copies for each of the other Underwriters named on the Prospectus cover page.

(g)                                  Opinion of Counsel for the Underwriters.  On each of the First Closing Date and each Option Closing Date, the Representatives shall have received the opinion of Latham & Watkins LLP, counsel for the Underwriters in connection with the offer and sale of the Offered Shares, in form and substance satisfactory to the Underwriters, dated as of such date, with executed copies for each of the other Underwriters named on the Prospectus cover page.

(h)                                 Officers’ Certificate.  On each of the First Closing Date and each Option Closing Date, the Representatives shall have received a certificate executed by the Chief Executive Officer or President of the Company and the Chief Financial Officer of the Company, dated as of such date, with executed copies for each of the other Underwriters named on the Prospectus cover page, to the effect set forth in Section 6(b)(ii) and further to the effect that:

(i)                                     for the period from and including the date of this Agreement through and including such date, there has not occurred any Material Adverse Change;

(ii)                                  the representations, warranties and covenants of the Company set forth in Section 1 of this Agreement are true and correct with the same force and effect as though expressly made on and as of such date; and

(iii)                               the Company has complied with all the agreements hereunder and satisfied all the conditions on its part to be performed or satisfied hereunder at or prior to such date.

(i)                                     Bring-down Comfort Letter.  On each of the First Closing Date and each Option Closing Date the Representatives shall have received from KPMG LLP, independent registered public accountants for the Company, a letter dated such date, in form and substance satisfactory to the Representatives, with executed copies for each of the other Underwriters named on the Prospectus cover page, which letter shall: (i) reaffirm the statements made in the letter furnished by them pursuant to Section 6(a), except that the specified date referred to therein for the carrying out of procedures shall be no more than three business days prior to the First Closing Date or the applicable Option Closing Date, as the case may be; and (ii) cover certain financial information contained in the Prospectus.

(j)                                    Lock-up Agreements.  On or prior to the date hereof, the Company shall have furnished to the Representatives an agreement in the form of Exhibit D hereto from each of the persons listed on Exhibit E hereto, and each such agreement shall be in full force and effect on each of the First Closing Date and each Option Closing Date.

(k)                                 Rule 462(b) Registration Statement.  In the event that a Rule 462(b) Registration Statement is filed in connection with the offering contemplated by this Agreement, such Rule 462(b) Registration Statement shall have been filed with the Commission on the date of this Agreement and shall have become effective automatically upon such filing.

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(l)                                     Additional Documents.  On or before each of the First Closing Date and each Option Closing Date, the Representatives and counsel for the Underwriters shall have received such information, documents and opinions as they may reasonably request for the purposes of enabling them to pass upon the issuance and sale of the Offered Shares as contemplated herein, or in order to evidence the accuracy of any of the representations and warranties, or the satisfaction of any of the conditions or agreements, herein contained; and all proceedings taken by the Company in connection with the issuance and sale of the Offered Shares as contemplated herein and in connection with the other transactions contemplated by this Agreement shall be reasonably satisfactory in form and substance to the Representatives and counsel for the Underwriters.

If any condition specified in this Section 6 is not satisfied when and as required to be satisfied, this Agreement may be terminated by the Representatives by notice from the Representatives to the Company at any time on or prior to the First Closing Date and, with respect to the Optional Shares, at any time on or prior to the applicable Option Closing Date, which termination shall be without liability on the part of any party to any other party, except that Section 4, Section 7, Section 9 and Section 10 shall at all times be effective and shall survive such termination.

Section 7.                                          Reimbursement of Underwriters’ Expenses.  If this Agreement is terminated by the Representatives pursuant to Section 6, Section 11 or Section 12, or if the sale to the Underwriters of the Offered Shares on the First Closing Date is not consummated because of any refusal, inability or failure on the part of the Company to perform any agreement herein or to comply with any provision hereof, the Company agrees to reimburse the Representatives and the other Underwriters (or such Underwriters as have terminated this Agreement with respect to themselves), severally, upon demand for all documented out-of-pocket expenses that shall have been reasonably incurred by the Representatives and the Underwriters in connection with the proposed purchase and the offering and sale of the Offered Shares, including but not limited to reasonable fees and disbursements of counsel, printing expenses, travel expenses, postage, facsimile and telephone charges.

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

Section 9.                                          Indemnification.

(a)                                 Indemnification of the Underwriters.  The Company agrees to indemnify and hold harmless each Underwriter, its affiliates, directors, officers, employees and agents, and each person, if any, who controls any Underwriter within the meaning of the Securities Act or the Exchange Act against any loss, claim, damage, liability or expense, as incurred, to which such Underwriter or such affiliate, director, officer, employee, agent or controlling person may become subject, under the Securities Act, the Exchange Act, other federal or state statutory law or regulation, or the laws or regulations of foreign jurisdictions where Offered Shares have been offered or sold or at common law or otherwise (including in settlement of any litigation, if such settlement is effected with the written consent of the Company), insofar as such loss, claim, damage, liability or expense (or actions in respect thereof as contemplated below) arises out of or is based upon (i) any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, or any amendment thereto, or the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading; or (ii) any untrue statement or alleged untrue statement of a material fact included in any preliminary prospectus, the Time of Sale Prospectus, any free writing prospectus that the Company has used, referred to or filed, or is required to file, pursuant to Rule 433(d) of

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the Securities Act or the Prospectus (or any amendment or supplement to the foregoing), or the omission or alleged omission to state therein a material fact necessary in order to make the statements, in the light of the circumstances under which they were made, not misleading; and to reimburse each Underwriter and each such affiliate, director, officer, employee, agent and controlling person for any and all documented expenses (including the reasonable fees and disbursements of counsel) as such expenses are incurred by such Underwriter or such affiliate, director, officer, employee, agent or controlling person in connection with investigating, defending, settling, compromising or paying any such loss, claim, damage, liability, expense or action; provided, however, that the foregoing indemnity agreement shall not apply to any loss, claim, damage, liability or expense to the extent, but only to the extent, arising out of or based upon any untrue statement or alleged untrue statement or omission or alleged omission made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company by the Representatives in writing expressly for use in the Registration Statement, any preliminary prospectus, the Time of Sale Prospectus, any such free writing prospectus or the Prospectus (or any amendment or supplement thereto), it being understood and agreed that the only such information consists of the information described in Section 9(b) below.  The indemnity agreement set forth in this Section 9(a) shall be in addition to any liabilities that the Company may otherwise have.

