Pfenex Inc. (Form: 8-K, Received: 05/23/2018 17:21:21)

Pfenex Inc., a Delaware corporation (the “ Company ”), proposes to sell to the several Underwriters named in Schedule I hereto (the “ Underwriters ”) an aggregate of 6,800,000 shares (the “Firm Shares” ) of Common Stock, $0.001 par value per share (the “ Common Stock ”), of the Company. The Company has also granted to the several Underwriters an option to purchase up to 1,020,000 additional shares of Common Stock on the terms and for the purposes set forth in Section 3 hereof (the “ Option Shares ”). The Firm Shares and any Option Shares purchased pursuant to this Underwriting Agreement are herein collectively called the “ Securities. ”

The Company hereby confirms its agreement with respect to the sale of the Securities to the several Underwriters, for whom Barclays Capital Inc. (“ Barclays ”) and William Blair & Company, L.L.C. are acting as representatives (the “ Representatives ”).

1. Registration Statement and Prospectus . A registration statement on Form S-3 (File No. 333-206625) with respect to the Securities, including a base prospectus dated August 27, 2015 (the “ Base Prospectus ”), has been prepared by the Company in conformity with the requirements of the Securities Act of 1933, as amended (the “ Act ”), and the rules and regulations (“ Rules and Regulations ”) of the Securities and Exchange Commission (the “ Commission ”) thereunder and has been filed with the Commission. The term “ Registration Statement ” as used in this Agreement means the initial registration statement (including all exhibits, financial schedules and all documents and information deemed to be a part of the registration statement by incorporation by reference or otherwise, including pursuant to Rule 430A, 430B or 430C under the Securities Act), as amended at the time it became effective and as supplemented or amended, including the information, if any, contained in any preliminary prospectus or the final prospectus filed with the Commission pursuant to Rule 424(b) and Rule 430A, 430B or 430C under the Securities Act. If the Company has elected to rely upon Rule 462(b) of the Rules and

Regulations to increase the size of the offering registered under the Act, the Company will prepare and file with the Commission a registration statement with respect to such increase pursuant to Rule 462(b) of the Rules and Regulations (such registration statement, including the contents of the Registration Statement incorporated by reference therein is the “Rule 462(b) Registration Statement ”). References herein to the “ Registration Statement ” will be deemed to include the Rule 462(b) Registration Statement at and after the time of filing of the Rule 462(b) Registration Statement. “ Preliminary Prospectus ” means the Base Prospectus and any preliminary prospectus supplement used or filed with the Commission pursuant to Rule 424, in the form provided to the Underwriters by the Company for use in connection with the offering of the Securities. “ Prospectus ” means the Base Prospectus, any Preliminary Prospectus and any amendments or further supplements to such prospectus, and including, without limitation, the final prospectus supplement (the “ Prospectus Supplement ”) filed pursuant to and within the time limits described in Rule 424(b) with the Commission in connection with the proposed sale of the Shares contemplated by this Agreement. Any reference to any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Act as of the date of such Preliminary Prospectus or the Prospectus, as the case may be. Any reference to any amendment or supplement to any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any document filed under the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), after the date of such Preliminary Prospectus or the Prospectus, as the case may be, and before the date of such amendment or supplement and incorporated by reference in such Preliminary Prospectus or the Prospectus, as the case may be; and any reference to any amendment to the Registration Statement shall be deemed to include any document filed with the Commission pursuant to Section 13(a) or 15(d) of the Exchange Act after the effective date and before the date of such amendment that is incorporated by reference in the Registration Statement. All references in this Agreement to the Registration Statement, any Preliminary Prospectus, the Prospectus or any amendment or supplement to any of the foregoing, is deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System or any successor system thereto (“ EDGAR ”).

(a) Representations and Warranties of the Company . The Company represents and warrants to, and agrees with, the several Underwriters as follows:

(i) Registration Statement and Prospectuses . The Registration Statement and any post-effective amendment thereto has become effective under the Act. No stop order suspending the effectiveness of the Registration Statement, including any post-effective amendment thereto has been issued, and no proceeding for that purpose has been initiated or, to the Company’s knowledge, threatened by the Commission. No order preventing or suspending the use of any Preliminary Prospectus or the Prospectus (or any supplement thereto) has been issued by the Commission and no proceeding for that purpose has been initiated or, to the Company’s knowledge, threatened by the Commission. The Commission has not notified the Company of any objection to the use of the form of the Registration Statement or any post-effective amendment thereto. As of the time each part of the Registration Statement (including any post-effective amendment thereto) became or becomes effective, such part conformed or will conform in all material respects to the

requirements of the Act and the Rules and Regulations. Upon the filing or first use within the meaning of the Rules and Regulations, each Preliminary Prospectus and the Prospectus (or any supplement to either) conformed or will conform in all material respects to the requirements of the Act and the Rules and Regulations. The documents incorporated by reference in any Preliminary Prospectus or the Prospectus conformed, and any further documents so incorporated will conform, when filed with the Commission, in all material respects to the requirements of the Exchange Act or the Securities Act, as applicable, and the rules and regulations of the Commission thereunder.

(ii) Accurate Disclosure . Each Preliminary Prospectus, at the time of filing thereof or the time of first use within the meaning of the Rules and Regulations, did not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading. Neither the Registration Statement nor any amendment thereto, at the effective time of each part thereof, at the First Closing Date (as defined below) or at the Second Closing Date (as defined below), contained, contains or will contain an untrue statement of a material fact or omitted, omits or will omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading. As of the Time of Sale (as defined below), neither (A) the Time of Sale Disclosure Package (as defined below) nor (B) any issuer free writing prospectus (as defined below), when considered together with the Time of Sale Disclosure Package, included an untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading. Neither the Prospectus nor any supplement thereto, as of its issue date, at the time of any filing with the Commission pursuant to Rule 424(b) of the Rules and Regulations, at the First Closing Date or at the Second Closing Date, included, includes or will include an untrue statement of a material fact or omitted, omits or will omit to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading. The representations and warranties in this Section 2(a)(ii) shall not apply to statements in or omissions from any Preliminary Prospectus, the Registration Statement (including any amendment thereto), the Time of Sale Disclosure Package or the Prospectus (or any supplement thereto) made in reliance upon, and in conformity with, written information furnished to the Company by you, or by any Underwriter through you, specifically for use in the preparation of such document, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 6(f).

Each reference to an “ issuer free writing prospectus ” herein means an issuer free writing prospectus as defined in Rule 433 of the Rules and Regulations.

“ Time of Sale Disclosure Package ” means the Preliminary Prospectus, dated May 22 , 2018, any free writing prospectus set forth on Schedule II and the information on Schedule III, all considered together.

Each reference to a “ free writing prospectus ” herein means a free writing prospectus as defined in Rule 405 of the Rules and Regulations.

“ Time of Sale ” means 8:12 a.m. (Eastern Time) on the date of this Agreement.

(A) Each issuer free writing prospectus, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Securities or until any earlier date that the Company notified or notifies the Representatives as described in Section 4(a)(iii)(B), did not, does not and will not include any information that conflicts, within the meaning of Rule 433(c) under the Act, with the information contained in the Registration Statement, any Preliminary Prospectus or the Prospectus. The foregoing sentence does not apply to statements in or omissions from any issuer free writing prospectus based upon and in conformity with written information furnished to the Company by you or by any Underwriter through you specifically for use therein; it being understood and agreed that the only such information furnished by or on behalf of any Underwriter consists of the information described as such in Section 6(f).

(B) At the time of filing the Registration Statement, including any post-effective amendment thereto, and at the date hereof, the Company was not and is not an “ineligible issuer,” as defined in Rule 405 of the Rules and Regulations, without taking account of any determination by the Commission pursuant to Rule 405 of the Rules and Regulations that it is not necessary that the Company be considered an ineligible issuer.

(C) Each issuer free writing prospectus satisfied, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Securities, all other conditions to use thereof as set forth in Rules 164 and 433 under the Act.

(iv) Emerging Growth Company . From the time of the initial filing of the Registration Statement to the Commission through the date hereof, the Company has been and is an “emerging growth company,” as defined in Section 2(a) of the Act (an “ Emerging Growth Company ”).

(vi) No Other Offering Materials . The Company has not distributed and will not distribute any prospectus or other offering material in connection with the offering and sale of the Securities other than any Preliminary Prospectus, the Time of Sale Disclosure Package or the Prospectus or other materials permitted by the Act to be distributed by the Company; provided, however, that, except as set forth on Schedule II, the Company has not made and will not make any offer relating to the Securities that would constitute a free writing prospectus, except in accordance with the provisions of Section 4(a)(xiii) of this Agreement.

(vii) Financial Statements . The financial statements of the Company and its subsidiaries, together with the related notes, set forth or incorporated by reference in the Registration Statement, the Time of Sale Disclosure Package and Prospectus comply in all material respects with the requirements of Regulation S-X under the Act and fairly present the financial condition of the Company and its consolidated subsidiaries 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 in the United States consistently applied throughout the periods involved; the supporting schedules included or incorporated by reference in the Registration Statement present fairly the information required to be stated therein; and, except as disclosed in the Time of Sale Disclosure Package and the Prospectus, there are no material off-balance sheet arrangements (as defined in Regulation S-K under the Act, Item 303(a)(4)(ii)) or any other relationships with unconsolidated entities or other persons, that would reasonably be expected to have a material current or, to the Company’s knowledge, material future effect on the Company’s financial condition, results of operations, liquidity, capital expenditures, capital resources or significant components of revenue or expenses. No other financial statements or schedules are required to be included or incorporated by reference in the Registration Statement, the Time of Sale Disclosure Package or the Prospectus. Each of Haskell & White LLP and KPMG LLP, who has expressed its opinion with respect to the financial statements and schedules filed as a part of the Registration Statement and included in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, is (x) an independent public accounting firm within the meaning of the Act and the Rules and Regulations, (y) a registered public accounting firm (as defined in Section 2(a)(12) of the Sarbanes-Oxley Act of 2002 (the “ Sarbanes-Oxley Act ”)) and (z) not in violation of the auditor independence requirements of the Sarbanes-Oxley Act. The interactive data in eXtensbile Business Reporting Language incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus 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.

(viii) Organization and Good Standing . Each of the Company and its subsidiaries has been duly organized and is validly existing as a corporation in good standing under the laws of its jurisdiction of incorporation. Each of the Company and its subsidiaries 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 Disclosure Package and 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 and its subsidiaries, taken as a whole (“ Material Adverse Effect ”).

(ix) Absence of Certain Events . Except as contemplated or disclosed in the Time of Sale Disclosure Package and in the Prospectus, subsequent to the respective dates as of which information is given in the Time of Sale Disclosure Package,

neither the Company nor any of its subsidiaries has 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 its capital stock; and there has not been any change in the capital stock (other than a change in the number of outstanding shares of Common Stock due to the issuance of shares pursuant to the Company’s employee stock purchase plan or upon the exercise of outstanding options or warrants or conversion of convertible securities), or any material change in the short-term or long-term debt (other than as a result of the conversion of convertible securities), or any issuance of options (other than as a result of option issuances in the ordinary course of business), warrants, convertible securities or other rights to purchase the capital stock, of the Company or any of its subsidiaries, or any material adverse change in the general affairs, condition (financial or otherwise), business, prospects, management, properties, operations or results of operations of the Company and its subsidiaries, taken as a whole (“ Material Adverse Change ”) or any development which would reasonably be expected to result in any Material Adverse Change.

