Advisory Agreement, dated December 12, 2019, by and between the Registrant and Roger Pomerantz

Services. The Company hereby engages Advisor to provide to the Company, and Advisor agrees to provide to the Company under the terms and conditions of this Agreement, board advisory services as reasonably requested by the Company from time to time (hereinafter the "Services").

Compensation. As consideration for Advisor’s Services, the Company will pay to Advisor a quarterly retainer in the amount of $8,750 per quarter (and pro-rated for partial quarters) due at the end of each calendar quarter. The retainer will give the Company access to the Advisor’s Services for up to 15 hours per quarter. In addition, the Parties agree that notwithstanding their contrary terms, with respect to those outstanding options to purchase shares of the Company’s common stock held by Advisor on the Effective Date, which options are set forth on Exhibit A to this Agreement, Advisor’s service under this Agreement shall constitute continued service to the Company such that (i) with respect to the option to purchase 15,000 shares of the Company’s common stock granted to Advisor on June 13, 2019, such option will continue to vest during the Term (as defined below), and (ii) with respect to all such outstanding options, such options will remain exercisable during the Term and the post-termination exercise period of such options will not commence until the expiration of the Term. For the avoidance of doubt, effective as of the Effective Date, Advisor will no longer be eligible to receive compensation for service on the Board under the Company’s Non-Employee Director Compensation program.

Expenses. The Company will reimburse Advisor for reasonable and necessary out-of-pocket expenses incurred by Advisor in the performance of the Services, provided such out-of-pocket expenses are approved in advance by an officer of the Company and further are supported by reasonable documentation. Such expenses will include reasonable travel expenses of Advisor to the Company's offices.

Independent Contractor. Advisor is not, nor will Advisor be deemed to be at any time during the term of this Agreement, an employee of the Company, and therefore Advisor will not be entitled to any benefits provided by the Company to its employees (including such items as health and disability benefits, but except as otherwise provided in the Separation Agreement with respect to continued medical, dental or vision coverage pursuant to COBRA), even if it is later determined that Advisor is a common law employee of Company or any of its affiliates for any purpose. Advisor's status and relationship with the Company will be that of an independent contractor and consultant. Advisor will not state or imply, directly or indirectly, that Advisor is empowered to bind the Company without the Company's prior written consent. Nothing herein will create, expressly or by implication, a partnership, joint venture or other association between the parties. Advisor will be solely responsible for payment of all charges and taxes arising from his or her relationship to the Company.

Term of Agreement. The term of this Agreement and Advisor's Services hereunder will commence as of the Effective Date of this Agreement and, unless terminated earlier as a result of the death, physical incapacity or mental incompetence of Advisor, which will result in automatic termination, or unless terminated pursuant to Section 6, it will continue in effect until the date on which the Company publicly announces the top-line results of the SER-287 Phase 2b clinical study (the "Initial Term"). The term of this Agreement may be extended beyond the Initial Term for additional periods upon mutual written agreement of the parties. Upon expiration or termination of this Agreement all obligations of the parties hereunder shall cease except that the provisions of Sections 7 through 13 will survive the termination or expiration of this Agreement for any reason. The period from the Effective Date through the expiration or termination of this Agreement, regardless of the time or reason for such termination, shall be referred to herein as the “Term”.

Termination. Either Party may, without prejudice to any right or remedy it may have due to any failure of the other Party to perform its obligations under this Agreement, terminate the Term immediately by written notice to the other Party in the event of a material breach of this Agreement by such other Party. The Company may terminate the Term at any time by ten (10) days’ written notice to Advisor.  If prior to the expiration of the Initial Term the Company terminates the Term other than due to Advisor’s material breach of this Agreement, Advisor shall be entitled to the payments and benefits (including, for the avoidance of doubt, continued vesting and exercisability of Advisor’s options to purchase shares of the Company’s common stock) set forth in Section 2 of this Agreement as if Advisor had continued providing the Services until the expiration of the Initial Term. In the event of termination under this Section 6 at any time, the Advisor shall be entitled to payment for Services performed and expenses paid or incurred prior to the effective date of termination and shall have no further rights under this Agreement.  Such payments shall constitute full settlement of any and all claims of the Advisor of every description against the Company under this Agreement.

Representations and Warranties of Advisor. Advisor represents and warrants to the Company that (i) with respect to any information, know-how, knowledge or data disclosed by Advisor to the Company or any other third party in the performance of this Agreement, Advisor has the full and unrestricted right to disclose the same; and (ii) Advisor is free to undertake the Services required by this Agreement, and there is, and will be, no conflict of interest between Advisor's performance of this Agreement and any obligation Advisor may have to other parties.  

Covenants of Advisor. Notwithstanding anything herein to the contrary, Advisor agrees to continue to abide by the terms of the Employee Non-Competition, Non-Solicitation, Confidentiality and Assignment Agreement previously entered into between Advisor and the Company (the “Proprietary Information Agreement”), which are hereby incorporated by reference into this Agreement and which shall apply in addition to the other covenants set forth in this Agreement.

Confidentiality. Advisor agrees to hold all Confidential Information (as hereinafter defined) of the Company (or other parties whose Confidential Information the Company has in its possession under obligations of confidentiality) in trust and strict confidence and, except as may be authorized by the Company in writing, will not use for any purpose other than the performance of the Services under this Agreement, nor disclose such Confidential Information to any person, association, company, entity or other organization (whether for profit or not for profit).

Ownership of Work Product. Advisor will communicate in writing and disclose to the Company promptly and fully all concepts, inventions, formulae, molecules, organisms, trade secrets, know-how, technical or business innovations, writings or other works of authorship and patents or patent rights created, reduced to practice, or conceived by Advisor (whether or not patentable or copyrightable and whether made solely by Advisor or jointly with others), which result from the Services that Advisor performs for the Company or which result from use of Confidential Information (along with all patent, copyright and other proprietary rights arising therefrom, collectively the "Works").