(b)                                 Indemnification of the Company, its Directors and Officers.  Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, each of its directors, each of its officers who signed the Registration Statement and each person, if any, who controls the Company within the meaning of the Securities Act or the Exchange Act, against any loss, claim, damage, liability or expense, as incurred, to which the Company, or any such director, officer or controlling person may become subject, under the Securities Act, the Exchange Act, or other federal or state statutory law or regulation, or at common law or otherwise (including in settlement of any litigation, if such settlement is effected with the written consent of such Underwriter), insofar as such loss, claim, damage, liability or expense (or actions in respect thereof as contemplated below) arises out of or is based upon (i) any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, or any amendment thereto, or any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading or (ii) any untrue statement or alleged untrue statement of a material fact included in any preliminary prospectus, the Time of Sale Prospectus, any free writing prospectus that the Company has used, referred to or filed, or is required to file, pursuant to Rule 433 of the Securities Act, or the Prospectus (or any such amendment or supplement) or the omission or alleged omission to state therein a material fact necessary in order to make the statements, in the light of the circumstances under which they were made, not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in the Registration Statement, such preliminary prospectus, the Time of Sale Prospectus, such free writing prospectus, the Prospectus (or any such amendment or supplement), in reliance upon and in conformity with information relating to such Underwriter furnished to the Company by the Representatives in writing expressly for use therein; and to reimburse the Company, or any such director, officer or controlling person for any and all documented expenses (including the reasonable fees and disbursements of counsel) as such expenses are incurred by the Company, or any such director, officer or controlling person in connection with investigating, defending, settling, compromising or paying any such loss, claim, damage, liability, expense or action.  The Company hereby acknowledges that the only information that the Representatives have furnished to the Company expressly for use in the Registration Statement, any preliminary prospectus, the Time of Sale Prospectus, any free writing prospectus that the Company has filed, or is required to file, pursuant to Rule 433(d) of the Securities Act, or the Prospectus (or any amendment or

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supplement to the foregoing) are the statements set forth in the first sentence of the fourth paragraph, the first two sentences of the first paragraph under the title “Commissions and Expenses” and the statements in the first and fourth paragraphs immediately below the title “Stabilization,” in each case under the caption “Underwriting,” in the Prospectus. The indemnity agreement set forth in this Section 9(b) shall be in addition to any liabilities that each Underwriter may otherwise have.

(c)                                  Notifications and Other Indemnification Procedures.  Promptly after receipt by an indemnified party under this Section 9 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against an indemnifying party under this Section 9, notify the indemnifying party in writing of the commencement thereof, but the omission so to notify the indemnifying party will not relieve the indemnifying party from any liability which it may have to any indemnified party to the extent the indemnifying party is not materially prejudiced as a proximate result of such failure and shall not in any event relieve the indemnifying party from any liability that it may have otherwise than on account  of this indemnity agreement.  In case any such action is brought against any indemnified party and such indemnified party seeks or intends to seek indemnity from an indemnifying party, the indemnifying party will be entitled to participate in, and, to the extent that it shall elect, jointly with all other indemnifying parties similarly notified, by written notice delivered to the indemnified party promptly after receiving the aforesaid notice from such indemnified party, to assume the defense thereof with counsel reasonably satisfactory to such indemnified party; provided, however, that if the defendants in any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that a conflict may arise between the positions of the indemnifying party and the indemnified party in conducting the defense of any such action or that there may be legal defenses available to it and/or other indemnified parties which are different from or additional to those available to the indemnifying party, the indemnified party or parties shall have the right to select separate counsel to assume such legal defenses and to otherwise participate in the defense of such action on behalf of such indemnified party or parties.  Upon receipt of notice from the indemnifying party to such indemnified party of such indemnifying party’s election so to assume the defense of such action and approval by the indemnified party of counsel, the indemnifying party will not be liable to such indemnified party under this Section 9 for any legal or other expenses subsequently incurred by such indemnified party in connection with the defense thereof unless (i) the indemnified party shall have employed separate counsel in accordance with the proviso to the preceding sentence (it being understood, however, that the indemnifying party shall not be liable for the fees and expenses of more than one separate counsel (together with local counsel), representing the indemnified parties who are parties to such action), which counsel (together with any local counsel) for the indemnified parties shall be selected by the Representatives (in the case of counsel for the indemnified parties referred to in Section 9(a) above) or by the Company (in the case of counsel for the indemnified parties referred to in Section 9(b) above)) or (ii) the indemnifying party shall not have employed counsel satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of commencement of the action or (iii) the indemnifying party has authorized in writing the employment of counsel for the indemnified party at the expense of the indemnifying party, in each of which cases the fees and expenses of counsel shall be at the expense of the indemnifying party and shall be paid as they are incurred.