(x) Absence of Proceedings . Except as set forth in the Time of Sale Disclosure Package and in the Prospectus, there is not pending or, to the knowledge of the Company, threatened or contemplated, any action, suit or proceeding (a) to which the Company or any of its subsidiaries is a party or (b) which has as the subject thereof any officer or director of the Company or any subsidiary, any employee benefit plan sponsored by the Company or any subsidiary or any property or assets owned or leased by the Company or any subsidiary before or by any court or Governmental Authority (as defined below), or any arbitrator, which, individually or in the aggregate, would result in any Material Adverse Change, or would materially and adversely affect the ability of the Company to perform its obligations under this Agreement. There are no current or, to the knowledge of the Company, pending, legal, governmental or regulatory actions, suits or proceedings (x) to which the Company or any of its subsidiaries is subject or (y) which has as the subject thereof any officer or director of the Company (in their capacity as such or, to the Company’s knowledge, other than in their capacity as such) or any subsidiary, any employee plan sponsored by the Company or any subsidiary or any property or assets owned or leased by the Company or any subsidiary, that are required to be described in the Registration Statement, Time of Sale Disclosure Package and Prospectus by the Act or by the Rules and Regulations and that have not been so described.

(xi) Authorization; No Conflicts; Authority . This Agreement has been duly authorized, executed and delivered by the Company, and constitutes a valid, legal and binding obligation of the Company, enforceable in accordance with its terms, except as rights to indemnity hereunder may be limited by federal or state securities laws and except as such enforceability may be limited by bankruptcy, insolvency, reorganization or similar laws affecting the rights of creditors generally and subject to general principles of equity. The execution, delivery and performance of this Agreement and the consummation of the transactions herein contemplated will not (A) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries pursuant to any indenture, mortgage, deed of trust, loan agreement

or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, (B) result in any violation of the provisions of the Company’s charter or by-laws or (C) result in the violation of any law or statute or any judgment, order, rule, regulation or decree of any court or arbitrator or federal, state, local or foreign governmental agency or regulatory authority having jurisdiction over the Company or any of its subsidiaries or any of their properties or assets (each, a “ Governmental Authority ”), except in the case of clause (A) as would not result in a Material Adverse Effect. No consent, approval, authorization or order of, or registration or filing with any Governmental Authority is required for the execution, delivery and performance of this Agreement or for the consummation of the transactions contemplated hereby, including the issuance or sale of the Securities by the Company, except such as may be required under the Act, the rules of the Financial Industry Regulatory Authority (“ FINRA ”) or state securities or blue sky laws; and the Company has full power and authority to enter into this Agreement and to consummate the transactions contemplated hereby, including the authorization, issuance and sale of the Securities as contemplated by this Agreement.

(xii) Capitalization; the Securities; Registration Rights . All of the issued and outstanding shares of capital stock of the Company, including the outstanding shares of Common Stock, are duly authorized and validly issued, fully paid and nonassessable, have been issued in compliance with all federal and state and foreign securities laws, were not issued in violation of or subject to any preemptive rights or other rights to subscribe for or purchase securities that have not been waived in writing (a copy of which has been delivered to counsel to the Representatives), and the holders thereof are not subject to personal liability by reason of being such holders; the Securities which may be sold hereunder by the Company 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 Common Stock (including the Securities), conforms in all material respects to the description thereof in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus. Except as otherwise stated in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus, (A) 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 of Common Stock pursuant to the Company’s charter, by-laws or any agreement or other instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound, and (B) neither the filing of the Registration Statement nor the offering or sale of the Securities as contemplated by this Agreement gives rise to any rights for or relating to the registration of any shares of Common Stock or other securities of the Company. All of the issued and outstanding shares of capital stock of each of the Company’s subsidiaries have been duly and validly authorized and issued and are fully paid and nonassessable, and, except as otherwise described in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus, the Company owns of record and beneficially, free and clear of any security interests, claims, liens, proxies, equities or other encumbrances, all of the issued and

outstanding shares of such stock. The Company has not sold or issued any securities that would be integrated with the offering of Common Stock contemplated by this Agreement pursuant to the Act, the rules and regulations thereunder or the interpretations thereof by the Commission. The Company has an authorized and outstanding capitalization as set forth in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus under the caption “Capitalization.” The Common Stock (including the Securities) conforms in all material respects to the description thereof contained in the Time of Sale Disclosure Package and the Prospectus. The issue and sale of the Common Stock, the execution, delivery and performance of this Agreement by the Company, the consummation of the transactions contemplated hereby and the application of the proceeds from the sale of the Securities as described under “Use of Proceeds” in the most recent Preliminary Prospectus will not (i) conflict with or result in a breach or violation of any of the terms or provisions of, impose any lien, charge or encumbrance upon any property or assets of the Company and its subsidiaries, or constitute a default under, any indenture, mortgage, deed of trust, loan agreement, license, lease or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject; (ii) result in any violation of the provisions of the charter or by-laws (or similar organizational documents) of the Company or any of its subsidiaries; or (iii) result in any violation of any statute or any judgment, order, decree, rule or regulation of any court or governmental agency or body having jurisdiction over the Company or any of its subsidiaries or any of their properties or assets.

(xiii) Stock Options . Except as described in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus or otherwise issued in the ordinary course of business pursuant to the Company Stock Plans (as defined below), there are no options, warrants, agreements, contracts or other rights in existence to purchase or acquire from the Company or any subsidiary of the Company any shares of the capital stock of the Company or any subsidiary of the Company. The description of the Company’s stock option, stock bonus and other stock plans or arrangements (the “ Company Stock Plans ”), and the options (the “ Options ”) or other rights granted thereunder, set forth in the Time of Sale Disclosure Package and the Prospectus accurately and fairly presents the information required to be shown with respect to such plans, arrangements, options and rights. Each grant of an Option (A) was duly authorized no later than the date on which the grant of such Option was by its terms to be effective by all necessary corporate action, including, as applicable, approval by the board of directors of the Company (or a duly constituted and authorized committee thereof) and any required stockholder approval by the necessary number of votes or written consents, and the award agreement governing such grant (if any) was duly executed and delivered by each party thereto and (B) was made in accordance with the terms of the applicable Company Stock Plan, and all applicable laws and regulatory rules or requirements, including all applicable federal securities laws, except, in each case, as has been subsequently remedied or as would not materially impact the Company’s capitalization or ability to consummate the offering.

(xiv) Permits; Compliance with Laws . The Company and each of its subsidiaries holds, and is operating in compliance in all material respects with, all

franchises, grants, authorizations, licenses, permits, easements, consents, certificates, exemptions, approvals, clearances and orders of any Governmental Authority or self-regulatory body required for the conduct of its business (collectively, “ Permits ”) and all such Permits are valid and in full force and effect, except as would not result in a Material Adverse Effect; and neither the Company nor any of its subsidiaries has received notice of any revocation or modification of any such Permit or has reason to believe that any such Permit will not be renewed in the ordinary course; and the Company and each of its subsidiaries is in compliance in all material respects with all applicable federal, state, local and foreign laws, regulations, orders and decrees.

(xv) Ownership of Assets . The Company and its subsidiaries have good and marketable title to all property (whether real or personal) described in the Registration Statement, in the Time of Sale Disclosure Package and in 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 not material to the Company or are described in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus. The property held under lease by the Company and 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.

(xvi) Intellectual Property . Except as described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, the Company and each of its subsidiaries owns, possesses, has a valid and enforceable license for or other rights to use on reasonable terms, all Intellectual Property described in the Registration Statement, the Pricing Disclosure Package and the Prospectus as being owned or licensed by them. To the Company’s knowledge, the Company and each of its subsidiaries owns, possesses, has a valid and enforceable license for or other rights to use on reasonable terms, all Intellectual Property necessary for the conduct of the Company’s and its subsidiaries’ business as now conducted or as described in the Registration Statement, the Time of Sale Disclosure Package 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 Intellectual Property described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus as being owned by or exclusively licensed to the Company or any of its subsidiaries; (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 any of 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 and 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 any of its subsidiaries infringes, misappropriates or otherwise violates any Intellectual Property or other proprietary rights of others, or would, upon the commercialization of any product candidate or service described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, infringe, misappropriate or otherwise violate any such Intellectual Property, neither the Company or any of its subsidiaries has received any written notice of any 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 Company’s knowledge, none of the technology employed by the Company or any of its subsidiaries has been obtained or is being used by the Company or any subsidiary in violation of any contractual obligation binding on the Company or any subsidiary, to the Company’s knowledge, upon any of its or their officers, directors or employees, and the Company is not aware of any facts that it believes would form a reasonable basis for a successful challenge, and, to the knowledge of the Company, no employee of the Company or any of 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 any of its subsidiaries or actions undertaken by the employee while employed with the Company or any of its subsidiaries, except as such violation would not result in a Material Adverse Effect. To the Company’s knowledge, there is no patent or patent application that contains claims that dominate, may dominate or interfere (as such term is described in 35 U.S.C. §135 and 37 C.F.R. 41.100 to 41.208) with the issued or pending claims of any of the Intellectual Property owned by or exclusively licensed to the Company or any of its subsidiaries; and to the Company’s knowledge, there is no prior art material to any patent or patent application of the Intellectual Property owned by or exclusively licensed to the Company or any of its subsidiaries that may render any U.S. patent owned by or exclusively licensed to the Company or any of its subsidiaries invalid or any U.S. patent application owned by or exclusively licensed to the Company or any of its subsidiaries unpatentable that has not been disclosed to the U.S. Patent and Trademark Office. “ Intellectual Property ” shall mean all patents, patent applications, trade and service marks, trade and service mark registrations, trade names, copyrights, licenses, inventions, know-how (including trade secrets and other unpatented and/or unpatentable proprietary information), software, domain names, technology, know-how and other intellectual property rights, including registrations and applications for registration thereof.

(xvii) No Violations or Defaults . Neither the Company nor any of its subsidiaries is in violation of its respective charter, by-laws or other organizational documents, or 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, loan agreement 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 or any of its subsidiaries is subject. The statements made in the Time of Sale Disclosure Package or in the Prospectus, insofar as they purport to constitute summaries of the terms of the contracts and other documents described and filed, constitute

accurate summaries of the terms of such contracts and documents in all material respects. Neither the Company nor any of its subsidiaries has knowledge that any other party to any such contract or other document has any intention not to render full performance as contemplated by the terms thereof.

(xviii) Taxes . The Company and its subsidiaries have timely filed all federal, state, local and foreign tax returns required to be filed and are not in default in the payment of any material taxes which were payable pursuant to said returns or any assessments with respect thereto, other than any which the Company or any of its subsidiaries is 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 any of its subsidiaries for which there is not an adequate reserve reflected in the Company’s financial statements included in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus.

