8-K - MCRB - Equibles

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): February 27, 2026

SERES THERAPEUTICS, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware	001-37465	27-4326290
(State or other jurisdiction<br> <br>of incorporation)	(Commission<br> <br>File Number)	(IRS Employer<br> <br>Identification No.)
101 Cambridgepark Drive
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Cambridge, MA	02140
(Address of principal executive offices)	(Zip Code)

Registrant’s telephone number, including area code: (617) 945-9626

Not Applicable

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
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☐	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
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☐	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
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Securities registered pursuant to Section 12(b) of the Act:

Title of each class	Trading<br>Symbol(s)	Name of each exchange<br> <br>on which registered
Common stock, par value $0.001 per share	MCRB	The Nasdaq Stock Market LLC<br> <br>(Nasdaq Global Select Market)

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 5.02.	Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On February 27, 2026, the Board of Directors (the “Board”) of Seres Therapeutics, Inc. (the “Company”) appointed Richard N. Kender, a current member of the Board, to serve as Executive Chair of the Board and as Interim Chief Executive Officer of the Company, Matthew Henn, Ph.D., the Company’s Chief Scientific Officer, to the additional role of President, and Kelly Brady, M.S., the Company’s Senior Vice President, Clinical Development, to the role of Executive Vice President, Chief Operating Officer, each effective March 2, 2026 (the “Effective Date”).

As a result of the appointment of Mr. Kender as Interim Chief Executive Officer, Thomas J. DesRosier and Marella Thorell ceased serving as Co-Presidents and Co-Chief Executive Officers of the Company as of the Effective Date. Mr. DesRosier will continue to serve as the Company’s Executive Vice President, Chief Legal Officer, and Ms. Thorell will continue to serve as the Company’s Executive Vice President, Chief Financial Officer.

A description of each of Mr. Kender’s and Dr. Henn’s business experience can be found in the Company’s definitive proxy statement on Schedule 14A, filed with the Securities and Exchange Commission on March 13, 2025, and is incorporated by reference herein. Prior to joining the Company in 2018, Ms. Brady was Senior Director and Global Clinical Program Lead at Akebia Therapeutics, Inc., where she oversaw pivotal programs in anemia due to chronic kidney disease. She also held roles of increasing responsibility in operations and program management at Acetylon Pharmaceuticals, Inc., with the company’s eventual acquisition by Celgene Corporation. Earlier in her career, she served as the Global Phase 3 Clinical Operations Leader at Millennium Pharmaceuticals, Inc. (later Takeda Oncology), executing pivotal global oncology trials for ADCETRIS®, and as a member of the operations team at Osiris Therapeutics, Inc., managing global graft-versus-host disease studies for the world’s first approved stem-cell therapy Prochymal. Ms. Brady holds a B.S. in Neuroscience from Lafayette College and an M.S. in Biotechnology from Johns Hopkins University.

There are no family relationships between each of Mr. Kender, Dr. Henn and Ms. Brady and any director or executive officer of the Company that would be required to be disclosed pursuant to Item 401(d) of Regulation S-K, and neither of Mr. Kender, Dr. Henn and Ms. Brady has a material interest in any transaction that is required to be disclosed under Item 404(a) of Regulation S-K.

Compensation Arrangements

On the Effective Date, the Company and Mr. Kender entered into an employment letter agreement under which Mr. Kender will receive an annual base salary of $520,000 and be eligible to earn a discretionary annual bonus with a target amount equal to 55% of his annual base salary. The letter also provides for Mr. Kender to receive a one-time signing bonus in the amount of $250,000, which amount is subject to repayment if his employment is terminated by the Company for “cause” or by Mr. Kender without “good reason” (as such terms are defined in the agreement) before December 31, 2026. While employed, Mr. Kender will not be eligible for compensation as a non-employee director under the Company’s Non-Employee Director Compensation Program. However, his employment will be deemed to satisfy any continued service requirements that apply under his existing Company equity awards, with the effect that the awards will continue to vest and, as applicable, remain exercisable during his employment and thereafter during any period that he otherwise continues to satisfy the applicable service conditions in accordance with the terms of the awards. In addition, the Board approved the grant to Mr. Kender of options to purchase 200,000 shares of the Company’s common stock, effective on the second business day after the filing of this Current Report. The options have an exercise price equal to the fair market value of the Company’s common stock on the effective date of grant, as determined under the Company’s 2025 Incentive Award Plan (the “Plan”), and vest in 36 equal monthly installments after the effective date, subject to Mr. Kender’s continued service to the Company and potential accelerated vesting if the Company terminates Mr. Kender’s employment without “cause” or he resigns for “good reason” within 60 days prior to or 12 months following a change in control. Twenty-five percent of the options is subject to approval by the Company’s stockholders of an amendment to the Plan to increase the number of

shares available thereunder (which amendment was approved by the Board on February 27, 2026) and will be forfeited if the Plan amendment is not approved at or before the Company’s 2026 annual meeting of stockholders. In addition, under the terms of the letter, all unvested options held by Mr. Kender will vest in the event of his death.

Also on the Effective Date, the Company and Dr. Henn entered into a letter agreement that amends his existing employment agreement with the Company. Under the amendment, Dr. Henn’s annual base salary was increased to $505,000 and his target annual bonus was increased to 45% of his annual base salary. Dr. Henn was also awarded a one-time retention bonus in the amount of $230,000. The retention bonus is subject to repayment if Dr. Henn’s employment is terminated by the Company for “cause” or by Dr. Henn without “good reason” (as such terms are defined in his employment agreement with the Company) before December 31, 2026. In addition, the Board approved the grant to Dr. Henn of options to purchase 100,000 shares of the Company’s common stock, effective on the second business day after the filing of this Current Report. The options have an exercise price equal to the fair market value of the Company’s common stock on the effective date of grant, as determined under the Plan, and vest as to 25% of the underlying shares on the first anniversary of the effective date and as to an additional 6.25% of such shares upon Dr. Henn’s completion of each three months of continuous service to the Company thereafter, subject to potential accelerated vesting if the Company terminates Dr. Henn’s employment without “cause” or he resigns for “good reason” within 60 days prior to or 12 months following the date of a change in control. Twenty-five percent of the options is subject to approval by the Company’s stockholders of the Plan amendment described above and will be forfeited if the Plan amendment is not approved at or before the Company’s 2026 annual meeting of stockholders.

On the Effective Date, the Company and Ms. Brady entered into a letter agreement that amends her existing employment agreement with the Company. Under the amendment, Ms. Brady’s annual base salary was increased to $475,000, her target annual bonus amount was increased to 45% of her annual base salary, the cash severance benefits payable under her employment agreement in the event of her qualifying termination of employment was increased to 1.0 times the sum of her annual base salary and target annual bonus for a qualifying termination within the 60 days before or 12 months after a change in control and to 12 months of base salary for other qualifying terminations, and the period during which Ms. Brady is entitled to receive subsidized COBRA payments upon a qualifying termination was correspondingly increased to 12 months. Ms. Brady was also awarded a one-time retention bonus in the amount of $230,000. The retention bonus is subject to repayment if Ms. Brady’s employment is terminated by the Company for “cause” or by Ms. Brady without “good reason” (as such terms are defined in her amended employment agreement) before December 31, 2026. In addition, the Board approved the grant to Ms. Brady of options to purchase 75,000 shares of the Company’s common stock, effective on the second business day after the filing of this Current Report. The options have an exercise price equal to the fair market value of the Company’s common stock, as determined under the Plan, and vest as to 25% of the underlying shares on the first anniversary of the effective date and as to an additional 6.25% of such shares upon Ms. Brady’s completion of each three months of continuous service to the Company thereafter, subject to potential accelerated vesting if the Company terminates Ms. Brady’s employment without “cause” or she resigns for “good reason” within 60 days prior to or 12 months following the date of a change in control. Twenty-five percent of the options is subject to approval by the Company’s stockholders of the Plan amendment described above and will be forfeited if the Plan amendment is not approved at or before the Company’s 2026 annual meeting of stockholders.

The foregoing descriptions of the Company’s employment letter agreement with Mr. Kender and the letter agreements with Dr. Henn and Ms. Brady do not purport to be complete and are qualified in their entirety by reference to the complete text of the respective agreements.

Forward-Looking Statements

This Current Report contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this Current Report that do not relate to matters of historical fact should be considered forward-looking statements, including without limitation statements regarding executive transitions, compensation arrangements, [including the Pro Rata Bonus and Appointment Bonuses,] and the timing of any of the foregoing. These forward-looking statements are based on management’s current expectations. These statements are neither promises nor guarantees, but involve known and unknown risks, uncertainties and other important factors that may cause the Company’s actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking

statements, including, but not limited to, the important factors discussed under the caption “Risk Factors” in the Company’s Quarterly Report on Form 10-Q filed with the SEC on November 5, 2025, and the Company’s other reports filed with the Securities and Exchange Commission could cause actual results to differ materially from those indicated by the forward-looking statements made in this Current Report. Any such forward-looking statements represent management’s estimates as of the date of this Current Report. While we may elect to update such forward-looking statements at some point in the future, we disclaim any obligation to do so, even if subsequent events cause the Company’s views to change. These forward-looking statements should not be relied upon as representing the Company’s views as of any date subsequent to the date of this Current Report.

Item 9.01	Financial Statements and Exhibits.

(d) Exhibits.

Exhibit No.	Description
10.1	Letter Agreement dated March 2, 2026, by and between the Registrant and Kelly M. Brady.
10.2	Letter Agreement dated March 2, 2026, by and between the Registrant and Matthew Henn, Ph.D.
10.3	Employment Letter Agreement dated March 2, 2026, by and between the Registrant and Richard N. Kender.
104	Cover Page Interactive Data File (embedded within the inline XBRL document).

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	SERES THERAPEUTICS, INC.
Date: March 2, 2026	By:	/s/ Thomas J. DesRosier
	Name:	Thomas J. DesRosier
	Title:	Executive Vice President, Chief Legal Officer

EX-10.1

Exhibit 10.1

Seres Therapeutics, Inc.

101 Cambridge Park Drive

Cambridge, Massachusetts 02140

March 2, 2026

Kelly M. Brady

By Email Delivery

Dear Kelly,

Seres Therapeutics, Inc. (the “Company”) is pleased to confirm its offer to continue to employ you as a regular, full-time employee on the following terms, effective March 2, 2026 (the “Effective Date”):

**Employment Agreement.**The terms of the Amended and Restated Employment Agreement between you and the Company in effect on the date hereof and attached hereto as Exhibit A (the “Employment Agreement”) will remain in effect and continue to govern the terms of your employment except as provided in this letter. Capitalized terms used but not defined in this letter have the meaning provided in the Employment Agreement.
Position; Effective Date. Commencing on the Effective Date, you will serve as Executive Vice President and Chief Operating Officer of the Company. In this capacity you will initially report to Richard N. Kender, the Company’s Executive Chair, who as of the Effective Date will be the Supervisor under (and within the meaning of) the Employment Agreement. For the avoidance of doubt, neither the change in your reporting to the Executive Chair as of the Effective Date nor a subsequent change in your reporting from the Executive Chair to the Company’s Chief Executive Officer will by itself be considered Good Reason under the Employment Agreement.
Annual Base Salary; Work Location. Your Annual Base Salary for this position will be at the rate of $475,000 per year. Your Annual Base Salary will be paid in installments in accordance with the Company’s payroll practices and procedures as in effect from time to time and will be prorated for any partial period of employment. Your normal place of work will be the Company’s offices in Cambridge, Massachusetts.
Annual Target Bonus. As of the Effective Date, your Target Bonus will be 45% of your Annual Base Salary, prorated for any partial year of employment. The actual amount of any Annual Bonus will be determined by the Company’s Board of Directors or an authorized committee thereof (the “Board”) in its discretion, taking into consideration both the Company’s performance and your individual performance. The payment of any Annual Bonus will be subject to your continued employment with the Company through the date of payment, except as otherwise provided in Section 4(b) of the Employment Agreement.
Equity Award. Subject to approval by the Board, the Company will grant you options (the “Options”) under the Company’s 2025 Incentive Award Plan (the “Plan”) to purchase 75,000shares of the Company’s common stock (subject to adjustment for corporate events as set forth in the Plan) at an exercise price per share equal to the per share fair market value of the Company’s common stock on the date of grant, as determined in accordance with the Plan, provided that 25% of the Options (the “ContingentOption”) shall be conditioned on stockholder approval no later than the Company’s annual stockholder meeting for 2026 of an amendment to the Plan increasing the number of shares of the Company’s common stock available for issuance under the Plan, and if such stockholder approval is not obtained, the Contingent Option will be forfeited without consideration. The Options will vest as to 25% of the shares subject to the Options on the first anniversary of the Effective Date and as to an additional 6.25% of such shares upon your completing each three months of continuous service to the Company thereafter. In all respects, the Options will be governed by and subject to the terms of the Plan and a separate stock option agreement to be entered into between you and the Company. Further, for sake of clarity, any Company stock options or restricted stock units issued to you during your employment with the Company prior to signing this letter will continue to vest in accordance with the terms of the applicable stock option award agreement or restricted stock unit award agreement executed by you and the Company and remain subject to potential accelerated vesting as provided in the Employment Agreement.
Retention Bonus. The Company will pay you a one-time retention bonus in the amount of $230,000 (the “Retention Bonus”), payable with your first Company paycheck that occurs at least five (5) days after the Effective Date. If you voluntarily terminate your employment with the Company without Good Reason or the Company terminates your employment for Cause, in each case, before December 31, 2026, you agree to repay the Company within thirty (30) days after your final day of employment the amount of the Retention Bonus net of taxes withheld by the Company upon its payment to you. You further agree that the Company will be entitled (but not required) to deduct any such repayment amount from the after-tax amount of any payments owed by the Company to you, subject to applicable law.
Severance. As of the Effective Date, **** Section 4(b)(i) of the Employment Agreement is amended and restated in its entirety to read as follows: “(i) an amount in cash equal to the product of (x) 1.0 times (y) the Annual Base Salary, payable in the form of salary continuation in regular installments over the 12-month period following the date of Executive’s Separation from Service (the “Severance Period”) in accordance with the Company’s normal payroll practices;”.
Change in Control Severance. As of the Effective Date, Section 4(c)(ii) of the Employment Agreement is amended and restated in its entirety to read as follows: “(ii) an amount in cash equal to the product of (x) 1.0 times (y) the Target Bonus, payable in a lump sum within thirty (30) days following the later of Executive’s Separation from Service and the date of a Change in Control; and”.
Good Reason. As of the Effective Date, **** clause (ii) of Section 7(f) of the Employment Agreement is amended and restated in its entirety to read as follows: “(ii) a material decrease in Executive’s authority or areas of responsibility as are commensurate with Executive’s title or positions, including Executive ceasing to report directly to the chief executive officer of the Company’s ultimate parent company following a Change in Control (or of the Company if there is no such parent entity),”.