(d)                                 Settlements.  The indemnifying party under this Section 9 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 party agrees to indemnify the indemnified party against any loss, claim, damage, liability or expense by reason of

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such settlement or judgment.  Notwithstanding the foregoing sentence, if at any time an indemnified party shall have requested an indemnifying party to reimburse the indemnified party for fees and expenses of counsel as contemplated by Section 9(c) hereof, the indemnifying party 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 such indemnifying party of the aforesaid request and (ii) such indemnifying party shall not have reimbursed the indemnified party in accordance with such request prior to the date of such settlement.  No indemnifying party shall, without the prior written consent of the indemnified party, effect any settlement, compromise or consent to the entry of judgment in any pending or threatened action, suit or proceeding in respect of which any indemnified party is or could have been a party and indemnity was or could have been sought hereunder by such indemnified party, unless such settlement, compromise or consent includes an unconditional release of such indemnified party from all liability on claims that are the subject matter of such action, suit or proceeding and does not include an admission of fault or culpability or a failure to act by or on behalf of such indemnified party.

Section 10.                                   Contribution.  If the indemnification provided for in Section 9 is for any reason held to be unavailable to or otherwise insufficient to hold harmless an indemnified party in respect of any losses, claims, damages, liabilities or expenses referred to therein, then each indemnifying party shall contribute to the aggregate amount paid or payable by such indemnified party, as incurred, as a result of any losses, claims, damages, liabilities or expenses referred to therein (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 hand, from the offering of the Offered Shares pursuant to this Agreement or (ii) if the allocation provided by clause (i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) above but also the relative fault of the Company, on the one hand, and the Underwriters, on the other hand, in connection with the statements or omissions which resulted in such losses, claims, damages, liabilities or expenses, 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 hand, in connection with the offering of the Offered Shares pursuant to this Agreement shall be deemed to be in the same respective proportions as the total proceeds from the offering of the Offered Shares pursuant to this Agreement (before deducting expenses) received by the Company, and the total underwriting discounts and commissions received by the Underwriters, in each case as set forth on the front cover page of the Prospectus, bear to the aggregate initial public offering price of the Offered Shares as set forth on such cover.  The relative fault of the Company, on the one hand, and the Underwriters, on the other hand, shall be determined by reference to, among other things, whether any such untrue or alleged untrue statement of a material fact or omission or alleged omission to state a material fact relates to information supplied by the Company, on the one hand, or the Underwriters, on the other hand, and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

The amount paid or payable by a party as a result of the losses, claims, damages, liabilities and expenses referred to above shall be deemed to include, subject to the limitations set forth in Section 9(c), any legal or other fees or expenses reasonably incurred by such party in connection with investigating or defending any action or claim.  The provisions set forth in Section 9(c) with respect to notice of commencement of any action shall apply if a claim for contribution is to be made under this Section 10; provided, however, that no additional notice shall be required with respect to any action for which notice has been given under Section 9(c) for purposes of indemnification.

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The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 10 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 which does not take account of the equitable considerations referred to in this Section 10.

Notwithstanding the provisions of this Section 10, no Underwriter shall be required to contribute any amount in excess of the underwriting discounts and commissions received by such Underwriter in connection with the Offered Shares underwritten by it and distributed to the public.  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 this Section 10 are several, and not joint, in proportion to their respective underwriting commitments as set forth opposite their respective names on Schedule A.  For purposes of this Section 10, each affiliate, director, officer, employee and agent of an Underwriter and each person, if any, who controls an Underwriter within the meaning of the Securities Act or the Exchange Act shall have the same rights to contribution as such Underwriter, and each director of the Company, each officer of the Company who signed the Registration Statement, and each person, if any, who controls the Company within the meaning of the Securities Act and the Exchange Act shall have the same rights to contribution as the Company.

Section 11.                                   Default of One or More of the Several Underwriters.  If, on the First Closing Date or any Option Closing Date, any one or more of the several Underwriters shall fail or refuse to purchase Offered Shares that it or they have agreed to purchase hereunder on such date, and the aggregate number of Offered Shares which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase does not exceed 10% of the aggregate number of the Offered Shares to be purchased on such date, the Representatives may make arrangements satisfactory to the Company for the purchase of such Offered Shares by other persons, including any of the Underwriters, but if no such arrangements are made by such date, the other Underwriters shall be obligated, severally and not jointly, in the proportions that the number of Firm Shares set forth opposite their respective names on Schedule A bears to the aggregate number of Firm Shares set forth opposite the names of all such non-defaulting Underwriters, or in such other proportions as may be specified by the Representatives with the consent of the non-defaulting Underwriters, to purchase the Offered Shares which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase on such date. If, on the First Closing Date or any Option Closing Date any one or more of the Underwriters shall fail or refuse to purchase Offered Shares and the aggregate number of Offered Shares with respect to which such default occurs exceeds 10% of the aggregate number of Offered Shares to be purchased on such date, and arrangements satisfactory to the Representatives and the Company for the purchase of such Offered Shares are not made within 48 hours after such default, this Agreement shall terminate without liability of any party other than the defaulting Underwriter to any other party except that the provisions of Section 4, Section 7, Section 9 and Section 10 shall at all times be effective and shall survive such termination, except that the Company shall not be obligated to reimburse the expenses of the defaulting Underwriter pursuant to Section 4 or Section 7 hereof.  In any such case either the Representatives or the Company shall have the right to postpone the First Closing Date or the applicable Option Closing Date, as the case may be, but in no event for longer than seven days in order that the required changes, if any, to the Registration Statement and the Prospectus or any other documents or arrangements may be effected.

As used in this Agreement, the term “Underwriter” shall be deemed to include any person substituted for a defaulting Underwriter under this Section 11.  Any action taken

28

under this Section 11 shall not relieve any defaulting Underwriter from liability in respect of any default of such Underwriter under this Agreement.