(xix) Exchange Listing and Exchange Act Registration . The Securities have been approved for listing on the NYSE American and registered under Section 12(b) of the Exchange Act. Except as previously disclosed to counsel for the Underwriters or as set forth in the Registration Statement, Time of Sale Disclosure Package and the Prospectus, there are no affiliations with members of FINRA among the Company’s officers or directors or, to the knowledge of the Company, any five percent or greater stockholders of the Company or any beneficial owner of the Company’s unregistered equity securities that were acquired during the 90-day period immediately preceding the initial filing date of the Registration Statement.

(xx) Ownership of Other Entities . The Company owns no capital stock or other equity or ownership or proprietary interest in any corporation, partnership, association, trust or other entity.

(xxi) Internal Controls . The Company and its subsidiaries maintain a system of internal accounting controls over financial reporting (as such term is defined in Rule 13a-15(f) of the Exchange Act) that complies with the applicable requirements of the Exchange Act and that has been designed by, or under the supervision of, the Company’s principal executive and principal financial officers, sufficient to provide reasonable assurances 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 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 disclosed in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus, the Company’s internal control over financial reporting is effective and none of the Company, its board of directors and audit committee is aware of any “significant deficiencies” or “material weaknesses” (each as defined by the Public Company Accounting

Oversight Board) in its internal control over financial reporting, or any fraud, whether or not material, that involves management or other employees of the Company or its subsidiaries who have a significant role in the Company’s internal controls; and since the end of the latest audited fiscal year, there has been no change in the Company’s internal control over financial reporting (whether or not remediated) that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting. The Company’s board of directors has, subject to the exceptions, cure periods and the phase-in periods specified in the applicable stock exchange rules (“ Exchange Rules ”), validly appointed an audit committee to oversee internal accounting controls whose composition satisfies the applicable requirements of the Exchange Rules and the Company’s board of directors and/or the audit committee has adopted a charter that satisfies the requirements of the Exchange Rules. The section entitled “Management’s Discussion and Analysis of Financial Condition and Results of Operations – Critical Accounting Policies” set forth or incorporated by reference in the most recent Preliminary Prospectus accurately and fully describes (i) the accounting policies that the Company believes are the most important in the portrayal of the Company’s financial condition and results of operations and that require management’s most difficult, subjective or complex judgments (“ Critical Accounting Policies ”); (ii) the judgments and uncertainties affecting the application of Critical Accounting Policies; and (iii) the likelihood that materially different amounts would be reported under different conditions or using different assumptions and an explanation thereof.

(xxii) No Brokers or Finders . Other than as contemplated by this Agreement, the Company has not incurred and will not incur any liability for any finder’s or broker’s fee or agent’s commission in connection with the execution and delivery of this Agreement or the consummation of the transactions contemplated hereby.

(xxiii) Insurance . The Company and each of its subsidiaries carries, or is covered by, insurance from reputable insurers in such amounts and covering such risks as is, based on companies engaged in similar businesses in similar industries, adequate for the conduct of its business and the value of its properties and the properties of its subsidiaries 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 or any of its subsidiaries or its business, assets, employees, officers and directors are in full force and effect; the Company and its subsidiaries are in compliance with the terms of such policies and instruments in all material respects; there are no claims by the Company or any of 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; neither the Company nor any of its subsidiaries has been refused any insurance coverage sought or applied for; and neither the Company nor any of its subsidiaries has reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business at a cost that would not have a Material Adverse Effect.

(xxiv) Investment Company Act . The Company is not and, after giving effect to the offering and sale of the Securities, will not be an “investment company,” as such term is defined in the Investment Company Act of 1940, as amended.

(xxv) Sarbanes-Oxley Act . The Company is in compliance with all applicable provisions of the Sarbanes-Oxley Act and the rules and regulations of the Commission thereunder.

(xxvi) Disclosure Controls . The Company has established and maintains disclosure controls and procedures (as defined in Rule 13a-15(e) under the Exchange Act) and such controls and procedures are effective in ensuring that material information relating to the Company, including its subsidiaries, 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, in the Time of Sale Disclosure Package and in the Prospectus.

(xxvii) Anti-Bribery and Anti-Money Laundering Laws . Each of the Company, its subsidiaries, its affiliates and, to the knowledge of the Company, any of their respective officers, directors, supervisors, managers, agents, or employees, has not violated, its participation in the offering will not violate, and the Company and each of its subsidiaries has instituted and maintains policies and procedures designed to ensure continued compliance with, each of the following laws: (A) anti-bribery laws, including but not limited to, any applicable law, rule, or regulation of any locality, including but not limited to any law, rule, or regulation promulgated to implement the OECD Convention on Combating Bribery of Foreign Public Officials in International Business Transactions, signed December 17, 1997, including the U.S. Foreign Corrupt Practices Act of 1977, as amended, the U.K. Bribery Act 2010, or any other law, rule or regulation of similar purposes and scope or (B) anti-money laundering laws, including but not limited to, applicable federal, state, international, foreign or other laws, regulations or government guidance regarding anti-money laundering, including, without limitation, Title 18 US. Code section 1956 and 1957, the Patriot Act, the Bank Secrecy Act, and international anti-money laundering principles or procedures by an intergovernmental group or organization, such as the Financial Action Task Force on Money Laundering, of which the United States is a member and with which designation the United States representative to the group or organization continues to concur, all as amended, and any Executive order, directive, or regulation pursuant to the authority of any of the foregoing, or any orders or licenses issued thereunder (the “ Money Laundering Laws ”).

(A) Neither the Company nor any of its subsidiaries, nor, to the Company’s knowledge, any of their directors, officers or employees, agents, affiliate or representative of the Company or its subsidiaries, is an individual or entity that is, or is owned or controlled by an individual or entity that is:

(1) the subject of any sanctions administered or enforced by the U.S. Department of Treasury’s Office of Foreign Assets Control, the United Nations Security Council, the European Union, Her Majesty’s Treasury, or other relevant sanctions authority (collectively, “ Sanctions ”), nor

(2) located, organized or resident in a country or territory that is the subject of Sanctions (including, without limitation, Crimea, Cuba, Iran, North Korea, Sudan and Syria).

(B) Neither the Company nor any of its subsidiaries will, directly or indirectly, use the proceeds of the offering, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other individual or entity:

(1) to fund or facilitate any activities or business of or with any individual or entity or in any country or territory that, at the time of such funding or facilitation, is the subject of Sanctions; or

(2) in any other manner that will result in a violation of Sanctions by any individual or entity (including any individual or entity participating in the offering, whether as underwriter, advisor, investor or otherwise).

(C) For the past five years, neither the Company nor any of its subsidiaries has knowingly engaged in, and is not now knowingly engaged in, any dealings or transactions with any individual or entity, or in any country or territory, that at the time of the dealing or transaction is or was the subject of Sanctions.

(xxix) Compliance with Environmental Laws . Except as disclosed in the Time of Disclosure Package and the Prospectus, neither the Company nor any of its subsidiaries is in violation of any statute, any rule, regulation, decision or order of any Governmental Authority or any court, domestic or foreign, relating to the use, disposal or release of hazardous or toxic substances or relating to the protection or restoration of the environment or human exposure to hazardous or toxic substances (collectively, “ Environmental Laws ”), owns or operates any real property contaminated with any substance that is subject to any Environmental Laws, is liable for any off-site disposal or contamination pursuant to any Environmental Laws, or is subject to any claim relating to any Environmental Laws, which violation, contamination, liability or claim would individually or in the aggregate, have a Material Adverse Effect; and the Company is not aware of any pending investigation which would reasonably be expected to lead to such a claim. Neither the Company nor any of its subsidiaries anticipates incurring any material capital expenditures relating to compliance with Environmental Laws.

(xxx) Compliance with Occupational Laws . The Company and each of its subsidiaries (A) is in compliance, in all 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 ”), except as would not result in a Material Adverse Effect; (B) has received all material permits, licenses or other approvals required of it under applicable Occupational Laws to conduct its business as currently conducted; and (C) is 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.

(xxxi) ERISA and Employee Benefits Matters . (A) To the knowledge of the Company, no “prohibited transaction” as defined under Section 406 of ERISA or Section 4975 of the Code and not exempt under ERISA Section 408 and the regulations and published interpretations thereunder has occurred with respect to any Employee Benefit Plan. At no time has the Company or any ERISA Affiliate maintained, sponsored, participated in, contributed to or has or had any liability or obligation in respect of any Employee Benefit Plan subject to Part 3 of Subtitle B of Title I of ERISA, Title IV of ERISA, or Section 412 of the Code or any “multiemployer plan” as defined in Section 3(37) of ERISA or any multiple employer plan for which the Company or any ERISA Affiliate has incurred or would reasonably be expected to incur liability under Section 4063 or 4064 of ERISA. No Employee Benefit Plan provides or promises, or at any time provided or promised, retiree health, life insurance, or other retiree welfare benefits except as may be required by the Consolidated Omnibus Budget Reconciliation Act of 1985, as amended, or similar state law. Each Employee Benefit Plan is and has been operated in material compliance with its terms and all applicable laws, including but not limited to ERISA and the Code and, to the knowledge of the Company, no event has occurred (including a “reportable event” as such term is defined in Section 4043 of ERISA) and no condition exists that would subject the Company or any ERISA Affiliate to any material tax, fine, lien, penalty or liability imposed by ERISA, the Code or other applicable law. Each Employee Benefit Plan intended to be qualified under Code Section 401(a) is so qualified and has a favorable determination or opinion letter from the IRS upon which it can rely, and any such determination or opinion letter remains in effect and has not been revoked; to the knowledge of the Company, nothing has occurred since the date of any such determination or opinion letter that is reasonably likely to adversely affect such qualification; (B) with respect to each Foreign Benefit Plan, such Foreign Benefit Plan (1) if intended to qualify for special tax treatment, meets, in all material respects, the requirements for such treatment, and (2) if required to be funded, is funded to the extent required by applicable law, and with respect to all other Foreign Benefit Plans, adequate reserves therefor have been established on the accounting statements of the applicable Company or subsidiary; (C) the Company does not have any obligations

under any collective bargaining agreement with any union and no organization efforts are underway with respect to Company employees. As used in this Agreement, “ Code ” means the Internal Revenue Code of 1986, as amended; “ Employee Benefit Plan ” means any “employee benefit plan” within the meaning of Section 3(3) of ERISA, including, without limitation, all stock purchase, stock option, stock-based severance, employment, change-in-control, medical, disability, fringe benefit, bonus, incentive, deferred compensation, employee loan and all other employee benefit plans, agreements, programs, policies or other arrangements, whether or not subject to ERISA, under which (x) any current or former employee, director or independent contractor of the Company or its subsidiaries has any present or future right to benefits and which are contributed to, sponsored by or maintained by the Company or any of its respective subsidiaries or (y) the Company or any of its subsidiaries has had or has any present or future obligation or liability; “ ERISA ” means the Employee Retirement Income Security Act of 1974, as amended; “ ERISA Affiliate ” means any member of the company’s controlled group as defined in Code Section 414(b), (c), (m) or (o); and “ Foreign Benefit Plan ” means any Employee Benefit Plan established, maintained or contributed to outside of the United States of America or which covers any employee working or residing outside of the United States.