Proprietary Information Agreement; Company Policies. Prior to the Effective Date, you executed and delivered to the Company an Employee Non-Competition, Non-Solicitation, Confidentiality and Assignment Agreement (the “Proprietary InformationAgreement”). You acknowledge and agree that you continue to be bound by the existing terms of the Proprietary Information Agreement, and nothing in this Agreement affects or modifies the terms of the Proprietary Information Agreement. You acknowledge that the provisions of the Proprietary Information Agreement will survive the termination of your employment for the periods set forth in the Proprietary Information Agreement.
At-Will Employment. It is understood that you are an “at-will” employee. You are not being offered employment for a definite period of time, and either you or the Company may terminate the employment relationship at any time and for any reason in accordance with the terms of the Employment Agreement.
Taxes. All forms of compensation referred to in this offer letter are subject to reduction to reflect applicable withholding and payroll taxes and other deductions required by law.
Assignment. Neither you nor the Company may make any assignment of this letter or any interest in it, by operation of law or otherwise, without the prior written consent of the other; provided, however, that the Company may assign its rights and obligations under this letter (including the Proprietary Information Agreement) without your consent to any affiliate or to any person or entity with whom the Company shall hereafter effect a reorganization, consolidate with, or merge into or to whom it transfers all or substantially all of its properties or assets. This letter shall inure to the benefit of and be binding upon you and the Company, and each of your and its respective successors, executors, administrators, heirs and permitted assigns.
Miscellaneous. This letter may not be modified or amended, and no breach shall be deemed to be waived, except by a written agreement signed by you and an authorized officer of the Company. The headings and captions in this letter are for convenience only and in no way define or describe the scope or content of any provision of this letter. This letter may be executed in counterparts, each of which shall be an original and all of which together shall constitute one and the same instrument.

Other Terms. In making this offer, the Company understands, and in accepting it you represent, that you are not under any obligation to any person, firm, or corporation which would prevent, limit, or impair in any way the performance by you of your duties as an employee of the Company.

[Signature Page Follows]

Please indicate your acceptance of and agreement to this letter by returning a signed copy of this letter to the undersigned within seven (7) days of the date hereof, after which time the Company’s offer to enter into this letter will automatically expire.

Very truly yours,
SERES THERAPEUTICS, INC.
By:	/s/ Marella Thorell
Marella Thorell
Chief Financial Officer
Accepted and Agreed:
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/s/ Kelly M. Brady
Kelly M. Brady

[Signature Page toEmployment Letter Agreement]

Exhibit A

Amended and Restated Employment Agreement

[Attached]

AMENDED AND RESTATED EMPLOYMENT AGREEMENT

This Amended and Restated Employment Agreement (this “Agreement”), dated as of the date of last signature below (the “Effective Date”), is made by and between Seres Therapeutics, Inc., a Delaware corporation (together with any successor thereto, the “Company”), and Kelly Brady (“Executive”) (collectively referred to as the “Parties” or individually referred to as a “Party”).

RECITALS

A.	It is the desire of the Company to assure itself of the services of Executive as of the Effective Date and<br>thereafter by entering into this Agreement, which shall supersede and replace any prior employment arrangement, including, but not limited to, the Employment Agreement, dated as of August 16, 2023 by and between the Company and Executive (the<br>“Prior Agreement”).
B.	Executive and the Company mutually desire that Executive continue to be employed by the Company on the terms<br>herein provided.
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AGREEMENT

NOW, THEREFORE, in consideration of the foregoing and of the respective covenants and agreements set forth below, the Parties hereto agree as follows:

1.	Employment.

(a) General. Effective as of the Effective Date, Executive shall remain in the employ of the Company, for the period and in the positions set forth in this Section 1, and subject to the other terms and conditions herein provided.

(b) At-Will Employment. The Company and Executive acknowledge that Executive’s employment is and shall continue to be at-will, as defined under applicable law, and that Executive’s employment with the Company may be terminated by either Party at any time for any or no reason (subject to the notice requirements of Section 3(b)). This “at-will” nature of Executive’s employment shall remain unchanged during Executive’s tenure as an employee and may not be changed, except in an express writing signed by Executive and a duly authorized officer of the Company. If Executive’s employment terminates for any reason, Executive shall not be entitled to any payments, benefits, damages, award or compensation other than as provided in this Agreement or otherwise agreed to in writing by the Company or as provided by applicable law. The term of this Agreement (the “Term”) shall commence on the Effective Date and end on the date this Agreement is terminated under Section 3.

(c) Positions and Duties. During the Term, Executive shall serve as Senior Vice President, Clinical Development of the Company, initially reporting directly to the Chief Executive Officer (“Supervisor” or “CEO”) of the Company, with such responsibilities, duties and authority normally associated with such positions and as may from time to time be assigned to Executive by the Supervisor or such other Company officer may determine. Executive shall

devote substantially all of Executive’s working time and efforts to the business and affairs of the Company (which shall include service to its affiliates, if applicable) and shall not engage in outside business activities (including serving on outside boards or committees) without the consent of the CEO, provided that Executive shall be permitted to (i) manage Executive’s personal, financial and legal affairs, (ii) participate in trade associations, and (iii) serve on the board of directors of not-for-profit or tax-exempt charitable organizations, in each case, subject to compliance with this Agreement and provided that such activities do not materially interfere with Executive’s performance of Executive’s duties and responsibilities hereunder. Executive agrees to observe and comply with the rules and policies of the Company as adopted by the Company from time to time, in each case as amended from time to time, as set forth in writing, and as delivered or made available to Executive (each, a “Policy”).

2.	Compensation and Related Matters.

(a) Annual Base Salary. During the Term, Executive shall receive a base salary at a rate of $414,300 per annum, which shall be paid in accordance with the customary payroll practices of the Company and shall be pro-rated for partial years of employment. Such annual base salary shall be reviewed (and may be adjusted) from time to time by the Company (such annual base salary, as it may be adjusted from time to time, the “Annual Base Salary”).

(b) Bonus. During the Term, Executive will be eligible to participate in an annual incentive program established by the Board of Directors of the Company or an authorized committee of the Board (in either case, the “Board”). Executive’s annual incentive compensation under such incentive program (the “Annual Bonus”) shall be targeted at 35% of Executive’s Annual Base Salary (such target, as may be adjusted by the Board from time to time, the “Target Bonus”). The Annual Bonus payable under the incentive program shall be based on the achievement of performance goals to be determined by the Board and may be pro-rated for any partial year of employment. The payment of any Annual Bonus pursuant to the incentive program shall be subject to Executive’s continued employment with the Company through the date of payment, except as otherwise provided in Section 4(b).

(c) Benefits. During the Term, Executive shall be eligible to participate in employee benefit plans, programs and arrangements of the Company (including medical, dental and 401(k) plans), subject to the terms and eligibility requirements thereof and as such plans, programs and arrangements may be amended or in effect from time to time. In no event shall Executive be eligible to participate in any severance plan or program of the Company, except as set forth in Section 4 of this Agreement.

(d) Vacation. During the Term, Executive shall be entitled to paid personal leave in accordance with the Company’s Policies. Any vacation shall be taken at the reasonable and mutual convenience of the Company and Executive.

(e) Business Expenses. During the Term, the Company shall reimburse Executive for all reasonable travel and other business expenses incurred by Executive in the performance of Executive’s duties to the Company in accordance with the Company’s expense reimbursement Policy.

(f) Key Person Insurance. At any time during the Term, the Company shall have the right to insure the life of Executive for the Company’s sole benefit. The Company shall have the right to determine the amount of insurance and the type of policy. Executive shall reasonably cooperate with the Company in obtaining such insurance by submitting to physical examinations, by supplying all information reasonably required by any insurance carrier, and by executing all necessary documents reasonably required by any insurance carrier, provided that any information provided to an insurance company or broker shall not be provided to the Company without the prior written authorization of Executive. Executive shall incur no financial obligation by executing any required document, and shall have no interest in any such policy.

(g) Equity. Subject to approval by the Board, the Company will grant Executive, under the Company’s 2015 Incentive Award Plan (the “Plan”), an award of 75,000 restricted stock units (the “RSUs”) under the Plan (subject to adjustment for corporate events as set forth in the Plan), which will vest 100% on September 30, 2025, subject to Executive’s continued service to the Company. In all respects, the RSUs will be governed by and subject to the terms of the Plan and a separate RSU award agreement to be entered into between Executive and the Company. Further, for sake of clarity, any stock options and RSUs issued to Executive during their employment with Company, prior to signing this Agreement, will continue to vest in accordance with the existing option and RSU agreements executed by Executive and Company.

(h) Retention Bonus. Executive will be paid a one-time retention bonus of $200,000 (the “Retention Bonus”), which shall be paid in two equal installments of $100,000 each on June 30, 2025 and December 30, 2025, subject to Executive’s continued service to the Company.

3.	Termination.

Executive’s employment hereunder and the Term may be terminated by the Company or Executive, as applicable, without any breach of this Agreement under the following circumstances and the Term will end on the Date of Termination:

(a) Circumstances.

(i) Death. Executive’s employment hereunder shall terminate upon Executive’s death.

(ii) Disability. If Executive has incurred a Disability, as defined below, the Company may terminate Executive’s employment.

(iii) Termination for Cause. The Company may terminate Executive’s employment for Cause, as defined below.

(iv) Termination without Cause. The Company may terminate Executive’s employment without Cause.

(v) Resignation from the Company for Good Reason. Executive may resign Executive’s employment with the Company for Good Reason, as defined below.

(vi) Resignation from the Company Without Good Reason. Executive may resign Executive’s employment with the Company for any reason other than Good Reason or for no reason.

(b) Notice of Termination. Any termination of Executive’s employment by the Company or by Executive under this Section 3 (other than termination pursuant to paragraph (a)(i)) shall be communicated by a written notice to the other Party hereto (i) indicating the specific termination provision in this Agreement relied upon, (ii) setting forth in reasonable detail the facts and circumstances claimed to provide a basis for termination of Executive’s employment under the provision so indicated, if applicable, and (iii) specifying a Date of Termination which, if submitted by Executive, shall be at least forty-five (45) days following the date of such notice (a “Notice of Termination”); provided, however, that in the event that Executive delivers a Notice of Termination to the Company, the Company may, in its sole discretion, change the Date of Termination to any date that occurs following the date of the Company’s receipt of such Notice of Termination and is prior to the date specified in such Notice of Termination but the termination will still be considered a resignation by Executive. A Notice of Termination submitted by the Company may provide for a Date of Termination on the date Executive receives the Notice of Termination, or any date thereafter elected by the Company in its sole discretion. The failure by the Company to set forth in the Notice of Termination any fact or circumstance which contributes to a showing of Cause shall not waive any right of the Company hereunder or preclude the Company from asserting such fact or circumstance in enforcing the Company’s rights hereunder.

(c) Company Obligations upon Termination. Upon termination of Executive’s employment pursuant to any of the circumstances listed in this Section 3, Executive (or Executive’s estate) shall be entitled to receive the sum of: (i) the portion of Executive’s Annual Base Salary earned through the Date of Termination, but not yet paid to Executive; (ii) any expense reimbursements owed to Executive pursuant to Section 2(e); and (iii) any amount accrued and arising from Executive’s participation in, or benefits accrued under any employee benefit plans, programs or arrangements, which amounts shall be payable in accordance with the terms and conditions of such employee benefit plans, programs or arrangements (collectively, the “Company Arrangements”). Except as otherwise expressly required by law (e.g., COBRA) or as specifically provided herein, all of Executive’s rights to salary, severance, benefits, bonuses and other compensatory amounts hereunder (if any) shall cease upon the termination of Executive’s employment hereunder. In the event that Executive’s employment is terminated by the Company for any reason, Executive’s sole and exclusive remedy shall be to receive the payments and benefits described in this Section 3(c) or Section 4, as applicable.

(d) Deemed Resignation. Upon termination of Executive’s employment for any reason, Executive shall be deemed to have resigned from all offices and directorships, if any, then held with the Company or any of its subsidiaries.

4.	Severance Payments.

(a) Termination for Cause, or Termination Upon Death, Disability or Resignation from the Company Without Good Reason. If Executive’s employment shall terminate as a result of Executive’s death pursuant to Section 3(a)(i) or Disability pursuant to Section 3(a)(ii), pursuant to Section 3(a)(iii) for Cause, or pursuant to Section 3(a)(vi) for Executive’s resignation from the Company without Good Reason, then Executive shall not be entitled to any severance payments or benefits, except as provided in Section 3(c).

(b) Termination without Cause, or Resignation from the Company for Good Reason. If Executive’s employment terminates without Cause pursuant to Section 3(a)(iv), or pursuant to Section 3(a)(v) due to Executive’s resignation for Good Reason, then, except as otherwise provided by Section 4(c) and subject to Executive signing on or before the 21^st^ day following Executive’s Separation from Service (as defined below), and not revoking, a release of claims substantially in the form attached as Exhibit A to this Agreement (the “Release”), and Executive’s continued compliance with Section 5, Executive shall receive, in addition to payments and benefits set forth in Section 3(c), the following:

(i) an amount in cash equal to the product of (x) 0.75 times (y) the Annual Base Salary, payable in the form of salary continuation in regular installments over the 9-month period following the date of Executive’s Separation from Service (the “Severance Period”) in accordance with the Company’s normal payroll practices;

(ii) to the extent unpaid as of the Date of Termination, an amount of cash equal to any Annual Bonus earned by Executive for the Company’s fiscal year prior to the fiscal year in which the Date of Termination occurs, as determined by the Board in its discretion based upon actual performance achieved, which Annual Bonus, if any, shall be paid to Executive in the fiscal year in which the Date of Termination occurs when bonuses for such prior fiscal year are paid in the ordinary course to actively employed senior executives of the Company; and

(iii) if Executive timely elects to receive continued medical, dental or vision coverage under one or more of the Company’s group healthcare plans pursuant to the Consolidated Omnibus Budget Reconciliation Act of 1985, as amended (“COBRA”), the Company shall directly pay, or reimburse Executive for, the COBRA premiums for Executive and Executive’s covered dependents under such plans during the period commencing on Executive’s Separation from Service and ending upon the earliest of (X) the last day of the Severance Period, (Y) the date that Executive and/or Executive’s covered dependents become no longer eligible for COBRA or (Z) the date Executive becomes eligible to receive healthcare coverage from a subsequent employer (and Executive agrees to promptly notify the Company of such eligibility). Notwithstanding the foregoing, if the Company determines in its sole discretion that it cannot provide the foregoing benefit without potentially violating applicable law (including, without limitation, Section 2716 of the Public Health Service Act) or incurring an excise tax, the Company shall in lieu thereof provide to Executive a taxable monthly payment in an amount equal to the monthly COBRA premium that Executive would be required to pay to continue Executive’s and Executive’s covered dependents’ group health coverage in effect on the Date of Termination (which amount shall be based on the premium for the first month of COBRA coverage), which payments shall be made regardless of whether Executive elects COBRA continuation coverage and shall commence in the month

following the month in which the Date of Termination occurs and shall end on the earlier of (X) the last day of the Severance Period, (Y) the date that Executive and/or Executive’s covered dependents become no longer eligible for COBRA or (Z) the date Executive becomes eligible to receive healthcare coverage from a subsequent employer (and Executive agrees to promptly notify the Company of such eligibility).

(c) Change in Control. In lieu of the payments and benefits set forth in Section 4(b), in the event Executive’s employment terminates without Cause pursuant to Section 3(a)(iv), or pursuant to Section 3(a)(v) due to Executive’s resignation for Good Reason, in either case, within 60 days prior to or 12 months following the date of a Change in Control, subject to Executive signing on or before the 21st day following Executive’s Separation from Service, and not revoking, the Release, and Executive’s continued compliance with Section 5, Executive shall receive the following:

(i) without duplication, the payments and benefits described in Section 4(b);

(ii) an amount in cash equal to the product of (x) 0.75 times (y) the Target Bonus, payable in a lump sum within thirty (30) days following the later of Executive’s Separation from Service and the date of a Change in Control; and

(iii) all unvested equity or equity-based awards held by Executive under any Company equity compensation plans that vest solely based on the passage of time shall immediately become 100% vested (and if the Date of Termination precedes the Change in Control, all such unvested awards shall remain outstanding and eligible to vest in accordance with this Section 4(c)(iii) if a Change Control occurs within 60 days after the Date of Termination, provided that in no event will any such award remain outstanding beyond the final expiration date of the award set forth in the documents governing such award), with any other equity or equity-based awards (including awards that vest in whole or in part based on the attainment of performance-vesting conditions) being governed by the terms of the applicable award agreement.

(iv) any remaining Retention Bonus installments due to Executive if a Termination without Cause or Change in Control occurs prior to the last Retention Bonus installment on December 30, 2025.

(d) Survival. Notwithstanding anything to the contrary in this Agreement, the provisions of Sections 5 through 9 will survive the termination of Executive’s employment and the termination of the Term.

5. Restrictive Covenants . Prior to the effectiveness of this Agreement, Executive has executed and delivered to the Company an Employee Non-Competition, Non-Solicitation, Confidentiality and Assignment Agreement (the “Proprietary Information Agreement”). Executive acknowledges and agrees that Executive continues to be bound by the existing terms of the Proprietary Information Agreement, and nothing in this Agreement affects or modifies the terms of the Proprietary Information Agreement. Executive acknowledges that the provisions of the Proprietary Information Agreement will survive the termination of Executive’s employment and the termination of the Term for the periods set forth in the Proprietary Information Agreement.

6.	Assignment and Successors.

The Company may assign its rights and obligations under this Agreement to any of its affiliates or to any successor to all or substantially all of the business or the assets of the Company (by merger or otherwise), and may assign or encumber this Agreement and its rights hereunder as security for indebtedness of the Company and its affiliates. This Agreement shall be binding upon and inure to the benefit of the Company, Executive and their respective successors, assigns, personal and legal representatives, executors, administrators, heirs, distributees, devisees, and legatees, as applicable. None of Executive’s rights or obligations may be assigned or transferred by Executive, other than Executive’s rights to payments hereunder, which may be transferred only by will or operation of law. Notwithstanding the foregoing, Executive shall be entitled, to the extent permitted under applicable law and applicable Company Arrangements, to select and change a beneficiary or beneficiaries to receive compensation hereunder following Executive’s death by giving written notice thereof to the Company.

7.	Certain Definitions.

(a) Cause. The Company shall have “Cause” to terminate Executive’s employment hereunder upon:

(i) Executive’s refusal to (A) substantially perform Executive’s duties with the Company (other than any such failure resulting from Executive’s Disability) or (B) comply with, in any material respect, any of the Company’s Policies;

(ii) the Board’s determination that Executive refused in any material respect to carry out or comply with any lawful and reasonable directive of the Board;

(iii) Executive’s material breach of a material provision of this Agreement;

(iv) Executive’s conviction, plea of no contest, plea of nolo contendere, or imposition of unadjudicated probation for any felony or crime involving moral turpitude;

(v) Executive’s unlawful use (including being under the influence) or possession of illegal drugs on the Company’s (or any of its affiliate’s) premises or while performing Executive’s duties and responsibilities under this Agreement; or

(vi) Executive’s commission of an act of fraud, embezzlement, misappropriation, willful misconduct, or breach of fiduciary duty against the Company or any of its affiliates;

provided, however, that Executive’s termination will not be considered for Cause unless and until (a) the Company has provided Executive, within 60 days of the Company’s knowledge of the occurrence of the facts and circumstances underlying the Cause event, written notice stating with reasonable specificity the applicable facts and circumstances underlying such finding of Cause and (b) in the case of alleged Cause under clause (i), (ii) or (iii) of the foregoing definition and to the extent the applicable condition or event is reasonably capable of being cured, Executive shall have failed to cure such condition or event within 30 days after the receipt of such notice.

(b) Change in Control. “Change in Control” shall have the meaning set forth in the version of the Seres Therapeutics, Inc. 2015 Incentive Award Plan in effect on the Effective Date.

(c) Code. “Code” shall mean the Internal Revenue Code of 1986, as amended, and the regulations and guidance promulgated thereunder.

(d) Date of Termination. “Date of Termination” shall mean (i) if Executive’s employment is terminated by Executive’s death, the date of Executive’s death; or (ii) if Executive’s employment is terminated pursuant to Section 3(a)(ii) – (vi) either the date indicated in the Notice of Termination or the date specified by the Company pursuant to Section 3(b), whichever is earlier.

(e) Disability. “Disability” shall mean, at any time the Company or any of its affiliates sponsors a long-term disability plan for the Company’s employees, “disability” as defined in such long-term disability plan for the purpose of determining a participant’s eligibility for benefits, provided, however, if the long-term disability plan contains multiple definitions of disability, “Disability” shall refer to that definition of disability which, if Executive qualified for such disability benefits, would provide coverage for the longest period of time. The determination of whether Executive has a Disability shall be made by the person or persons required to make disability determinations under the long-term disability plan. At any time the Company does not sponsor a long-term disability plan for its employees, “Disability” shall mean Executive’s inability to perform, with or without reasonable accommodation, the essential functions of Executive’s positions hereunder for a total of three months during any six-month period as a result of incapacity due to mental or physical illness as determined by a physician selected by the Company or its insurers and acceptable to Executive or Executive’s legal representative, with such agreement as to acceptability not to be unreasonably withheld or delayed. Any refusal by Executive to submit to a medical examination for the purpose of determining Disability shall be deemed to constitute conclusive evidence of Executive’s Disability.

(f) Good Reason. For the sole purpose of determining Executive’s right to severance payments and benefits as described above, Executive’s resignation will be for “Good Reason” if Executive resigns within ninety days after any of the following events, unless Executive consents to the applicable event: (i) a material decrease in Executive’s Annual Base Salary, (ii) a material decrease in Executive’s authority or areas of responsibility as are commensurate with Executive’s title or positions, which shall not include a determination by the Company’s CEO or the Supervisor that Executive will report to another Company officer as contemplated by Section 1(c), (iii) the Company’s material breach of a material provision of this Agreement or another written agreement with Executive or (iv) the relocation of Executive’s primary office to a location more than 50 miles from the Boston metropolitan area. Notwithstanding the foregoing, no Good Reason will have occurred unless and until Executive has: (a) provided the Company, within 60 days of Executive’s knowledge of the occurrence of the facts and circumstances underlying the Good Reason event, written notice stating with reasonable specificity the applicable facts and circumstances underlying such finding of Good Reason; (b) provided the Company with an opportunity to cure the same within 30 days after the receipt of such notice; and (c) the Company shall have failed to cure such condition within such 30 day period.

8.	Parachute Payments.

(a) Notwithstanding any other provisions of this Agreement or any Company equity plan or agreement, in the event that any payment or benefit by the Company or otherwise to or for the benefit of Executive, whether paid or payable or distributed or distributable pursuant to the terms of this Agreement or otherwise (all such payments and benefits, including the payments and benefits under Section 4(b) and Section 4(c) hereof, being hereinafter referred to as the “Total Payments”), would be subject (in whole or in part) to the excise tax imposed by Section 4999 of the Code (the “Excise Tax”), then the Total Payments shall be reduced (in the order provided in Section 8(b)) to the minimum extent necessary to avoid the imposition of the Excise Tax on the Total Payments, but only if (i) the net amount of such Total Payments, as so reduced (and after subtracting the net amount of federal, state and local income and employment taxes on such reduced Total Payments and after taking into account the phase out of itemized deductions and personal exemptions attributable to such reduced Total Payments), is greater than or equal to (ii) the net amount of such Total Payments without such reduction (but after subtracting the net amount of federal, state and local income and employment taxes on such Total Payments and the amount of the Excise Tax to which Executive would be subject in respect of such unreduced Total Payments and after taking into account the phase out of itemized deductions and personal exemptions attributable to such unreduced Total Payments).

(b) The Total Payments shall be reduced in the following order: (i) reduction on a pro-rata basis of any cash severance payments that are exempt from Section 409A of the Code (“Section 409A”), (ii) reduction on a pro-rata basis of any non-cash severance payments or benefits that are exempt from Section 409A, (iii) reduction on a pro-rata basis of any other payments or benefits that are exempt from Section 409A, and (iv) reduction of any payments or benefits otherwise payable to Executive on a pro-rata basis or such other manner that complies with Section 409A; provided, in case of clauses (ii), (iii) and (iv), that reduction of any payments attributable to the acceleration of vesting of Company equity awards shall be first applied to Company equity awards that would otherwise vest last in time.

(c) All determinations regarding the application of this Section 8 shall be made by an accounting firm or consulting group with experience in performing calculations regarding the applicability of Section 280G of the Code and the Excise Tax selected by the Company (the “Independent Advisors”). For purposes of determinations, no portion of the Total Payments shall be taken into account which, in the opinion of the Independent Advisors, (i) does not constitute a “parachute payment” within the meaning of Section 280G(b)(2) of the Code (including by reason of Section 280G(b)(4)(A) of the Code) or (ii) constitutes reasonable compensation for services actually rendered, within the meaning of Section 280G(b)(4)(B) of the Code, in excess of the “base amount” (as defined in Section 280G(b)(3) of the Code) allocable to such reasonable compensation. The costs of obtaining such determination and all related fees and expenses (including related fees and expenses incurred in any later audit) shall be borne by the Company.

(d) In the event it is later determined that a greater reduction in the Total Payments should have been made to implement the objective and intent of this Section 8, the excess amount shall be returned promptly by Executive to the Company.

9.	Miscellaneous Provisions.

(a) Governing Law. This Agreement shall be governed, construed, interpreted and enforced in accordance with its express terms, and otherwise in accordance with the substantive laws of the Commonwealth of Massachusetts without reference to the principles of conflicts of law of the Commonwealth of Massachusetts or any other jurisdiction that would result in the application of the laws of a jurisdiction other than the Commonwealth of Massachusetts, and where applicable, the laws of the United States.

(b) Validity. The invalidity or unenforceability of any provision or provisions of this Agreement shall not affect the validity or enforceability of any other provision of this Agreement, which shall remain in full force and effect.

(c) Notices. Any notice, request, claim, demand, document and other communication hereunder to any Party shall be effective upon receipt (or refusal of receipt) and shall be in writing and delivered personally or sent by facsimile or certified or registered mail, postage prepaid, as follows:

(i) If to the Company, the Chief Legal Officer at its headquarters,

(ii) If to Executive, at the last address that the Company has in its personnel records for Executive, or

(iii) at any other address as any Party shall have specified by notice in writing to the other Party.

(d) Counterparts. This Agreement may be executed in several counterparts, each of which shall be deemed to be an original, but all of which together will constitute one and the same Agreement. Signatures delivered by facsimile or PDF shall be deemed effective for all purposes.

(e) Entire Agreement. The terms of this Agreement, and the Proprietary Information Agreement incorporated herein by reference as set forth in Section 5, are intended by the Parties to be the final expression of their agreement with respect to the subject matter hereof and supersede all prior understandings and agreements, whether written or oral. The Parties further intend that this Agreement shall constitute the complete and exclusive statement of their terms and that no extrinsic evidence whatsoever may be introduced in any judicial, administrative, or other legal proceeding to vary the terms of this Agreement.

(f) Amendments; Waivers. This Agreement may not be modified, amended, or terminated except by an instrument in writing, signed by Executive and a duly authorized officer of Company. By an instrument in writing similarly executed, Executive or a duly authorized officer of the Company may waive compliance by the other Party with any specifically identified provision of this Agreement that such other Party was or is obligated to comply with or perform; provided, however, that such waiver shall not operate as a waiver of, or estoppel with respect to, any other or subsequent failure. No failure to exercise and no delay in exercising any right, remedy, or power hereunder will preclude any other or further exercise of any other right, remedy, or power provided herein or by law or in equity.

(g) No Inconsistent Actions. The Parties hereto shall not voluntarily undertake or fail to undertake any action or course of action inconsistent with the provisions or essential intent of this Agreement. Furthermore, it is the intent of the Parties hereto to act in a fair and reasonable manner with respect to the interpretation and application of the provisions of this Agreement.

(h) Construction. This Agreement shall be deemed drafted equally by both the Parties. Its language shall be construed as a whole and according to its fair meaning. Any presumption or principle that the language is to be construed against any Party shall not apply. The headings in this Agreement are only for convenience and are not intended to affect construction or interpretation. Any references to paragraphs, subparagraphs, sections or subsections are to those parts of this Agreement, unless the context clearly indicates to the contrary. Also, unless the context clearly indicates to the contrary, (i) the plural includes the singular and the singular includes the plural; (ii) “and” and “or” are each used both conjunctively and disjunctively; (iii) “any,” “all,” “each,” or “every” means “any and all,” and “each and every”; (iv) “includes” and “including” are each “without limitation”; (v) “herein,” “hereof,” “hereunder” and other similar compounds of the word “here” refer to the entire Agreement and not to any particular paragraph, subparagraph, section or subsection; and (vi) all pronouns and any variations thereof shall be deemed to refer to the masculine, feminine, neuter, singular or plural as the identity of the entities or persons referred to may require.

to the JAMS/Endispute rules and regulations) of the proceedings has been given to such Party. Each Party shall bear its own attorney’s fees and expenses; provided that the arbitrator may assess the prevailing Party’s fees and costs against the non-prevailing Party as part of the arbitrator’s award. The Parties agree to abide by all decisions and awards rendered in such proceedings. Such decisions and awards rendered by the arbitrator shall be final and conclusive. All such controversies, claims or disputes shall be settled in this manner in lieu of any action at law or equity; provided, however, that nothing in this subsection shall be construed as precluding the bringing of an action for injunctive relief or specific performance as provided in this Agreement or Proprietary Information Agreement. This dispute resolution process and any arbitration hereunder shall be confidential and neither any Party nor the neutral arbitrator shall disclose the existence, contents or results of such process without the prior written consent of all Parties, except where necessary or compelled in a court to enforce this arbitration provision or an award from such arbitration or otherwise in a legal proceeding. If JAMS/Endispute no longer exists or is otherwise unavailable, the Parties agree that the American Arbitration Association (“AAA”) shall administer the arbitration in accordance with its then-existing rules as modified by this subsection. In such event, all references herein to JAMS/Endispute shall mean AAA. Notwithstanding the foregoing, Executive and the Company each have the right to resolve any issue or dispute over intellectual property rights by court action instead of arbitration.

(j) Enforcement. If any provision of this Agreement is held to be illegal, invalid or unenforceable under present or future laws effective during the Term, such provision shall be fully severable; this Agreement shall be construed and enforced as if such illegal, invalid or unenforceable provision had never comprised a portion of this Agreement; and the remaining provisions of this Agreement shall remain in full force and effect and shall not be affected by the illegal, invalid or unenforceable provision or by its severance from this Agreement. Furthermore, in lieu of such illegal, invalid or unenforceable provision there shall be added automatically as part of this Agreement a provision as similar in terms to such illegal, invalid or unenforceable provision as may be possible and be legal, valid and enforceable.

(k) Withholding. The Company shall be entitled to withhold from any amounts payable under this Agreement any federal, state, local or foreign withholding or other taxes or charges which the Company is required to withhold. The Company shall be entitled to rely on the advice of counsel if any questions as to the amount or requirement of withholding shall arise.

(l) Section 409A.

(i) General. The intent of the Parties is that the payments and benefits under this Agreement comply with or be exempt from Section 409A and, accordingly, to the maximum extent permitted, this Agreement shall be interpreted to be in compliance therewith.

(ii) Separation from Service. Notwithstanding anything in this Agreement to the contrary, any compensation or benefits payable under this Agreement that is considered nonqualified deferred compensation under Section 409A and is designated under this Agreement as payable upon Executive’s termination of employment shall be payable only upon Executive’s “separation from service” with the Company within the

meaning of Section 409A (a “Separation from Service”) and, except as provided below, any such compensation or benefits described in Section 4 shall not be paid, or, in the case of installments, shall not commence payment, until the thirtieth (30th) day following Executive’s Separation from Service (the “First Payment Date”). Any installment payments that would have been made to Executive during the thirty (30) day period immediately following Executive’s Separation from Service but for the preceding sentence shall be paid to Executive on the First Payment Date and the remaining payments shall be made as provided in this Agreement.

(iii) Specified Employee. Notwithstanding anything in this Agreement to the contrary, if Executive is deemed by the Company at the time of Executive’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 Executive is entitled under this Agreement is required in order to avoid a prohibited distribution under Section 409A, such portion of Executive’s benefits shall not be provided to Executive prior to the earlier of (i) the expiration of the six-month period measured from the date of Executive’s Separation from Service with the Company or (ii) the date of Executive’s death. Upon the first business day following the expiration of the applicable Section 409A period, all payments deferred pursuant to the preceding sentence shall be paid in a lump sum to Executive (or Executive’s estate or beneficiaries), and any remaining payments due to Executive under this Agreement shall be paid as otherwise provided herein.

(iv) Expense Reimbursements. To the extent that any reimbursements under this Agreement are subject to Section 409A, (i) any such reimbursements payable to Executive shall be paid to Executive no later than December 31 of the year following the year in which the expense was incurred; (ii) Executive shall submit Executive’s reimbursement request promptly following the date the expense is incurred, (iii) the amount of expenses reimbursed in one year shall not affect the amount eligible for reimbursement in any subsequent year, other than medical expenses referred to in Section 105(b) of the Code, and (iv) Executive’s right to reimbursement under this Agreement will not be subject to liquidation or exchange for another benefit.

(v) Installments. Executive’s right to receive any installment payments under this Agreement, including without limitation any continuation salary payments that are payable on Company payroll dates, shall be treated as a right to receive a series of separate payments and, accordingly, each such installment payment shall at all times be considered a separate and distinct payment as permitted under Section 409A. Except as otherwise permitted under Section 409A, no payment hereunder shall be accelerated or deferred unless such acceleration or deferral would not result in additional tax or interest pursuant to Section 409A.

10.	Executive Acknowledgement.

Executive acknowledges that Executive has read and understands this Agreement, is fully aware of its legal effect, has not acted in reliance upon any representations or promises made by the Company other than those contained in writing herein, and has entered into this Agreement freely based on Executive’s own judgment.

[Signature Page Follows]

IN WITNESS WHEREOF, the Parties have executed this Agreement on the date and year first above written.

SERES THERAPEUTICS, INC.
By:	/s/ Thomas J. DesRosier
	Name: Thomas J. DesRosier
	Title: EVP, Chief Legal Officer
/s/ Kelly Brady
Kelly Brady

EXHIBIT A

Separation Agreement and Release

This Separation Agreement and Release (“Agreement”) is made by and between Kelly Brady (“Executive”) and Seres Therapeutics, Inc. (the “Company”) (collectively referred to as the “Parties” or individually referred to as a “Party”). Capitalized terms used but not defined in this Agreement shall have the meanings set forth in the Employment Agreement (as defined below).

WHEREAS, the Parties have previously entered into that certain Employment Agreement, dated as of ___________, 2025 (the “Employment Agreement”); and

WHEREAS, in connection with Executive’s termination of employment with the Company or a subsidiary or affiliate of the Company effective ________, 20__, the Parties wish to resolve any and all disputes, claims, complaints, grievances, charges, actions, petitions, and demands that Executive may have against the Company and any of the Releasees as defined below, including, but not limited to, any and all claims arising out of or in any way related to Executive’s employment with or separation from the Company or its subsidiaries or affiliates but, for the avoidance of doubt, nothing herein will be deemed to release any rights or remedies in connection with Executive’s ownership of vested equity securities of the Company or Executive’s right to indemnification by the Company or any of its affiliates pursuant to contract or applicable law (collectively, the “Retained Claims”).

NOW, THEREFORE, in consideration of the severance payments and benefits described in Section 4 of the Employment Agreement, which, pursuant to the Employment Agreement, are conditioned on Executive’s execution and non-revocation of this Agreement, and in consideration of the mutual promises made herein, the Company and Executive hereby agree as follows:

Severance Payments; Salary and Benefits. The Company agrees to provide Executive with the severance payments and benefits described in Section 4(b) and/or Section 4(c) of the Employment Agreement, payable at the times set forth in, and subject to the terms and conditions of, the Employment Agreement. In addition, to the extent not already paid, and subject to the terms and conditions of the Employment Agreement, the Company shall pay or provide to Executive all other payments or benefits described in Section 3(c) of the Employment Agreement, subject to and in accordance with the terms thereof.
Release of Claims. Executive agrees that, other than with respect to the Retained Claims, the foregoing consideration represents settlement in full of all outstanding obligations owed to Executive by the Company, any of its direct or indirect subsidiaries and affiliates, and any of its or their respective current and former officers, directors, equity holders, managers, employees, agents, investors, attorneys, shareholders, administrators, affiliates, benefit plans, plan administrators, insurers, trustees, divisions, and subsidiaries and predecessor and successor corporations and assigns (collectively, the “Releasees”). Executive, on Executive’s own behalf and on behalf of any of Executive’s affiliated companies or entities and any of Executive’s or their respective heirs, family members, executors, agents, and assigns, other than with respect to the Retained Claims, hereby and forever releases the Releasees from, and agrees not to sue concerning, or in any manner to institute, prosecute, or pursue, any claim, complaint, charge,

duty, obligation, or cause of action relating to any matters of any kind, whether presently known or unknown, suspected or unsuspected, that Executive may possess against any of the Releasees arising from any omissions, acts, facts, or damages that have occurred up until and including the date Executive signs this Agreement, including, without limitation:

(a) any and all claims relating to or arising from Executive’s employment or service relationship with the Company or any of its direct or indirect subsidiaries or affiliates and the termination of that relationship;

(b) any and all claims relating to, or arising from, Executive’s right to purchase, or actual purchase of any shares of stock or other equity interests of the Company or any of its affiliates, including, without limitation, any claims for fraud, misrepresentation, breach of fiduciary duty, breach of duty under applicable state corporate law, and securities fraud under any state or federal law;

(c) any and all claims for wrongful discharge of employment; termination in violation of public policy; discrimination; harassment; retaliation; breach of contract, both express and implied; breach of covenant of good faith and fair dealing, both express and implied; promissory estoppel; negligent or intentional infliction of emotional distress; fraud; negligent or intentional misrepresentation; negligent or intentional interference with contract or prospective economic advantage; unfair business practices; defamation; libel; slander; negligence; personal injury; assault; battery; invasion of privacy; false imprisonment; conversion; and disability benefits;

(d) any and all claims for violation of any federal, state, or municipal statute, including, but not limited to, Title VII of the Civil Rights Act of 1964; the Civil Rights Act of 1991; the Rehabilitation Act of 1973; the Americans with Disabilities Act of 1990; the Equal Pay Act; the Fair Credit Reporting Act; the Age Discrimination in Employment Act of 1967; the Older Workers Benefit Protection Act; the Employee Retirement Income Security Act of 1974; the Worker Adjustment and Retraining Notification Act; the Family and Medical Leave Act; and the Sarbanes-Oxley Act of 2002;

(e) any and all claims for violation of the federal or any state constitution;

(f) any and all claims arising out of any other laws and regulations relating to employment or employment discrimination;

(g) any claim for any loss, cost, damage, or expense arising out of any dispute over the non-withholding or other tax treatment of any of the proceeds received by Executive as a result of this Agreement;

(h) any and all claims arising out of the wage and hour and wage payments laws and regulations of the state or states in which Executive has provided service to the Company or any of its affiliates (including, without limitation, the Massachusetts Payment of Wages Law); and

(i) any and all claims for attorneys’ fees and costs.

Executive agrees that the release set forth in this section shall be and remain in effect in all respects as a complete general release as to the matters released. This release does not release claims that cannot be released as a matter of law, including, but not limited to, Executive’s right to report possible violations of federal law or regulation to any governmental agency or entity in accordance with the provisions of and rules promulgated under Section 21F of the Securities Exchange Act of 1934 or Section 806 of the Sarbanes-Oxley Act of 2002, or any other whistleblower protection provisions of state or federal law or regulation (including Executive’s right to receive an award for information provided to any such government agencies), Executive’s right to file a charge with or participate in a charge by the Equal Employment Opportunity Commission, or any other local, state, or federal administrative body or government agency that is authorized to enforce or administer laws related to employment, against the Company (with the understanding that Executive’s release of claims herein bars Executive from recovering monetary or other individual relief from the Company or any Releasee) in connection with any charge, investigation or proceeding, or any related complaint or lawsuit, filed by Executive or by anyone else on Executive’s behalf before the federal Equal Employment Opportunity Commission or a comparable state or local agency), claims for unemployment compensation or any state disability insurance benefits pursuant to the terms of applicable state law, claims to continued participation in certain of the Company’s group benefit plans pursuant to the terms and conditions of COBRA, claims to any benefit entitlements vested as the date of separation of Executive’s employment, pursuant to written terms of any employee benefit plan of the Company or its affiliates and Executive’s right under applicable law, and any Retained Claims. This release further does not release claims for breach of Section 3(c), Section 4(b) or Section 4(c) of the Employment Agreement.

Acknowledgment of Waiver of Claims under ADEA. Executive understands and acknowledges that Executive is waiving and releasing any rights Executive may have under the Age Discrimination in Employment Act of 1967 (“ADEA”), and that this waiver and release is knowing and voluntary. Executive understands and agrees that this waiver and release does not apply to any rights or claims that may arise under the ADEA after the date Executive signs this Agreement. Executive understands and acknowledges that the consideration given for this waiver and release is in addition to anything of value to which Executive was already entitled. Executive further understands and acknowledges that Executive has been advised by this writing that: (a) Executive should consult with an attorney prior to executing this Agreement; (b) Executive has 21 days within which to consider this Agreement, and the Parties expressly agree that such time period to review this Agreement shall not be extended upon any material or immaterial changes to this Agreement; (c) Executive has 7 business days following Executive’s execution of this Agreement to revoke this Agreement pursuant to written notice to the Chief Legal Officer of the Company; (d) this Agreement shall not be effective until after the revocation period has expired; and (e) nothing in this Agreement prevents or precludes Executive from challenging or seeking a determination in good faith of the validity of this waiver under the ADEA, nor does it impose any condition precedent, penalties, or costs for doing so, unless specifically authorized by federal law. In the event Executive signs this Agreement and returns it to the Company in less than the 21 day period identified above, Executive hereby acknowledges that Executive has freely and voluntarily chosen to waive the time period allotted for considering this Agreement.
Post-Termination Obligations. Executive reaffirms Executive’s continuing obligations under the Proprietary Information Agreement between Executive and the Company dated as of [_________], and, without limiting the foregoing, Executive remakes the non-competition covenants set forth in the Proprietary Information Agreement as if set forth herein. In addition, Executive agrees to refrain from Disparaging (as defined below) the Company and its affiliates, including their respective services, technologies, practices, directors and officers.

The Company agrees to instruct its officers and directors to refrain from Disparaging Executive. Nothing in this Section shall preclude any Party from making truthful statements that are reasonably necessary to comply with applicable law, regulation or legal process, or to defend or enforce a Party’s rights under this Agreement or the Employment Agreement. For purposes of this Agreement, “Disparaging” means making remarks, comments or statements, whether written or oral, that impugn the character, integrity, reputation or abilities of the individual or entity being disparaged.

Severability. In the event that any provision or any portion of any provision hereof or any surviving agreement made a part hereof becomes or is declared by a court of competent jurisdiction or arbitrator to be illegal, unenforceable, or void, this Agreement shall continue in full force and effect without said provision or portion of provision.
No Oral Modification. This Agreement may only be amended in a writing signed by Executive and a duly authorized officer of the Company.
Governing Law; Dispute Resolution. This Agreement shall be subject to the provisions of Sections 9(a), 9(c) and 9(i) of the Employment Agreement.
Effective Date. Executive has seven business days after Executive signs this Agreement to revoke it and this Agreement will become effective upon the expiration of such seven business day period, so long as it has been signed by the Parties and has not been revoked by Executive before that date.
Protected Disclosures. In accordance with 18 U.S.C. §1833, notwithstanding anything to the contrary in this Agreement, the Employment Agreement, the Proprietary Information Agreement or any other agreement between Executive and the Company or any of its subsidiaries in effect as of the date Executive receives this Agreement (together, the “Subject Documents”): (a) Executive will not be in breach of the Subject Documents, 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 Executive files a lawsuit for retaliation by the Company for reporting a suspected violation of law, Executive may disclose the trade secret to Executive’s attorney, and may use the trade secret information in the court proceeding, if Executive files any document containing the trade secret under seal, and does not disclose the trade secret, except pursuant to court order. Furthermore, the Parties agree that nothing in the Subject Documents prohibits Executive from (i) communicating directly with, cooperating with, or providing information to, or receiving financial awards from, any federal, state or local government agency, including without limitation the U.S. Securities and Exchange Commission, the U.S. Commodity Futures Trading Commission, the U.S. Department of Justice, the U.S. Equal Employment Opportunity Commission, or the U.S. National Labor Relations Board, without notifying or seeking permission from the Company or (ii) discussing or disclosing information about unlawful acts in the workplace, such as harassment or discrimination based on a protected characteristic or any other conduct that Employee has reason to believe is unlawful.
Voluntary Execution of Agreement. Executive understands and agrees that Executive executed this Agreement voluntarily, without any duress or undue influence on the part or behalf of the Company or any third party, with the full intent of releasing all of Executive’s claims against the Company and any of the other Releasees. Executive acknowledges that: (a) Executive has read this Agreement; (b) Executive has not relied upon any representations or statements made by the Company that are not specifically set forth in this Agreement; (c) Executive has been represented in the preparation, negotiation, and execution of this Agreement by legal counsel of Executive’s own choice or has elected not to retain legal counsel; (d) Executive understands the terms and consequences of this Agreement and of the releases it contains; and (e) Executive is fully aware of the legal and binding effect of this Agreement.

IN WITNESS WHEREOF, the Parties have executed this Agreement on the respective dates set forth below.

Dated:
	Kelly<br>Brady
	SERES THERAPEUTICS, INC.
Dated:	By:
	Name:<br> <br>Title:

EX-10.2

Exhibit 10.2

Seres Therapeutics, Inc.

101 Cambridge Park Drive

Cambridge, Massachusetts 02140

March 2, 2026

Matthew Henn, Ph.D.

By Email Delivery

Dear Matt,

**Employment Agreement.**The terms of the Second Amended and Restated Employment Agreement between you and the Company in effect on the date hereof and attached hereto as Exhibit A (the “Employment Agreement”) will remain in effect and continue to govern the terms of your employment except as provided in this letter. Capitalized terms used but not defined in this letter have the meaning provided in the Employment Agreement.
Position; Effective Date. Commencing on the Effective Date, you will serve as the Company’s President and Chief Scientific Officer. In this capacity you will initially report to Richard N. Kender, the Company’s Executive Chair. As of the Effective Date, references in the Employment Agreement to the CEO shall be deemed to refer to the Company’s Chief Executive Officer or the Company’s Executive Chair. For the avoidance of doubt, neither the change in your reporting to the Executive Chair as of the Effective Date nor a subsequent change in your reporting from the Executive Chair to the Company’s Chief Executive Officer will by itself be considered Good Reason under the Employment Agreement.
Annual BaseSalary; Work Location. Your Annual Base Salary for this position will be at the rate of $505,000 per year. Your Annual Base Salary will be paid in installments in accordance with the Company’s payroll practices and procedures as in effect from time to time and will be prorated for any partial period of employment. Your normal place of work will be the Company’s offices in Cambridge, Massachusetts.
Annual Target Bonus. As of the Effective Date, your Target Bonus will be 45% of your Annual Base Salary, prorated for any partial year of employment. The actual amount of any Annual Bonus will be determined by the Company’s Board of Directors or an authorized committee thereof (the “Board”) in its discretion, taking into consideration both the Company’s performance and your individual performance. The payment of any Annual Bonus will be subject to your continued employment with the Company through the date of payment, except as otherwise provided in Section 4 of the Employment Agreement.
Equity Award. Subject to approval by the Board, the Company will grant you options (the “Options”) under the Company’s 2025 Incentive Award Plan (the “Plan”) to purchase 100,000 shares of the Company’s common stock (subject to adjustment for corporate events as set forth in the Plan) at an exercise price per share equal to the per share fair market value of the Company’s common stock on the date of grant, as determined in accordance with the Plan, provided that 25% of the Options (the “ContingentOption”) shall be conditioned on stockholder approval no later than the Company’s annual stockholder meeting for 2026 of an amendment to the Plan increasing the number of shares of the Company’s common stock available for issuance under the Plan, and if such stockholder approval is not obtained, the Contingent Option will be forfeited without consideration. The Options will vest as to 25% of the shares subject to the Options on the first anniversary of the Effective Date and as to an additional 6.25% of such shares upon your completing each three months of continuous service to the Company thereafter. In all respects, the Options will be governed by and subject to the terms of the Plan and a separate stock option agreement to be entered into between you and the Company. Further, for sake of clarity, any Company stock options or restricted stock units issued to you during your employment with the Company prior to signing this letter will continue to vest in accordance with the terms of the applicable stock option award agreement or restricted stock unit award agreement executed by you and the Company and remain subject to potential accelerated vesting as provided in the Employment Agreement.
Retention Bonus. The Company will pay you a one-time retention bonus in the amount of $230,000 (the “Retention Bonus”), payable with your first Company paycheck that occurs at least five days after the Effective Date. If you voluntarily terminate your employment with the Company without Good Reason or the Company terminates your employment for Cause, in each case, before December 31, 2026, you agree to repay the Company within thirty days after your final day of employment the amount of the Retention Bonus net of taxes withheld by the Company upon its payment to you. You further agree that the Company will be entitled (but not required) to deduct any such repayment amount from the after-tax amount of any payments owed by the Company to you, subject to applicable law.
Proprietary Information Agreement; Company Policies. Prior to the Effective Date, you executed and delivered to the Company an Employee Non-Competition, Non-Solicitation, Confidentiality and Assignment Agreement (the “Proprietary Information Agreement”). You acknowledge and agree that you continue to be bound by the existing terms of the Proprietary Information Agreement, and nothing in this Agreement affects or modifies the terms of the Proprietary Information Agreement. You acknowledge that the provisions of the Proprietary Information Agreement will survive the termination of your employment for the periods set forth in the Proprietary Information Agreement.
At-Will Employment. It is understood that you are an “at-will” employee. You are not being offered employment for a definite period of time, and either you or the Company may terminate the employment relationship at any time and for any reason in accordance with the terms of the Employment Agreement.
Taxes. All forms of compensation referred to in this offer letter are subject to reduction to reflect applicable withholding and payroll taxes and other deductions required by law.

Assignment. Neither you nor the Company may make any assignment of this letter or any interest in it, by operation of law or otherwise, without the prior written consent of the other; provided, however, that the Company may assign its rights and obligations under this letter (including the Proprietary Information Agreement) without your consent to any affiliate or to any person or entity with whom the Company shall hereafter effect a reorganization, consolidate with, or merge into or to whom it transfers all or substantially all of its properties or assets. This letter shall inure to the benefit of and be binding upon you and the Company, and each of your and its respective successors, executors, administrators, heirs and permitted assigns.
Miscellaneous. This letter may not be modified or amended, and no breach shall be deemed to be waived, except by a written agreement signed by you and an authorized officer of the Company. The headings and captions in this letter are for convenience only and in no way define or describe the scope or content of any provision of this letter. This letter may be executed in counterparts, each of which shall be an original and all of which together shall constitute one and the same instrument.
OtherTerms. In making this offer, the Company understands, and in accepting it you represent, that you are not under any obligation to any person, firm, or corporation which would prevent, limit, or impair in any way the performance by you of your duties as an employee of the Company.

[Signature Page Follows]

Please indicate your acceptance of and agreement to this letter by returning a signed copy of this letter to the undersigned within seven days of the date hereof, after which time the Company’s offer to enter into this letter will automatically expire.

Very truly yours,
SERES THERAPEUTICS, INC.
By:	/s/ Marella Thorell
Marella Thorell
Chief Financial Officer
Accepted and Agreed:
---
/s/ Matthew Henn, Ph.D.
Matthew Henn, Ph.D.

[Signature Page to Employment Letter Agreement]

Exhibit A

Second Amended and Restated Employment Agreement

[Attached]

SECOND AMENDED AND RESTATED EMPLOYMENT AGREEMENT

This Second Amended and Restated Employment Agreement (this “Agreement”), dated as of January 29, 2021 (the “Effective Date”), is made by and between Seres Therapeutics, Inc., a Delaware corporation (together with any successor thereto, the “Company”), and Matthew R. Henn, Ph.D. (“Executive”) (collectively referred to as the “Parties” or individually referred to as a “Party”).

RECITALS

A.	It is the desire of the Company to assure itself of the services of Executive as of the Effective Date and<br>thereafter by entering into this Agreement, which shall supersede and replace any prior employment arrangement, including, but not limited to, the Amended and Restated Employment Agreement, dated as of March 25, 2019, by and between the Company<br>and Executive, as amended (the “Prior Agreement”).
B.	Executive and the Company mutually desire that Executive provide services to the Company on the terms herein<br>provided.
---	---

It is the desire of the Company to assure itself of the services of Executive as of the Effective Date and<br>thereafter by entering into this Agreement, which shall supersede and replace any prior employment arrangement, including, but not limited to, the Amended and Restated Employment Agreement, dated as of March 25, 2019, by and between the Company<br>and Executive, as amended (the “Prior Agreement”).

Executive and the Company mutually desire that Executive provide services to the Company on the terms herein<br>provided.

---

AGREEMENT

NOW, THEREFORE, in consideration of the foregoing and of the respective covenants and agreements set forth below, the Parties hereto agree as follows:

1. Employment.

(a) General. Effective as of the Effective Date, the Company shall continue to employ Executive and Executive shall remain in the employ of the Company, for the period and in the positions set forth in this Section 1, and subject to the other terms and conditions herein provided.

(c) Positions and Duties. During the Term, Executive shall serve as Executive Vice President and Chief Scientific Officer of the Company, initially reporting directly to the Chief Executive Officer of the Company (the “CEO”) with such responsibilities, duties and authority normally associated with such positions and as may from time to time be assigned to Executive by the CEO. Executive shall devote substantially all of Executive’s working time and efforts to the business and affairs of the Company (which shall include service to its affiliates, if applicable) and shall not engage in outside business activities (including serving on outside boards or committees) without the consent of the CEO, provided that Executive shall be permitted to (i) manage Executive’s personal, financial and legal affairs, (ii) participate in trade associations, and (iii) serve on the board of directors of not-for-profit or tax-exempt charitable organizations, in each case, subject to compliance with this Agreement and provided that such activities do not materially interfere with Executive’s performance of Executive’s duties and responsibilities hereunder. Executive agrees to observe and comply with the rules and policies of the Company as adopted by the Company from time to time, in each case as amended from time to time, as set forth in writing, and as delivered or made available to Executive (each, a “Policy”).

2. Compensation and Related Matters.

(a) Annual Base Salary. During the Term, Executive shall receive a base salary at a rate of $397,000 per annum, which shall be paid in accordance with the customary payroll practices of the Company and shall be pro-rated for partial years of employment. Such annual base salary shall be reviewed (and may be adjusted) from time to time by the Board of Directors of the Company or an authorized committee of the Board (in either case, the “Board,” and (such annual base salary, as it may be adjusted from time to time, the “Annual Base Salary”).

(b) Bonus. During the Term, Executive will be eligible to participate in an annual incentive program established by the Board. Executive’s annual incentive compensation under such incentive program (the “Annual Bonus”) shall be targeted at 40% of Executive’s Annual Base Salary (such target, as may be adjusted by the Board from time to time, the “Target Bonus”). The Annual Bonus payable under the incentive program shall be based on the achievement of performance goals to be determined by the Board. The payment of any Annual Bonus pursuant to the incentive program shall be subject to Executive’s continued employment with the Company through the date of payment, except as otherwise provided in Section 4(b).

3. Termination.

(a) Circumstances.

(i) Death. Executive’s employment hereunder shall terminate upon Executive’s death.

(ii) Disability. If Executive has incurred a Disability, as defined below, the Company may terminate Executive’s employment.

(iii) Termination for Cause. The Company may terminate Executive’s employment for Cause, as defined below.

(iv) Termination without Cause. The Company may terminate Executive’s employment without Cause.

(v) Resignation from the Company for Good Reason. Executive may resign Executive’s employment with the Company for Good Reason, as defined below.

(vi) Resignation from the Company Without Good Reason. Executive may resign Executive’s employment with the Company for any reason other than Good Reason or for no reason.

Company’s receipt of such Notice of Termination and is prior to the date specified in such Notice of Termination but the termination will still be considered a resignation by Executive. A Notice of Termination submitted by the Company may provide for a Date of Termination on the date Executive receives the Notice of Termination, or any date thereafter elected by the Company in its sole discretion. The failure by the Company to set forth in the Notice of Termination any fact or circumstance which contributes to a showing of Cause shall not waive any right of the Company hereunder or preclude the Company from asserting such fact or circumstance in enforcing the Company’s rights hereunder.

4. Severance Payments.

(i) an amount in cash equal to the product of (x) 1.0 times (y) the Annual Base Salary, payable in the form of salary continuation in regular installments over the 12-month period following the date of Executive’s Separation from Service (the “Severance Period”) in accordance with the Company’s normal payroll practices;

(iii) if Executive timely elects to receive continued medical, dental or vision coverage under one or more of the Company’s group healthcare plans pursuant to the Consolidated Omnibus Budget Reconciliation Act of 1985, as amended (“COBRA”), then the Company shall directly pay, or reimburse Executive for, the COBRA premiums for Executive and Executive’s covered dependents under such plans during the period commencing on Executive’s Separation from Service and ending upon the earliest of (X) the last day of the Severance Period, (Y) the date that Executive and/or Executive’s covered dependents become no longer eligible for COBRA or (Z) the date Executive becomes eligible to receive healthcare coverage from a subsequent employer (and Executive agrees to promptly notify the Company of such eligibility). Notwithstanding the foregoing, if the Company determines in its sole discretion that it cannot provide the foregoing benefit without potentially violating applicable law (including, without limitation, Section 2716 of the Public Health Service Act) or incurring an excise tax, the Company shall in lieu thereof provide to Executive a taxable monthly payment in an amount equal to the monthly COBRA premium that Executive would be required to pay to continue Executive’s and Executive’s covered dependents’ group health coverage in effect on the Date of Termination (which amount shall be based on the premium for the first month of COBRA coverage), which payments shall be made regardless of whether Executive elects COBRA continuation coverage and shall commence in the month following the month in which the Date of Termination occurs and shall end on the earlier of (X) the last day of the Severance Period, (Y) the date that Executive and/or Executive’s covered dependents become no longer eligible for COBRA or (Z) the date Executive becomes eligible to receive healthcare coverage from a subsequent employer (and Executive agrees to promptly notify the Company of such eligibility).

(i) without duplication, the payments and benefits described in Section 4(b);

(ii) an amount in cash equal to the product of (x) 1.0 times (y) the Target Bonus, payable in a lump sum within thirty (30) days following the later of Executive’s Separation from Service and the date of a Change in Control; and

5. Restrictive Covenants. Prior to the effectiveness of this Agreement, Executive has executed and delivered to the Company an Employee Non-Competition, Non-Solicitation, Confidentiality and Assignment Agreement (the “Proprietary Information Agreement”). Executive acknowledges and agrees that Executive continues to be bound **** by the existing terms of the Proprietary Information Agreement, and nothing in this Agreement affects or modifies the terms of the Proprietary Information Agreement. Executive acknowledges that the provisions of the Proprietary Information Agreement will survive the termination of Executive’s employment and the termination of the Term for the periods set forth in the Proprietary Information Agreement. ****

6. Assignment and Successors.

7. Certain Definitions.

(a) Cause. The Company shall have “Cause” to terminate Executive’s employment hereunder upon:

(ii) the Board’s determination that Executive refused in any material respect to carry out or comply with any lawful and reasonable directive of the Board;

(iii) Executive’s material breach of a material provision of this Agreement;

(iv) Executive’s conviction, plea of no contest, plea of nolo contendere, or imposition of unadjudicated probation for any felony or crime involving moral turpitude;

(vi) Executive’s commission of an act of fraud, embezzlement, misappropriation, willful misconduct, or breach of fiduciary duty against the Company or any of its affiliates;

(b) Change in Control. “Change in Control” shall have the meaning set forth in the version of the Seres Therapeutics, Inc. 2015 Incentive Award Plan in effect on the Effective Date.

(c) Code. “Code” shall mean the Internal Revenue Code of 1986, as amended, and the regulations and guidance promulgated thereunder.

(f) Good Reason. For the sole purpose of determining Executive’s right to severance payments and benefits as described above, Executive’s resignation will be for “Good Reason” if Executive resigns within ninety days after any of the following events, unless Executive consents to the applicable event: (i) a material decrease in Executive’s Annual Base Salary, (ii) a material decrease in Executive’s authority or areas of responsibility as are commensurate with Executive’s title or positions, including Executive ceasing to report directly to the chief executive officer of the Company’s ultimate parent company following a Change in Control (or of the Company if there is no such parent entity), (iii) the Company’s material breach of a material provision of this Agreement or another written agreement with Executive or (iv) the relocation of Executive’s primary office to a location more than 50 miles from the Boston metropolitan area. Notwithstanding the foregoing, no Good Reason will have occurred unless and until Executive has: (a) provided the Company, within 60 days of Executive’s knowledge of the occurrence of the facts and circumstances underlying the Good Reason event, written notice stating with reasonable specificity the applicable facts and circumstances underlying such finding of Good Reason; (b) provided the Company with an opportunity to cure the same within 30 days after the receipt of such notice; and (c) the Company shall have failed to cure such condition within such 30 day period.

8. Parachute Payments.

taxes on such reduced Total Payments and after taking into account the phase out of itemized deductions and personal exemptions attributable to such reduced Total Payments), is greater than or equal to (ii) the net amount of such Total Payments without such reduction (but after subtracting the net amount of federal, state and local income and employment taxes on such Total Payments and the amount of the Excise Tax to which Executive would be subject in respect of such unreduced Total Payments and after taking into account the phase out of itemized deductions and personal exemptions attributable to such unreduced Total Payments).

9.Miscellaneous Provisions.

(i) If to the Company, the Chief Financial Officer at its headquarters,

(ii) If to Executive, at the last address that the Company has in its personnel records for Executive, or

(iii) at any other address as any Party shall have specified by notice in writing to the other Party.

(e) Entire Agreement. The terms of this Agreement, and the Proprietary Information Agreement incorporated herein by reference as set forth in Section 5, are intended by the Parties to be the final expression of their agreement with respect to the subject matter hereof and supersede all prior understandings and agreements, whether written or oral, including the Prior Agreement. The Parties further intend that this Agreement shall constitute the complete and exclusive statement of their terms and that no extrinsic evidence whatsoever may be introduced in any judicial, administrative, or other legal proceeding to vary the terms of this Agreement.

(i) Arbitration. Any controversy, claim or dispute arising out of or relating to this Agreement, shall be settled solely and exclusively by a binding arbitration process administered by JAMS/Endispute in Boston, Massachusetts. Such arbitration shall be conducted in accordance with the then-existing JAMS/Endispute Rules of Practice and Procedure, with the following exceptions if in conflict: (i) one arbitrator who is a retired judge shall be chosen by JAMS/Endispute; (ii) each Party to the arbitration will pay one-half of the expenses and fees of the arbitrator, together with other expenses of the arbitration incurred or approved by the arbitrator; and (iii) arbitration may proceed in the absence of any Party if written notice (pursuant to the JAMS/Endispute rules and regulations) of the proceedings has been given to such Party. Each Party shall bear its own attorney’s fees and expenses; provided that the arbitrator may assess the prevailing Party’s fees and costs against the non-prevailing Party as part of the arbitrator’s award. The Parties agree to abide by all decisions and awards rendered in such proceedings. Such decisions and awards rendered by the arbitrator shall be final and conclusive. All such controversies, claims or disputes shall be settled in this manner in lieu of any action at law or equity; provided, however, that nothing in this subsection shall be construed as precluding the bringing of an action for injunctive relief or specific performance as provided in this Agreement or Proprietary Information Agreement. This dispute resolution process and any arbitration hereunder shall be confidential and neither any Party nor the neutral arbitrator shall disclose the existence, contents or results of such process without the prior written consent of all Parties, except where necessary or compelled in a court to enforce this arbitration provision or an award from such arbitration or otherwise in a legal proceeding. If JAMS/Endispute no longer exists or is otherwise unavailable, the Parties agree that the American Arbitration Association (“AAA”) shall administer the arbitration in accordance with its then-existing rules as modified by this subsection. In such event, all references herein to JAMS/Endispute shall mean AAA. Notwithstanding the foregoing, Executive and the Company each have the right to resolve any issue or dispute over intellectual property rights by court action instead of arbitration.

(l) Section 409A.

(ii) Separation from Service. Notwithstanding anything in this Agreement to the contrary, any compensation or benefits payable under this Agreement that is designated under this Agreement as payable upon Executive’s termination of employment shall be payable only upon Executive’s “separation from service” with the Company within the meaning of Section 409A (a “Separation from Service”) and, except as provided below, any such compensation or benefits described in Section 4 shall not be paid, or, in the case of installments, shall not commence payment, until the thirtieth (30th) day following Executive’s Separation from Service (the “First Payment Date”). Any installment payments that would have been made to Executive during the thirty (30) day period immediately following Executive’s Separation from Service but for the preceding sentence shall be paid to Executive on the First Payment Date and the remaining payments shall be made as provided in this Agreement.

reimbursement request promptly following the date the expense is incurred, (iii) the amount of expenses reimbursed in one year shall not affect the amount eligible for reimbursement in any subsequent year, other than medical expenses referred to in Section 105(b) of the Code, and (iv) Executive’s right to reimbursement under this Agreement will not be subject to liquidation or exchange for another benefit.

10. Executive Acknowledgement.

[Signature Page Follows]

IN WITNESS WHEREOF, the Parties have executed this Agreement on the date and year first above written.

SERES THERAPEUTICS, INC.
By:	/s/ Eric D. Shaff
	Name: Eric D. Shaff
	Title: President, CEO
/s/ Matthew R. Henn
Matthew R. Henn, Ph.D.

[Signature Page toEmployment Agreement]

EXHIBIT A

Separation Agreement and Release

This Separation Agreement and Release (“Agreement”) is made by and between Matthew R. Henn, Ph.D. (“Executive”) and Seres Therapeutics, Inc. (the “Company”) (collectively referred to as the “Parties” or individually referred to as a “Party”). Capitalized terms used but not defined in this Agreement shall have the meanings set forth in the Employment Agreement (as defined below).

WHEREAS, the Parties have previously entered into that certain Second Amended and Restated Employment Agreement, dated as of _____________, 2021 (the “Employment Agreement”); and

Severance Payments and Benefits; Salary and Benefits. The Company agrees to provide Executive with the severance payments and benefits described in Section 4(b) and/or Section 4(c) of the Employment Agreement, payable at the times set forth in, and subject to the terms and conditions of, the Employment Agreement. In addition, to the extent not already paid, and subject to the terms and conditions of the Employment Agreement, the Company shall pay or provide to Executive all other payments or benefits described in Section 3(c) of the Employment Agreement, subject to and in accordance with the terms thereof.
Release of Claims. Executive agrees that, other than with respect to the Retained Claims, the foregoing consideration represents settlement in full of all outstanding obligations owed to Executive by the Company, any of its direct or indirect subsidiaries and affiliates, and any of its or their respective current and former officers, directors, equity holders, managers, employees, agents, investors, attorneys, shareholders, administrators, affiliates, benefit plans, plan administrators, insurers, trustees, divisions, and subsidiaries and predecessor and successor corporations and assigns (collectively, the “Releasees”). Executive, on Executive’s own behalf and on behalf of any of Executive’s affiliated companies or entities and any of Executive’s or their respective heirs, family members, executors, agents, and assigns, other than with respect to

the Retained Claims, hereby and forever releases the Releasees from, and agrees not to sue concerning, or in any manner to institute, prosecute, or pursue, any claim, complaint, charge, duty, obligation, or cause of action relating to any matters of any kind, whether presently known or unknown, suspected or unsuspected, that Executive may possess against any of the Releasees arising from any omissions, acts, facts, or damages that have occurred up until and including the date Executive signs this Agreement, including, without limitation:

(b) any and all claims relating to, or arising from, Executive’s right to purchase, or actual purchase of any shares of stock or other equity interests of the Company or any of its affiliates, including, without limitation, any claims for fraud, misrepresentation, breach of fiduciary duty, breach of duty under applicable state law, and securities fraud under any state or federal law;

(d) any and all claims for violation of any federal, state, or municipal statute, including, but not limited to, Title VII of the Civil Rights Act of 1964; the Civil Rights Act of 1991; the Rehabilitation Act of 1973; the Americans with Disabilities Act of 1990; the Equal Pay Act; the Fair Labor Standard Act; the Fair Credit Reporting Act; the Age Discrimination in Employment Act of 1967; the Older Workers Benefit Protection Act; the Employee Retirement Income Security Act of 1974; the Worker Adjustment and Retraining Notification Act; the Family and Medical Leave Act; and the Sarbanes-Oxley Act of 2002;

(e) any and all claims for violation of the federal or any state constitution;

(f) any and all claims arising out of any other laws and regulations relating to employment or employment discrimination;

(h) any and all claims arising out of the wage and hour and wage payments laws and regulations of the state or states in which Executive has provided service to the Company or any of its affiliates (including without limitation the Massachusetts Payment of Wages Law); and

A-2

(i) any and all claims for attorneys’ fees and costs.

Executive agrees that the release set forth in this section shall be and remain in effect in all respects as a complete general release as to the matters released. This release does not release claims that cannot be released as a matter of law, including, but not limited to, Executive’s right to report possible violations of federal law or regulation to any governmental agency or entity in accordance with the provisions of and rules promulgated under Section 21F of the Securities Exchange Act of 1934 or Section 806 of the Sarbanes-Oxley Act of 2002, or any other whistleblower protection provisions of state or federal law or regulation (including Executive’s right to receive an award for information provided to any such government agencies), Executive’s right to file a charge with or participate in a charge by the Equal Employment Opportunity Commission, or any other local, state, or federal administrative body or government agency that is authorized to enforce or administer laws related to employment, against the Company (with the understanding that Executive’s release of claims herein bars Executive from recovering monetary or other individual relief from the Company or any Releasee in connection with any charge, investigation or proceeding, or any related complaint or lawsuit, filed by Executive or by anyone else on Executive’s behalf before the federal Equal Employment Opportunity Commission or a comparable state or local agency), claims for unemployment compensation or any state disability insurance benefits pursuant to the terms of applicable state law, claims to continued participation in certain of the Company’s group benefit plans pursuant to the terms and conditions of COBRA, claims to any benefit entitlements vested as the date of separation of Executive’s employment, pursuant to written terms of any employee benefit plan of the Company or its affiliates and Executive’s right under applicable law, and any Retained Claims. This release further does not release claims for breach of Section 3(c), Section 4(b) or Section 4(c) of the Employment Agreement.

Acknowledgment of Waiver of Claims under ADEA. Executive understands and acknowledges that Executive is waiving and releasing any rights Executive may have under the Age Discrimination in Employment Act of 1967 (“ADEA”), and that this waiver and release is knowing and voluntary. Executive understands and agrees that this waiver and release does not apply to any rights or claims that may arise under the ADEA after the date Executive signs this Agreement. Executive understands and acknowledges that the consideration given for this waiver and release is in addition to anything of value to which Executive was already entitled. Executive further understands and acknowledges that Executive has been advised by this writing that: (a) Executive should consult with an attorney prior to executing this Agreement; (b) Executive has 21 days within which to consider this Agreement, and the Parties expressly agree that such time period to review this Agreement shall not be extended upon any material or immaterial changes to this Agreement; (c) Executive has seven business days following Executive’s execution of this Agreement to revoke this Agreement pursuant to written notice to the General Counsel of the Company; (d) this Agreement shall not be effective until after the revocation period has expired; and (e) nothing in this Agreement prevents or precludes Executive from challenging or seeking a determination in good faith of the validity of this waiver under the ADEA, nor does it impose any condition precedent, penalties, or costs for doing so, unless specifically authorized by federal law. In the event Executive signs this Agreement and returns it to the Company in less than the 21 day period identified above, Executive hereby acknowledges that Executive has freely and voluntarily chosen to waive the time period allotted for considering this Agreement.

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Post-Termination Obligations. Executive reaffirms Executive’s continuing obligations under the Proprietary Information Agreement between Executive and the Company dated as of [_________], and, without limiting the foregoing, Executive remakes the non-competition covenants set forth in the Proprietary Information Agreement as if set forth herein. In addition, Executive agrees to refrain from Disparaging (as defined below) the Company and its affiliates, including their respective services, technologies, practices, directors and officers. The Company agrees to instruct its officers and directors to refrain from Disparaging Executive. Nothing in this Section shall preclude any Party from making truthful statements that are reasonably necessary to comply with applicable law, regulation or legal process, or to defend or enforce a Party’s rights under this Agreement or the Employment Agreement. For purposes of this Agreement, “Disparaging” means making remarks, comments or statements, whether written or oral, that impugn the character, integrity, reputation or abilities of the individual or entity being disparaged.
Severability. In the event that any provision or any portion of any provision hereof or any surviving agreement made a part hereof becomes or is declared by a court of competent jurisdiction or arbitrator to be illegal, unenforceable, or void, this Agreement shall continue in full force and effect without said provision or portion of provision.

6 No Oral Modification. This Agreement may only be amended in a writing signed by Executive and a duly authorized officer of the Company.

Governing Law; Dispute Resolution. This Agreement shall be subject to the provisions of Sections 9(a), 9(c) and 9(i) of the Employment Agreement.

Effective Date. Executive has seven business days after Executive signs this Agreement to revoke it and this Agreement will become effective upon the expiration of such seven business day period, so long as it has been signed by the Parties and has not been revoked by Executive before that date.

Trade Secrets; Whistleblower Protections. In accordance with 18 U.S.C. §1833, notwithstanding anything to the contrary in this Agreement, the Employment Agreement, the Proprietary Information Agreement or any other agreement between Executive and the Company or any of its subsidiaries in effect as of the date Executive receives this Agreement (together, the “Subject Documents”): (a) Executive will not be in breach of the Subject Documents, 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 Executive files a lawsuit for retaliation by the Company for reporting a suspected violation of law, Executive may disclose the trade secret to Executive’s attorney, and may use the trade secret information in the court proceeding, if Executive files any document containing the trade secret under seal, and does not disclose the trade secret, except pursuant to court order. Furthermore, the Parties agree

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that nothing in the Subject Documents prohibits Executive from reporting possible violations of federal law or regulation to any governmental agency or entity in accordance with the provisions of and rules promulgated under Section 21F of the Securities Exchange Act of 1934 or Section 806 of the Sarbanes-Oxley Act of 2002, or any other whistleblower protection provisions of state or federal law or regulation or releases or restrains Executive’s right to receive an award for information provided to any such government agencies.

Voluntary Execution of Agreement. Executive understands and agrees that Executive executed this Agreement voluntarily, without any duress or undue influence on the part or behalf of the Company or any third party, with the full intent of releasing all of Executive’s claims against the Company and any of the other Releasees. Executive acknowledges that: (a) Executive has read this Agreement; (b) Executive has not relied upon any representations or statements made by the Company that are not specifically set forth in this Agreement; (c) Executive has been represented in the preparation, negotiation, and execution of this Agreement by legal counsel of Executive’s own choice or has elected not to retain legal counsel; (d) Executive understands the terms and consequences of this Agreement and of the releases it contains; and (e) Executive is fully aware of the legal and binding effect of this Agreement.

[Signature Page Follows]

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IN WITNESS WHEREOF, the Parties have executed this Agreement on the respective dates set forth below.

Dated:
	Matthew R. Henn, Ph.D.
	SERES THERAPEUTICS, INC.
Dated:	By:
		Name:<br> <br>Title:

EX-10.3

Exhibit 10.3

Seres Therapeutics, Inc.

101 Cambridge Park Drive

Cambridge, Massachusetts 02140

March 2, 2026

Richard N. Kender

By Email Delivery

Dear Rich,

This letter confirms the terms under which you will be employed as the Executive Chair and Interim Chief Executive Officer of Seres Therapeutics, Inc. (the “Company”), in addition to your continued service on the Company’s Board of Directors (the “Board”). Capitalized terms used but not defined in this letter have the meaning given to them on the attached Exhibit A.

Effective Date; Duties; Expenses. Your term of employment as Executive Chair and Interim Chief Executive Officer will commence on March 2, 2026 or another date mutually agreed between you and the Board (the “Effective Date”) and continue until terminated in accordance with Section 4 (the “Term”). During the Term, you will have the responsibilities, duties and authority as are customarily associated with such positions or agreed between you and the Company. You will report to the Board and will be permitted to work remotely; however, you agree to be present in the Company’s offices in-person and to dedicate sufficient time to your duties hereunder as is reasonably necessary for their proper performance. During the Term, the Company will reimburse you for all reasonable travel and other business expenses incurred by you in the performance of your duties to the Company in accordance with the Company’s expense reimbursement policies. To the extent the Company determines that any travel expense reimbursements are taxable income to you, the Company will provide you with an additional payment so that after-tax you will be reimbursed for the full amount of the reimbursable travel expenses incurred. You agree to submit requests for such reimbursements reasonably promptly following the date you incur the applicable expenses and in accordance with the Company’s expense reimbursement policies. The Company will provide such reimbursements reasonably promptly following the receipt of such request and reasonable supporting documentation in accordance with the Company’s expense reimbursement policies. In addition, any reimbursement of taxes hereunder will be paid in all events not later than the year following the year in which the applicable taxes were paid.
BaseSalary. Your base salary for this position will be at the rate of $520,000 per year, payable in installments in accordance with the Company’s payroll practices and procedures as in effect from time to time and prorated for any partial period of employment.
Annual Bonus. During the Term, you will be eligible to receive a discretionary annual performance bonus, which in recognition of your contributions to the Company during 2026 prior to the Effective Date, will not be prorated for the portion of 2026 elapsed prior to the Effective Date. Your target annual performance bonus amount will be 55% of your annual base salary, with the opportunity for additional, discretionary performance-based upside linked to timely achievement of meaningful financing, transactional or collaboration results for the Company. The timing and amount of any annual bonus payable to you will be determined by the Board in its discretion, and payment of any such bonus will be subject to your continued employment with the Company through the date of payment.
At-Will Employment; Termination. It is understood that your employment will at all times be “at-will.” You are not being offered employment for a definite period of time, and either you or the Company may terminate the employment relationship at any time and for any reason or no reason by providing written notice of such termination to the other. If your employment terminates for any reason, you will not be entitled to any payments, benefits, damages, award or compensation other than as required by applicable law.
Director Compensation. During the Term, you will not receive additional compensation from the Company for service on the Board or any of its committees. As of the Effective Date, you will cease to be eligible for compensation as a non-employee director under the Company’s Non-Employee Director Compensation Program (the “Program”). However, and notwithstanding the terms of any Company equity awards held by you, your service during the Term will be deemed to satisfy any continued service requirements that apply under such equity awards, with the effect that such equity awards will continue to vest and/or remain outstanding and, as applicable, exercisable during the Term and thereafter during any period that you otherwise continue to satisfy the applicable service conditions in accordance with and subject to the terms of such awards. Upon termination of your employment, you will again become eligible for compensation under the Program, subject to its terms.
Equity Award. Subject to approval by the Board, the Company will grant you options (the “Options”) under the Company’s 2025 Incentive Award Plan (the “Plan”) to purchase 200,000 shares of the Company’s common stock (subject to adjustment for corporate events as set forth in the Plan) at an exercise price per share equal to the per share fair market value of the Company’s common stock on the date of grant, as determined in accordance with the Plan, provided that 25% of the Options (the “Contingent Option”) shall be conditioned on stockholder approval no later than the Company’s annual stockholder meeting for 2026 of an amendment to the Plan increasing the number of shares of the Company’s common stock available for issuance under the Plan, and if such stockholder approval is not obtained, the Contingent Option will be forfeited without consideration. The Options will vest in equal monthly installments over three years commencing on the Effective Date, subject to your continuous service through the applicable vesting date. In all respects, the Options will be governed by and subject to the terms of the Plan and a separate stock option agreement to be entered into between you and the Company. If the Company terminates your employment without Cause or you resign for Good Reason, in either case, within 60 days prior to or 12 months following the date of a Change in Control, any unvested portion of the Options will immediately become 100% vested (and if the date of your termination precedes the Change in Control, the unvested portion of the Options will remain outstanding and eligible to vest in accordance with this sentence if a Change in Control occurs within 60 days after the date of your termination, provided that in no event will the Options remain outstanding beyond the final expiration date set forth in the stock option agreement governing the Options). In addition, in the event of your death, the unvested portion of any outstanding Company options you hold will become fully vested.

Signing Bonus. The Company will pay you a one-time signing bonus in the amount of $250,000 (the “Signing Bonus”), payable with your first Company paycheck. If you voluntarily terminate your employment with the Company without Good Reason or the Company terminates your employment for Cause, in each case, before December 31, 2026, you agree to repay the Company within thirty days after your final day of employment the amount of the Signing Bonus net of taxes withheld by the Company upon its payment to you. You further agree that the Company will be entitled (but not required) to deduct any such repayment amount from the after-tax amount of any payments owed by the Company to you, subject to applicable law.
Proprietary Information Agreement; Company Policies. As a condition to your employment, you are required to execute and deliver to the Company the enclosed Employee Non-Competition, Non-Solicitation, Confidentiality and Assignment Agreement (the “Proprietary Information Agreement”) no later than the Effective Date. You acknowledge that the provisions of the Proprietary Information Agreement will survive the termination of your employment for the periods set forth in the Proprietary Information Agreement. You may also be required to execute additional documents at the Company’s request, including documents relating to the Company’s internal policies, compliance with applicable tax laws, or any other applicable law.
Taxes. All forms of compensation referred to in this offer letter are subject to reduction to reflect applicable withholding and payroll taxes and other deductions required by law.
Assignment. Neither you nor the Company may make any assignment of this letter or any interest in it, by operation of law or otherwise, without the prior written consent of the other; provided, however, that the Company may assign its rights and obligations under this letter (including the Proprietary Information Agreement) without your consent to any affiliate or to any person or entity with whom the Company shall hereafter effect a reorganization, consolidate with, or merge into or to whom it transfers all or substantially all of its properties or assets. This letter shall inure to the benefit of and be binding upon you and the Company, and each of your and its respective successors, executors, administrators, heirs and permitted assigns.
Miscellaneous. This letter may not be modified or amended, and no breach shall be deemed to be waived, except by a written agreement signed by you and an authorized officer of the Company. The headings and captions in this letter are for convenience only and in no way define or describe the scope or content of any provision of this letter. This letter may be executed in counterparts, each of which shall be an original and all of which together shall constitute one and the same instrument.
OtherTerms. In making this offer, the Company understands, and in accepting it you represent, that you are not under any obligation to any person, firm, or corporation that would prevent, limit, or impair in any way the performance by you of your duties as an employee of the Company.

[Signature Page Follows]

Please indicate your agreement to the terms of this letter by returning a signed copy to the undersigned within seven days of the date hereof, after which time the Company’s offer to enter into this letter will automatically expire.

Very truly yours,
SERES THERAPEUTICS, INC.
By:	/s/ Stephen Berenson
Name: Stephen Berenson
Title: Chairman of the Board of Directors

Accepted and Agreed:

/s/ Richard N. Kender
Richard N. Kender

[Signature Page toEmployment Letter Agreement]

Exhibit A

When used in the letter to which this Exhibit A is attached, the following capitalized terms have the meanings provided below.

“Cause” means (i) your refusal to (A) substantially perform your duties with the Company or (B) comply with, in any material respect, any of the Company’s policies that are applicable to you; (ii) the Board’s determination that you refused in any material respect to carry out or comply with any lawful and reasonable directive of the Board; (iii) your material breach of a material provision of a written agreement with the Company; (iv) your conviction, plea of no contest, plea of nolo contendere, or imposition of unadjudicated probation for any felony or crime involving moral turpitude; (v) your unlawful use (including being under the influence) or possession of illegal drugs on the Company’s (or any of its affiliate’s) premises or while performing your duties and responsibilities for the Company; or (vi) your commission of an act of fraud, embezzlement, misappropriation, willful misconduct, or breach of fiduciary duty against the Company or any of its affiliates; provided, however, that your termination will not be considered for Cause unless and until (a) the Company has provided you, within 60 days of the Company’s knowledge of the occurrence of the facts and circumstances underlying the Cause event, written notice stating with reasonable specificity the applicable facts and circumstances underlying such finding of Cause and (b) in the case of alleged Cause under clause (i), (ii) or (iii) of the foregoing definition and to the extent the applicable condition or event is reasonably capable of being cured, you have failed to cure such condition or event within 30 days after the receipt of such notice.
“Change inControl” has the meaning set forth in the version of the Plan in effect on the Effective Date.
Your resignation will be for “Good Reason” if you resign within 90 days after any of the following events, unless you consent to the applicable event: (i) a material decrease in your annual base salary, (ii) a material decrease in your authority or areas of responsibility as are commensurate with your title or positions, including your ceasing to report directly to the Board, or (iii) the Company’s material breach of a material provision of a written agreement with you, provided that the Company’s appointment of a Chief Executive Officer shall not constitute Good Reason. Notwithstanding the foregoing, no Good Reason will have occurred unless and until you have: (a) provided the Company, within 60 days of your knowledge of the occurrence of the facts and circumstances underlying the Good Reason event, written notice stating with reasonable specificity the applicable facts and circumstances underlying such finding of Good Reason; (b) provided the Company with an opportunity to cure the same within 30 days after the receipt of such notice; and (c) the Company shall have failed to cure such condition within such 30 day period.

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