Section 12.                                   Termination of this Agreement.  Prior to the purchase of the Firm Shares by the Underwriters on the First Closing Date, this Agreement may be terminated by the Representatives by notice given to the Company if at any time: (i) trading or quotation in any of the Company’s securities shall have been suspended or limited by the Commission or by the NASDAQ, or trading in securities generally on either the NASDAQ or the NYSE shall have been suspended or limited, or minimum or maximum prices shall have been generally established on any of such stock exchanges; (ii) a general banking moratorium shall have been declared by any of federal, New York, Delaware or Colorado authorities; (iii) there shall have occurred any outbreak or escalation of national or international hostilities or any crisis or calamity, or any change in the United States or international financial markets, or any substantial change or development involving a prospective substantial change in United States’ or international political, financial or economic conditions, as in the judgment of the Representatives is material and adverse and makes it impracticable to market the Offered Shares in the manner and on the terms described in the Time of Sale Prospectus or the Prospectus or to enforce contracts for the sale of securities; (iv) in the judgment of the Representatives there shall have occurred any Material Adverse Change; or (v) the Company shall have sustained a loss by strike, fire, flood, earthquake, accident or other calamity of such character as in the  judgment of the Representatives may interfere materially with the conduct of the business and operations of the Company regardless of whether or not such loss shall have been insured.  Any termination pursuant to this Section 12 shall be without liability on the part of (a) the Company to any Underwriter, except that the Company shall be obligated to reimburse the expenses of the Representatives and the Underwriters pursuant to Section 4 or Section 7 hereof or (b) any Underwriter to the Company; provided, however, that the provisions of Section 9 and Section 10 shall at all times be effective and shall survive such termination.

Section 13.                                   No Advisory or Fiduciary Relationship.  The Company acknowledges and agrees that (a) the purchase and sale of the Offered Shares pursuant to this Agreement, including the determination of the public offering price of the Offered Shares and any related discounts and commissions, is an arm’s-length commercial transaction between the Company, on the one hand, and the several Underwriters, on the other hand, (b) in connection with the offering contemplated hereby and the process leading to such transaction, each Underwriter is and has been acting solely as a principal and is not the agent or fiduciary of the Company, or its stockholders, creditors, employees or any other party, (c) no Underwriter has assumed or will assume an advisory or fiduciary responsibility in favor of the Company with respect to the offering contemplated hereby or the process leading thereto (irrespective of whether such Underwriter has advised or is currently advising the Company on other matters) and no Underwriter has any obligation to the Company with respect to the offering contemplated hereby except the obligations expressly set forth in this Agreement, (d) the Underwriters and their respective affiliates may be engaged in a broad range of transactions that involve interests that differ from those of the Company, and (e) the Underwriters have not provided any legal, accounting, regulatory or tax advice with respect to the offering contemplated hereby and the Company has consulted its own legal, accounting, regulatory and tax advisors to the extent it deemed appropriate.

Section 14.                                   Representations and Indemnities to Survive Delivery.  The respective indemnities, agreements, representations, warranties and other statements of the Company, of its officers and of the several Underwriters set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation made by or on

29

behalf of any Underwriter or the Company or any of its or their partners, officers or directors or any controlling person, as the case may be, and, anything herein to the contrary notwithstanding, will survive delivery of and payment for the Offered Shares sold hereunder and any termination of this Agreement.

Section 15.            Notices.  All communications hereunder shall be in writing and shall be mailed, hand delivered or telecopied and confirmed to the parties hereto as follows:

If to the Representatives:

Jefferies & Company, Inc.

520 Madison Avenue

New York, New York 10022

Facsimile:  (646) 619-4437    

Attention:  General Counsel

J.P. Morgan Securities LLC

383 Madison Avenue

New York, New York 10019

Attention: Equity Syndicate Desk

with a copy to:

Latham & Watkins

650 Town Center Drive, 20th Floor

Costa Mesa, California 92626

Facsimile:  (714) 755-8290

Attention: B. Shayne Kennedy

If to the Company:

Array BioPharma Inc.

3200 Walnut Street

Boulder, Colorado

Facsimile:  (303) 386-1390

Attention:  R. Michael Carruthers, Chief Financial Officer

with a copy to:

Gross Hartman LLC

1877 Broadway, Suite 601

Boulder, Colorado 80302

Facsimile: (303) 648-5529

Attention: Carin M. Cutler

Any party hereto may change the address for receipt of communications by giving written notice to the others.

Section 16.            Successors.  This Agreement will inure to the benefit of and be binding upon the parties hereto, including any substitute Underwriters pursuant to Section 11 hereof, and to the benefit of the affiliates, directors, officers, employees, agents and controlling

30

persons referred to in Section 9 and Section 10, and in each case their respective successors, and no other person will have any right or obligation hereunder.  The term “successors” shall not include any purchaser of the Offered Shares as such from any of the Underwriters merely by reason of such purchase.

Section 17.            Partial Unenforceability.  The invalidity or unenforceability of any section, paragraph or provision of this Agreement shall not affect the validity or enforceability of any other section, paragraph or provision hereof.  If any section, paragraph or provision of this Agreement is for any reason determined to be invalid or unenforceable, there shall be deemed to be made such minor changes (and only such minor changes) as are necessary to make it valid and enforceable.