(xxxii) Business Arrangements . Except as disclosed in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, neither the Company nor any of its subsidiaries has granted rights to develop, manufacture, produce, assemble, distribute, license, market or sell its products to any other person and is not bound by any agreement that affects the exclusive right of the Company or such subsidiary to develop, manufacture, produce, assemble, distribute, license, market or sell its future products, if approved.

(xxxiii) Labor Matters . No labor problem or dispute with the employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is threatened or imminent, and the Company is not aware of any existing or imminent labor disturbance by the employees of any of its or its subsidiaries’ principal suppliers, contractors or customers, that would reasonably be expected to have a Material Adverse Effect. Neither the Company nor any subsidiary is in violation of or has received notice of any violation with respect to any federal or state law relating to discrimination in the hiring, promotion or pay of employees, nor any applicable federal or state wage and hour laws, nor any state law precluding the denial of credit due to the neighborhood in which a property is situated, the violation of any of which could reasonably be expected to have a Material Adverse Effect.

(xxxiv) Restrictions on Subsidiary Payments to the Company . No subsidiary of the Company is currently prohibited, directly or indirectly, from paying any dividends to the Company, from making any other distribution on such subsidiary’s capital stock, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s property or assets to the Company or any other subsidiary of the Company, except as described in or contemplated by the Time of Sale Disclosure Package and the Prospectus.

(xxxv) Disclosure of Legal Matters . There are no statutes, regulations, legal or governmental proceedings or contracts or other documents required to be described in the Time of Sale Disclosure Package or in the Prospectus or included as exhibits to the Registration Statement that are not described or included as required.

(xxxvi) Statistical Information . Any third-party statistical and market-related data included or incorporated by reference in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus are based on or derived from sources that the Company believes to be reliable and accurate in all material respects.

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

(xxxviii) Compliance with Healthcare Laws . The Company and each of its subsidiaries and, to the Company’s knowledge, its directors, officers, employees, and agents (while acting in such capacity) are, and at all times since January 1, 2015 have been, in material compliance with, all healthcare laws applicable to the Company and each of its subsidiaries or any of its products or activities, including, but not limited to, the federal Anti-Kickback Statute (42 U.S.C. § 1320a-7b(b)), the civil False Claims Act (31 U.S.C. §§ 3729 et seq.), the criminal False Claims Law (42 U.S.C. § 1320a-7b(a)), the federal Physician Payment Sunshine Act (42 U.S.C. Section 1320a-7h), the Civil Monetary Penalties Law (42 U.S.C. § 1320a-7a), the Health Insurance Portability and Accountability Act of 1996 (42 U.S.C. § 1320d et seq.), as amended by the Health Information Technology for Economic and Clinical Health Act (42 U.S.C. §§ 17921 et seq, the exclusion laws (42 U.S.C. § 1320a-7), the Federal Food, Drug, and Cosmetic Act, the Controlled Substances Act, the Public Health Service Act, Medicare (Title XVIII of the Social Security Act), Medicaid (Title XIX of the Social Security Act), the regulations promulgated pursuant to such laws, and any other state or federal law, accreditation standards, regulation, memorandum, opinion letter, or other issuance which imposes requirements on the manufacturing, development, testing, labeling, marketing or distribution of pharmaceutical products, kickbacks, patient or program charges, recordkeeping, claims process, documentation requirements, medical necessity, referrals, the hiring of employees or acquisition of services or supplies from those who have been excluded from government health care programs, quality, safety, privacy, security, licensure, accreditation or any other aspect of providing health care or pharmaceutical services (collectively, “ Healthcare Laws ”), and have not engaged in activities which are, as applicable, prohibited or cause for false claims liability, civil penalties, or mandatory or permissive exclusion from Medicare, Medicaid or any other state or federal health care program. The Company has not received any notification, correspondence or any other written or oral communication, including notification of any pending or threatened claim, suit, proceeding, hearing, enforcement, investigation, arbitration or other action from any governmental authority, including, without limitation, the United States Food and Drug

Administration (“ FDA ”), the Drug Enforcement Administration (“ DEA ”), the Centers for Medicare & Medicaid Services, the U.S. Department of Justice, or the U.S. Department of Health and Human Services Office of Inspector General, of potential or actual non-compliance by, or liability of, the Company or any of its subsidiaries under any Health Care Laws. To the Company’s knowledge, there are no facts or circumstances that would reasonably be expected to give rise to liability of the Company or any of its subsidiaries under any Healthcare Laws.

(xxxiv) Permits . The Company and, as applicable, each of its subsidiaries holds all material, and is operating in material compliance with, such Permits of the FDA and other governmental authorities required for the conduct of its business as currently conducted, and all such Permits are in full force and effect. The Company and each of its subsidiaries have fulfilled and performed all of their material obligations with respect to the Permits, and, to the Company’s knowledge, no event has occurred which allows, or after notice or lapse of time would allow, revocation or termination thereof or results in any other material impairment of the rights of the holder of any Permit. To the Company’s knowledge, all applications, notifications, submissions, information, claims, reports and statistics, and other data and conclusions derived therefrom, utilized as the basis for any and all requests for a Permit from the FDA or other governmental authority relating to the Company and its subsidiaries, their business and the product candidates of the Company, when submitted to the FDA or other governmental authority, were true, complete and correct in all material respects as of the date of submission and any necessary or required updates, changes, corrections or modification to such applications, submissions, information and data have been submitted to the FDA or other governmental authority.

(xxxv) Manufacturing Practice . The manufacture of Company product candidates by or on behalf of the Company is being conducted in compliance in all material respects with all applicable Healthcare Laws, including, without limitation, the FDA’s current good manufacturing practice regulations for products sold in the United States, and the respective counterparts thereof promulgated by governmental authorities in countries outside the United States.

(xxxvi) Regulatory Enforcement . Except as disclosed in the Time of Sale Disclosure Package and the Prospectus or as would not reasonably be expected to have a Material Adverse Effect, since January 1, 2015, the Company and its subsidiaries have not had any product or manufacturing site (whether Company-owned, Company subsidiary-owned or that of a contract manufacturer for Company product candidates) subject to a governmental authority (including the FDA) shutdown or import or export prohibition, nor received any FDA Form 483 or other governmental authority notice of inspectional observations, “warning letters,” “untitled letters,” requests to make changes to the Company product candidates, processes or operations, or similar correspondence or notice from the FDA or other governmental authority alleging or asserting material noncompliance with any applicable Healthcare Laws. To the Company’s knowledge, neither the FDA nor any other governmental authority is considering such action.

(xxxvii) No Safety Notices . Except as would not reasonably be expected to have a Material Adverse Effect, (i) there have been no recalls, field notifications, field corrections, market withdrawals or replacements, warnings, “dear doctor” letters, investigator notices, safety alerts or other notice of action relating to an alleged lack of safety, efficacy, or regulatory compliance of the Company’s product candidates (collectively, “ Safety Notices ”) since January 1, 2015, (ii) such Safety Notices, if any, were resolved or closed, and (iii) to the Company’s knowledge, there are no material complaints with respect to the Company product candidates that are currently unresolved. To the Company’s knowledge, there are no facts that would be reasonably likely to result in (i) a material Safety Notice with respect to the Company product candidates, (ii) a material change in labeling of any the Company’s product candidates, or (iii) a termination or suspension of marketing or testing of any of the Company product candidates.

(xxxviii) Clinical Studies . The clinical and pre-clinical studies and tests conducted by or on behalf of or sponsored by the Company or any of its subsidiaries, were, and if still pending, are, being conducted in all material respects in accordance with all applicable Healthcare Laws, including, but not limited to, the Federal Food, Drug and Cosmetic Act and its applicable implementing regulations at 21 C.F.R. Parts 50, 54, 56, 58, and 312. Any descriptions of clinical, pre-clinical and other studies and tests, including any related results and regulatory status, contained in the Registration Statement, the Time of Sale Disclosure Package or the Prospectus are accurate and complete in all material respects. Except as disclosed in the Time of Sale Disclosure Package and the Prospectus, there are no studies, tests or trials the result of which reasonably call into question in any material respect the clinical trial results described or referred to in the Registration Statement, the Time of Sale Disclosure Package or the Prospectus. No investigational new drug application filed by or on behalf of the Company or any of its subsidiaries with the FDA has been terminated or suspended by the FDA, and neither the FDA nor any applicable foreign regulatory agency has commenced, or, to the Company’s knowledge, threatened to initiate, any action to place a clinical hold order on, or otherwise terminate, delay or suspend, any proposed or ongoing clinical investigation conducted or proposed to be conducted by or on behalf of the Company or any of its subsidiaries.

(xxxix) No Corporate Integrity Agreements . The Company, or any of its subsidiaries, is not a party to or has any ongoing reporting obligations pursuant to any corporate integrity agreements, monitoring agreements, deferred prosecution agreements, consent decrees, settlement orders, or similar agreements with or imposed by any governmental authority.

(xl) No Debarments . Neither the Company nor any of its directors, officers, employees, or, to the Company’s knowledge, agents, is debarred or excluded, or has been convicted of any crime or engaged in any conduct that could result in a debarment or exclusion, from any federal or state government health care program under 21 U.S.C. § 335a or any similar state law, rule or regulation. As of the effective date of the Registration Statement, no claims, actions, proceedings or investigations that

would reasonably be expected to result in such a debarment or exclusion are pending or, to the Company’s knowledge, threatened against the Company or any of its subsidiaries, or the directors, officers, employees or agents of the Company or any of its subsidiaries.

(xli) No Relationships . Except as disclosed in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, no relationship, direct or indirect, exists between or among the Company, on the one hand, and the directors, officers, stockholders, customers or suppliers of the Company, on the other hand, that is required to be described in the most recent Preliminary Prospectus which is not so described.

(xlii) Beneficial Owners . The Company satisfies the conditions set forth in 31 CFR § 1010.230(e)(2)(iii) and is therefore not a “legal entity customer” within the meaning of such section.

(b) Effect of Certificates . Any certificate signed by any officer of the Company and delivered to you or to counsel for the Underwriters shall be deemed a representation and warranty by the Company to each Underwriter as to the matters covered thereby.

(a) Firm Shares . On the basis of the representations, warranties and agreements herein contained, but subject to the terms and conditions herein set forth, the Company agrees to issue and sell 6,800,000 Firm Shares to the several Underwriters, and each Underwriter agrees, severally and not jointly, to purchase from the Company the number of Firm Shares set forth opposite the name of such Underwriter in Schedule I hereto. The purchase price for each Firm Share shall be $5.115 per share. In making this Agreement, each Underwriter is contracting severally and not jointly; except as provided in paragraph (d) of this Section 3 and in Section 8 hereof, the agreement of each Underwriter is to purchase only the respective number of Firm Shares specified in Schedule I.

