EX-10.5



 Exhibit 10.5 

FORM OF 

INDEMNIFICATION AGREEMENT 

THIS INDEMNIFICATION AGREEMENT (this “Agreement”) is made and entered into as of
[            ] [    ], 20[    ], by and between Seres Therapeutics, Inc. (the “Company”) and
[                    ] (“Indemnitee”). 

RECITALS 
 WHEREAS,
the Company values Indemnitee’s service to the Company as a director or officer and desires that Indemnitee continue to serve the Company in such capacity; 

WHEREAS, Indemnitee does not regard the protection available under the organizational documents of the Company and any insurance
policies maintained by the Company as adequate in the present circumstances, and Indemnitee may not be willing to continue to serve in his or her capacity as a director or officer of the Company without the additional protections set forth in this
Agreement; 
 WHEREAS, the Board of Directors of the Company (the “Board”) has determined that, on the basis
of the foregoing, it is reasonable, prudent and necessary for the Company to obligate itself contractually to indemnify, and to advance expenses on behalf of, Indemnitee to the fullest extent permitted by applicable law so that Indemnitee will serve
or continue to serve the Company free from undue concern that he or she will not be so indemnified; 
 WHEREAS, this Agreement is a
supplement to and in furtherance of the organizational documents of the Company and any resolutions adopted pursuant thereto, and shall not be deemed a substitute therefor, nor to diminish or abrogate any rights of Indemnitee thereunder; and 

WHEREAS, Indemnitee may have certain rights to indemnification and/or insurance provided by an investment or venture capital fund with
which Indemnitee is or may become affiliated (the “Associated Fund”) which Indemnitee and the Associated Fund intend to be secondary to the primary obligation of the Company to indemnify Indemnitee as provided herein, with
the Company’s acknowledgement and agreement to the foregoing being a material condition to Indemnitee’s willingness to serve on the Board. 

NOW, THEREFORE, in consideration of the mutual promises and agreements herein contained, and intending to be legally bound, the parties
hereto agree as follows: 
 AGREEMENT 

1. INDEMNIFICATION OF INDEMNITEE AND ASSOCIATED FUND. The Company hereby agrees to hold harmless and indemnify Indemnitee to the fullest extent
permitted by applicable law, as such may be amended from time to time. In furtherance of the foregoing indemnification, and without limiting the generality thereof: 

(a) Indemnitee shall be entitled to the rights of indemnification provided in this Section 1(a) if, by reason of his or her
Corporate Status (as defined in Section 13(c)), the 







 
Indemnitee is, or is threatened to be made, a party to or participant in any Proceeding (as defined in Section 13(j)) other than a Proceeding by or in the right of the Company.
Pursuant to this Section 1(a), Indemnitee shall be indemnified against all Expenses (as defined in Section 13(g)), judgments, penalties, fines and amounts paid in settlement actually and reasonably incurred by him or her, or
on his or her behalf, in connection with such Proceeding or any claim, issue or matter therein, if the Indemnitee acted in good faith and in a manner the Indemnitee reasonably believed to be in or not opposed to the best interests of the Company,
and with respect to any criminal Proceeding, had no reasonable cause to believe the Indemnitee’s conduct was unlawful. 
 (b)
Indemnitee shall be entitled to the rights of indemnification provided in this Section 1(b) if, by reason of his or her Corporate Status, the Indemnitee is, or is threatened to be made, a party to or participant in any Proceeding
brought by or in the right of the Company. Pursuant to this Section 1(b), Indemnitee shall be indemnified against all Expenses actually and reasonably incurred by the Indemnitee, or on the Indemnitee’s behalf, in connection with
such Proceeding if the Indemnitee acted in good faith and in a manner the Indemnitee reasonably believed to be in or not opposed to the best interests of the Company; provided, however, that if applicable law so provides, no
indemnification against such Expenses shall be made in respect of any claim, issue or matter in such Proceeding as to which Indemnitee shall have been adjudged to be liable to the Company unless and to the extent that a court of competent
jurisdiction shall determine that such indemnification may be made. 
 (c) Notwithstanding any other provision of this Agreement, to
the extent that Indemnitee is, by reason of his or her Corporate Status, a party to and is successful, on the merits or otherwise, in any Proceeding, he or she shall be indemnified to the maximum extent permitted by law, as such may be amended from
time to time, against all Expenses actually and reasonably incurred by him or her, or on his or her behalf, in connection therewith. If Indemnitee is not wholly successful in such Proceeding but is successful, on the merits or otherwise, as to one
or more but less than all claims, issues or matters in such Proceeding, the Company shall indemnify Indemnitee against all Expenses actually and reasonably incurred by him or her, or on his or her behalf, in connection with each successfully
resolved claim, issue or matter. For purposes of this Section 1(c) and without limitation, the termination of any claim, issue or matter in such a Proceeding by dismissal, with or without prejudice, shall be deemed to be a successful
result as to such claim, issue or matter. 
 (d) If the Associated Fund is, or is threatened to be made, a party to or a participant
in any Proceeding relating to or arising by reason of the Associated Fund’s position as a stockholder of, or lender to, the Company, or the Associated Fund’s appointment of or affiliation with Indemnitee or any other director, including
without limitation any alleged misappropriation of a Company asset or corporate opportunity, any claim of misappropriation or infringement of intellectual property relating to the Company, any alleged false or misleading statement or omission made
by the Company (or on its behalf) or its employees or agents, or any allegation of inappropriate control or influence over the Company or its Board members, officers, equity holders or debt holders, then the Associated Fund will be entitled to
indemnification hereunder for Expenses to the same extent as Indemnitee, and the terms of this Agreement as they relate to procedures for indemnification of Indemnitee and advancement of Expenses shall apply to any such indemnification of the
Associated Fund. The rights provided to the Associated Fund under this Section 1(d) shall: (i) be suspended during any period during which the Associated Fund 

  
 2 








 
does not have a representative on the Board; and (ii) terminate on an initial public offering of the Company’s Common Stock under the Securities Act of 1933, as amended (an
“IPO”); provided, however, that in the event of any such suspension or termination, the Associated Fund’s rights to indemnification will not be suspended or terminated with respect to any Proceeding based
in whole or in part on facts and circumstances occurring at any time prior to such suspension or termination regardless of whether the Proceeding arises before or after such suspension or termination. The Company and Indemnitee agree that the
Associated Fund is an express third party beneficiary of the terms of this Section 1(d). 
 2. ADDITIONAL INDEMNITY. In addition to, and
without regard to any limitations on, the indemnification provided for in Section 1 of this Agreement, the Company shall and hereby does indemnify and hold harmless Indemnitee against all Expenses, judgments, penalties, fines and amounts
paid in settlement actually and reasonably incurred by him or her, or on his or her behalf if, by reason of his or her Corporate Status, he or she is, or is threatened to be made, a party to or participant in any Proceeding (including a Proceeding
by or in the right of the Company), including, without limitation, all liability arising out of the negligence or active or passive wrongdoing of Indemnitee. The only limitation that shall exist upon the Company’s obligations pursuant to this
Agreement shall be that the Company shall not be obligated to make any payment to Indemnitee that is finally determined (under the procedures, and subject to the presumptions, set forth in Sections 6 and 7 hereof) to be unlawful.

 3. CONTRIBUTION. 
 (a) Whether
or not the indemnification provided in Sections 1 and 2 hereof is available, in respect of any Proceeding in which the Company is jointly liable with Indemnitee (or would be if joined in such Proceeding), the Company shall pay, in
the first instance, the entire amount of any judgment or settlement of such Proceeding without requiring Indemnitee to contribute to such payment and the Company hereby waives and relinquishes any right of contribution it may have against
Indemnitee. The Company shall not enter into any settlement of any Proceeding in which the Company is jointly liable with Indemnitee (or would be if joined in such Proceeding) unless such settlement provides for a full and final release of all
claims asserted against Indemnitee. 
 (b) Without diminishing or impairing the obligations of the Company set forth in
Section 3(a), if, for any reason, Indemnitee shall elect or be required to pay all or any portion of any judgment or settlement in any Proceeding in which the Company is jointly liable with Indemnitee (or would be if joined in such
Proceeding), the Company shall contribute to the amount of Expenses, judgments, fines and amounts paid in settlement actually and reasonably incurred and paid or payable by Indemnitee in proportion to the relative benefits received by the Company
and all officers, directors or employees of the Company, other than Indemnitee, who are jointly liable with Indemnitee (or would be if joined in such Proceeding), on the one hand, and Indemnitee, on the other hand, from the transaction from which
such Proceeding arose; provided, however, that the proportion determined on the basis of relative benefit may, to the extent necessary to conform to law, be further adjusted by reference to the relative fault of the Company and all
officers, directors or employees of the Company other than Indemnitee who are jointly liable with Indemnitee (or would be if joined in such Proceeding), on the one hand, and Indemnitee, on the other hand, in connection with the events that resulted
in such expenses, 

  
 3 








 
judgments, fines or settlement amounts, as well as any other equitable considerations which the Law may require to be considered. The relative fault of the Company and all officers, directors or
employees of the Company, other than Indemnitee, who are jointly liable with Indemnitee (or would be if joined in such Proceeding), on the one hand, and Indemnitee, on the other hand, shall be determined by reference to, among other things, the
degree to which their actions were motivated by intent to gain personal profit or advantage, the degree to which their liability is primary or secondary and the degree to which their conduct is active or passive. 

(c) The Company hereby agrees to fully indemnify and hold Indemnitee harmless from any claims of contribution which may be brought by
officers, directors or employees of the Company, other than Indemnitee, who may be jointly liable with Indemnitee. 
 (d) To the
fullest extent permissible under applicable law, if the indemnification provided for in this Agreement is unavailable to Indemnitee for any reason whatsoever, the Company, in lieu of indemnifying Indemnitee, shall contribute to the amount incurred
by Indemnitee, whether for judgments, fines, penalties, excise taxes, amounts paid or to be paid in settlement and/or for Expenses, in connection with any claim relating to an indemnifiable event under this Agreement, in such proportion as is deemed
fair and reasonable in light of all of the circumstances of such Proceeding in order to reflect: (i) the relative benefits received by the Company and Indemnitee as a result of the event(s) and/or transaction(s) giving cause to such Proceeding;
and/or (ii) the relative fault of the Company (and its directors, officers, employees and agents) and Indemnitee in connection with such event(s) and/or transaction(s). 

4. INDEMNIFICATION FOR EXPENSES OF A WITNESS. Notwithstanding any other provision of this Agreement, to the extent that Indemnitee is, by reason of his
or her Corporate Status, a witness, or is made (or asked to) respond to discovery requests, in any Proceeding to which Indemnitee is not a party, he or she shall be indemnified against all Expenses actually and reasonably incurred by him or her, or
on his or her behalf, in connection therewith. 
 5. ADVANCEMENT OF EXPENSES. Notwithstanding any other provision of this Agreement, the Company
shall advance all Expenses incurred by or on behalf of Indemnitee in connection with any Proceeding by reason of Indemnitee’s Corporate Status within thirty (30) days after the receipt by the Company of a statement or statements from
Indemnitee requesting such advance or advances from time to time, whether prior to or after final disposition of such Proceeding. Such statement or statements shall reasonably evidence the Expenses incurred by Indemnitee and shall include or be
preceded or accompanied by a written undertaking by or on behalf of Indemnitee to repay any Expenses advanced if it shall ultimately be determined that Indemnitee is not entitled to be indemnified against such Expenses. Any advances and undertakings
to repay pursuant to this Section 5 shall be unsecured and interest free. 
 6. PROCEDURES AND PRESUMPTIONS FOR DETERMINING ENTITLEMENT TO
INDEMNIFICATION. It is the intent of this Agreement to secure for Indemnitee rights of indemnification that are as favorable as may be permitted under applicable law. Accordingly, 

  
 4 








 
the parties agree that the following procedures and presumptions shall apply in the event of any question as to whether Indemnitee is entitled to indemnification under this Agreement: 

(a) To obtain indemnification under this Agreement, Indemnitee shall submit to the Company a written request, including therein or
therewith such documentation and information as is reasonably available to Indemnitee and is reasonably necessary to determine whether and to what extent Indemnitee is entitled to indemnification. The Secretary of the Company shall, promptly upon
receipt of such a request for indemnification, advise the Board in writing that Indemnitee has requested indemnification. Notwithstanding the foregoing, any failure of Indemnitee to provide such a request to the Company, or to provide such a request
in a timely fashion, shall not relieve the Company of any liability that it may have to Indemnitee unless, and to the extent that, such failure actually and materially prejudices the interests of the Company. 

(b) Upon written request by Indemnitee for indemnification pursuant to the first sentence of Section 6(a) hereof, a
determination with respect to Indemnitee’s entitlement thereto shall be made in the specific case by one of the following four methods, which shall be at the election of the Board: (i) by a majority vote of the Disinterested Directors (as
defined in Section 13(d)), even though less than a quorum; (ii) by a committee of those Disinterested Directors designated by a majority vote of the Disinterested Directors, even though less than a quorum; (iii) if there are no
Disinterested Directors or if the Disinterested Directors so direct, by Independent Counsel (as defined in Section 13(h)) in a written opinion to the Board, a copy of which shall be delivered to the Indemnitee, or (iv) if so
directed by the Board, by the stockholders of the Company; provided, however, that, notwithstanding the foregoing, any determination with respect to Indemnitee’s entitlement to indemnification hereunder that is made at any time
following the consummation of a Change in Control (as defined in Section 13(b)) that occurs at any time when the Company has a class of securities registered under the Exchange Act (as defined in Section 13(f)) or following
the consummation of an IPO shall be made solely by Independent Counsel in a written opinion to the Board, a copy of which shall be delivered to the Indemnitee. 

(c) If the determination of entitlement to indemnification is to be made by Independent Counsel pursuant to Section 6(b) hereof,
the Independent Counsel shall be selected as provided in this Section 6(c). The Independent Counsel shall be selected by the Board. Indemnitee may, within 10 days after such written notice of selection shall have been given, deliver to the
Company a written objection to such selection; provided, however, that such objection may be asserted only on the ground that the Independent Counsel so selected does not meet the requirements of “Independent Counsel” as
defined in Section 13(h) of this Agreement, and the objection shall set forth with particularity the factual basis of such assertion. Absent a proper and timely objection, the person so selected shall act as Independent Counsel. If a
written objection is made and substantiated, the Independent Counsel selected may not serve as Independent Counsel unless and until such objection is withdrawn or a court has determined that such objection is without merit. If, within 20 days
after submission by Indemnitee of a written request for indemnification pursuant to Section 6(a) hereof, no Independent Counsel shall have been selected and not objected to, either the Company or Indemnitee may petition a court of competent
jurisdiction for resolution of any objection which shall have been made by the Indemnitee to the Company’s selection of Independent Counsel and/or for the appointment as Independent Counsel of a person selected by the court or by such other
person as the court shall designate, and the person with respect to whom all objections are so resolved or the person so appointed shall act as Independent Counsel under Section 6(b) hereof. The Company shall pay any and all reasonable fees and
expenses of Independent Counsel incurred by such Independent 

  
 5 








 
Counsel in connection with acting pursuant to Section 6(b) hereof, and the Company shall pay all reasonable fees and expenses incident to the procedures of this Section 6(c), regardless
of the manner in which such Independent Counsel was selected or appointed. 
 (d) In making a determination with respect to
entitlement to indemnification hereunder, the person or persons or entity making such determination shall presume that Indemnitee is entitled to indemnification under this Agreement. Anyone seeking to overcome this presumption shall have the burden
of proof and the burden of persuasion by clear and convincing evidence. Neither the failure of the Company (including by its directors or independent legal counsel) to have made a determination prior to the commencement of any action pursuant to
this Agreement that indemnification is proper in the circumstances because Indemnitee has met the applicable standard of conduct, nor an actual determination by the Company (including by its directors or independent legal counsel) that Indemnitee
has not met such applicable standard of conduct, shall be a defense to the action or create a presumption that Indemnitee has not met the applicable standard of conduct. 

(e) Indemnitee shall be deemed to have acted in good faith if Indemnitee’s action is based on the records or books of account of
the Enterprise (as defined in Section 13(e)), including financial statements, or on information supplied to Indemnitee by the officers of the Enterprise in the course of their duties, or on the advice of legal counsel for the Enterprise
or on information or records given or reports made to the Enterprise by an independent certified public accountant or by an appraiser or other expert selected with reasonable care by the Enterprise. In addition, the knowledge and/or actions, or
failure to act, of any director, officer, agent or employee of the Enterprise shall not be imputed to Indemnitee for purposes of determining the right to indemnification under this Agreement. Whether or not the foregoing provisions of this
Section 6(e) are satisfied, it shall in any event be presumed that Indemnitee has at all times acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the Company. Anyone seeking
to overcome this presumption shall have the burden of proof and the burden of persuasion by clear and convincing evidence. 
 (f) If
the person, persons or entity empowered or selected under this Section 6 to determine whether Indemnitee is entitled to indemnification shall not have made a determination within sixty (60) days after receipt by the Company of the
request therefor, the requisite determination of entitlement to indemnification shall be deemed to have been made and Indemnitee shall be entitled to such indemnification absent: (i) a misstatement by Indemnitee of a material fact, or an
omission of a material fact necessary to make Indemnitee’s statement not materially misleading, in connection with the request for indemnification; or (ii) a prohibition of such indemnification under applicable law; provided,
however, that such 60-day period may be extended for a reasonable time, not to exceed an additional thirty (30) days, if the person, persons or entity making such determination with respect to
entitlement to indemnification in good faith requires such additional time to obtain or evaluate documentation and/or information relating thereto; and provided, further, that the foregoing provisions of this Section 6(f)
shall not apply if the determination of entitlement to indemnification is to be made by the stockholders pursuant to Section 6(b) of this Agreement and if (A) within fifteen (15) days after receipt by the Company of the request
for such determination, the Board or the Disinterested Directors, if appropriate, resolve to submit such determination to the stockholders for their consideration at an annual meeting thereof to be held within seventy-five (75) days after such
receipt and such 

  
 6 








 
determination is made thereat or (B) a special meeting of stockholders is called within fifteen (15) days after such receipt for the purpose of making such determination, such meeting
is held for such purpose within sixty (60) days after having been so called and such determination is made thereat. 
 (g)
Indemnitee shall cooperate with the person, persons or entity making such determination with respect to Indemnitee’s entitlement to indemnification, including providing to such person, persons or entity upon reasonable advance request any
documentation or information which is not privileged or otherwise protected from disclosure and which is reasonably available to Indemnitee and reasonably necessary to such determination. Any Independent Counsel, member of the Board or stockholder
of the Company shall act reasonably and in good faith in making a determination regarding the Indemnitee’s entitlement to indemnification under this Agreement. Any costs or expenses (including attorneys’ fees and disbursements) incurred by
Indemnitee in so cooperating with the person, persons or entity making such determination shall be borne by the Company (irrespective of the determination as to Indemnitee’s entitlement to indemnification) and the Company hereby indemnifies and
agrees to hold Indemnitee harmless therefrom. 
 (h) The Company acknowledges that a settlement or other disposition short of final
judgment may be successful if it permits a party to avoid expense, delay, distraction, disruption and uncertainty. In the event that any Proceeding to which Indemnitee is a party is resolved in any manner other than by adverse judgment against
Indemnitee (including, without limitation, settlement of such Proceeding with or without payment of money or other consideration) it shall be presumed that Indemnitee has been successful on the merits or otherwise in such Proceeding. Anyone seeking
to overcome this presumption shall have the burden of proof and the burden of persuasion by clear and convincing evidence. 
 (i) The
termination of any Proceeding or of any claim, issue or matter therein, by judgment, order, settlement or conviction, or upon a plea of nolo contendere or its equivalent, shall not (except as otherwise expressly provided in this Agreement) of itself
adversely affect the right of Indemnitee to indemnification or create a presumption that Indemnitee did not act in good faith and in a manner which he or she reasonably believed to be in or not opposed to the best interests of the Company or, with
respect to any criminal Proceeding, that Indemnitee had reasonable cause to believe that his or her conduct was unlawful. 
 7. REMEDIES OF
INDEMNITEE. 
 (a) In the event that: (i) a determination is made pursuant to Section 6 of this Agreement that
Indemnitee is not entitled to indemnification under this Agreement; (ii) advancement of Expenses is not timely made pursuant to Section 5 of this Agreement; (iii) no determination of entitlement to indemnification is made
pursuant to Section 6(b) of this Agreement within ninety (90) days after receipt by the Company of the request for indemnification; (iv) payment of indemnification is not made pursuant to this Agreement within ten
(10) days after receipt by the Company of a written request therefor; or (v) payment of indemnification is not made within ten (10) days after a determination has been made that Indemnitee is entitled to indemnification or such
determination is deemed to have been made pursuant to Section 6 of this Agreement, Indemnitee shall be entitled to an adjudication in any 

  
 7 








 
court of competent jurisdiction of Indemnitee’s entitlement to such indemnification. Indemnitee shall commence such proceeding seeking an adjudication within one hundred eighty
(180) days following the date on which Indemnitee first has the right to commence such proceeding pursuant to this Section 7(a). The Company shall not oppose Indemnitee’s right to seek any such adjudication. 

(b) In the event that a determination shall have been made pursuant to Section 6(b) of this Agreement that Indemnitee is
not entitled to indemnification, any judicial proceeding commenced pursuant to this Section 7 shall be conducted in all respects as a de novo trial on the merits, and Indemnitee shall not be prejudiced by reason of the adverse
determination under Section 6(b). 
 (c) If a determination shall have been made pursuant to Section 6(b) of
this Agreement that Indemnitee is entitled to indemnification, the Company shall be bound by such determination in any judicial proceeding commenced pursuant to this Section 7, absent: (i) a misstatement by Indemnitee of a material
fact or an omission of a material fact necessary to make Indemnitee’s misstatement not materially misleading in connection with the application for indemnification; or (ii) a prohibition of such indemnification under applicable law. 

(d) In the event that Indemnitee, pursuant to this Section 7, seeks a judicial adjudication of his or her rights under, or
to recover damages for breach of, this Agreement, or to recover under any directors’ and officers’ liability insurance policies maintained by the Company, the Company shall pay on his or her behalf, in advance, any and all expenses (of the
types described in the definition of “Expenses” in Section 13(g) of this Agreement) actually and reasonably incurred by him or her in such judicial adjudication, regardless of whether Indemnitee ultimately is determined to be
entitled to such indemnification, advancement of expenses or insurance recovery. 
 (e) The Company shall be precluded from asserting
in any judicial proceeding commenced pursuant to this Section 7 that the procedures and presumptions of this Agreement are not valid, binding and enforceable and shall stipulate in any such court that the Company is bound by all the
provisions of this Agreement. The Company shall indemnify Indemnitee against any and all Expenses and, if requested by Indemnitee, shall (within ten (10) days after receipt by the Company of a written request therefor) advance, to the extent
not prohibited by law, such expenses to Indemnitee, which are incurred by Indemnitee in connection with any action brought by Indemnitee for indemnification or advance of Expenses from the Company under this Agreement or under any directors’
and officers’ liability insurance policies maintained by the Company, regardless of whether Indemnitee ultimately is determined to be entitled to such indemnification, advancement of Expenses or insurance recovery, as the case may be. 

(f) Notwithstanding anything in this Agreement to the contrary, no determination as to entitlement to indemnification under this
Agreement shall be required to be made prior to the final disposition of the Proceeding. 

  
 8 








 8. NON-EXCLUSIVITY, SURVIVAL OF RIGHTS, ETC. 

(a) The rights of indemnification as provided by this Agreement shall not be deemed exclusive of any other rights to which Indemnitee
may at any time be entitled under applicable law, the organizational documents of the Company, any other agreement with the Company, a vote of the Company’s stockholders, a resolution of the Board or otherwise. No amendment, alteration or
repeal of this Agreement or of any provision hereof shall limit or restrict any right of Indemnitee under this Agreement in respect of any action taken or omitted by such Indemnitee in his or her Corporate Status prior to such amendment, alteration
or repeal. To the extent that a change in any applicable law, whether by statute or judicial decision, permits greater indemnification than would be afforded currently under the Company’s organizational documents and this Agreement, it is the
intent of the parties hereto that Indemnitee shall enjoy by this Agreement the greater benefits so afforded by such change. No right or remedy herein conferred is intended to be exclusive of any other right or remedy, and every other right and
remedy shall be cumulative and in addition to every other right and remedy given hereunder or now or hereafter existing at law or in equity or otherwise. The assertion or employment of any right or remedy hereunder, or otherwise, shall not prevent
the concurrent assertion or employment of any other right or remedy. 
 (b) To the extent that the Company maintains an insurance
policy or policies providing liability insurance for directors, officers, employees, or agents or fiduciaries of the Company or of any other Enterprise, Indemnitee shall be covered by such policy or policies in accordance with its or their terms to
the maximum extent of the coverage available for any director, officer, employee, agent or fiduciary under such policy or policies. If, at the time of the receipt of a notice of a claim pursuant to the terms hereof, the Company has directors’
and officers’ liability insurance in effect, the Company shall give prompt notice of the commencement of such proceeding to the insurers in accordance with the procedures set forth in the respective policies. The Company shall thereafter take
all necessary or desirable action to cause such insurers to pay, on behalf of the Indemnitee, all amounts payable as a result of such proceeding in accordance with the terms of such policies. 

(c) The Company hereby acknowledges that Indemnitee may have certain rights to indemnification, advancement of expenses and/or
insurance provided by the Associated Fund and/or certain of its affiliates (collectively, the “Additional Indemnitors”). The Company hereby agrees that: (i) it is the indemnitor of first resort (i.e., its obligations to
Indemnitee are primary and any obligation of the Additional Indemnitors (or any insurance carrier providing insurance coverage purchased by any Additional Indemnitor) to advance expenses or to provide indemnification for the same expenses or
liabilities incurred by Indemnitee are secondary); (ii) it shall be required to advance the full amount of expenses incurred by Indemnitee and shall be liable for the full amount of all Expenses, judgments, penalties, fines and amounts paid in
settlement to the extent legally permitted and as required by the terms of this Agreement and the organizational documents of the Company, without regard to any rights Indemnitee may have against the Additional Indemnitors (or any insurance carrier
providing insurance coverage purchased by any Additional Indemnitor); and (iii) it irrevocably waives, relinquishes and releases the Additional Indemnitors from any and all claims against the Additional Indemnitors for contribution, subrogation
or any other recovery of any kind in respect thereof. The Company further agrees that no advancement or payment by the Additional Indemnitors on behalf of 

  
 9 








 
Indemnitee with respect to any claim for which Indemnitee has sought indemnification from the Company shall affect the foregoing and the Additional Indemnitors shall have a right of
indemnification and/or be subrogated to the full extent of such advancement or payment to all of the rights of recovery of Indemnitee against the Company. The Company and Indemnitee agree that the Additional Indemnitors are express third party
beneficiaries of the terms of this Section 8(c). 
 (d) Except as provided in Section 8(c) above, in the event
of any payment under this Agreement, the Company shall be subrogated to the extent of such payment to all of the rights of recovery of Indemnitee (other than against the Additional Indemnitors), who shall execute all papers required and take all
action necessary to secure such rights, including execution of such documents as are necessary to enable the Company to bring suit to enforce such rights. 

(e) Except as provided in Section 8(c) above, the Company shall not be liable under this Agreement to make any payment of
amounts otherwise indemnifiable hereunder if and to the extent that Indemnitee has otherwise actually received payment of such amounts under any insurance policy, contract, other agreement or otherwise. 

(f) Except as provided in Section 8(c) above, the Company’s obligation to indemnify or advance Expenses hereunder to
Indemnitee who is or was serving at the request of the Company as a director, officer, employee or agent of any Enterprise other than the Company shall be reduced by any amount Indemnitee has actually received as indemnification or advancement of
expenses from such other Enterprise. 
 9. EXCEPTION TO RIGHT OF INDEMNIFICATION. Notwithstanding any provision in this Agreement, the Company shall
not be obligated under this Agreement to provide any indemnification in connection with any claim made against Indemnitee: (i) for which payment has actually been made to or on behalf of Indemnitee under any insurance policy or other indemnity
provision, except with respect to any excess beyond the amount paid under any insurance policy or other indemnity provision, provided that the foregoing shall not affect the rights of Indemnitee or the Additional Indemnitors set forth in
Section 8(c); (ii) for an accounting of profits made from the purchase and sale (or sale and purchase) by Indemnitee of securities of the Company within the meaning of Section 16(b) of the Exchange Act or similar provisions of
state statutory law or common law; or (iii) in connection with any Proceeding (or any part of any Proceeding) initiated by Indemnitee, including any Proceeding (or any part of any Proceeding) initiated by Indemnitee against the Company or its
directors, officers, employees or other indemnitees, unless (A) the Board authorized the Proceeding (or any part of any Proceeding) prior to its initiation or (B) the Company provides the indemnification, in its sole discretion, pursuant
to the powers vested in the Company under applicable law. 
 10. DURATION OF AGREEMENT. All agreements and obligations of the Company contained
herein shall continue until the date that is six (6) years after the date upon which Indemnitee’s Corporate Status terminates and shall continue thereafter so long as Indemnitee shall be subject to any Proceeding (or any proceeding
commenced under Section 7 hereof) by reason of his or her Corporate Status, whether or not he or she is acting or serving in any such capacity at the time any liability or expense is incurred for which indemnification can be provided
under this Agreement. This Agreement shall be binding upon and inure to the benefit 

  
 10 








 
of and be enforceable by the parties hereto and their respective successors (including any direct or indirect successor by purchase, merger, consolidation or otherwise to all or substantially all
of the business or assets of the Company), assigns, spouses, heirs, executors and personal and legal representatives. 
 11. SECURITY. To the extent
requested by Indemnitee and approved by the Board, the Company may at any time and from time to time provide security to Indemnitee for the Company’s obligations hereunder through an irrevocable bank line of credit, funded trust or other
collateral. Any such security, once provided to Indemnitee, may not be revoked or released without the prior written consent of the Indemnitee. 
 12.
ENFORCEMENT. The Company expressly confirms and agrees that it has entered into this Agreement and assumes the obligations imposed on it hereby in order to induce Indemnitee to serve as an officer or director of the Company, and the Company
acknowledges that Indemnitee is relying upon this Agreement in serving as an officer or director of the Company. The Company shall not seek from a court, or agree to, a “bar order” that would have the effect of prohibiting or limiting
Indemnitee’s rights to receive advancement of Expenses under this Agreement. 
 13. DEFINITIONS. For purposes of this Agreement: 

(a) “Beneficial Owner” shall have the meaning given to such term in
Rule 13d-3 under the Exchange Act; provided, however, that Beneficial Owner shall exclude any Person otherwise becoming a Beneficial Owner by reason of the stockholders of the Company
approving a merger of the Company with another entity. 
 (b) A “Change in Control” shall be deemed to occur
upon the earliest to occur after the date of this Agreement of any of the following events: 
 (i) any Person is or becomes the
Beneficial Owner, directly or indirectly, of securities of the Company representing fifteen percent (15%) or more of the combined voting power of the Company’s then outstanding securities; 

(ii) during any period of two (2) consecutive years (not including any period prior to the execution of this Agreement),
individuals who at the beginning of such period constitute the Board, and any new director (other than a director designated by a person who has entered into an agreement with the Company to effect a transaction described in
Sections 13(b)(i), (b)(iii) or (b)(iv)) whose election by the Board or nomination for election by the Company’s stockholders was approved by a vote of at least two-thirds of the directors then still in office who
either were directors at the beginning of the period or whose election or nomination for election was previously so approved, cease for any reason to constitute a least a majority of the members of the Board; 

(iii) the effective date of a merger or consolidation of the Company with any other entity, other than a merger or consolidation which
would result in the voting securities of the Company outstanding immediately prior to such merger or consolidation continuing to represent (either by remaining outstanding or by being converted into voting securities of the surviving entity) more
than fifty-one percent (51%) of the combined voting 

  
 11 








 
power of the voting securities of the surviving entity outstanding immediately after such merger or consolidation and with the power to elect at least a majority of the Board or other governing
body of such surviving entity; 
 (iv) the approval by the stockholders of the Company of a complete liquidation of the Company or
an agreement for the sale or disposition by the Company of all or substantially all of the Company’s assets; or 
 (v) there
occurs any other event of a nature that would be required to be reported in response to Item 6(e) of Schedule 14A of Regulation 14A (or a response to any similar item on any similar schedule or form) promulgated under the Exchange
Act, whether or not the Company is then subject to such reporting requirement. 
 (c)
“Corporate Status” describes the status of a person who is or was at any time (including, without limitation, any time prior to the date of this Agreement) a director, officer, employee, agent or fiduciary
of the Company or of any other corporation, partnership, joint venture, trust, employee benefit plan or other enterprise that such person is or was serving at the express written request of the Company. 

(d) “Disinterested Director” means a director of the Company who is not and was not
a party to the Proceeding in respect of which indemnification is sought by Indemnitee. 
 (e)
“Enterprise” shall mean the Company and any other corporation, partnership, joint venture, trust, employee benefit plan or other enterprise that Indemnitee is or was serving at the express written request of
the Company as a director, officer, employee, agent or fiduciary. 
 (f) “Exchange Act” shall
mean the Securities Exchange Act of 1934, as amended. 
 (g) “Expenses” shall
include all reasonable attorneys’ fees, retainers, court costs, transcript costs, fees of experts, witness fees, travel expenses, duplicating costs, printing and binding costs, telephone charges, postage, delivery service fees and all other
disbursements or expenses of the types customarily incurred in connection with prosecuting, defending, preparing to prosecute or defend, investigating, participating, or being or preparing to be a witness in a Proceeding, or responding to, or
objecting to, a request to provide discovery in any Proceeding. Expenses also shall include Expenses incurred in connection with any appeal resulting from any Proceeding and any federal, state, local or foreign taxes imposed on the Indemnitee as a
result of the actual or deemed receipt of any payments under this Agreement, including without limitation the premium, security for, and other costs relating to any cost bond, supersede as bond, or other appeal bond or its equivalent. Expenses,
however, shall not include amounts paid in settlement by Indemnitee or the amount of judgments or fines against Indemnitee. 

(h) “Independent Counsel” means a law firm, or a member of a law firm, that is
experienced in matters of corporation law and neither presently is, nor in the past five years has been, retained to represent: (i) the Company or Indemnitee in any matter material to either such party (other than with respect to matters
concerning Indemnitee under this Agreement, or of other indemnitees under similar indemnification agreements), or (ii) any other party to the Proceeding giving rise to a claim for indemnification hereunder. Notwithstanding the foregoing, the
term “Independent Counsel” shall not include any person who, under the applicable standards  

  
 12 








 
of professional conduct then prevailing, would have a conflict of interest in representing either the Company or Indemnitee in an action to determine Indemnitee’s rights under this
Agreement. The Company agrees to pay the reasonable fees of the Independent Counsel referred to above and to fully indemnify such counsel against any and all Expenses, claims, liabilities and damages arising out of or relating to this Agreement or
its engagement pursuant hereto. 
 (i) “Person” shall have the meaning as set forth in Sections 13(d)
and 14(d) of the Exchange Act; provided, however, that Person shall exclude: (i) the Company; (ii) any trustee or other fiduciary holding securities under an employee benefit plan of the Company; and (iii) any
corporation owned, directly or indirectly, by the stockholders of the Company in substantially the same proportions as their ownership of stock of the Company. 

(j) “Proceeding” includes any threatened, pending or completed action, suit,
arbitration, alternate dispute resolution mechanism, investigation, inquiry, administrative hearing or any other actual, threatened or completed proceeding (including one pending on or before the date of this Agreement but excluding one initiated by
an Indemnitee pursuant to Section 7 of this Agreement to enforce his or her rights under this Agreement), whether brought by or in the right of the Company or otherwise and whether civil, criminal, administrative or investigative, in
which Indemnitee was, is or will be involved as a party or otherwise, by reason of the fact that Indemnitee is or was an officer or director of the Company, by reason of any action taken by him or her or of any inaction on his or her part while
acting as an officer or director of the Company, or by reason of the fact that he or she is or was serving at the request of the Company as a director, officer, employee, agent or fiduciary of another corporation, partnership, joint venture, trust
or other Enterprise, in each case whether or not he or she is acting or serving in any such capacity at the time any liability or expense is incurred for which indemnification can be provided under this Agreement. 

14. SEVERABILITY. The invalidity or unenforceability of any provision hereof shall in no way affect the validity or enforceability of any other
provision. Without limiting the generality of the foregoing, this Agreement is intended to confer upon Indemnitee indemnification rights to the fullest extent permitted by applicable laws. In the event any provision hereof conflicts with any
applicable law, such provision shall be deemed modified, consistent with the aforementioned intent, to the extent necessary to resolve such conflict. 

15. MODIFICATION AND WAIVER. No supplement, modification, termination or amendment of this Agreement shall be binding unless executed in writing by
both of the parties hereto. No waiver of any of the provisions of this Agreement shall be deemed or shall constitute a waiver of any other provisions hereof (whether or not similar) nor shall such waiver constitute a continuing waiver. 

16. NOTICE BY INDEMNITEE. Indemnitee agrees to promptly notify the Company in writing upon being served with or otherwise receiving any summons,
citation, subpoena, complaint, indictment, information or other document relating to any Proceeding or matter which may be subject to indemnification covered hereunder. The failure to so notify the Company shall not relieve the Company of any
obligation which it may have to Indemnitee under this Agreement or otherwise unless and only to the extent that such failure or delay materially prejudices the Company. 

  
 13 








 17. NOTICES. All notices and other communications given or made pursuant to this Agreement shall be in
writing and shall be deemed effectively given: (i) upon personal delivery to the party to be notified; (ii) when sent by confirmed electronic mail or facsimile if sent during normal business hours of the recipient, and if not so confirmed,
then on the next business day; (iii) five (5) business days after having been sent by registered or certified mail, return receipt requested, postage prepaid; or (iv) one business (1) day after deposit with a nationally
recognized overnight courier, specifying next day delivery, with written verification of receipt. All notices and other communications shall be sent: 
  

	 	(a)	To Indemnitee at the address set forth below Indemnitee’s signature hereto. 

  

	 	(b)	To the Company at: 

 Seres Therapeutics, Inc. 

215 First St. Ste 440 
 Cambridge,
MA 02142 
 Attention: Board of Directors 
 or
to such other address as may have been furnished to Indemnitee by the Company or to the Company by Indemnitee, as the case may be. 
 18. HEADINGS.
The headings of the paragraphs of this Agreement are inserted for convenience only and shall not be deemed to constitute part of this Agreement or to affect the construction thereof. 

19. GOVERNING LAW. This Agreement and the legal relations among the parties shall be governed by, and construed and enforced in accordance with, the
laws of the State of Delaware, without regard to its conflict of laws rules that would require application of the laws of any other jurisdiction. 
 20.
ENTIRE AGREEMENT. This Agreement constitutes the entire agreement between the parties hereto with respect to the subject matter hereof and supersedes all prior agreements and understandings, oral, written and implied, between the parties hereto
with respect to the subject matter hereof. 
 21. COUNTERPARTS. This Agreement may be executed in two (2) or more counterparts, each of which
shall be deemed an original, but all of which together shall constitute one and the same Agreement. This Agreement may also be executed and delivered by facsimile signature (or other similar electronic means) and in two (2) or more
counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument. 

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK] 

  
 14 








 IN WITNESS WHEREOF, the parties have caused this Agreement to be signed as of the day and year
first above written. 
  

			
	SERES THERAPEUTICS, INC.
		
	By:		  

	Name:		
	Title:		
	
	INDEMNITEE
	
	  

	Name:		
	Address:		


 [Signature Page to Indemnification Agreement]