Section 18.            Governing Law Provisions.  This Agreement shall be governed by and construed in accordance with the internal laws of the State of New York applicable to agreements made and to be performed in such state.  Any legal suit, action or proceeding arising out of or based upon this Agreement or the transactions contemplated hereby (“Related Proceedings”) may be instituted in the federal courts of the United States of America located in the Borough of Manhattan in the City of New York or the courts of the State of New York in each case located in the Borough of Manhattan in the City of New York (collectively, the “Specified Courts”), and each party irrevocably submits to the exclusive jurisdiction (except for proceedings instituted in regard to the enforcement of a judgment of any such court (a “Related Judgment”), as to which such jurisdiction is non-exclusive) of such courts in any such suit, action or proceeding.  Service of any process, summons, notice or document by mail to such party’s address set forth above shall be effective service of process for any suit, action or other proceeding brought in any such court.  The parties irrevocably and unconditionally waive any objection to the laying of venue of any suit, action or other proceeding in the Specified Courts and irrevocably and unconditionally waive and agree not to plead or claim in any such court that any such suit, action or other proceeding brought in any such court has been brought in an inconvenient forum.

With respect to any Related Proceeding, each party irrevocably waives, to the fullest extent permitted by applicable law, all immunity (whether on the basis of sovereignty or otherwise) from jurisdiction, service of process, attachment (both before and after judgment) and execution to which it might otherwise be entitled in the Specified Courts, and with respect to any Related Judgment, each party waives any such immunity in the Specified Courts or any other court of competent jurisdiction, and will not raise or claim or cause to be pleaded any such immunity at or in respect of any such Related Proceeding or Related Judgment, including, without limitation, any immunity pursuant to the United States Foreign Sovereign Immunities Act of 1976, as amended.

Section 19.            General Provisions.  This Agreement constitutes the entire agreement of the parties to this Agreement and supersedes all prior written or oral and all contemporaneous oral agreements, understandings and negotiations with respect to the subject matter hereof.  This Agreement may be executed in two or more counterparts, each one of which shall be an original, with the same effect as if the signatures thereto and hereto were upon the same instrument.  This Agreement may not be amended or modified unless in writing by all of the parties hereto, and no condition herein (express or implied) may be waived unless waived in writing by each party whom the condition is meant to benefit.  The section headings herein are for the convenience of the parties only and shall not affect the construction or interpretation of this Agreement.

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Each of the parties hereto acknowledges that it is a sophisticated business person who was adequately represented by counsel during negotiations regarding the provisions hereof, including, without limitation, the indemnification provisions of Section 9 and the contribution provisions of Section 10, and is fully informed regarding said provisions.  Each of the parties hereto further acknowledges that the provisions of Section 9 and Section 10 hereof fairly allocate the risks in light of the ability of the parties to investigate the Company, its affairs and its business in order to assure that adequate disclosure has been made in the Registration Statement, any preliminary prospectus, the Time of Sale Prospectus, each free writing prospectus and the Prospectus (and any amendments and supplements to the foregoing), as contemplated by the Securities Act and the Exchange Act.

[Signature Page Follows]

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If the foregoing is in accordance with your understanding of our agreement, kindly sign and return to the Company the enclosed copies hereof, whereupon this instrument, along with all counterparts hereof, shall become a binding agreement in accordance with its terms.

The foregoing Underwriting Agreement is hereby confirmed and accepted by the Representatives in New York, New York as of the date first above written.

[Signature Page to Underwriting Agreement]

SCHEDULE A

SCHEDULE B

Free Writing Prospectuses Included in the Time of Sale Prospectus

None

SCHEDULE C

PRICING INFORMATION

18,000,000 Shares

A shelf registration statement relating to the shares of common stock being issued in the offering has been filed with the Securities and Exchange Commission (the “SEC”) and is effective.  A preliminary prospectus supplement relating to the offering has been filed with the SEC and a final prospectus supplement relating to the offering will be filed with the SEC.  Copies of the final prospectus supplement and accompanying prospectus, when available, may be obtained from either: Jefferies & Company, Inc., Equity Syndicate Prospectus Department, at 520 Madison Avenue, New York, New York, 10022, or by calling (877) 547-6340, or by emailing Prospectus_Department@Jefferies.com; or J.P. Morgan Securities LLC, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, New York 11717, or by calling (866) 803-9204.  This term sheet shall not constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of, these securities in any state or other jurisdiction in which such offer, solicitation or sale would be unlawful prior to the registration or qualification under the securities laws of any such state or jurisdiction.

EXHIBIT A

Form of Opinion of Company Counsel

Based upon, subject to and limited by the assumptions, qualifications, exceptions, and limitations set forth in this opinion letter, we are of the opinion that:

(a)           The Company is (i) validly existing as a corporation and in good standing under the laws of the State of Delaware as of the date of the Good Standing Certificate; and (ii) authorized to transact business as a foreign corporation in the State of Colorado as of the date set forth in the Foreign Qualification Certificate.

(b)           The Company has the corporate power to own, lease and operate its current properties, and to conduct its business, as described in the Prospectus.

(c)           The Agreement has been duly authorized, executed and delivered by the Company.

(d)           The Shares have been duly authorized and, when issued in accordance with the provisions of the Agreement, will be validly issued, fully paid and non-assessable and the issuance of the Shares is not subject to any statutory preemptive right under the Corporation Act or, to our knowledge, any contractual right to subscribe for any of the Shares.

(e)           To our knowledge, no stop order suspending the effectiveness of the Registration Statement or suspending or preventing the use of the Prospectus has been issued and no proceedings for that purpose have been instituted or are threatened by the Commission.  The required filing of the Final Prospectus Supplement pursuant to Rule 424(b) promulgated pursuant to the Securities Act has been made in the manner and within the time period required by Rule 424(b).