(b) Option Shares . On the basis of the representations, warranties and agreements herein contained, but subject to the terms and conditions herein set forth, the Company grants to the Underwriters an option to purchase up to 1,020,000 Option Shares, severally and not jointly, at the same purchase price as the Firm Shares. The option granted hereunder may be exercised in whole or in part at any time within 30 days after the effective date of this Agreement upon notice (confirmed in writing) by the Representatives to the Company setting forth the aggregate number of Option Shares as to which the several Underwriters are exercising the option and the date and time, as determined by you, when the Option Shares are to be delivered, but in no event earlier than the First Closing Date (as defined below) nor earlier than the second business day or later than the tenth business day after the date on which the option shall have been exercised. No Option Shares shall be sold and delivered unless the Firm Shares previously have been, or simultaneously are, sold and delivered.

(i) The Securities to be purchased by each Underwriter hereunder, in book-entry form in such authorized denominations and registered in such names as Barclays may request upon at least forty-eight hours’ prior notice to the Company, shall be delivered by or on behalf of the Company to Barclays, through the facilities of DTC, for the account of such Underwriter, with any transfer taxes payable in connection with the transfer of the Securities to the Underwriters duly paid, against payment by or on behalf of such Underwriter of the purchase price therefor by wire transfer of Federal (same-day) funds to the accounts specified by the Company to the Representatives at least forty-eight hours in advance. The time and date of such delivery and payment shall be, with respect to the Firm Shares, 9:00 a.m., New York City time, on May 25, 2018 or such other time and date as the Representatives, the Company may agree upon in writing, and, with respect to the Option Shares, 9:00 a.m., New York City time, on the date specified by the Representatives in each written notice given by the Representatives of the Underwriters’ election to purchase such Option Shares, or such other time and date as the Representatives and the Company may agree upon in writing. Such time and date for delivery of the Firm Shares is herein called the “ First Closing Date ,” each such time and date for delivery of the Option Shares, if not the First Closing Date, is herein called a ” Second Closing Date ,” and each such time and date for delivery is herein called a “ Closing .”

(ii) The documents to be delivered at each Closing by or on behalf of the parties hereto pursuant to Section 5 hereof, including the cross receipt for the Securities and any additional documents requested by the Underwriters pursuant to Section 5(l) hereof, will be delivered at the offices of Latham & Watkins LLP located at 330 North Wabash Avenue, Suite 2800, Chicago, Illinois 60611 (the “ Closing Location ”), and the Securities will be delivered through the facilities of the DTC unless the Representatives otherwise instruct, all at such Closing. A meeting will be held at the Closing Location (or telephonically as mutually agreed by the parties) at 3:00 p.m., New York City time, on the New York Business Day next preceding such Closing, at which meeting the final drafts of the documents to be delivered pursuant to the preceding sentence will be available for review by the parties hereto. For the purposes of this Section 3, “ New York Business Day ” shall mean each Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on which banking institutions in New York City are generally authorized or obligated by law or executive order to close.

(d) Purchase by Representatives on Behalf of Underwriters . It is understood that you, individually and not as Representatives of the several Underwriters, may (but shall not be obligated to) make payment to the Company, on behalf of any Underwriter for the Securities to be purchased by such Underwriter. Any such payment by you shall not relieve any such Underwriter of any of its obligations hereunder. Nothing herein contained shall constitute any of the Underwriters an unincorporated association or partner with the Company.

(a) Covenants of the Company . The Company covenants and agrees with the several Underwriters as follows:

(i) Required Filings . The Company will prepare and file the Prospectus Supplement with the Commission within the time period required by, and otherwise in accordance with the provisions of, Rules 424(b) and Rule 430A, 430B or 430C of the Rules and Regulations; the Company will file any Issuer Free Writing Prospectus to the extent required by Rule 433 under the Securities Act; and the Company will furnish copies of the Prospectus Supplement and each Issuer Free Writing Prospectus (to the extent not previously delivered) to the Underwriters in New York City prior to 10:00 A.M., New York City time, on the business day next succeeding the date of this Agreement in such quantities as the Representatives may reasonably request.

(ii) Notification of Certain Commission Actions . The Company will advise you, promptly after it shall receive notice or obtain knowledge thereof, of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement, including any post-effective amendment thereto, or preventing or suspending the use of any Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus or any issuer free writing prospectus, of the suspension of the qualification of the Securities for offering or sale in any jurisdiction, or of the initiation or threatening of any proceeding for any such purpose; and the Company will promptly use its best efforts to prevent the issuance of any stop order or to obtain its withdrawal if such a stop order should be issued.

(A) Within the time during which a prospectus (assuming the absence of Rule 172) relating to the Securities is required to be delivered under the Act by any Underwriter or dealer, the Company will comply in all material respects with all requirements imposed upon it by the Act, as now and hereafter amended, and by the Rules and Regulations, as from time to time in force, so far as necessary to permit the continuance of sales of or dealings in the Securities as contemplated by the provisions hereof, the Time of Sale Disclosure Package and the Prospectus. If during such period any event occurs as a result of which the Prospectus (or if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package) would include 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 then existing, not misleading, or if during such period it is necessary to amend the Registration Statement or supplement the Prospectus (or if the Prospectus is not yet available to prospective investors, the Time of Sale Disclosure Package) to comply with the Act, the Company promptly will (x) notify you of such untrue statement or omission, (y) amend the Registration Statement or supplement the Prospectus (or, if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package) (at

the expense of the Company) so as to correct such statement or omission or effect such compliance and (z) notify you when any amendment to the Registration Statement is filed or becomes effective or when any supplement to the Prospectus (or, if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package) is filed.

(B) If at any time following issuance of an issuer free writing prospectus there occurred or occurs an event or development as a result of which such issuer free writing prospectus conflicted or would conflict with the information contained in the Registration Statement, any Preliminary Prospectus or the Prospectus relating to the Securities 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 that subsequent time, not misleading, the Company (x) has promptly notified or promptly will notify the Representatives of such conflict, untrue statement or omission, (y) has promptly amended or will promptly amend or supplement, at its own expense, such issuer free writing prospectus to eliminate or correct such conflict, untrue statement or omission and (z) has notified or promptly will notify you when such amendment or supplement was or is filed with the Commission to the extent required to be filed by the Rules and Regulations.

(iv) Blue Sky Qualifications . The Company shall take or cause to be taken all necessary action to qualify the Securities for sale under the securities laws of such domestic United States or foreign jurisdictions as you reasonably designate and to continue such qualifications in effect so long as required for the distribution of the Securities, except that the Company shall not be required in connection therewith to qualify as a foreign corporation or to execute a general consent to service of process in any state.

(v) Provision of Documents . To the extent not available on EDGAR or any successor system, the Company will furnish, at its own expense, to the Underwriters and counsel for the Underwriters copies of the Registration Statement (three of which will be signed and will include all consents and exhibits filed therewith). Further, the Company will furnish, at its own expense, to the Underwriters and any dealer each Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus, any issuer free writing prospectus and all amendments and supplements to such documents, in each case as soon as available and in such quantities as you may from time to time reasonably request.

(vi) Rule 158 . The Company will make generally available to its security holders as soon as practicable, but in no event later than 15 months after the end of the Company’s current fiscal quarter, an earnings statement (which need not be audited) covering a 12-month period beginning after the effective date of the Registration Statement (which, for purposes of this paragraph, will be deemed to be the effective date of the Rule 462(b) Registration Statement, if applicable) that shall satisfy the provisions of Section 11(a) of the Act and Rule 158 of the Rules and Regulations.

(vii) Payment and Reimbursement of Expenses . The Company, whether or not the transactions contemplated hereunder are consummated or this Agreement is terminated, will pay or cause to be paid (A) all expenses (including transfer taxes allocated to the respective transferees) incurred in connection with the delivery to the Underwriters of the Securities, (B) all expenses and fees (including, without limitation, fees and expenses of the Company’s accountants and counsel but, except as otherwise provided below, not including fees of the Underwriters’ counsel) in connection with the preparation, printing, filing, delivery, and shipping of the Registration Statement (including the financial statements therein and all amendments, schedules, and exhibits thereto), the Securities, each Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus, any issuer free writing prospectus and any amendment thereof or supplement thereto, and the printing, delivery, and shipping of this Agreement and other underwriting documents, including Blue Sky Memoranda (covering the states and other applicable jurisdictions), (C) all filing fees and reasonable fees and disbursements of the Underwriters’ counsel incurred in connection with the qualification of the Securities for offering and sale by the Underwriters or by dealers under the securities or blue sky laws of the states and other jurisdictions which you shall designate, (D) the fees and expenses and any transfer agent or registrar, (E) the filing fees and fees and disbursements of Underwriters’ counsel incident to any required review and approval by FINRA of the terms of the sale of the Securities, which fees and disbursements of Underwriters’ counsel shall not exceed $25,000, (F) listing fees, if any, (G) the cost and expenses of the Company relating to investor presentations or any “road show” undertaken in connection with marketing of the Securities, 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 and officers of the Company and any such consultants, and 50% of the cost of any aircraft chartered in connection with the road show and (H) all other costs and expenses of the Company incident to the performance of its obligations hereunder that are not otherwise specifically provided for herein. If this Agreement is terminated by the Representatives pursuant to Section 9 hereof or if the sale of the Securities provided for herein is not consummated by reason of any failure, refusal or inability on the part of the Company to perform any agreement on its part to be performed, or because any other condition of the Underwriters’ obligations hereunder required to be fulfilled by the Company is not fulfilled, the Company will reimburse the several Underwriters for all out-of-pocket accountable disbursements (including but not limited to fees and disbursements of counsel, printing expenses, travel expenses, postage, facsimile and telephone charges) incurred by the Underwriters in connection with their investigation, preparing to market and marketing the Securities or in contemplation of performing their obligations hereunder.

(viii) Use of Proceeds . The Company will apply the net proceeds from the sale of the Securities to be sold by it hereunder for the purposes set forth in the Time of Sale Disclosure Package and in the Prospectus.

(ix) Company Lock Up . The Company will not, without the prior written consent of each of the Representatives, from the date of execution of this

Agreement and continuing to and including the date 90 days after the date of the Prospectus (the “ Lock -Up Period ”), (A) file with the Commission a registration statement under the Act relating to any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock, (B) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock, (C) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (B) or (C) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise, or (D) publicly disclose or announce an intention to effect any transaction specified in clause (A), (B) or (C) above. The restrictions contained in the preceding sentence shall not apply to (V) the shares of Common Stock to be sold hereunder, (W) any shares of Common Stock of the Company issued upon the exercise of options or warrants or the conversion of a security outstanding on the date hereof and described in the Prospectus, (X) the grant of options or the issuance of shares of Common Stock by the Company to employees, officers, directors, advisors or consultants of the Company pursuant to employee benefit plans in effect on the date hereof and described in the Prospectus or (Y) the filing by the Company of a registration statement with the Commission on Form S-8 in respect of any shares issued under or the grant of any award pursuant to an employee benefit plan in effect on the date hereof and described in the Prospectus.

(x) Lock-Up Agreements . The Company has caused to be delivered to you prior to the date of this Agreement a letter, in the form of Exhibit A hereto (the “ Lock -Up Agreement ”), from each director and officers of the Company as agreed upon by the Representatives and the Company. The Company will enforce the terms of each Lock-Up Agreement and issue stop-transfer instructions to its transfer agent and registrar for the Common Stock with respect to any transaction or contemplated transaction that would constitute a breach of or default under the applicable Lock-Up Agreement.