Company Data. Any data or other materials furnished by the Company for use by Advisor in connection with the Services will remain the sole property of the Company and will be held in trust and confidence by Advisor in accordance with Section 9 as Confidential Information. The Company may obtain the return of the Company data or other materials furnished to Advisor upon written notice to Advisor requesting such return, and in any event Advisor will promptly return such data or materials upon termination of this Agreement.

Advertising. Advisor will not in any way or in any form publicize or advertise in any manner the fact that Advisor is performing the services called for by this Agreement without the prior written consent of the Company.

Restriction on Solicitation. During the Term and for one year thereafter, Advisor will not recruit or otherwise solicit, entice and induce any employee of the Company to terminate their employment with, or otherwise cease their relationships with the Company.

Trade Secrets. In accordance with 18 U.S.C. §1833, notwithstanding anything to the contrary in this Agreement, the Proprietary Information Agreement or any other agreement between Advisor and the Company or any of its subsidiaries in effect as of the Effective Date (together, the “Subject Documents”): (a) Advisor will not be in breach of the Subject Document, and shall not be held criminally or civilly liable under any federal or state trade secret law (i) for the disclosure of a trade secret that is made in confidence to a federal, state, or local government official or to an attorney solely for the purpose of reporting or investigating a suspected violation of law, or (ii) for the disclosure of a trade secret that is made in a complaint or other document filed in a lawsuit or other proceeding, if such filing is made under seal; and (b) if Advisor files a lawsuit for retaliation by the Company for reporting a suspected violation of law, Advisor may disclose the trade secret to Advisor’s attorney, and may use the trade secret information in the court proceeding, if Advisor files any document containing the trade secret under seal, and does not disclose the trade secret, except pursuant to court order.

Assignment. The rights and liabilities of the parties hereto shall bind and inure to the benefit of their respective successors, heirs, executors and administrators, as the case may be; provided that, as the Company has specifically contracted for Advisor's Services, Advisor may not assign or delegate Advisor's obligations under this Agreement either in whole or in part without the prior written consent of the Company. The Company may assign its rights and obligations hereunder to any person or entity that succeeds to all or substantially all of the Company's business. Any assignment not in accordance with this Section 15 shall be void.

Section 409A. The intent of the Parties is that the payments and benefits under this Agreement comply with or be exempt from Section 409A of the Internal Revenue Code of 1986, as amended (“Section 409A”), and, to the maximum extent permitted, this Agreement will be interpreted accordingly. Notwithstanding anything in this Agreement to the contrary, any compensation or benefits payable under this Agreement upon termination of the Term and that constitutes “non-qualified deferred compensation” under Section 409A shall be payable only upon Advisor’s “separation from service” with the Company within the meaning of Section 409A (a “Separation from Service”).  If Advisor is deemed by the Company at the time of Advisor’s Separation from Service to be a “specified employee” for purposes of Section 409A, to the extent delayed commencement of any portion of the benefits to which Advisor is entitled under this Agreement is required in order to avoid a prohibited distribution under Section 409A, such portion of Advisor’s benefits shall not be provided to Advisor prior to the earlier of (i) the expiration of the six-month period measured from the date of Advisor’s Separation from Service with the Company or (ii) the date of Advisor’s death.  Upon the first business day following the expiration of the applicable Section 409A period, all payments deferred pursuant to the preceding sentence will be paid in a lump sum to Advisor (or Advisor’s estate or beneficiaries), and any remaining payments due to Advisor under this Agreement will be paid as otherwise provided herein.  Advisor’s right to receive any installment payments under this Agreement will be treated as a right to receive a series of separate payments for purposes of Section 409A.

Miscellaneous. This Agreement (together with all exhibits hereto), the Separation Agreement and the Proprietary Information Agreement, contain the entire understanding of the parties with respect to the matters contained herein, and supersedes all proposals and agreements, written or oral, and all other communications between the parties relating to the subject matter of this Agreement. This Agreement will be governed by and construed in accordance with the laws of the Commonwealth of Massachusetts without regard to its conflict of laws rules that would result in the application of the laws of another jurisdiction. Advisor and the Company each hereby submits to the exclusive personal jurisdiction of the federal and state courts located in Massachusetts in connection with any disputes as to the meaning, effect, performance or validity of this Agreement or arising out of, related to, or in any way connected with, this Agreement or Advisor’s relationship with the Company. This Agreement may not be modified or amended except in writing signed or executed by Advisor and the Company. In the event any provision of this Agreement is held to be unenforceable or invalid because it is overbroad or too far reaching, such provision will be deemed to be revised so that it applies to the maximum extent permitted by law.

ADVISOR

SERES THERAPEUTICS, INC.

/s/ Roger J. Pomerantz

By:

/s/ Eric D. Shaff

Name:

Roger J. Pomerantz, M.D.

Name:

Eric D. Shaff

Address:

Title:

President and CEO

Date of Grant

Total Shares

Subject to

Option

Exercise Price

per Share

Vested Shares

as of Effective

Date

Vested and

Unexercised as of

Effective Date

Unvested

Shares as of

Effective Date

Nov. 6, 2013

220,000

$0.48

220,000

82,500

-

Aug. 7, 2014

1,675,751

$0.71

1,675,751

797,536

-

Feb. 1, 2016

176,500

$26.20

121,343*

121,343

-

Jan. 26, 2017

261,000

$9.89

114,187*

114,187

-

Jun. 13, 2019

15,000

$2.83

-

-

15,000