(f)            The Registration Statement and the Prospectus (except for the financial statements and supporting schedules included therein and to any other financial or statistical data derived therefrom, as to which we express no opinion) comply as to form in all material respects with the requirements of the Securities Act and the applicable rules and regulations thereunder.  The documents incorporated by reference pursuant to Item 12 of Form S-3 under the Securities Act in the Prospectus (except for the financial statements and supporting schedules included therein and to any other financial or statistical data derived therefrom, as to which we express no opinion), at the time they became effective or were filed with the Commission, as the case may be, complied as to form in all material respects with the requirements of the Exchange Act and the applicable rules and regulations thereunder.

(g)           The information in (i) the Company’s annual report filed on Form 10-K for the fiscal year ended June 30, 2012 (the “Form 10-K”) under the caption “Partnered Development Programs”, (ii) the Base Prospectus under the caption “Description of Capital Stock”; and (iii) the Registration Statement under the caption “Item 15. Indemnification of Directors and Officers,” insofar as such statements purport to summarize legal matters, agreements or documents discussed therein, fairly present, to the extent required by the Securities Act and the rules thereunder, in all material respects, such legal matters, agreements or documents.

(h)           The execution and delivery on November 9, 2012, and the performance on the date hereof, by the Company of the Agreement do not (i) violate the Certificate of Incorporation or Bylaws of the Company, (ii) violate the Corporation Act or any provision of Applicable State Law or any provision of Applicable Federal Law, (iii)

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violate any of the Company Orders, or (iv) breach or constitute a default under any of the Company Contracts (except that we express no opinion with respect to any matters that (x) would require a mathematical calculation or a financial or accounting determination, or (y) any statement or writing that may constitute parol evidence bearing on interpretation or construction).

(i)            No approval or consent of, or registration or filing with, any federal or Colorado state governmental or regulatory agency or body is required to be obtained or made by the Company under Applicable Federal Law or Applicable State Law, and no approval of the stockholders of the Company is required to be obtained by the Company under the Corporation Act in connection with the performance on the date hereof by the Company of the Agreement.

(j)            The Company is not, and after giving effect to the offering and the sale of the Shares and assuming the application of the net proceeds therefrom as described in the Prospectus will not be, an “investment company” within the meaning of the Investment Company Act.

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[Form Negative Assurance Letter of Company Counsel]

Subject to the foregoing, we confirm to you that, on the basis of the information we gained in the course of performing the services referred to above, no facts have come to our attention that cause us to believe that:

(i)            the Registration Statement, as of the date of the Agreement, in so far as it relates to the offering of the Shares, contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading; or

(ii)           the Prospectus, as of its date or as of the date hereof, in so far as it relates to the offering of the Shares, contained or contains an untrue statement of a material fact or omitted or omits 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 in making the foregoing statements, we do not express any belief with respect to the financial statements and supporting schedules and other financial or accounting information and data, or statistical information, derived from such financial statements and schedules or the books and records of the Company, or assessments of or reports on the effectiveness of internal control over financial reporting contained or incorporated by reference in or omitted from the Registration Statement or the Prospectus.

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EXHIBIT B

Form of Opinion of Hogan Lovells US LLP

Based upon, subject to and limited by the assumptions, qualifications, exceptions, and limitations set forth in this opinion letter, we are of the opinion that the statements under the Regulatory Captions, insofar as such statements purport to summarize applicable provisions of the Federal Food, Drug and Cosmetic Act, as amended, and the regulations promulgated thereunder, Title XVIII of the SSA, as amended by the Medicare Prescription Drug, Improvement and Modernization Act of 2003, and the regulations promulgated thereunder, Titles XVIII and XIX of the SSA and section 340B of the PHS Act, as amended by the Patient Protection and Affordable Care Act, and the regulations promulgated thereunder, Titles XVIII and XIX of the SSA and section 340B of the PHS Act, as amended by the Health Care and Education Reconciliation Act of 2010, and the regulations promulgated thereunder, Title XIX of the SSA, as amended by the FAA Air Transportation Modernization and Safety Improvement Act, and the Health Insurance Portability and Accountability Act of 1996, as amended by the Health Information Technology for Economic and Clinical Health Act, and the regulations promulgated thereunder, are accurate summaries in all material respects.

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EXHIBIT C

Form of Opinion of General Counsel

Based upon, subject to and limited by the assumptions, qualifications, exceptions, and limitations set forth in this opinion letter, I am of the opinion that:

(a)           The information in the Company’s Annual Report on Form 10-K for the fiscal year ended June 30, 2012 as filed with the United States Securities and Exchange Commission (the “Commission”) on August 16, 2012 (the “Form 10-K”) under the caption “Drug Discovery and Clinical Development Programs — Partnered Development Programs”; under the captions “Risk Factors — Risks Related to Our Business — Our drug candidates are at early stages of development, and we may not successfully develop a drug candidate that becomes a commercially viable drug”, “Risk Factors — Risks Related to Our Business — Because we rely on a small number of collaborators for a significant portion of our revenue, if one or more of our major collaborators terminates or reduces the scope of their agreement with us, our revenue may significantly decrease”, “Risk Factors — Risks Related to Our Clinical Development Activities and Obtaining Regulatory Approval for Our Programs — Our cGMP and pharmacology facilities and practices may fail to comply with government regulations,” “Risk Factors — Risks Related to Our Industry — The intellectual property rights we rely on to protect our proprietary drug candidates and the technology underlying our tools and techniques may be inadequate to prevent third parties from using our technology or developing competing capabilities or to protect our interests in our proprietary drug candidates”, and “Risk Factors — Risks Related to Our Industry — Agreements we have with our employees, consultants and collaborators may not afford adequate protection for our trade secrets, confidential information and other proprietary information”, in each case insofar as such statements purport to summarize legal matters, agreements or documents discussed therein, fairly present, to the extent required by the Securities Act and the rules thereunder, in all material respects, such legal matters, agreements or documents.