(xi) No Market Stabilization or Manipulation . The Company has not taken and will not take, directly or indirectly, any action designed to or which would reasonably be expected to cause or result in, or which has constituted, the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities, and has not effected any sales of Common Stock which are required to be disclosed in response to Item 701 of Regulation S-K under the Act which have not been so disclosed in the Registration Statement.

(xii) SEC Reports . The Company will file on a timely basis with the Commission such periodic and special reports as required by the Rules and Regulations.

(xiii) Free Writing Prospectuses . The Company represents and agrees that, unless it obtains the prior written consent of the Representatives, and each Underwriter severally represents and agrees that, unless it obtains the prior written

consent of the Company and the Representatives, it has not made and will not make any offer relating to the Securities that would constitute an issuer free writing prospectus or that would otherwise constitute a free writing prospectus required to be filed with the Commission; provided that the prior written consent of the parties hereto shall be deemed to have been given in respect of the free writing prospectuses included in Schedule III. Any such free writing prospectus consented to by the Company and the Representatives is hereinafter referred to as a “ Permitted Free Writing Prospectus .” The Company represents that it has treated or agrees that it will treat each Permitted Free Writing Prospectus as an issuer free writing prospectus, and has complied and will comply with the requirements of Rules 164 and 433 of the Rules and Regulations applicable to any Permitted Free Writing Prospectus. The Company represents that it has satisfied and agrees that it will satisfy the conditions in Rule 433 to avoid a requirement to file with the Commission any electronic road show.

(xiv) Emerging Growth Company . The Company will promptly notify the Representatives if the Company ceases to be an Emerging Growth Company at any time prior to the later of (A) completion of the distribution of Securities within the meaning of the Act and (B) completion of the 90-day restricted period referenced to in Section 4(a)(ix) hereof.

5. Conditions of Underwriters’ Obligations . The obligations of the several Underwriters hereunder are subject to the accuracy, as of the date hereof and at each of the First Closing Date and each Second Closing Date (as if made at such Closing Date), of and compliance with all representations, warranties and agreements of the Company contained herein, to the performance by the Company of their respective obligations hereunder and to the following additional conditions:

(a) Required Filings; Absence of Certain Commission Actions . All filings required by Rules 424, 430B and 433 of the Rules and Regulations shall have been timely made (without reliance on Rule 424(b)(8) or Rule 164(b)); no stop order suspending the effectiveness of the Registration Statement or any part thereof or any amendment thereof, nor suspending or preventing the use of the Time of Sale Disclosure Package, the Prospectus or any issuer free writing prospectus shall have been issued; no proceedings for the issuance of such an order shall have been initiated or threatened; and any request of the Commission for additional information (to be included in the Registration Statement, the Time of Sale Disclosure Package, the Prospectus, any issuer free writing prospectus or otherwise) shall have been complied with to your satisfaction, and the Commission shall not have notified the Company of any objection to the use of the form of the Registration Statement or any post-effective amendment thereto.

(b) Continued Compliance with Securities Laws . No Underwriter shall have advised the Company that (i) the Registration Statement or any amendment thereof or supplement thereto contains an untrue statement of a material fact which, in your opinion, is material or omits to state a material fact which, in your opinion, is required to be stated therein or necessary to make the statements therein not misleading, or (ii) the Time of Sale Disclosure Package or the Prospectus, or any amendment thereof or supplement thereto, or any issuer free writing prospectus contains an untrue statement of fact which, in your opinion, is material, or omits

to state a fact which, in your opinion, is material and is required to be stated therein, or necessary to make the statements therein, in light of the circumstances under which they are made, not misleading.

(c) Absence of Certain Events . Except as contemplated in the Time of Sale Disclosure Package and in the Prospectus, subsequent to the respective dates as of which information is given in the Time of Sale Disclosure Package and the Prospectus, neither the Company nor any of its subsidiaries shall have 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 its capital stock; and there shall not have been any change in the capital stock (other than a change in the number of outstanding shares of Common Stock due to the issuance of shares upon the exercise of outstanding options or warrants or conversion of convertible securities), or any material change in the short-term or long-term debt of the Company (other than as a result of the conversion of convertible securities), or any issuance of options, warrants, convertible securities or other rights to purchase the capital stock of the Company or any of its subsidiaries, or any Material Adverse Change or any development involving a prospective Material Adverse Change (whether or not arising in the ordinary course of business), that, in your judgment, makes it impractical or inadvisable to offer or deliver the Securities on the terms and in the manner contemplated in the Time of Sale Disclosure Package and in the Prospectus.

(d) No Downgrade . On or after the Time of Sale (i) no downgrading shall have occurred in the rating accorded the Company’s debt securities or preferred stock by any “nationally recognized statistical organization,” as that term is defined by the Commission for purposes of Section 3(a)(62) of the Exchange Act, and (ii) no such organization shall have publicly announced that it has under surveillance or review, with possible negative implications, its rating of any of the Company’s debt securities or preferred stock;

(e) Opinion and 10b-5 Statement of Counsel for the Company . On each Closing Date, there shall have been furnished to you, as Representatives of the several Underwriters, in form satisfactory to you: (x) the opinion and 10b-5 statement of Wilson Sonsini Goodrich & Rosati, P.C., counsel for the Company, dated such Closing Date and addressed to you (y) the opinion of Hogan Lovells US LLP, counsel for the company, dated such Closing Date and addressed to you, and (z) the opinion of Hogan Lovells International LLP, counsel for the Company, dated such Closing Date and addressed to you.

(g) Opinion 10b-5 Statement of Underwriters’ Counsel . On each Closing Date, there shall have been furnished to you, as Representatives of the several Underwriters, such opinion or opinions and 10b-5 statement from Latham & Watkins LLP, counsel for the several Underwriters, dated such Closing Date and addressed to you in form satisfactory to you, and such counsel shall have received such papers and information as they request to enable them to pass upon such matters.

(h) Comfort Letter . On the date hereof, on the effective date of any post-effective amendment to the Registration Statement filed after the date hereof and on each

Closing Date you, as Representatives of the several Underwriters, shall have received a letter of (i) Haskell & White LLP, dated such date and addressed to you, in form and substance satisfactory to you and (ii) KPMG LLP, dated such date and addressed to you, in form and substance satisfactory to you.

(i) Officers’ Certificate . On each Closing Date, there shall have been furnished to you, as Representatives of the Underwriters, a certificate, dated such Closing Date and addressed to you, signed by the chief executive officer and by the chief financial officer of the Company, to the effect that:

(i) The representations and warranties of the Company in this Agreement are true and correct as if made at and as of such Closing Date, and the Company has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied at or prior to such Closing Date; and

(ii) No stop order or other order suspending the effectiveness of the Registration Statement or any part thereof or any amendment thereof or the qualification of the Securities for offering or sale, nor suspending or preventing the use of the Time of Sale Disclosure Package, the Prospectus or any issuer free writing prospectus, has been issued, and no proceeding for that purpose has been instituted or, to the best of their knowledge, is contemplated by the Commission or any state or regulatory body.

(k) Lock-Up Agreement . The Underwriters shall have received all of the Lock-Up Agreements referenced in Section 4 and the Lock-Up Agreements shall remain in full force and effect.

(l) Other Documents . The Company shall have furnished to you and counsel for the Underwriters such additional documents, certificates and evidence as you or they may have reasonably requested.

(m) FINRA No Objections . FINRA shall have raised no objection to the fairness and reasonableness of the underwriting terms and arrangements.

(n) Exchange Listing . The Securities shall have been included for listing on the NYSE American and satisfactory evidence of such action shall have been provided to the Representatives

All such opinions, certificates, letters and other documents will be in compliance with the provisions hereof only if they are satisfactory in form and substance to you and counsel for the Underwriters. The Company will furnish you with such conformed copies of such opinions, certificates, letters and other documents as you shall reasonably request.

(a) The Company hereby agrees to indemnify and hold harmless each Underwriter, its affiliates, directors, officers, and employees and each person, if any, who controls any Underwriter within the meaning of Section 15 of the Act or Section 20 of the Exchange Act, from and against any loss, claim, damage or liability, joint or several, or any action in respect thereof (including, but not limited to, any loss, claim, damage, liability or action relating to purchases and sales of the Securities), to which that Underwriter, affiliate, director, officer, employee or controlling person may become subject, under the Act or otherwise, insofar as such loss, claim, damage, liability or action 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 in any amendment or supplement thereto, arising out of or caused by any omission or alleged 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 contained in the Time of Sale Disclosure Package, the Prospectus, any Permitted Free Writing Prospectus or any amendment or supplements thereto, or caused by the omission or alleged omission to state therein any material fact necessary to make the statements therein, in light of the circumstances under which they were made, not misleading, and shall reimburse each Underwriter and each such affiliate, director, officer, employee or controlling person promptly upon demand for any legal or other expenses reasonably incurred by that Underwriter, affiliate, director, officer, employee or controlling person in connection with investigating or defending or preparing to defend against any such loss, claim, damage, liability or action as such expenses are incurred; provided, however, that the Company shall not be liable in any such case to the extent that any such loss, claim, damage, liability or action arises out of, or is based upon, any untrue statement or alleged untrue statement or omission or alleged omission made in any Preliminary Prospectus, the Registration Statement, the Prospectus, any issuer free writing prospectus or in any such amendment or supplement thereto or in any Permitted Free Writing Prospectus, any marketing materials or any Blue Sky Application, in reliance upon and in conformity with written information concerning such Underwriter furnished to the Company through the Representatives by or on behalf of any Underwriter specifically for inclusion therein, which information consists solely of the information specified in Section 6(f). The foregoing indemnity agreement is in addition to any liability which the Company may otherwise have to any Underwriter or to any affiliate, director, officer, employee or controlling person of that Underwriter.

(c) Each Underwriter, severally and not jointly, shall indemnify and hold harmless the Company, its directors, officers and employees, and each person, if any, who controls the Company within the meaning of Section 15 of the Act or Section 20 of the Exchange Act, from and against any loss, claim, damage or liability, joint or several, or any action in respect thereof, to which the Company or any director, officer, employee or controlling person may become subject, under the Act or otherwise, insofar as such loss, claim, damage, liability or action 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 in any amendment or supplement thereto, arising out of or caused by any omission or alleged 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 contained in the Time of Sale Disclosure Package, any Permitted Free Writing Prospectus or any amendment or supplements thereto, or caused by the omission or alleged omission to state therein any material fact necessary to make the statements therein, in light of the circumstances under which they were made, not misleading, but in each case only to the extent that the untrue statement or alleged untrue statement or omission or alleged omission was made in reliance upon and in conformity with written information furnished to the Company through the Representatives by or on behalf of any Underwriter specifically for inclusion therein, which information is limited to the information set forth in Section 6(f). The foregoing indemnity agreement is in addition to any liability that any Underwriter may otherwise have to the Company or any director, officer, employee or controlling person.