(b)           To my knowledge, the activities of the Company with respect to the commercialization of its product candidates, or the manufacture, use or sale thereof, do not infringe the patent of any third party.

(c)           To my knowledge, no patent that has issued or, after due prosecution will be issued, in each case in respect of any Application, is or would be invalid or unenforceable.

(d)           To my knowledge, the Company has complied with the United States Patent and Trademark Office’s duty of candor and disclosure for the U.S. Applications and has made no material misrepresentation in any Application.

(e)           I am not aware of any material fact with respect to the Applications that, after due prosecution, would preclude the issuance of patents with respect to such Applications.

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(f)            To my knowledge, no third party has stolen or misused the trade secrets, know-how or other proprietary rights of the Company. To my knowledge, the Company has not stolen or misused the trade secrets, know-how or other proprietary rights of any third party.

I hereby confirm to you as follows:

(A)          The Company is the sole assignee or joint owner of each U.S. Application other than U.S. Applications claiming the compound referred to by the Company as ARRY-300, which U.S. Applications are jointly owned by AstraZeneca PLC and the Company. I know of no other claims of third parties to any ownership interest with respect to any of such U.S. Applications. To my knowledge, none of such U.S. Applications has been abandoned.

(B)          The Company is the sole assignee or joint owner of each of the Non-U.S. Applications other than Non-U.S. Applications claiming the compound referred to by the Company as ARRY-300, which Non-U.S. Applications are jointly owned by AstraZeneca PLC and the Company. I know of no other claims of third parties to any ownership interest with respect to any of the Non-U.S. Applications. To my knowledge, none of the Non-U.S. Applications has been abandoned.

(C)          To my knowledge, there are no pending or threatened interference or opposition proceedings relating to the Applications. In addition to the assumptions, qualifications, exceptions and limitations elsewhere set forth in this opinion letter, the opinions expressed above are also subject to the effect of: (1) bankruptcy, insolvency, reorganization, receivership, moratorium and other laws affecting creditors’ rights (including, without limitation, the effect of statutory and other law regarding fraudulent conveyances, fraudulent transfers and preferential transfers); and (2) the exercise of judicial discretion and the application of principles of equity, good faith, fair dealing, reasonableness, conscionability and materiality (regardless of whether the applicable agreements are considered in a proceeding in equity or at law).

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[Form Negative Assurance Letter of General Counsel]

Subject to the foregoing, I confirm to you that, on the basis of the foregoing, no facts have come to my attention that cause me to believe that:

(i)      the information concerning the Intellectual Property in the Registration Statement, as of the date of the Agreement, in so far as it relates to the offering of the Shares, contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading;

(ii)     the information concerning the Intellectual Property in the Prospectus, as of its date or as of the date hereof, contained or contains an untrue statement of a material fact or omitted or omits 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;

(iii)    there are any legal or governmental proceedings pending or threatened against the Company relating to the Intellectual Property that are required to be disclosed in the Registration Statement or the Prospectus, other than those disclosed therein; or

(iv)    there are any contracts or documents relating to the Intellectual Property of a character required to be described in the Registration Statement or the Prospectus or to be filed as exhibits to the Registration Statement that are not described or referred to therein or so filed;

provided that in making the foregoing statements, I do not express any belief with respect to the financial statements and supporting schedules and other financial or accounting information and data, or statistical information, derived from such financial statements and schedules or the books and records of the Company, or assessments of or reports on the effectiveness of internal control over financial reporting contained or incorporated by reference in or omitted from the Registration Statement or the Prospectus.

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EXHIBIT D

Form of Lock-up Agreement

                    , 2012

Jefferies & Company, Inc.
J.P. Morgan Securities LLC
As Representatives of the Several Underwriters

c/o Jefferies & Company, Inc.
520 Madison Avenue
New York, New York 10022

and

c/o J.P. Morgan Securities LLC
383 Madison Avenue
New York, New York 10179

RE:                           Array BioPharma, Inc. (the “Company”)

Ladies & Gentlemen:

The undersigned is an owner of shares of common stock, par value $0.001 per share, of the Company (“Shares”) or of securities convertible into or exchangeable or exercisable for Shares.  The Company proposes to conduct a public offering of Shares (the “Offering”) for which Jefferies & Company, Inc. and J.P. Morgan Securities LLC will act as the representatives of the underwriters (in such capacity, the “Representatives”).  The undersigned recognizes that the Offering will benefit each of the Company and the undersigned.  The undersigned acknowledges that the underwriters are relying on the representations and agreements of the undersigned contained in this letter agreement in conducting the Offering and, at a subsequent date, in entering into an underwriting agreement (the “Underwriting Agreement”) and other underwriting arrangements with the Company with respect to the Offering.

Annex A sets forth definitions for capitalized terms used in this letter agreement that are not defined in the body of this agreement.  Those definitions are a part of this agreement.

In consideration of the foregoing, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the undersigned hereby agrees that, during the Lock-up Period, the undersigned will not (and will cause any Family Member not to), without the prior written consent of the Representatives, which may withhold their consent in their sole discretion:

D-1

·                  Sell or Offer to Sell any Shares or Related Securities currently or hereafter owned either of record or beneficially (as defined in Rule 13d-3 under the Exchange Act) by the undersigned or such Family Member,

·                  enter into any Swap,

·                  make any demand for, or exercise any right with respect to, the registration under the Securities Act of the offer and sale of any Shares or Related Securities, or cause to be filed a registration statement, prospectus or prospectus supplement (or an amendment or supplement thereto) with respect to any such registration, or

·                  publicly announce any intention to do any of the foregoing.