(d) Promptly after receipt by an indemnified party under this Section 6 of notice of any claim or the commencement of any action, the indemnified party shall, if a claim in respect thereof is to be made against the indemnifying party under this Section 6, notify the indemnifying party in writing of the claim or the commencement of that action; provided , however , that the failure to notify the indemnifying party shall not relieve it from any liability which it may have under this Section 6 except to the extent it has been materially prejudiced (through the forfeiture of substantive rights and defenses) by such failure and, provided , further , that the failure to notify the indemnifying party shall not relieve it from any liability which it may have to an indemnified party otherwise than under this Section 6. If any such claim or action shall be brought against an indemnified party, and it shall notify the indemnifying party thereof, the indemnifying party shall be entitled to participate therein and, to the extent that it wishes, jointly with any other similarly notified indemnifying party, to assume the defense thereof with counsel reasonably satisfactory to the indemnified party. After notice from the indemnifying party to the indemnified party of its election to assume the defense of such claim or action, the indemnifying party shall not be liable to the indemnified party under this Section 6 for any legal or other expenses subsequently incurred by the indemnified party in connection with the defense thereof other than reasonable costs of investigation; provided, however , that the indemnified party shall have the right to employ one single counsel (and conditional local counsel) to represent jointly the indemnified party and those other indemnified parties and their respective directors, officers, employees and controlling persons who may be subject to liability arising out of any claim in respect of which indemnity may be sought under this Section 6 if (i) the indemnified party and the indemnifying party shall have so mutually agreed; (ii) the indemnifying party has failed within a reasonable time to retain counsel reasonably satisfactory to the indemnified party; (iii) the indemnified party and its directors, officers, employees and controlling persons shall have reasonably concluded that there may be legal defenses available to them that are different from or in addition to those available to the indemnifying party; or (iv) the named parties in any such proceeding (including any impleaded parties) include both the indemnified parties or their respective directors, officers, employees or controlling persons, on the one hand, and the indemnifying party, on the other hand, and representation of both sets of parties by the same counsel would be inappropriate due to actual or potential differing interests between them, and in any such event the fees and expenses of such separate counsel shall be paid by the indemnifying party. No indemnifying party shall (x) without the prior written consent of the indemnified parties (which consent shall not be unreasonably withheld), settle or compromise or consent to the entry of any judgment with respect to any pending or threatened claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to

such claim or action) unless such settlement, compromise or consent includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding and does not include a statement as to, or an admission of fault, culpability or a failure to act by or on behalf of any indemnified party, or (y) be liable for any settlement of any such action effected without its written consent (which consent shall not be unreasonably withheld), but if settled with the consent of the indemnifying party or if there be a final judgment for the plaintiff in any such action, the indemnifying party agrees to indemnify and hold harmless any indemnified party from and against any loss or liability by reason of 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 6(a) or (b) hereof, the indemnifying party agrees that it shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 30 days after receipt by such indemnifying party of the aforesaid request and (ii) such indemnifying party shall not have reimbursed the indemnified party in accordance with such request or disputed in good faith the indemnified party’s entitlement to such reimbursement prior to the date of such settlement.

(e) If the indemnification provided for in this Section 6 shall for any reason be unavailable to or insufficient to hold harmless an indemnified party under Section 6(a), 6(b) or 6(c) in respect of any loss, claim, damage or liability, or any action in respect thereof, referred to therein, then each indemnifying party shall, in lieu of indemnifying such indemnified party, contribute to the amount paid or payable by such indemnified party as a result of such loss, claim, damage or liability, or action in respect thereof, (i) in such proportion as shall be appropriate to reflect the relative benefits received by the Company, on the one hand, and the Underwriters, on the other, from the offering of the Securities, or (ii) if the allocation provided by clause (i) 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, with respect to the statements or omissions that resulted in such loss, claim, damage or liability, or action in respect thereof, 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, with respect to such offering shall be deemed to be in the same proportion as the total net proceeds from the offering of the Securities purchased under this Agreement (before deducting expenses) received by the Company, as set forth in the table on the cover page of the Prospectus, on the one hand, and the total underwriting discounts and commissions received by the Underwriters with respect to the shares of the Securities purchased under this Agreement, as set forth in the table on the cover page of the Prospectus, on the other hand. The relative fault shall be determined by reference to whether the 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 or the Underwriters, the intent of the parties and their relative knowledge, access to information and opportunity to correct or prevent such statement or omission. The Company and the Underwriters agree that it would not be just and equitable if contributions pursuant to this Section 6(e) were to be determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take into account the equitable considerations referred to herein. The amount paid or payable by an indemnified party as a result of the loss, claim, damage or liability, or action in respect thereof, referred to above in this Section 6(e) shall be deemed to include, for purposes of this Section 6(e),

any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any such action or claim. Notwithstanding the provisions of this Section 6(e), in no event shall an Underwriter be required to contribute any amount in excess of the amount by which the total underwriting discounts and commissions received by such Underwriter with respect to the offering of the Securities exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations to contribute as provided in this Section 6(e) are several in proportion to their respective underwriting obligations and not joint.

(f) The Underwriters severally confirm that the statements regarding delivery of shares by the Underwriters set forth on the cover page of, and the concession and reallowance figures, the paragraph relating to stabilization, short positions and penalty bids by the Underwriters, and the paragraph relating to other relationships appearing under the caption “Underwriting” in, the most recent Preliminary Prospectus and the Prospectus are true and correct. The Company acknowledges and agrees that such statements constitute the only information furnished in writing to the Company by or on behalf of the Underwriters specifically for inclusion in any Preliminary Prospectus, the Registration Statement, the Prospectus, any issuer free writing prospectus or in any amendment or supplement thereto or in any marketing materials.

7. Representations and Agreements to Survive Delivery . All representations, warranties, and agreements of the Company herein or in certificates delivered pursuant hereto, and the agreements of the several Underwriters and the Company contained in Section 6 hereof, shall remain operative and in full force and effect regardless of any investigation made by or on behalf of any Underwriter or any controlling person thereof, or the Company or any of their respective officers, directors, or controlling persons, and shall survive delivery of, and payment for, the Securities to and by the Underwriters hereunder and any termination of this Agreement.

(a) Obligation to Purchase Under Certain Circumstances . If any Underwriter or Underwriters shall fail to take up and pay for the amount of Firm Shares agreed by such Underwriter or Underwriters to be purchased hereunder, upon tender of such Firm Shares in accordance with the terms hereof, and the amount of Firm Shares not purchased does not aggregate more than 10% of the total amount of Firm Shares set forth in Schedule I hereto, the remaining Underwriters shall be obligated to take up and pay for (in proportion to their respective underwriting obligations hereunder as set forth in Schedule I hereto except as may otherwise be determined by you) the Firm Shares that the withdrawing or defaulting Underwriters agreed but failed to purchase.

(b) Termination Under Certain Circumstances . If any Underwriter or Underwriters shall fail to take up and pay for the amount of Firm Shares agreed by such Underwriter or Underwriters to be purchased hereunder, upon tender of such Firm Shares in accordance with the terms hereof, and the amount of Firm Shares not purchased aggregates to more than 10% of the total amount of Firm Shares set forth in Schedule I hereto, and arrangements

satisfactory to you for the purchase of such Firm Shares by other persons are not made within 36 hours thereafter, this Agreement shall terminate. In the event of any such termination the Company shall not be under any liability to any Underwriter (except to the extent provided in Section 4(a)(vii) and Section 6 hereof), nor shall any Underwriter (other than an Underwriter who shall have failed, otherwise than for some reason permitted under this Agreement, to purchase the amount of Firm Shares agreed by such Underwriter to be purchased hereunder) be under any liability to the Company (except to the extent provided in Section 6 hereof).

(c) Postponement of Closing . If Firm Shares to which a default relates are to be purchased by the non-defaulting Underwriters or by any other party or parties, the Representatives or the Company shall have the right to postpone the First Closing Date for not more than seven business days in order that the necessary changes in the Registration Statement, in the Time of Sale Disclosure Package, in the Prospectus or in any other documents, as well as any other arrangements, may be effected. As used herein, the term “Underwriter” includes any person substituted for an Underwriter under this Section 8.

(d) No Relief from Liability . No action taken pursuant to this Section 8 shall relieve any defaulting Underwriter from liability it may have to the Company or to any non-defaulting Underwriter, if any, in respect of damages resulting from such default.

(a) Right to Terminate . You, as Representatives of the several Underwriters, shall have the right to terminate this Agreement by giving notice as hereinafter specified at any time at or prior to the First Closing Date, and the option referred to in Section 3(b), if exercised, may be cancelled at any time prior to the applicable Second Closing Date, if (i) any condition of the Underwriters’ obligations hereunder is not fulfilled at the First Closing Date or Second Closing Date, as applicable, (ii) trading on the NYSE American, NASDAQ Stock Market or New York Stock Exchange shall have been wholly suspended, (iii) minimum or maximum prices for trading shall have been fixed, or maximum ranges for prices for securities shall have been required, on the NYSE American, NASDAQ Stock Market or New York Stock Exchange, by such Exchange or by order of the Commission or any other Governmental Authority, (iv) a banking moratorium shall have been declared by federal or state authorities, or (v) there shall have occurred any outbreak or escalation of hostilities involving or affecting the United States or there shall have occurred any change in financial markets or any calamity or crisis that, in your judgment, is material and adverse and makes it impractical or inadvisable to proceed with the completion of the sale of and payment for the Securities. Any such termination shall be without liability of any party to any other party except that the provisions of Section 4(a)(vii) and Section 6 hereof shall at all times be effective.

(b) Notice of Termination . If you elect to terminate this Agreement as provided in this Section, the Company shall be notified promptly by you by telephone, confirmed by letter.

(a) Default by the Company . If the Company shall fail at the First Closing Date to sell and deliver the number of Securities which each is respectively obligated to sell hereunder, then this Agreement shall terminate without any liability on the part of any Underwriter or, except as provided in Section 4(a)(vii) and Section 6 hereof, any non-defaulting party.

(b) No Relief from Liability . No action taken pursuant to this Section 10 shall relieve the Company from liability, if any, in respect of such default.

11. Notices . Except as otherwise provided herein, all communications hereunder shall be in writing and, if to the Underwriters, shall be mailed via overnight delivery service or hand delivered via courier, to the Representatives c/o Barclays Capital Inc., 745 Seventh Avenue, New York, New York 10019, Attention: Syndicate Registration (Fax: (646) 834-8133), with a copy, in the case of any notice pursuant to Section 6(d), to the Director of Litigation, Office of the General Counsel, Barclays Capital Inc., 745 Seventh Avenue, New York, New York 10019, with a copy (which shall not constitute notice) to Latham & Watkins LLP, 330 North Wabash Avenue, Suite 2800, Chicago, Illinois 60611, Attn: Christopher D. Lueking, and c/o William Blair & Company, L.L.C., 150 North Riverside Plaza, Chicago, Illinois 60606, Attn: General Counsel; and (ii) if to the Company, shall be mailed or delivered to it at 10790 Roselle Street, San Diego, California 92121, Attention: Chief Financial Officer, with a copy to Wilson Sonsini Goodrich & Rosati, P.C., 12235 El Camino Real, Suite 200, San Diego, California 92130, Attn: Daniel R. Koeppen. Any party to this Agreement may change such address for notices by sending to the parties to this Agreement written notice of a new address for such purpose.