The foregoing will not apply to the registration of the offer and sale of the Shares, and the sale of the Shares to the underwriters, in each case as contemplated by the Underwriting Agreement.  In addition, the foregoing restrictions shall not apply to the transfer of Shares or Related Securities by gift, or by will or intestate succession to a Family Member or to a trust whose beneficiaries consist exclusively of one or more of the undersigned and/or a Family Member; provided, however, that in any such case, it shall be a condition to such transfer that:

·                  each transferee executes and delivers to the Representatives an agreement in form and substance satisfactory to the Representatives stating that such transferee is receiving and holding such Shares and/or Related Securities subject to the provisions of this letter agreement and agrees not to Sell or Offer to Sell such Shares and/or Related Securities, engage in any Swap or engage in any other activities restricted under this letter agreement except in accordance with this letter agreement (as if such transferee had been an original signatory hereto), and

·                  prior to the expiration of the Lock-up Period, no public disclosure or filing under the Exchange Act by any party to the transfer (donor, donee, transferor or transferee) shall be required, or made voluntarily, reporting a reduction in beneficial ownership of Shares in connection with such transfer.

The undersigned acknowledges and agrees that written notice by the Representatives to the Company of any extension of the 90-day initial lock-up period will be deemed to have been given to, and received by, the undersigned.  The undersigned further agrees that, prior to engaging in any transaction or taking any other action that is subject to the terms of this letter agreement during the period from the date of this letter agreement through the close of trading on the date that is the 34th day following the expiration of the 90-day initial lock-up period, the undersigned will give notice thereof to the Company and will not consummate any such transaction or take any such action unless the undersigned has received written confirmation from the Company that the Lock-Up Period has expired.

The undersigned also agrees and consents to the entry of stop transfer instructions with the Company’s transfer agent and registrar against the transfer of Shares or Related Securities held by the undersigned and the undersigned’s Family Members, if any, except in compliance with the foregoing restrictions.

With respect to the Offering only, the undersigned waives any registration rights relating to registration under the Securities Act of the offer and sale of any Shares and/or any Related Securities owned either of record or beneficially by the undersigned, including any rights to receive notice of the Offering.

D-2

The undersigned confirms that the undersigned has not, and has no knowledge that any Family Member has, directly or indirectly, taken any action designed to or that might reasonably be expected to cause or result in the stabilization or manipulation of the price of any security of the Company to facilitate the sale of the Shares.  The undersigned will not, and will cause any Family Member not to take, directly or indirectly, any such action.

Whether or not the Offering occurs as currently contemplated or at all depends on market conditions and other factors.  The Offering will only be made pursuant to the Underwriting Agreement, the terms of which are subject to negotiation between the Company and the underwriters.

The undersigned hereby represents and warrants that the undersigned has full power, capacity and authority to enter into this letter agreement.  This letter agreement is irrevocable and will be binding on the undersigned and the successors, heirs, personal representatives and assigns of the undersigned.

This letter agreement shall be governed by, and construed in accordance with, the laws of the State of New York.

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Certain Defined Terms
Used in Lock-up Agreement

For purposes of the letter agreement to which this Annex A is attached and of which it is made a part:

·                  “Call Equivalent Position” shall have the meaning set forth in Rule 16a-1(b) under the Exchange Act.

·                  “Exchange Act” shall mean the Securities Exchange Act of 1934, as amended.

·                  “Family Member” shall mean the spouse of the undersigned, an immediate family member of the undersigned or an immediate family member of the undersigned’s spouse, in each case living in the undersigned’s household or whose principal residence is the undersigned’s household (regardless of whether such spouse or family member may at the time be living elsewhere due to educational activities, health care treatment, military service, temporary internship or employment or otherwise).  “Immediate family member” as used above shall have the meaning set forth in Rule 16a-1(e) under the Exchange Act.

·                  “Lock-up Period” shall mean the period beginning on the date hereof and continuing through the close of trading on the date that is 90 days after the date of the Prospectus (as defined in the Underwriting Agreement); provided, that if (i) during the last 17 days of the 90-day initial lock-up period, the Company issues an earnings release or discloses material news or a material event relating to the Company occurs or (ii) prior to the expiration of such period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of such period, then in each case the Lock-up Period will be extended until the expiration of the 18-day period beginning on the date of the issuance of the earnings release or the disclosure of the material news or occurrence of the material event, as applicable, unless the Representatives waive, in writing, such extension.  If the initial lock-up period is extended pursuant to the provisions above, “Lock-up Period” shall mean the period described in the first clause of this paragraph, as so extended.

·                  “Put Equivalent Position” shall have the meaning set forth in Rule 16a-1(h) under the Exchange Act.

·                  “Related Securities” shall mean any options or warrants or other rights to acquire Shares or any securities exchangeable or exercisable for or convertible into Shares, or to acquire other securities or rights ultimately exchangeable or exercisable for or convertible into Shares.

·                  “Securities Act” shall mean the Securities Act of 1933, as amended.

·                  “Sell or Offer to Sell” shall mean to:

·                  sell, offer to sell, contract to sell or lend,

·                  effect any short sale or establish or increase a Put Equivalent Position or liquidate or decrease any Call Equivalent Position

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·                  pledge, hypothecate or grant any security interest in, or

·                  in any other way transfer or dispose of,

in each case whether effected directly or indirectly.

·                  “Swap” shall mean any swap, hedge or similar arrangement or agreement that transfers, in whole or in part, the economic risk of ownership of Shares or Related Securities, regardless of whether any such transaction is to be settled in securities, in cash or otherwise.

Capitalized terms not defined in this Annex A shall have the meanings given to them in the body of this lock-up agreement.

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EXHIBIT E

Directors and Officers Signing Lock-up Agreement

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