12. Persons Entitled to Benefit of Agreement . This Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective successors and assigns and the controlling persons, officers and directors referred to in Section 6. Nothing in this Agreement is intended or shall be construed to give to any other person, firm or corporation any legal or equitable remedy or claim under or in respect of this Agreement or any provision herein contained. The term “successors and assigns” as herein used shall not include any purchaser, as such purchaser, of any of the Securities from any of the several Underwriters.

13. Absence of Fiduciary Relationship . The Company and agrees that: (a) the Underwriters have been retained solely to act as an underwriter in connection with the sale of the Securities and that no fiduciary, advisory or agency relationship between the Company and the Underwriters has been created in respect of any of the transactions contemplated by this Agreement, irrespective of whether the Underwriters have advised or are advising the Company on other matters; (b) the price and other terms of the Securities set forth in this Agreement were established by the Company following discussions and arms-length negotiations with the Underwriters and the Company is capable of evaluating and understanding and the Company understands and accepts the terms, risks and conditions of the transactions contemplated by this Agreement; (c) it has been advised that the Underwriters and their affiliates are engaged in a broad range of transactions which may involve interests that differ from those of the Company and that the Underwriters have no obligation to disclose such interest and transactions to the Company by virtue of any fiduciary, advisory or agency relationship; (d) it has been advised that the Underwriters are acting, in respect of the transactions contemplated by this Agreement,

solely for the benefit of the Underwriters, and not on behalf of the Company; (e) the Company waives to the fullest extent permitted by law, any claim it may have against the Underwriters for breach of fiduciary duty or alleged breach of fiduciary duty in respect of any of the transactions contemplated by this Agreement and agrees that the Underwriters shall have no liability (whether direct or indirect) to the Company in respect of such a fiduciary duty claim on behalf of or in right of the Company, including stockholders, employees or creditors of the Company.

14. Governing Law; Waiver of Jury Trial . This Agreement shall be governed by and construed in accordance with the laws of the State of New York. The Company (on its behalf and, to the extent permitted by applicable law, on behalf of its stockholders and affiliates) and each of the Underwriters hereby irrevocably waive, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated hereby.

15. Counterparts . This Agreement may be executed in one or more original, PDF or facsimile counterparts and, if executed in more than one counterpart, the executed counterparts shall each be deemed to be an original and all such counterparts shall together constitute one and the same instrument.

16. 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 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.

Please sign and return to the Company the enclosed duplicates of this Agreement whereupon this Agreement will become a binding agreement between the Company and the several Underwriters in accordance with its terms.


Very truly yours,

P FENEX I NC .

By		/s/ Susan A. Knudson
		Susan A. Knudson Chief Financial Officer

The undersigned understands that you and certain other firms (the “ Underwriters ”) propose to enter into an Underwriting Agreement (the “ Underwriting Agreement ”) providing for the purchase by the Underwriters of shares (the “ Stock ”) of Common Stock, par value $0.001 per share (the “ Common Stock ”), of Pfenex Inc., a Delaware corporation (the “ Company ”), and that the Underwriters propose to reoffer the Stock to the public (the “ Offering ”).

In consideration of the execution of the Underwriting Agreement by the Underwriters, and for other good and valuable consideration, the undersigned hereby irrevocably agrees that, without the prior written consent of Barclays Capital Inc. and William Blair & Company, L.L.C., on behalf of the Underwriters, the undersigned will not, directly or indirectly, (1) offer for sale, sell, pledge, or otherwise dispose of (or enter into any transaction or device that is designed to, or could be expected to, result in the disposition by any person at any time in the future of) any shares of Common Stock (including, without limitation, shares of Common Stock that may be deemed to be beneficially owned by the undersigned in accordance with the rules and regulations of the Securities and Exchange Commission (the “ Commission ”) and shares of Common Stock that may be issued upon exercise of any options or warrants) or securities convertible into or exercisable or exchangeable for Common Stock, (2) enter into any swap or other derivatives transaction that transfers to another, in whole or in part, any of the economic benefits or risks of ownership of shares of Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or other securities, in cash or otherwise, (3) make any demand for or exercise any right or cause to be filed a registration statement, including any amendments thereto, with respect to the registration of any shares of Common Stock or securities convertible into or exercisable or exchangeable for Common Stock or any other securities of the Company, or (4)

publicly disclose the intention to do any of the foregoing for a period commencing on the date hereof and ending on the 90th day after the date of the Prospectus relating to the Offering (such 90-day period, the “ Lock-Up Period ”).

The foregoing paragraph shall not apply to (a) transactions relating to shares of Common Stock or other securities acquired in the open market after the completion of the offering, (b) transfers of shares of any class of the Company’s capital stock (i) as part of a distribution to limited partners, members or stockholders of the undersigned, (ii) to the undersigned’s affiliates or to any investment fund or other entity controlled or managed by the undersigned, (iii) by will or intestacy, bona fide gifts, sales or other dispositions in each case (except with respect to transfers by will or intestacy) that are made exclusively between and among the undersigned or members of the undersigned’s family or to a trust formed for the benefit of undersigned or members of the undersigned’s family or (iv) to a nominee or custodian of a person or entity to whom a disposition or transfer would be permissible under clauses (i) through (iii) above; provided, that (i) it shall be a condition to any transfer pursuant to this clause (b) that the transferee/donee agrees to be bound by the terms of this Lock-Up Letter Agreement (including, without limitation, the restrictions set forth in the preceding sentence) to the same extent as if the transferee/donee were a party hereto and (ii) that no filing by any party under Section 16(a) of the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), shall be required or shall be made voluntarily in connection with such transfer, (c) the exercise of warrants or the exercise of stock options (including, in each case, on a “net” or “cashless” basis or to cover tax withholding obligations of the undersigned) granted pursuant to the Company’s stock option/incentive plans or otherwise outstanding on the date hereof; provided , that (i) the restrictions shall apply to shares of Common Stock issued upon such exercise or conversion, (ii) if any public reports or filings are required under Section 16 of the Exchange Act, any such public report or filing under Section 16 of the Exchange Act shall clearly indicate in the footnotes thereto that the filing relates to the exercise of a stock option or warrant, that no shares were sold by the reporting person and that the shares received upon exercise of the stock option or warrant are subject to a lock-up agreement with the Underwriters of the Offering and (iii) in the event of an exercise on a “net” basis, the Company becomes the owner of the shares of Common Stock surrendered in the net exercise, (d) the establishment of any contract, instruction or plan that satisfies all of the requirements of Rule 10b5-1 (a “ Rule 10b5-1 Plan ”) under the Exchange Act; provided , however , that no sales of Common Stock or securities convertible into, or exchangeable or exercisable for, Common Stock, shall be made pursuant to any such Rule 10b5-1 Plan prior to the expiration of the Lock-Up Period (as the same may be extended pursuant to the provisions hereof); provided further , that the Company is not required to report the establishment of such Rule 10b5-1 Plan in any public report or filing with the Commission under the Exchange Act during the Lock-Up Period and does not otherwise voluntarily effect any such public filing or report regarding such Rule 10b5-1 Plan, (e) sales of Common Stock pursuant to a Rule 10b5-1 Plan in existence prior to the date hereof; provided , that to the extent a public announcement or filing under the Exchange Act, if any, is required or voluntarily made by or on behalf of the undersigned or the

Company regarding any such sales or transfers, such announcement or filing shall clearly indicate in the footnotes thereto a statement to the effect that the sale or transfer was made pursuant to a trading plan pursuant to Rule 10b5-1 entered into prior to the date hereof, (f) the transfer of shares of the undersigned’s Common Stock or securities convertible into, or exchangeable or exercisable for, Common Stock pursuant to a bona fide third party tender offer, merger, consolidation or other similar transaction made to all holders of the Common Stock involving a change of control of the Company; provided that in the event that the tender offer, merger, consolidation or other such transaction is not completed, the undersigned’s securities shall remain subject to the restrictions contained in this Agreement and (g) any demands or requests for, or the exercise of any right with respect to, the registration by the Company under the Securities Act of 1933, as amended (the “ Act ”), of the undersigned’s shares of Common Stock, provided that no transfer of the undersigned’s shares of Common Stock registered pursuant to the exercise of any such right and no registration statement shall be filed under the Act with respect to any of the undersigned’s shares of Common Stock during the Lock-Up Period.

In furtherance of the foregoing, the Company and its transfer agent are hereby authorized to decline to make any transfer of securities if such transfer would constitute a violation or breach of this Lock-Up Letter Agreement.

It is understood that, if the Company notifies the Underwriters that it does not intend to proceed with the Offering, if the Underwriting Agreement does not become effective, or if the Underwriting Agreement (other than the provisions thereof which survive termination) shall terminate or be terminated prior to payment for and delivery of the Stock, the undersigned will be released from its obligations under this Lock-Up Letter Agreement.

The undersigned understands that the Company and the Underwriters will proceed with the Offering in reliance on this Lock-Up Letter Agreement.

Whether or not the Offering actually occurs depends on a number of factors, including market conditions. Any Offering will only be made pursuant to an Underwriting Agreement, the terms of which are subject to negotiation between the Company and the Underwriters.

This Lock-Up Letter Agreement shall automatically terminate upon the earliest to occur, if any, of (1) the termination (other than the provisions thereof which survive termination) of the Underwriting Agreement before the sale of any Stock to the Underwriters, (2) the Company advises the Representatives in writing that it has determined not to proceed with the Offering or (3) June 30, 2018, in the event that the Underwriting Agreement has not been executed by that date (provided that the Company may by written notice to the undersigned extend such date for a period of up to three additional months).

This Lock-Up Letter Agreement shall be governed by, and construed in accordance with, the laws of the State of New York.

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Lock-Up Letter Agreement and that, upon request, the undersigned will execute any additional documents necessary in connection with the enforcement hereof. Any obligations of the undersigned shall be binding upon the heirs, personal representatives, successors and assigns of the undersigned.


Very truly yours,


		Printed Name of Holder

By:
		Signature

Printed Name of Person Signing (and indicate capacity of person signing if signing as custodian, trustee, or on behalf of an entity)


Delaware	001-36540	27-1356759
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification No.)


Exhibit No.		Description

1.1		Underwriting Agreement, dated as of May 23, 2018, by and among Pfenex Inc. and Barclays Capital Inc. and William Blair & Company, L.L.C. as representatives of the underwriters.

5.1		Opinion of Wilson Sonsini Goodrich & Rosati, Professional Corporation.

23.1		Consent of Wilson Sonsini Goodrich & Rosati, Professional Corporation (included in Exhibit 5.1).


		PFENEX INC.

Date: May 23, 2018	By:	/s/ Susan A. Knudson
		Susan A. Knudson Chief Financial Officer (Principal Financial Officer)


By:		/s/ Victoria Hale
		Authorized Representative

By W ILLIAM B LAIR & C OMPANY , L.L.C.

By:		/s/ Steve Maletzky
		Authorized Representative


Underwriters		Number of Firm Shares ⁽¹⁾
Barclays Capital Inc.		3,828,400
William Blair & Company, L.L.C.		2,971,600
Total		6,800,000


Dated: