Document:

EX-10.2

 Exhibit 10.2 

SERES THERAPEUTICS, INC. 

2015 INCENTIVE AWARD PLAN 

 

	I.	PURPOSE 

 The Plan’s purpose is to enhance the Company’s ability
to attract, retain and motivate persons who make (or are expected to make) important contributions to the Company by providing these individuals with equity ownership opportunities. Capitalized terms used in the Plan are defined in Section XI.

  

	II.	ELIGIBILITY 

 Service Providers are eligible to be granted Awards under
the Plan, subject to the limitations described herein. 
  

	III.	ADMINISTRATION AND DELEGATION 

 (a)
Administration. The Plan is administered by the Administrator. The Administrator has authority to determine which Service Providers receive Awards, grant Awards and set Award terms and conditions, subject to the conditions and
limitations in the Plan. The Administrator also has the authority to take all actions and make all determinations under the Plan, to interpret the Plan and Award Agreements and to adopt, amend and repeal Plan administrative rules, guidelines and
practices as it deems advisable. The Administrator may correct defects and ambiguities, supply omissions and reconcile inconsistencies in the Plan or any Award as it deems necessary or appropriate to administer the Plan and any Awards. The
Administrator’s determinations under the Plan are in its sole discretion and will be final and binding on all persons having or claiming any interest in the Plan or any Award. 

(b) Appointment of Committees. To the extent Applicable Laws permit, the Board may delegate any or all of its powers under the
Plan to one or more Committees. The Board may abolish any Committee or re-vest in itself any previously delegated authority at any time. 
  

	IV.	STOCK AVAILABLE FOR AWARDS 

(a) Number of Shares. Subject to adjustment under Section VIII and the terms of this Section IV, Awards may be made
under the Plan covering up to the Overall Share Limit. As of the Plan’s effective date under Section X(c), the Company will cease granting awards under the Prior Plans; however, Prior Plan Awards will remain subject to the terms of the
applicable Prior Plan. Shares issued under the Plan may consist of authorized but unissued Shares, Shares purchased on the open market or treasury Shares. 

(b) Share Recycling. If all or any part of an Award or Prior Plan Award expires, lapses or is terminated, exchanged for cash,
surrendered, repurchased, canceled without having been fully exercised or forfeited, in any case, in a manner that results in the Company acquiring Shares covered by the Award or Prior Plan Award at a price not greater than the price (as adjusted to
reflect any Equity Restructuring) paid by the Participant for such Shares or not issuing any Shares covered by the Award or Prior Plan Award, the unused Shares covered by the Award or Prior Plan Award will, as applicable, become or again be
available for Award grants under the Plan. Further, Shares delivered (either by actual delivery or attestation) to the Company by a Participant to satisfy the applicable exercise or purchase price of an Award or Prior Plan Award and/or to satisfy
any applicable tax withholding obligation (including Shares retained by the Company from the Award or Prior Plan Award being exercised or purchased and/or 

 
creating the tax obligation) will, as applicable, become or again be available for Award grants under the Plan. The payment of Dividend Equivalents in cash in conjunction with any outstanding
Awards or Prior Plan Awards shall not count against the Overall Share Limit. 
 (c) Incentive Stock Option Limitations.
Notwithstanding anything to the contrary herein, no more than 17,200,000 Shares may be issued pursuant to the exercise of Incentive Stock Options. 

(d) Substitute Awards. In connection with an entity’s merger or consolidation with the Company or the Company’s acquisition
of an entity’s property or stock, the Administrator may grant Awards in substitution for any options or other stock or stock-based awards granted before such merger or consolidation by such entity or its affiliate. Substitute Awards may be
granted on such terms as the Administrator deems appropriate, notwithstanding limitations on Awards in the Plan. Substitute Awards will not count against the Overall Share Limit, except that Shares acquired by exercise of substitute Incentive Stock
Options will count against the maximum number of Shares that may be issued pursuant to the exercise of Incentive Stock Options under the Plan. 

(e) Non-Employee Director Compensation. Notwithstanding any provision to the contrary in the Plan, the Administrator may
establish compensation for non-employee Directors from time to time, subject to the limitations in the Plan. The Administrator will from time to time determine the terms, conditions and amounts of all such non-employee Director compensation in its
discretion and pursuant to the exercise of its business judgment, taking into account such factors, circumstances and considerations as it shall deem relevant from time to time, provided that the sum of any cash compensation, or other compensation,
and the value (determined as of the grant date in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 718, or any successor thereto) of Awards granted to a non-employee Director as compensation for services
as a non-employee Director during any fiscal year of the Company may not exceed $700,000. The Administrator may make exceptions to this limit for individual non-employee Directors in extraordinary circumstances, as the Administrator may determine in
its discretion, provided that the non-employee Director receiving such additional compensation may not participate in the decision to award such compensation or in other compensation decisions involving non-employee Directors. 

 

	V.	STOCK OPTIONS AND STOCK APPRECIATION RIGHTS 

(a) General. The Administrator may grant Options or Stock Appreciation Rights to Service Providers subject to the limitations in
the Plan, including Section IX(i) with respect to Incentive Stock Options. The Administrator will determine the number of Shares covered by each Option and Stock Appreciation Right, the exercise price of each Option and Stock Appreciation Right
and the conditions and limitations applicable to the exercise of each Option and Stock Appreciation Right. A Stock Appreciation Right will entitle the Participant (or other person entitled to exercise the Stock Appreciation Right) to receive from
the Company upon exercise of the exercisable portion of the Stock Appreciation Right an amount determined by multiplying the excess, if any, of the Fair Market Value of one Share on the date of exercise over the exercise price per Share of the Stock
Appreciation Right by the number of Shares with respect to which the Stock Appreciation Right is exercised, subject to any limitations of the Plan or that the Administrator may impose and payable in cash, Shares valued at Fair Market Value or a
combination of the two as the Administrator may determine or provide in the Award Agreement. 
 (b) Exercise Price. The
Administrator will establish each Option’s and Stock Appreciation Right’s exercise price and specify the exercise price in the Award Agreement. The exercise price will not be less than 100% of the Fair Market Value on the grant date of the
Option or Stock Appreciation Right. 

  
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 (c) Duration of Options. Each Option or Stock Appreciation Right will be
exercisable at such times and as specified in the Award Agreement, provided that the term of an Option or Stock Appreciation Right will not exceed ten years. 

(d) Exercise. Options and Stock Appreciation Rights may be exercised by delivering to the Company a written notice of exercise,
in a form the Administrator approves (which may be electronic), signed by the person authorized to exercise the Option or Stock Appreciation Right, together with, as applicable, payment in full (i) as specified in Section V(e) for the
number of Shares for which the Award is exercised and (ii) as specified in Section IX(e) for any applicable taxes. Unless the Administrator otherwise determines, an Option or Stock Appreciation Right may not be exercised for a fraction of
a Share. 
 (e) Payment Upon Exercise. The exercise price of an Option must be paid in cash, wire transfer of immediately
available funds or by check payable to the order of the Company or, subject to Section X(h), any Company insider trading policy (including blackout periods) and Applicable Laws, by: 

(i) if there is a public market for Shares at the time of exercise, unless the Administrator otherwise determines, (A) delivery
(including telephonically to the extent permitted by the Company) of an irrevocable and unconditional undertaking by a broker acceptable to the Company to deliver promptly to the Company sufficient funds to pay the exercise price, or (B) the
Participant’s delivery to the Company of a copy of irrevocable and unconditional instructions to a broker acceptable to the Company to deliver promptly to the Company cash or a check sufficient to pay the exercise price; provided that such
amount is paid to the Company at such time as may be required by the Administrator; 
 (ii) to the extent permitted by the Administrator,
delivery (either by actual delivery or attestation) of Shares owned by the Participant valued at their Fair Market Value; 
 (iii) to the
extent permitted by the Administrator, surrendering Shares then issuable upon the Option’s exercise valued at their Fair Market Value on the exercise date; 

(iv) to the extent permitted by the Administrator, delivery of a promissory note or any other property that the Administrator determines is
good and valuable consideration; or 
 (v) any combination of the above permitted payment forms (including cash, wire transfer or check).

  

	VI.	RESTRICTED STOCK; RESTRICTED STOCK UNITS 

(a) General. The Administrator may grant Restricted Stock, or the right to purchase Restricted Stock, to any Service Provider,
subject to the Company’s right to repurchase all or part of such shares at their issue price or other stated or formula price from the Participant (or to require forfeiture of such shares) if conditions the Administrator specifies in the Award
Agreement are not satisfied before the end of the applicable restriction period or periods that the Administrator establishes for such Award. In addition, the Administrator may grant to Service Providers Restricted Stock Units, which may be subject
to vesting and forfeiture conditions during the applicable restriction period or periods, as set forth in an Award Agreement. The Administrator will determine and set forth in the Award Agreement the terms and conditions for each Restricted Stock
and Restricted Stock Unit Award, subject to the conditions and limitations contained in the Plan. 

  
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 (b) Restricted Stock. 

(i) Dividends. Participants holding shares of Restricted Stock will be entitled to all ordinary cash dividends paid with respect to
such shares, unless the Administrator provides otherwise in the Award Agreement. In addition, unless the Administrator provides otherwise, if any dividends or distributions are paid in Shares, or consist of a dividend or distribution to holders of
Common Stock of property other than an ordinary cash dividend, the Shares or other property will be subject to the same restrictions on transferability and forfeitability as the shares of Restricted Stock with respect to which they were paid. 

(ii) Stock Certificates. The Company may require that the Participant deposit in escrow with the Company (or its designee) any stock
certificates issued in respect of shares of Restricted Stock, together with a stock power endorsed in blank. 
 (c) Restricted Stock
Units. 
 (i) Settlement. The Administrator may provide that settlement of Restricted Stock Units will occur upon or as
soon as reasonably practicable after the Restricted Stock Units vest or will instead be deferred, on a mandatory basis or at the Participant’s election, in a manner intended to comply with Section 409A. 

(ii) Stockholder Rights. A Participant will have no rights of a stockholder with respect to Shares subject to any Restricted Stock Unit
unless and until the Shares are delivered in settlement of the Restricted Stock Unit. 
 (iii) Dividend Equivalents. If the
Administrator provides, a grant of Restricted Stock Units may provide a Participant with the right to receive Dividend Equivalents. Dividend Equivalents may be paid currently or credited to an account for the Participant, settled in cash or Shares
and subject to the same restrictions on transferability and forfeitability as the Restricted Stock Units with respect to which the Dividend Equivalents are granted and subject to other terms and conditions as set forth in the Award Agreement. 

 

	VII.	OTHER STOCK OR CASH BASED AWARDS 

Other Stock or Cash Based Awards may be granted to Participants, including Awards entitling Participants to receive Shares to be delivered in
the future and including annual or other periodic or long-term cash bonus awards (whether based on specified Performance Criteria or otherwise), in each case subject to any conditions and limitations in the Plan. Such Other Stock or Cash Based
Awards will also be available as a payment form in the settlement of other Awards, as standalone payments and as payment in lieu of compensation to which a Participant is otherwise entitled. Other Stock or Cash Based Awards may be paid in Shares,
cash or other property, as the Administrator determines. Subject to the provisions of the Plan, the Administrator will determine the terms and conditions of each Other Stock or Cash Based Award, including any purchase price, performance goal (which
may be based on the Performance Criteria), transfer restrictions, and vesting conditions, which will be set forth in the applicable Award Agreement. 
  

	VIII.	ADJUSTMENTS FOR CHANGES IN COMMON STOCK AND CERTAIN OTHER EVENTS

 (a) Equity Restructuring. In connection with any Equity Restructuring, notwithstanding anything to the
contrary in this Section VIII, the Administrator will equitably adjust each outstanding Award as it deems appropriate to reflect the Equity Restructuring, which may include adjusting the 

  
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number and type of securities subject to each outstanding Award and/or the Award’s exercise price or grant price (if applicable), granting new Awards to Participants, and making a cash
payment to Participants. The adjustments provided under this Section VIII(a) will be nondiscretionary and final and binding on the affected Participant and the Company; provided that the Administrator will determine whether an adjustment is
equitable. 
 (b) Corporate Transactions. In the event of any dividend or other distribution (whether in the form of cash,
Common Stock, other securities, or other property), reorganization, merger, consolidation, combination, repurchase, recapitalization, liquidation, dissolution, or sale, transfer, exchange or other disposition of all or substantially all of the
assets of the Company, or sale or exchange of Common Stock or other securities of the Company, Change in Control, issuance of warrants or other rights to purchase Common Stock or other securities of the Company, other similar corporate transaction
or event, other unusual or nonrecurring transaction or event affecting the Company or its financial statements or any change in any Applicable Laws or accounting principles, the Administrator, on such terms and conditions as it deems appropriate,
either by the terms of the Award or by action taken prior to the occurrence of such transaction or event (except that action to give effect to a change in Applicable Law or accounting principles may be made within a reasonable period of time after
such change) and either automatically or upon the Participant’s request, is hereby authorized to take any one or more of the following actions whenever the Administrator determines that such action is appropriate in order to (x) prevent
dilution or enlargement of the benefits or potential benefits intended by the Company to be made available under the Plan or with respect to any Award granted or issued under the Plan, (y) to facilitate such transaction or event or
(z) give effect to such changes in Applicable Laws or accounting principles: 
 (i) To provide for the cancellation of any such Award
in exchange for either an amount of cash or other property with a value equal to the amount that could have been obtained upon the exercise or settlement of the vested portion of such Award or realization of the Participant’s rights under the
vested portion of such Award, as applicable; provided that, if the amount that could have been obtained upon the exercise or settlement of the vested portion of such Award or realization of the Participant’s rights, in any case, is equal to or
less than zero, then the Award may be terminated without payment; 
 (ii) To provide that such Award shall vest and, to the extent
applicable, be exercisable as to all shares covered thereby, notwithstanding anything to the contrary in the Plan or the provisions of such Award; 

(iii) To provide that such Award be assumed by the successor or survivor corporation, or a parent or subsidiary thereof, or shall be
substituted for by awards covering the stock of the successor or survivor corporation, or a parent or subsidiary thereof, with appropriate adjustments as to the number and kind of shares and/or applicable exercise or purchase price, in all cases, as
determined by the Administrator; 
 (iv) To make adjustments in the number and type of shares of Common Stock (or other securities or
property) subject to outstanding Awards and/or with respect to which Awards may be granted under the Plan (including, but not limited to, adjustments of the limitations in Section IV hereof on the maximum number and kind of shares which may be
issued) and/or in the terms and conditions of (including the grant or exercise price), and the criteria included in, outstanding Awards; 

(v) To replace such Award with other rights or property selected by the Administrator; and/or 

(vi) To provide that the Award will terminate and cannot vest, be exercised or become payable after the applicable event. 

  
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 (c) Administrative Stand Still. In the event of any pending stock dividend, stock
split, combination or exchange of shares, merger, consolidation or other distribution (other than normal cash dividends) of Company assets to stockholders, or any other extraordinary transaction or change affecting the Shares or the share price of
Common Stock, including any Equity Restructuring or any securities offering or other similar transaction, for administrative convenience, the Administrator may refuse to permit the exercise of any Award for up to sixty days before or after such
transaction. 
 (d) General. Except as expressly provided in the Plan or the Administrator’s action under the Plan, no
Participant will have any rights due to any subdivision or consolidation of Shares of any class, dividend payment, increase or decrease in the number of Shares of any class or dissolution, liquidation, merger, or consolidation of the Company or
other corporation. Except as expressly provided with respect to an Equity Restructuring under Section VIII(a) above or the Administrator’s action under the Plan, no issuance by the Company of Shares of any class, or securities convertible
into Shares of any class, will affect, and no adjustment will be made regarding, the number of Shares subject to an Award or the Award’s grant or exercise price. The existence of the Plan, any Award Agreements and the Awards granted hereunder
will not affect or restrict in any way the Company’s right or power to make or authorize (i) any adjustment, recapitalization, reorganization or other change in the Company’s capital structure or its business, (ii) any merger,
consolidation dissolution or liquidation of the Company or sale of Company assets or (iii) any sale or issuance of securities, including securities with rights superior to those of the Shares or securities convertible into or exchangeable for
Shares. The Administrator may treat Participants and Awards (or portions thereof) differently under this Section VIII. 
  

	IX.	GENERAL PROVISIONS APPLICABLE TO AWARDS. 

(a) Transferability. Except as the Administrator may determine or provide in an Award Agreement or otherwise for Awards other
than Incentive Stock Options, Awards may not be sold, assigned, transferred, pledged or otherwise encumbered, either voluntarily or by operation of law, except by will or the laws of descent and distribution, or, subject to the Administrator’s
consent, pursuant to a domestic relations order, and, during the life of the Participant, will be exercisable only by the Participant. References to a Participant, to the extent relevant in the context, will include references to a
Participant’s authorized transferee that the Administrator specifically approves. 
 (b) Documentation. Each Award will
be evidenced in an Award Agreement, which may be written or electronic, as the Administrator determines. Each Award may contain terms and conditions in addition to those set forth in the Plan. 

(c) Discretion. Except as the Plan otherwise provides, each Award may be made alone or in addition or in relation to any other
Award. The terms of each Award to a Participant need not be identical, and the Administrator need not treat Participants or Awards (or portions thereof) uniformly. 

(d) Termination of Status. The Administrator will determine how the disability, death, retirement, authorized leave of absence
or any other change or purported change in a Participant’s Service Provider status affects an Award and the extent to which, and the period during which, the Participant, the Participant’s legal representative, conservator, guardian or
Designated Beneficiary may exercise rights under the Award, if applicable. 
 (e) Withholding. Each Participant must pay the
Company, or make provision satisfactory to the Administrator for payment of, any taxes required by law to be withheld in connection with such 

  
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Participant’s Awards by the date of the event creating the tax liability. The Company may deduct an amount sufficient to satisfy such tax obligations based on the minimum statutory
withholding rates from any payment of any kind otherwise due to a Participant. Participants may satisfy such tax obligations in cash, by wire transfer of immediately available funds, by check made payable to the order of the Company, or subject to
Section X(h) and any Company insider trading policy (including blackout periods), (i) to the extent permitted by the Administrator, in whole or in part by delivery of Shares, including Shares retained from the Award creating the tax obligation,
valued at their Fair Market Value, (ii) if there is a public market for Shares at the time the tax obligations are satisfied, unless the Administrator otherwise determines, (A) delivery (including telephonically to the extent permitted by
the Company) of an irrevocable and unconditional undertaking by a broker acceptable to the Company to deliver promptly to the Company sufficient funds to satisfy the tax obligations, or (B) delivery by the Participant to the Company of a copy
of irrevocable and unconditional instructions to a broker acceptable to the Company to deliver promptly to the Company cash or a check sufficient to satisfy the tax withholding; provided that such amount is paid to the Company at such time as may be
required by the Administrator, or (iii) any combination of the foregoing permitted payment forms (including cash, wire transfer or check). If any tax withholding obligation will be satisfied under clause (i) of the immediately preceding
sentence by the Company’s retention of Shares from the Award creating the tax obligation and there is a public market for Shares at the time the tax obligation is satisfied, the Company may elect to instruct any brokerage firm determined
acceptable to the Company for such purpose to sell on the applicable Participant’s behalf some or all of the Shares retained and to remit the proceeds of the sale to the Company or its designee, and each Participant’s acceptance of an
Award under the Plan will constitute the Participant’s authorization to the Company and instruction and authorization to such brokerage firm to complete the transactions described in this sentence. 

(f) Amendment of Award; Repricing. The Administrator may amend, modify or terminate any outstanding Award, including by
substituting another Award of the same or a different type, changing the exercise or settlement date, and converting an Incentive Stock Option to a Non-Qualified Stock Option. The Participant’s consent to such action will be required unless
(i) the action, taking into account any related action, does not materially and adversely affect the Participant’s rights under the Award, or (ii) the change is permitted under Section VIII or pursuant to Section X(f).
Notwithstanding the foregoing or anything in the Plan to the contrary, the Administrator may, without the approval of the stockholders of the Company, reduce the exercise price per share of outstanding Options or Stock Appreciation Rights or cancel
outstanding Options or Stock Appreciation Rights in exchange for cash, other Awards or Options or Stock Appreciation Rights with an exercise price per share that is less than the exercise price per share of the original Options or Stock Appreciation
Rights. 
 (g) Conditions on Delivery of Stock. The Company will not be obligated to deliver any Shares under the Plan or
remove restrictions from Shares previously delivered under the Plan until (i) all Award conditions have been met or removed to the Company’s satisfaction, (ii) as determined by the Company, all other legal matters regarding the
issuance and delivery of such Shares have been satisfied, including any applicable securities laws and stock exchange or stock market rules and regulations, and (iii) the Participant has executed and delivered to the Company such
representations or agreements as the Administrator deems necessary or appropriate to satisfy any Applicable Laws. The Company’s inability to obtain authority from any regulatory body having jurisdiction, which the Administrator determines is
necessary to the lawful issuance and sale of any securities, will relieve the Company of any liability for failing to issue or sell such Shares as to which such requisite authority has not been obtained. 

(h) Acceleration. The Administrator may at any time provide that any Award will become immediately vested and fully or partially
exercisable, free of some or all restrictions or conditions, or otherwise fully or partially realizable. 

  
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 (i) Additional Terms of Incentive Stock Options. The Administrator may grant
Incentive Stock Options only to employees of the Company, any of its present or future parent or subsidiary corporations, as defined in Sections 424(e) or (f) of the Code, respectively, and any other entities the employees of which are eligible
to receive Incentive Stock Options under the Code. If an Incentive Stock Option is granted to a Greater Than 10% Stockholder, the exercise price will not be less than 110% of the Fair Market Value on the Option’s grant date, and the term of the
Option will not exceed five years. All Incentive Stock Options will be subject to and construed consistently with Section 422 of the Code. By accepting an Incentive Stock Option, the Participant agrees to give prompt notice to the Company of
dispositions or other transfers (other than in connection with a Change in Control) of Shares acquired under the Option made within (i) two years from the grant date of the Option or (ii) one year after the transfer of such Shares to the
Participant, specifying the date of the disposition or other transfer and the amount the Participant realized, in cash, other property, assumption of indebtedness or other consideration, in such disposition or other transfer. Neither the Company nor
the Administrator will be liable to a Participant, or any other party, if an Incentive Stock Option fails or ceases to qualify as an “incentive stock option” under Section 422 of the Code. Any Incentive Stock Option or portion thereof
that fails to qualify as an “incentive stock option” under Section 422 of the Code for any reason, including becoming exercisable with respect to Shares having a fair market value exceeding the $100,000 limitation under Treasury
Regulation Section 1.422-4, will be a Non-Qualified Stock Option. 
  

	X.	MISCELLANEOUS. 

 (a) No Right to Employment or Other Status.
No person will have any claim or right to be granted an Award, and the grant of an Award will not be construed as giving a Participant the right to continued employment or any other relationship with the Company. The Company expressly reserves
the right at any time to dismiss or otherwise terminate its relationship with a Participant free from any liability or claim under the Plan or any Award, except as expressly provided in an Award Agreement. 

(b) No Rights as Stockholder; Certificates. Subject to the Award Agreement, no Participant or Designated Beneficiary will have
any rights as a stockholder with respect to any Shares to be distributed under an Award until becoming the record holder of such Shares. Notwithstanding any other provision of the Plan, unless the Administrator otherwise determines or Applicable
Laws require, the Company will not be required to deliver to any Participant certificates evidencing Shares issued in connection with any Award and instead such Shares may be recorded in the books of the Company (or, as applicable, its transfer
agent or stock plan administrator). The Company may place legends on stock certificates issued under the Plan that the Administrator deems necessary or appropriate to comply with Applicable Laws. 

(c) Effective Date and Term of Plan. The Plan will become effective on the day prior to the Public Trading Date and will remain
in effect until the tenth anniversary of such date, unless earlier terminated by the Board. No Awards may be granted under the Plan during any suspension period or after Plan termination. Notwithstanding anything in the Plan to the contrary, an
Incentive Stock Option may not be granted under the Plan after ten years from the earlier of (i) the date the Board adopted the Plan or (ii) the date the Company’s stockholders approved the Plan, but Awards previously granted may
extend beyond that date in accordance with the Plan. If the Plan is not approved by the Company’s stockholders, (i) it will not become effective, (ii) no Awards shall be granted thereunder, and (iii) the Prior Plans will continue
in full force and effect in accordance with their terms. 
 (d) Amendment of Plan. The Administrator may amend, suspend or
terminate the Plan at any time; provided that no amendment, other than an increase to the Overall Share Limit, may materially and adversely affect any Award outstanding at the time of such amendment without the affected Participant’s consent.
Awards outstanding at the time of any Plan suspension or termination will continue 

  
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to be governed by the Plan and the Award Agreement, as in effect before such suspension or termination. The Board will obtain stockholder approval of any Plan amendment to the extent necessary to
comply with Applicable Laws. 
 (e) Provisions for Foreign Participants. The Administrator may modify Awards granted to
Participants who are foreign nationals or employed outside the United States or establish subplans or procedures under the Plan to address differences in laws, rules, regulations or customs of such foreign jurisdictions with respect to tax,
securities, currency, employee benefit or other matters. 
 (f) Section 409A. 

(i) General. The Company intends that all Awards be structured to comply with, or be exempt from, Section 409A, such that no
adverse tax consequences, interest, or penalties under Section 409A apply. Notwithstanding anything in the Plan or any Award Agreement to the contrary, the Administrator may, without a Participant’s consent, amend this Plan or Awards,
adopt policies and procedures, or take any other actions (including amendments, policies, procedures and retroactive actions) as are necessary or appropriate to preserve the intended tax treatment of Awards, including any such actions intended to
(A) exempt this Plan or any Award from Section 409A, or (B) comply with Section 409A, including regulations, guidance, compliance programs and other interpretative authority that may be issued after an Award’s grant date.
The Company makes no representations or warranties as to an Award’s tax treatment under Section 409A or otherwise. The Company will have no obligation under this Section X(f) or otherwise to avoid the taxes, penalties or interest
under Section 409A with respect to any Award and will have no liability to any Participant or any other person if any Award, compensation or other benefits under the Plan are determined to constitute noncompliant “nonqualified deferred
compensation” subject to taxes, penalties or interest under Section 409A. 
 (ii) Separation from Service. If an Award
constitutes “nonqualified deferred compensation” under Section 409A, any payment or settlement of such Award upon a termination of a Participant’s Service Provider relationship will, to the extent necessary to avoid taxes under
Section 409A, be made only upon the Participant’s “separation from service” (within the meaning of Section 409A), whether such “separation from service” occurs upon or after the termination of the
Participant’s Service Provider relationship. For purposes of this Plan or any Award Agreement relating to any such payments or benefits, references to a “termination,” “termination of employment” or like terms means a
“separation from service.” 
 (iii) Payments to Specified Employees. Notwithstanding any contrary provision in the Plan or
any Award Agreement, any payment(s) of “nonqualified deferred compensation” required to be made under an Award to a “specified employee” (as defined under Section 409A and as the Administrator determines) due to his or her
“separation from service” will, to the extent necessary to avoid taxes under Section 409A(a)(2)(B)(i) of the Code, be delayed for the six-month period immediately following such “separation from service” (or, if earlier,
until the specified employee’s death) and will instead be paid (as set forth in the Award Agreement) on the day immediately following such six-month period or as soon as administratively practicable thereafter (without interest). Any payments
of “nonqualified deferred compensation” under such Award payable more than six months following the Participant’s “separation from service” will be paid at the time or times the payments are otherwise scheduled to be made.

 (g) Limitations on Liability. Notwithstanding any other provisions of the Plan, no individual acting as a director,
officer, other employee or agent of the Company or any Subsidiary will be liable to any Participant, former Participant, spouse, beneficiary, or any other person for any claim, loss, liability, or expense incurred in connection with the Plan or any
Award, and such individual will not be personally liable with respect to the Plan because of any contract or other instrument executed in his or her capacity 

  
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as an Administrator, director, officer, other employee or agent of the Company or any Subsidiary. The Company will indemnify and hold harmless each director, officer, other employee and agent of
the Company or any Subsidiary that has been or will be granted or delegated any duty or power relating to the Plan’s administration or interpretation, against any cost or expense (including attorneys’ fees) or liability (including any sum
paid in settlement of a claim with the Administrator’s approval) arising from any act or omission concerning this Plan unless arising from such person’s own fraud or bad faith. 

(h) Lock-Up Period. The Company may, at the request of any underwriter representative or otherwise, in connection with
registering the offering of any Company securities under the Securities Act, prohibit Participants from, directly or indirectly, selling or otherwise transferring any Shares or other Company securities during a period of up to one hundred eighty
days following the effective date of a Company registration statement filed under the Securities Act, or such longer period as determined by the underwriter. 

(i) Data Privacy. As a condition for receiving any Award, each Participant explicitly and unambiguously consents to the collection, use
and transfer, in electronic or other form, of personal data as described in this paragraph by and among the Company and its Subsidiaries and affiliates exclusively for implementing, administering and managing the Participant’s participation in
the Plan. The Company and its Subsidiaries and affiliates may hold certain personal information about a Participant, including the Participant’s name, address and telephone number; birthdate; social security, insurance number or other
identification number; salary; nationality; job title(s); any Shares held in the Company or its Subsidiaries and affiliates; and Award details, to implement, manage and administer the Plan and Awards (the “Data”). The Company
and its Subsidiaries and affiliates may transfer the Data amongst themselves as necessary to implement, administer and manage a Participant’s participation in the Plan, and the Company and its Subsidiaries and affiliates may transfer the Data
to third parties assisting the Company with Plan implementation, administration and management. These recipients may be located in the Participant’s country, or elsewhere, and the Participant’s country may have different data privacy laws
and protections than the recipients’ country. By accepting an Award, each Participant authorizes such recipients to receive, possess, use, retain and transfer the Data, in electronic or other form, to implement, administer and manage the
Participant’s participation in the Plan, including any required Data transfer to a broker or other third party with whom the Company or the Participant may elect to deposit any Shares. The Data related to a Participant will be held only as long
as necessary to implement, administer, and manage the Participant’s participation in the Plan. A Participant may, at any time, view the Data that the Company holds regarding such Participant, request additional information about the storage and
processing of the Data regarding such Participant, recommend any necessary corrections to the Data regarding the Participant or refuse or withdraw the consents in this Section X(i) in writing, without cost, by contacting the local human
resources representative. The Company may cancel Participant’s ability to participate in the Plan and, in the Administrator’s discretion, the Participant may forfeit any outstanding Awards if the Participant refuses or withdraws the
consents in this Section X(i). For more information on the consequences of refusing or withdrawing consent, Participants may contact their local human resources representative. 

(j) Severability. If any portion of the Plan or any action taken under it is held illegal or invalid for any reason, the
illegality or invalidity will not affect the remaining parts of the Plan, and the Plan will be construed and enforced as if the illegal or invalid provisions had been excluded, and the illegal or invalid action will be null and void. 

(k) Governing Documents. If any contradiction occurs between the Plan and any Award Agreement or other written agreement between
a Participant and the Company (or any Subsidiary) that the Administrator has approved, the Plan will govern, unless it is expressly specified in such Award Agreement or other written document that a specific provision of the Plan will not apply.

  
 10 

 (l) Governing Law. The Plan and all Awards will be governed by and interpreted in
accordance with the laws of the State of Delaware, disregarding any state’s choice-of-law principles requiring the application of a jurisdiction’s laws other than the State of Delaware. 

(m) Claw-back Provisions. All Awards (including any proceeds, gains or other economic benefit the Participant actually or
constructively receives upon receipt or exercise of any Award or the receipt or resale of any Shares underlying the Award) will be subject to any Company claw-back policy, including any claw-back policy adopted to comply with Applicable Laws
(including the Dodd-Frank Wall Street Reform and Consumer Protection Act and any rules or regulations promulgated thereunder) as set forth in such claw-back policy or the Award Agreement. 

(n) Titles and Headings. The titles and headings in the Plan are for convenience of reference only and, if any conflict, the
Plan’s text, rather than such titles or headings, will control. 
 (o) Conformity to Securities Laws. Participant acknowledges
that the Plan is intended to conform to the extent necessary with Applicable Laws. Notwithstanding anything herein to the contrary, the Plan and all Awards will be administered only in conformance with Applicable Laws. To the extent Applicable Laws
permit, the Plan and all Award Agreements will be deemed amended as necessary to conform to Applicable Laws. 
 (p) Relationship to Other
Benefits. No payment under the Plan will be taken into account in determining any benefits under any pension, retirement, savings, profit sharing, group insurance, welfare or other benefit plan of the Company or any Subsidiary except as
expressly provided in writing in such other plan or an agreement thereunder. 
 (q) Broker-Assisted Sales. In the event of a
broker-assisted sale of Shares in connection with the payment of amounts owed by a Participant under or with respect to the Plan or Awards, including amounts to be paid under the final sentence of Section IX(e): (a) any Shares to be sold
through the broker-assisted sale will be sold on the day the payment first becomes due, or as soon thereafter as practicable; (b) such Shares may be sold as part of a block trade with other Participants in the Plan in which all participants
receive an average price; (c) the applicable Participant will be responsible for all broker’s fees and other costs of sale, and by accepting an Award, each Participant agrees to indemnify and hold the Company harmless from any losses,
costs, damages, or expenses relating to any such sale; (d) to the extent the Company or its designee receives proceeds of such sale that exceed the amount owed, the Company will pay such excess in cash to the applicable Participant as soon as
reasonably practicable; (e) the Company and its designees are under no obligation to arrange for such sale at any particular price; and (f) in the event the proceeds of such sale are insufficient to satisfy the Participant’s
applicable obligation, the Participant may be required to pay immediately upon demand to the Company or its designee an amount in cash sufficient to satisfy any remaining portion of the Participant’s obligation. 

 

	XI.	DEFINITIONS 

 As used in the Plan, the following words and phrases will
have the following meanings: 
 (a) “Administrator” means the Board or a Committee to the extent that the
Board’s powers or authority under the Plan have been delegated to such Committee. 
 (b) “Applicable Laws”
means the requirements relating to the administration of equity incentive plans under U.S. federal and state securities, tax and other applicable laws, rules and regulations, the applicable rules of any stock exchange or quotation system on which
the Common Stock is listed or quoted and the applicable laws and rules of any foreign country or other jurisdiction where Awards are granted. 

  
 11 

 (c) “Award” means, individually or collectively, a grant under the Plan
of Options, Stock Appreciation Rights, Restricted Stock, Restricted Stock Units or Other Stock or Cash Based Awards. 
 (d)
“Award Agreement” means a written agreement evidencing an Award, which may be electronic, that contains such terms and conditions as the Administrator determines, consistent with and subject to the terms and conditions of the
Plan. 
 (e) “Board” means the Board of Directors of the Company. 

(f) “Change in Control” means and includes each of the following: 

(i) A transaction or series of transactions (other than an offering of Common Stock to the general public through a registration statement
filed with the Securities and Exchange Commission or a transaction or series of transactions that meets the requirements of clauses (A) and (B) of subsection (iii) below) whereby any “person” or related “group” of
“persons” (as such terms are used in Sections 13(d) and 14(d)(2) of the Exchange Act) (other than the Company, any of its Subsidiaries, an employee benefit plan maintained by the Company or any of its Subsidiaries or a “person”
that, prior to such transaction, directly or indirectly controls, is controlled by, or is under common control with, the Company) directly or indirectly acquires beneficial ownership (within the meaning of Rule 13d-3 under the Exchange Act) of
securities of the Company possessing more than 50% of the total combined voting power of the Company’s securities outstanding immediately after such acquisition; or 

(ii) During any period of two consecutive years, individuals who, at the beginning of such period, constitute the Board together with any new
Director(s) (other than a Director designated by a person who shall have entered into an agreement with the Company to effect a transaction described in subsections (i) or (iii)) 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 two-year period or whose election or nomination for election was previously so
approved, cease for any reason to constitute a majority thereof; or 
 (iii) The consummation by the Company (whether directly involving the
Company or indirectly involving the Company through one or more intermediaries) of (x) a merger, consolidation, reorganization, or business combination or (y) a sale or other disposition of all or substantially all of the Company’s
assets in any single transaction or series of related transactions or (z) the acquisition of assets or stock of another entity, in each case other than a transaction: 

(A) which results in the Company’s voting securities outstanding immediately before the transaction continuing to
represent (either by remaining outstanding or by being converted into voting securities of the Company or the person that, as a result of the transaction, controls, directly or indirectly, the Company or owns, directly or indirectly, all or
substantially all of the Company’s assets or otherwise succeeds to the business of the Company (the Company or such person, the “Successor Entity”)) directly or indirectly, at least a majority of the combined voting
power of the Successor Entity’s outstanding voting securities immediately after the transaction, and 
 (B) after which
no person or group beneficially owns voting securities representing 50% or more of the combined voting power of the Successor Entity; provided, however, that no person or group shall be treated for purposes of this clause (B)

  
 12 

 
as beneficially owning 50% or more of the combined voting power of the Successor Entity solely as a result of the voting power held in the Company prior to the consummation of the transaction.

 Notwithstanding the foregoing, if a Change in Control constitutes a payment event with respect to any Award (or portion of any Award) that provides for
the deferral of compensation that is subject to Section 409A, to the extent required to avoid the imposition of additional taxes under Section 409A, the transaction or event described in subsection (i), (ii) or (iii) with
respect to such Award (or portion thereof) shall only constitute a Change in Control for purposes of the payment timing of such Award if such transaction also constitutes a “change in control event,” as defined in Treasury Regulation
Section 1.409A-3(i)(5). 
 The Administrator shall have full and final authority, which shall be exercised in its discretion, to determine conclusively
whether a Change in Control has occurred pursuant to the above definition, the date of the occurrence of such Change in Control and any incidental matters relating thereto; provided that any exercise of authority in conjunction with a determination
of whether a Change in Control is a “change in control event” as defined in Treasury Regulation Section 1.409A-3(i)(5) shall be consistent with such regulation. 

(g) “Code” means the Internal Revenue Code of 1986, as amended, and the regulations issued thereunder. 

(h) “Committee” means one or more committees or subcommittees of the Board, which may include one or
more Company directors or executive officers, to the extent Applicable Laws permit. To the extent required to comply with the provisions of Rule 16b-3, it is intended that each member of the Committee will be, at the time the Committee takes any
action with respect to an Award that is subject to Rule 16b-3, a “non-employee director” within the meaning of Rule 16b-3; however, a Committee member’s failure to qualify as a “non-employee director” within the meaning of
Rule 16b-3 will not invalidate any Award granted by the Committee that is otherwise validly granted under the Plan.  
 (i)
“Common Stock” means the common stock of the Company. 
 (j) “Company” means Seres
Therapeutics, Inc., a Delaware corporation, or any successor. 
 (k) “Consultant” means any person,
including any adviser, engaged by the Company or its parent or Subsidiary to render services to such entity if the consultant or adviser: (i) renders bona fide services to the Company; (ii) renders
services not in connection with the offer or sale of securities in a capital-raising transaction and does not directly or indirectly promote or maintain a market for the Company’s securities; and (iii) is a natural person.

 (l) “Designated Beneficiary” means the beneficiary or beneficiaries the Participant
designates, in a manner the Administrator determines, to receive amounts due or exercise the Participant’s rights if the Participant dies or becomes incapacitated. Without a Participant’s effective designation, “Designated
Beneficiary” will mean the Participant’s estate. 
 (m) “Director” means a Board member.

 (n) “Disability” means a permanent and total disability under Section 22(e)(3) of the Code, as amended. 

  
 13 

 (o) “Dividend Equivalents” means a right granted to a
Participant under the Plan to receive the equivalent value (in cash or Shares) of dividends paid on Shares. 
 (p)
“Employee” means any employee of the Company or its Subsidiaries. 
 (q) “Equity
Restructuring” means a nonreciprocal transaction between the Company and its stockholders, such as a stock dividend, stock split, spin-off or recapitalization through a large, nonrecurring cash dividend, that affects the number or kind
of Shares (or other Company securities) or the share price of Common Stock (or other Company securities) and causes a change in the per share value of the Common Stock underlying outstanding Awards. 

(r) “Exchange Act” means the Securities Exchange Act of 1934, as amended. 

(s) “Fair Market Value” means, as of any date, the value of Common Stock determined as follows:
(i) if the Common Stock is listed on any established stock exchange, its Fair Market Value will be the closing sales price for such Common Stock as quoted on such exchange for such date, or if no sale occurred on such date, the last day
preceding such date during which a sale occurred, as reported in The Wall Street Journal or another source the Administrator deems reliable; (ii) if the Common Stock is not traded on a stock exchange but is quoted on a national market or
other quotation system, the closing sales price on such date, or if no sales occurred on such date, then on the last date preceding such date during which a sale occurred, as reported in The Wall Street Journal or another source the
Administrator deems reliable; or (iii) without an established market for the Common Stock, the Administrator will determine the Fair Market Value in its discretion. 

(t) “Greater Than 10% Stockholder” means an individual then owning (within the meaning of
Section 424(d) of the Code) more than 10% of the total combined voting power of all classes of stock of the Company or its parent or subsidiary corporation, as defined in Section 424(e) and (f) of the Code, respectively.

 (u) “Incentive Stock Option” means an Option intended to qualify as an “incentive
stock option” as defined in Section 422 of the Code. 
 (v) “Non-Qualified Stock Option”
means an Option not intended or not qualifying as an Incentive Stock Option. 
 (w) “Option” means an option to
purchase Shares. 
 (x) “Other Stock or Cash Based Awards” means cash awards, awards of Shares, and
other awards valued wholly or partially by referring to, or are otherwise based on, Shares or other property. 

(y) “Overall Share Limit” means the sum of (i) 2,200,000 Shares; (ii) any shares of Common
Stock which are subject to Prior Plan Awards which become available for issuance under the Plan pursuant to Section IV(b) and (iii) an annual increase on the first day of each calendar year beginning January 1, 2016 and ending on and
including January 1, 2025, equal to the lesser of (A) 4% of the aggregate number of shares of Common Stock outstanding on the final day of the immediately preceding calendar year and (B) such smaller number of Shares as is determined
by the Board. 
 (z) “Participant” means a Service Provider who has been granted an Award. 

(aa) “Performance Criteria” mean the criteria (and adjustments) that the Administrator may select for an Award to
establish performance goals for a performance period, which may include the 

  
 14 

 
following: net earnings or losses (either before or after one or more of interest, taxes, depreciation, amortization, and non-cash equity-based compensation expense); gross or net sales or
revenue or sales or revenue growth; net income (either before or after taxes) or adjusted net income; profits (including but not limited to gross profits, net profits, profit growth, net operation profit or economic profit), profit return ratios or
operating margin; budget or operating earnings (either before or after taxes or before or after allocation of corporate overhead and bonus); cash flow (including operating cash flow and free cash flow or cash flow return on capital); return on
assets; return on capital or invested capital; cost of capital; return on stockholders’ equity; total stockholder return; return on sales; costs, reductions in costs and cost control measures; expenses; working capital; earnings or loss per
share; adjusted earnings or loss per share; price per share or dividends per share (or appreciation in or maintenance of such price or dividends); regulatory achievements or compliance; implementation, completion or attainment of objectives relating
to research, development, regulatory, commercial, or strategic milestones or developments; market share; economic value or economic value added models; division, group or corporate financial goals; customer satisfaction/growth; customer service;
employee satisfaction; recruitment and maintenance of personnel; human resources management; supervision of litigation and other legal matters; strategic partnerships and transactions; financial ratios (including those measuring liquidity, activity,
profitability or leverage); debt levels or reductions; sales-related goals; financing and other capital raising transactions; cash on hand; acquisition activity; investment sourcing activity; and marketing initiatives, any of which may be measured
in absolute terms or as compared to any incremental increase or decrease, peer group results, or market performance indicators or indices. 

(bb) “Plan” means this 2015 Incentive Award Plan. 

(cc) “Prior Plans” means, collectively, the Seres Health, Inc. 2012 Stock Incentive Plan and any prior
equity incentive plans of the Company or its predecessor. 
 (dd) “Prior Plan Award”
means an award outstanding under the Prior Plans as of the Plan’s effective date in Section X(c). 

(ee) “Public Trading Date” means the first date upon which the Common Stock is listed (or approved for
listing) upon notice of issuance on any securities exchange or designated (or approved for designation) upon notice of issuance as a national market security on an interdealer quotation system, or, if earlier, the date on which the Company becomes a
“publicly held corporation” for purposes of Treasury Regulation Section 1.162-27(c)(1). 
 (ff)
“Restricted Stock” means Shares awarded to a Participant under Section VI subject to certain vesting conditions and other restrictions. 

(gg) “Restricted Stock Unit” means an unfunded, unsecured right to receive, on the applicable settlement
date, one Share or an amount in cash or other consideration determined by the Administrator to be of equal value as of such settlement date, subject to certain vesting conditions and other restrictions. 

(hh) “Rule 16b-3” means Rule 16b-3 promulgated under the Exchange Act. 

(ii) “Section 409A” means Section 409A of the Code and all regulations, guidance, compliance
programs and other interpretative authority thereunder. 
 (jj) “Securities Act” means the Securities
Act of 1933, as amended. 
 (kk) “Service Provider” means an Employee, Consultant or Director. 

  
 15 

 (ll) “Shares” means shares of Common Stock. 

(mm) “Stock Appreciation Right” means a stock appreciation right granted under Section V. 

(nn) “Subsidiary” means any entity (other than the Company), whether domestic or foreign, in an unbroken
chain of entities beginning with the Company if each of the entities other than the last entity in the unbroken chain beneficially owns, at the time of the determination, securities or interests representing at least 50% of the total combined voting
power of all classes of securities or interests in one of the other entities in such chain. 
 (oo) “Termination of
Service” means the date the Participant ceases to be a Service Provider. 
 * * * * * 

  
 16 

 SERES HEALTH, INC. 

2015 INCENTIVE AWARD PLAN 

RESTRICTED STOCK UNIT GRANT NOTICE 

Capitalized terms not specifically defined in this Restricted Stock Unit Grant Notice (the “Grant
Notice”) have the meanings given to them in the 2015 Incentive Award Plan (as amended from time to time, the “Plan”) of Seres Health, Inc. (the “Company”). 

The Company hereby grants to the participant listed below (“Participant”) the Restricted Stock Units described in this
Grant Notice (the “RSUs”), subject to the terms and conditions of the Plan and the Restricted Stock Unit Agreement attached hereto as Exhibit A (the “Agreement”), both of which are incorporated
into this Grant Notice by reference. 
  

			
	Participant:		
		
	Grant Date:		
		
	Number of RSUs:		
		
	Vesting Commencement Date:		
		
	Vesting Schedule:		 [To be specified in individual award agreements]

 By Participant’s signature below, Participant agrees to be bound by the terms of this Grant Notice, the
Plan and the Agreement. Participant has reviewed the Plan, this Grant Notice and the Agreement in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Grant Notice and fully understands all provisions of the
Plan, this Grant Notice and the Agreement. Participant hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Administrator upon any questions arising under the Plan, this Grant Notice or the Agreement. 

 

									
	SERES HEALTH, INC.				PARTICIPANT
					
	By:		  
				By:		  

					
	Print Name:		  
				Print Name:		  

					
	Title:		  
						

 Exhibit A 

RESTRICTED STOCK UNIT AGREEMENT 

Capitalized terms not specifically defined in this Agreement have the meanings specified in the Grant Notice or, if not defined in the Grant
Notice, in the Plan. 
 ARTICLE I. 

GENERAL 
 1.1 Award of
RSUs and Dividend Equivalents. 
 (a) The Company has granted the RSUs to Participant effective as of the grant date set forth in the
Grant Notice (the “Grant Date”). Each RSU represents the right to receive one Share or, at the option of the Company, an amount of cash, in either case, as set forth in this Agreement. Participant will have no right to the
distribution of any Shares or payment of any cash until the time (if ever) the RSUs have vested. 
 (b) The Company hereby grants to
Participant, with respect to each RSU, a Dividend Equivalent for ordinary cash dividends paid to substantially all holders of outstanding Shares with a record date after the Grant Date and prior to the date the applicable RSU is settled, forfeited
or otherwise expires. Each Dividend Equivalent entitles Participant to receive the equivalent value of any such ordinary cash dividends paid on a single Share. The Company will establish a separate Dividend Equivalent bookkeeping account (a
“Dividend Equivalent Account”) for each Dividend Equivalent and credit the Dividend Equivalent Account (without interest) on the applicable dividend payment date with the amount of any such cash paid. 

1.2 Incorporation of Terms of Plan. The RSUs are subject to the terms and conditions set forth in this Agreement and the Plan, which is
incorporated herein by reference. In the event of any inconsistency between the Plan and this Agreement, the terms of the Plan will control. 

1.3 Unsecured Promise. The RSUs and Dividend Equivalents will at all times prior to settlement represent an unsecured Company
obligation payable only from the Company’s general assets. 
 ARTICLE II. 

VESTING; FORFEITURE AND SETTLEMENT 

2.1 Vesting; Forfeiture. The RSUs will vest according to the vesting schedule in the Grant Notice except that any fraction of an RSU
that would otherwise be vested will be accumulated and will vest only when a whole RSU has accumulated. In the event of Participant’s Termination of Service for any reason, all unvested RSUs will immediately and automatically be cancelled and
forfeited, except as otherwise determined by the Administrator or provided in a binding written agreement between Participant and the Company. Dividend Equivalents (including any Dividend Equivalent Account balance) will vest or be forfeited, as
applicable, upon the vesting or forfeiture of the RSU with respect to which the Dividend Equivalent (including the Dividend Equivalent Account) relates. 

2.2 Settlement. 
 (a)
RSUs and Dividend Equivalents (including any Dividend Equivalent Account balance) will be paid in Shares or cash at the Company’s option as soon as administratively practicable after the vesting of the applicable RSU, but in no event more than
sixty (60) days after the RSU’s vesting date. Notwithstanding the foregoing, the Company may delay any payment under this Agreement that the Company reasonably determines would violate Applicable Law until the earliest date the Company

 
reasonably determines the making of the payment will not cause such a violation (in accordance with Treasury Regulation Section 1.409A-2(b)(7)(ii)), provided the Company reasonably believes
the delay will not result in the imposition of excise taxes under Section 409A. 
 (b) If an RSU is paid in cash, the amount of cash
paid with respect to the RSU will equal the Fair Market Value of a Share on the day immediately preceding the payment date. If a Dividend Equivalent is paid in Shares, the number of Shares paid with respect to the Dividend Equivalent will equal the
quotient, rounded down to the nearest whole Share, of the Dividend Equivalent Account balance divided by the Fair Market Value of a Share on the day immediately preceding the payment date. 

ARTICLE III. 
 TAXATION
AND TAX WITHHOLDING 
 3.1 Representation. Participant represents to the Company that Participant has reviewed with
Participant’s own tax advisors the tax consequences of this Award and the transactions contemplated by the Grant Notice and this Agreement. Participant is relying solely on such advisors and not on any statements or representations of the
Company or any of its agents. 
 3.2 Tax Withholding. 

(a) The Company has the right and option, but not the obligation, to treat Participant’s failure to provide timely payment in accordance
with the Plan of any withholding tax arising in connection with the RSUs or Dividend Equivalents as Participant’s election to satisfy all or any portion of the withholding tax by requesting the Company retain Shares otherwise issuable under the
Award. 
 (b) Participant acknowledges that Participant is ultimately liable and responsible for all taxes owed in connection with the RSUs
and the Dividend Equivalents, regardless of any action the Company or any Subsidiary takes with respect to any tax withholding obligations that arise in connection with the RSUs or Dividend Equivalents. Neither the Company nor any Subsidiary makes
any representation or undertaking regarding the treatment of any tax withholding in connection with the awarding, vesting or payment of the RSUs or the Dividend Equivalents or the subsequent sale of Shares. The Company and the Subsidiaries do not
commit and are under no obligation to structure the RSUs or Dividend Equivalents to reduce or eliminate Participant’s tax liability. 

ARTICLE IV. 
 OTHER
PROVISIONS 
 4.1 Adjustments. Participant acknowledges that the RSUs, the Shares subject to the RSUs and the Dividend
Equivalents are subject to adjustment, modification and termination in certain events as provided in this Agreement and the Plan. 
 4.2
Notices. Any notice to be given under the terms of this Agreement to the Company must be in writing and addressed to the Company in care of the Company’s Secretary at the Company’s principal office or the Secretary’s
then-current email address or facsimile number. Any notice to be given under the terms of this Agreement to Participant must be in writing and addressed to Participant at Participant’s last known mailing address, email address or facsimile
number in the Company’s personnel files. By a notice given pursuant to this Section, either party may designate a different address for notices to be given to that party. Any notice will be deemed duly given when actually received, when sent by
email, when sent by certified mail (return receipt requested) and deposited with postage prepaid in a post office or branch post office regularly maintained by the United States Postal Service, when delivered by a nationally recognized express
shipping company or upon receipt of a facsimile transmission confirmation. 

  
 A-2 

 4.3 Titles. Titles are provided herein for convenience only and are not to serve as a
basis for interpretation or construction of this Agreement. 
 4.4 Conformity to Securities Laws. Participant acknowledges that the
Plan, the Grant Notice and this Agreement are intended to conform to the extent necessary with all Applicable Laws and, to the extent Applicable Laws permit, will be deemed amended as necessary to conform to Applicable Laws. 

4.5 Successors and Assigns. The Company may assign any of its rights under this Agreement to single or multiple assignees, and this
Agreement will inure to the benefit of the successors and assigns of the Company. Subject to the restrictions on transfer set forth in the Plan, this Agreement will be binding upon and inure to the benefit of the heirs, legatees, legal
representatives, successors and assigns of the parties hereto. 
 4.6 Limitations Applicable to Section 16 Persons.
Notwithstanding any other provision of the Plan or this Agreement, if Participant is subject to Section 16 of the Exchange Act, the Plan, the Grant Notice, this Agreement, the RSUs and the Dividend Equivalents will be subject to any additional
limitations set forth in any applicable exemptive rule under Section 16 of the Exchange Act (including any amendment to Rule 16b-3) that are requirements for the application of such exemptive rule. To the extent Applicable Laws permit, this
Agreement will be deemed amended as necessary to conform to such applicable exemptive rule. 
 4.7 Entire Agreement. The Plan, the
Grant Notice and this Agreement (including any exhibit hereto) constitute the entire agreement of the parties and supersede in their entirety all prior undertakings and agreements of the Company and Participant with respect to the subject matter
hereof. 
 4.8 Agreement Severable. In the event that any provision of the Grant Notice or this Agreement is held illegal or invalid,
the provision will be severable from, and the illegality or invalidity of the provision will not be construed to have any effect on, the remaining provisions of the Grant Notice or this Agreement. 

4.9 Limitation on Participant’s Rights. Participation in the Plan confers no rights or interests other than as herein provided.
This Agreement creates only a contractual obligation on the part of the Company as to amounts payable and may not be construed as creating a trust. Neither the Plan nor any underlying program, in and of itself, has any assets. Participant will have
only the rights of a general unsecured creditor of the Company with respect to amounts credited and benefits payable, if any, with respect to the RSUs and Dividend Equivalents, and rights no greater than the right to receive cash or the Shares as a
general unsecured creditor with respect to the RSUs and Dividend Equivalents, as and when settled pursuant to the terms of this Agreement. 

4.10 Not a Contract of Employment. Nothing in the Plan, the Grant Notice or this Agreement confers upon Participant any right to
continue in the employ or service of the Company or any Subsidiary or interferes with or restricts in any way the rights of the Company and its Subsidiaries, which rights are hereby expressly reserved, to discharge or terminate the services of
Participant at any time for any reason whatsoever, with or without Cause, except to the extent expressly provided otherwise in a written agreement between the Company or a Subsidiary and Participant. 

4.11 Counterparts. The Grant Notice may be executed in one or more counterparts, including by way of any electronic signature, subject
to Applicable Law, each of which will be deemed an original and all of which together will constitute one instrument. 

* * * * * 

  
 A-3 

 SERES HEALTH, INC. 

2015 INCENTIVE AWARD PLAN 

RESTRICTED STOCK GRANT NOTICE 

Capitalized terms not specifically defined in this Restricted Stock Grant Notice (the “Grant Notice”) have the
meanings given to them in the 2015 Incentive Award Plan (as amended from time to time, the “Plan”) of Seres Health, Inc. (the “Company”). 

The Company has granted to the participant listed below (“Participant”) the shares of Restricted Stock
described in this Grant Notice (the “Restricted Shares”), subject to the terms and conditions of the Plan and the Restricted Stock Agreement attached as Exhibit A (the
“Agreement”), both of which are incorporated into this Grant Notice by reference. 
  

			
	Participant:		
		
	Grant Date:		
		
	Number of Restricted Shares:		
		
	Vesting Commencement Date:		
		
	Vesting Schedule:		 [To be specified in individual award agreements]

 By Participant’s signature below, Participant agrees to be bound by the terms of this Grant Notice, the
Plan and the Agreement. Participant has reviewed the Plan, this Grant Notice and the Agreement in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Grant Notice and fully understands all provisions of the
Plan, this Grant Notice and the Agreement. Participant hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Administrator upon any questions arising under the Plan, this Grant Notice or the Agreement. 

 

									
	SERES HEALTH, INC.				PARTICIPANT
					
	By:		  
				By:		  

					
	Print Name:		  
				Print Name:		  

					
	Title:		  
						

 Exhibit A 

RESTRICTED STOCK AGREEMENT 

Capitalized terms not specifically defined in this Agreement have the meanings specified in the Grant Notice or, if not defined in the Grant
Notice, in the Plan. 
 ARTICLE I. 

GENERAL 
 1.1 Issuance
of Restricted Shares. The Company will issue the Restricted Shares to the Participant effective as of the grant date set forth in the Grant Notice and will cause (a) a stock certificate or certificates representing the Restricted Shares to
be registered in Participant’s name or (b) the Restricted Shares to be held in book-entry form. If a stock certificate is issued, the certificate will be delivered to, and held in accordance with this Agreement by, the Company or its
authorized representatives and will bear the restrictive legends required by this Agreement. If the Restricted Shares are held in book-entry form, then the book-entry will indicate that the Restricted Shares are subject to the restrictions of this
Agreement. 
 1.2 Incorporation of Terms of Plan. The Restricted Shares are subject to the terms and conditions set forth in this
Agreement and the Plan, which is incorporated herein by reference. In the event of any inconsistency between the Plan and this Agreement, the terms of the Plan will control. 

ARTICLE II. 
 VESTING,
FORFEITURE AND ESCROW 
 2.1 Vesting. The Restricted Shares will become vested Shares (the “Vested
Shares”) according to the vesting schedule in the Grant Notice except that any fraction of a Share that would otherwise become a Vested Share will be accumulated and will become a Vested Share only when a whole Vested Share has
accumulated. 
 2.2 Forfeiture. In the event of Participant’s Termination of Service for any reason, Participant will
immediately and automatically forfeit to the Company any Shares that are not Vested Shares (the “Unvested Shares”) at the time of Participant’s Termination of Service, except as otherwise determined by the Administrator
or provided in a binding written agreement between Participant and the Company. Upon forfeiture of Unvested Shares, the Company will become the legal and beneficial owner of the Unvested Shares and all related interests and Participant will have no
further rights with respect to the Unvested Shares. 
 2.3 Escrow. 

(a) Unvested Shares will be held by the Company or its authorized representatives until (i) they are forfeited, (ii) they become
Vested Shares or (iii) this Agreement is no longer in effect. By accepting this Award, Participant appoints the Company and its authorized representatives as Participant’s attorney(s)-in-fact to take all actions necessary to effect any
transfer of forfeited Unvested Shares (and Retained Distributions (as defined below), if any, paid on such forfeited Unvested Shares) to the Company as may be required pursuant to the Plan or this Agreement and to execute such representations or
other documents or assurances as the Company or such representatives deem necessary or advisable in connection with any such transfer. The Company, or its authorized representative, will not be liable for any good faith act or omission with respect
to the holding in escrow or transfer of the Restricted Shares. 

 (b) All cash dividends and other distributions made or declared with respect to Unvested Shares
(“Retained Distributions”) will be held by the Company until the time (if ever) when the Unvested Shares to which such Retained Distributions relate become Vested Shares. The Company will establish a separate Retained
Distribution bookkeeping account (“Retained Distribution Account”) for each Unvested Share with respect to which Retained Distributions have been made or declared in cash and credit the Retained Distribution Account (without
interest) on the date of payment with the amount of such cash made or declared with respect to the Unvested Share. Retained Distributions (including any Retained Distribution Account balance) will immediately and automatically be forfeited upon
forfeiture of the Unvested Share with respect to which the Retained Distributions were paid or declared. 
 (c) As soon as reasonably
practicable following the date on which an Unvested Share becomes a Vested Share, the Company will (i) cause the certificate (or a new certificate without the legend required by this Agreement, if Participant so requests) representing the Share
to be delivered to Participant or, if the Share is held in book-entry form, cause the notations indicating the Share is subject to the restrictions of this Agreement to be removed and (ii) pay to Participant the Retained Distributions relating
to the Share. 
 2.4 Rights as Stockholder. Except as otherwise provided in this Agreement or the Plan, upon issuance of the
Restricted Shares by the Company, Participant will have all the rights of a stockholder with respect to the Restricted Shares, including the right to vote the Restricted Shares and to receive dividends or other distributions paid or made with
respect to the Restricted Shares. 
 ARTICLE III. 

TAXATION AND TAX WITHHOLDING 

3.1 Representation. Participant represents to the Company that Participant has reviewed with Participant’s own tax advisors the
tax consequences of the Restricted Shares and the transactions contemplated by the Grant Notice and this Agreement. Participant is relying solely on such advisors and not on any statements or representations of the Company or any of its agents. 

3.2 Section 83(b) Election. If Participant makes an election under Section 83(b) of the Code with respect to the Restricted
Shares, Participant will deliver a copy of the election to the Company promptly after filing the election with the Internal Revenue Service. 

3.3 Tax Withholding. 

(a) The Company has the right and option, but not the obligation, to treat Participant’s failure to provide timely payment in accordance
with the Plan of any withholding tax arising in connection with the Restricted Shares as Participant’s election to satisfy all or any portion of the withholding tax by requesting the Company retain Shares otherwise deliverable under the Award.

 (b) Participant acknowledges that Participant is ultimately liable and responsible for all taxes owed in connection with the Restricted
Shares, regardless of any action the Company or any Subsidiary takes with respect to any tax withholding obligations that arise in connection with the Restricted Shares. Neither the Company nor any Subsidiary makes any representation or undertaking
regarding the treatment of any tax withholding in connection with the awarding, vesting or payment of the Restricted Shares or the subsequent sale of the Restricted Shares. The Company and the Subsidiaries do not commit and are under no obligation
to structure this Award to reduce or eliminate Participant’s tax liability. 

  
 A-2 

 ARTICLE IV. 

RESTRICTIVE LEGENDS AND TRANSFERABILITY 

4.1 Legends. Any certificate representing a Restricted Share will bear the following legend until the Restricted Share becomes a Vested
Share: 
 THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO FORFEITURE IN FAVOR OF THE COMPANY AND MAY BE TRANSFERRED ONLY IN
ACCORDANCE WITH THE TERMS OF A RESTRICTED STOCK AGREEMENT BETWEEN THE COMPANY AND THE STOCKHOLDER, A COPY OF WHICH IS ON FILE WITH THE SECRETARY OF THE COMPANY. 

4.2 Transferability. The Restricted Shares and any Retained Distributions are subject to the restrictions on transfer in the Plan and
may not be sold, assigned or transferred in any manner unless and until they become Vested Shares. Any attempted transfer or disposition of Unvested Shares or related Retained Distributions prior to the time the Unvested Shares become Vested Shares
will be null and void. The Company will not be required to (a) transfer on its books any Restricted Share that has been sold or otherwise transferred in violation of this Agreement or (b) treat as owner of such Restricted Share or accord
the right to vote or pay dividends to any purchaser or other transferee to whom such Restricted Share has been so transferred. The Company may issue appropriate “stop transfer” instructions to its transfer agent, if any, or make
appropriate notations to the same effect in its records. 
 ARTICLE V. 

OTHER PROVISIONS 
 5.1
Adjustments. Participant acknowledges that the Restricted Shares are subject to adjustment, modification and termination in certain events as provided in this Agreement and the Plan. 

5.2 Notices. Any notice to be given under the terms of this Agreement to the Company must be in writing and addressed to the Company in
care of the Company’s Secretary at the Company’s principal office or the Secretary’s then-current email address or facsimile number. Any notice to be given under the terms of this Agreement to Participant must be in writing and
addressed to Participant at Participant’s last known mailing address, email address or facsimile number in the Company’s personnel files. By a notice given pursuant to this Section, either party may designate a different address for
notices to be given to that party. Any notice will be deemed duly given when actually received, when sent by email, when sent by certified mail (return receipt requested) and deposited with postage prepaid in a post office or branch post office
regularly maintained by the United States Postal Service, when delivered by a nationally recognized express shipping company or upon receipt of a facsimile transmission confirmation. 

5.3 Titles. Titles are provided herein for convenience only and are not to serve as a basis for interpretation or construction of this
Agreement. 
 5.4 Conformity to Securities Laws. Participant acknowledges that the Plan, the Grant Notice and this Agreement are
intended to conform to the extent necessary with all Applicable Laws and, to the extent Applicable Laws permit, will be deemed amended as necessary to conform to Applicable Laws. 

5.5 Successors and Assigns. The Company may assign any of its rights under this Agreement to single or multiple assignees, and this
Agreement will inure to the benefit of the successors and assigns of the Company. Subject to the restrictions on transfer set forth in this Agreement or the Plan, this Agreement will be binding upon and inure to the benefit of the heirs, legatees,
legal representatives, successors and assigns of the parties hereto. 

  
 A-3 

 5.6 Limitations Applicable to Section 16 Persons. Notwithstanding any other provision
of the Plan or this Agreement, if Participant is subject to Section 16 of the Exchange Act, the Plan, the Grant Notice, this Agreement and the Restricted Shares will be subject to any additional limitations set forth in any applicable exemptive
rule under Section 16 of the Exchange Act (including any amendment to Rule 16b-3) that are requirements for the application of such exemptive rule. To the extent Applicable Laws permit, this Agreement will be deemed amended as necessary to
conform to such applicable exemptive rule. 
 5.7 Entire Agreement. The Plan, the Grant Notice and this Agreement (including any
exhibit hereto) constitute the entire agreement of the parties and supersede in their entirety all prior undertakings and agreements of the Company and Participant with respect to the subject matter hereof. 

5.8 Agreement Severable. In the event that any provision of the Grant Notice or this Agreement is held illegal or invalid, the
provision will be severable from, and the illegality or invalidity of the provision will not be construed to have any effect on, the remaining provisions of the Grant Notice or this Agreement. 

5.9 Limitation on Participant’s Rights. Participation in the Plan confers no rights or interests other than as herein provided.
This Agreement creates only a contractual obligation on the part of the Company as to amounts payable and may not be construed as creating a trust. Neither the Plan nor any underlying program, in and of itself, has any assets. Participant will have
only the rights of a general unsecured creditor of the Company with respect to amounts credited and benefits payable, if any, with respect to the Award. 

5.10 Not a Contract of Employment. Nothing in the Plan, the Grant Notice or this Agreement confers upon Participant any right to
continue in the employ or service of the Company or any Subsidiary or interferes with or restricts in any way the rights of the Company and its Subsidiaries, which rights are hereby expressly reserved, to discharge or terminate the services of
Participant at any time for any reason whatsoever, with or without cause, except to the extent expressly provided otherwise in a written agreement between the Company or a Subsidiary and Participant. 

5.11 Counterparts. The Grant Notice may be executed in one or more counterparts, including by way of any electronic signature, subject
to Applicable Law, each of which will be deemed an original and all of which together will constitute one instrument. 

* * * * * 

  
 A-4 

 SERES HEALTH, INC. 

2015 INCENTIVE AWARD PLAN 

STOCK OPTION GRANT NOTICE 

Capitalized terms not specifically defined in this Stock Option Grant Notice (the “Grant Notice”) have
the meanings given to them in the 2015 Incentive Award Plan (as amended from time to time, the “Plan”) of Seres Health, Inc. (the “Company”). 

The Company hereby grants to the participant listed below (“Participant”) the stock option described in
this Grant Notice (the “Option”), subject to the terms and conditions of the Plan and the Stock Option Agreement attached hereto as Exhibit A (the “Agreement”),
both of which are incorporated into this Grant Notice by reference. 
  

			
	Participant:		
		
	Grant Date:		
		
	Exercise Price per Share:		
		
	Shares Subject to the Option:		
		
	Final Expiration Date:		
		
	Vesting Commencement Date:		
		
	Vesting Schedule:		 [To be specified in individual award agreements]

		
	Type of Option		  ̈  Incentive Stock
Option       ̈  Non-Qualified Stock Option

 By Participant’s signature below, Participant agrees to be bound by the terms of this Grant Notice, the
Plan and the Agreement. Participant has reviewed the Plan, this Grant Notice and the Agreement in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Grant Notice and fully understands all provisions of the
Plan, this Grant Notice and the Agreement. Participant hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Administrator upon any questions arising under the Plan, this Grant Notice or the Agreement. 

 

									
	SERES HEALTH, INC.				PARTICIPANT
					
	By:		  
				By:		  

					
	Print Name:		  
				Print Name:		  

					
	Title:		  
						

 Exhibit A 

STOCK OPTION AGREEMENT 

Capitalized terms not specifically defined in this Agreement have the meanings specified in the Grant Notice or, if not defined in the Grant
Notice, in the Plan. 
 ARTICLE I. 

GENERAL 
 1.1 Grant of
Option. Pursuant to the Grant Notice to which this Agreement is attached, the Company has granted to Participant the Option effective as of the grant date set forth in the Grant Notice (the “Grant Date”). 

1.2 Incorporation of Terms of Plan. The Option is subject to the terms and conditions set forth in this Agreement and the Plan, which
is incorporated herein by reference. In the event of any inconsistency between the Plan and this Agreement, the terms of the Plan will control. 

ARTICLE II. 
 PERIOD OF
EXERCISABILITY 
 2.1 Commencement of Exercisability. The Option will vest and become exercisable according to the vesting
schedule in the Grant Notice (the “Vesting Schedule”) except that any fraction of a Share as to which the Option would be vested or exercisable will be accumulated and will vest and become exercisable only when a whole Share
has accumulated. Notwithstanding anything in the Grant Notice, the Plan or this Agreement to the contrary, unless the Administrator otherwise determines, the Option will immediately expire and be forfeited as to any portion that is not vested and
exercisable as of Participant’s Termination of Service for any reason. 
 2.2 Duration of Exercisability. The Vesting Schedule
is cumulative. Any portion of the Option which vests and becomes exercisable will remain vested and exercisable until the Option expires. The Option will be forfeited immediately upon its expiration. 

2.3 Expiration of Option. The Option may not be exercised to any extent by anyone after, and will expire on, the first of the following
to occur: 
 (a) The final expiration date in the Grant Notice; 

(b) Except as the Administrator may otherwise approve, the expiration of three (3) months from the date of Participant’s Termination
of Service, unless Participant’s Termination of Service is for Cause or by reason of Participant’s death or Disability; 
 (c)
Except as the Administrator may otherwise approve, the expiration of one (1) year from the date of Participant’s Termination of Service by reason of Participant’s death or Disability; and 

(d) Except as the Administrator may otherwise approve, Participant’s Termination of Service for Cause. 

As used in this Agreement, “Cause” means (i) if Participant is a party to a written employment or consulting agreement with the
Company or its Subsidiary in which the term “cause” is defined (a “Relevant Agreement”), “Cause” as defined in the Relevant Agreement, and (ii) if no Relevant Agreement exists, (A) the
Administrator’s determination that Participant failed to substantially perform 

 
Participant’s duties (other than a failure resulting from Participant’s Disability); (B) the Administrator’s determination that Participant failed to carry out, or comply with
any lawful and reasonable directive of the Board or Participant’s immediate supervisor; (C) Participant’s conviction, plea of no contest, plea of nolo contendere, or imposition of unadjudicated probation for any felony or indictable
offense or crime involving moral turpitude; (D) Participant’s unlawful use (including being under the influence) or possession of illegal drugs on the premises of the Company or any of its Subsidiaries or while performing
Participant’s duties and responsibilities for the Company or any of its Subsidiaries; or (E) Participant’s commission of an act of fraud, embezzlement, misappropriation, misconduct, or breach of fiduciary duty against the Company or
any of its Subsidiaries. 
 ARTICLE III. 

EXERCISE OF OPTION 
 3.1
Person Eligible to Exercise. During Participant’s lifetime, only Participant may exercise the Option. After Participant’s death, any exercisable portion of the Option may, prior to the time the Option expires, be exercised by
Participant’s Designated Beneficiary as provided in the Plan. 
 3.2 Partial Exercise. Any exercisable portion of the Option or
the entire Option, if then wholly exercisable, may be exercised, in whole or in part, according to the procedures in the Plan at any time prior to the time the Option or portion thereof expires, except that the Option may only be exercised for whole
Shares. 
 3.3 Tax Withholding. 

(a) The Company has the right and option, but not the obligation, to treat Participant’s failure to provide timely payment in accordance
with the Plan of any withholding tax arising in connection with the Option as Participant’s election to satisfy all or any portion of the withholding tax by requesting the Company retain Shares otherwise issuable under the Option. 

(b) Participant acknowledges that Participant is ultimately liable and responsible for all taxes owed in connection with the Option,
regardless of any action the Company or any Subsidiary takes with respect to any tax withholding obligations that arise in connection with the Option. Neither the Company nor any Subsidiary makes any representation or undertaking regarding the
treatment of any tax withholding in connection with the awarding, vesting or exercise of the Option or the subsequent sale of Shares. The Company and the Subsidiaries do not commit and are under no obligation to structure the Option to reduce or
eliminate Participant’s tax liability. 
 ARTICLE IV. 

OTHER PROVISIONS 
 4.1
Adjustments. Participant acknowledges that the Option is subject to adjustment, modification and termination in certain events as provided in this Agreement and the Plan. 

4.2 Notices. Any notice to be given under the terms of this Agreement to the Company must be in writing and addressed to the Company in
care of the Company’s Secretary at the Company’s principal office or the Secretary’s then-current email address or facsimile number. Any notice to be given under the terms of this Agreement to Participant must be in writing and
addressed to Participant (or, if Participant is then deceased, to the person entitled to exercise the Option) at Participant’s last known mailing address, email address or facsimile number in the Company’s personnel files. By a notice
given pursuant to this Section, either party may designate a different address for notices to be given to that party. Any notice will be deemed duly given when actually received, when sent by email, when sent by 

  
 A-2 

 
certified mail (return receipt requested) and deposited with postage prepaid in a post office or branch post office regularly maintained by the United States Postal Service, when delivered by a
nationally recognized express shipping company or upon receipt of a facsimile transmission confirmation. 
 4.3 Titles. Titles are
provided herein for convenience only and are not to serve as a basis for interpretation or construction of this Agreement. 
 4.4
Conformity to Securities Laws. Participant acknowledges that the Plan, the Grant Notice and this Agreement are intended to conform to the extent necessary with all Applicable Laws and, to the extent Applicable Laws permit, will be deemed
amended as necessary to conform to Applicable Laws. 
 4.5 Successors and Assigns. The Company may assign any of its rights under
this Agreement to single or multiple assignees, and this Agreement will inure to the benefit of the successors and assigns of the Company. Subject to the restrictions on transfer set forth in the Plan, this Agreement will be binding upon and inure
to the benefit of the heirs, legatees, legal representatives, successors and assigns of the parties hereto. 
 4.6 Limitations Applicable
to Section 16 Persons. Notwithstanding any other provision of the Plan or this Agreement, if Participant is subject to Section 16 of the Exchange Act, the Plan, the Grant Notice, this Agreement and the Option will be subject to any
additional limitations set forth in any applicable exemptive rule under Section 16 of the Exchange Act (including any amendment to Rule 16b-3) that are requirements for the application of such
exemptive rule. To the extent Applicable Laws permit, this Agreement will be deemed amended as necessary to conform to such applicable exemptive rule. 

4.7 Entire Agreement. The Plan, the Grant Notice and this Agreement (including any exhibit hereto) constitute the entire agreement
of the parties and supersede in their entirety all prior undertakings and agreements of the Company and Participant with respect to the subject matter hereof. 

4.8 Agreement Severable. In the event that any provision of the Grant Notice or this Agreement is held illegal or invalid, the
provision will be severable from, and the illegality or invalidity of the provision will not be construed to have any effect on, the remaining provisions of the Grant Notice or this Agreement. 

4.9 Limitation on Participant’s Rights. Participation in the Plan confers no rights or interests other than as herein provided.
This Agreement creates only a contractual obligation on the part of the Company as to amounts payable and may not be construed as creating a trust. Neither the Plan nor any underlying program, in and of itself, has any assets. Participant will have
only the rights of a general unsecured creditor of the Company with respect to amounts credited and benefits payable, if any, with respect to the Option, and rights no greater than the right to receive the Shares as a general unsecured creditor with
respect to the Option, as and when exercised pursuant to the terms hereof. 
 4.10 Not a Contract of Employment. Nothing in the Plan,
the Grant Notice or this Agreement confers upon Participant any right to continue in the employ or service of the Company or any Subsidiary or interferes with or restricts in any way the rights of the Company and its Subsidiaries, which rights are
hereby expressly reserved, to discharge or terminate the services of Participant at any time for any reason whatsoever, with or without Cause, except to the extent expressly provided otherwise in a written agreement between the Company or a
Subsidiary and Participant. 

  
 A-3 

 4.11 Counterparts. The Grant Notice may be executed in one or more counterparts, including
by way of any electronic signature, subject to Applicable Law, each of which will be deemed an original and all of which together will constitute one instrument. 

4.12 Incentive Stock Options. If the Option is designated as an Incentive Stock Option: 

(a) Participant acknowledges that to the extent the aggregate fair market value of shares (determined as of the time the option with respect
to the shares is granted) with respect to which stock options intended to qualify as “incentive stock options” under Section 422 of the Code, including the Option, are exercisable for the first time by Participant during any calendar
year exceeds $100,000 or if for any other reason such stock options do not qualify or cease to qualify for treatment as “incentive stock options” under Section 422 of the Code, such stock options (including the Option) will be treated
as non-qualified stock options. Participant further acknowledges that the rule set forth in the preceding sentence will be applied by taking the Option and other stock options into account in the order in which they were granted, as determined under
Section 422(d) of the Code. Participant also acknowledges that if the Option is exercised more than three (3) months after Participant’s Termination of Service, other than by reason of death or disability, the Option will be taxed as
a Non-Qualified Stock Option. 
 (b) Participant will give prompt written notice to the Company of any disposition or other transfer of any
Shares acquired under this Agreement if such disposition or other transfer is made (a) within two (2) years from the Grant Date or (b) within one (1) year after the transfer of such Shares to Participant. Such notice will specify
the date of such disposition or other transfer and the amount realized, in cash, other property, assumption of indebtedness or other consideration, by Participant in such disposition or other transfer. 

* * * * * 

  
 A-4EX-10.3

 Exhibit 10.3 

SERES THERAPEUTICS, INC. 

2015 EMPLOYEE STOCK PURCHASE PLAN 

 

	I.	PURPOSE 

 The purposes of this Seres Therapeutics, Inc. 2015 Employee
Stock Purchase Plan (as it may be amended or restated from time to time, the “Plan”) are to assist Eligible Employees of Seres Therapeutics, Inc., a Delaware corporation (the “Company”), and its
Designated Subsidiaries in acquiring a stock ownership interest in the Company pursuant to a plan which is intended to qualify as an “employee stock purchase plan” within the meaning of Section 423(b) of the Code, and to help Eligible
Employees provide for their future security and to encourage them to remain in the employment of the Company and its Designated Subsidiaries. 
  

	II.	DEFINITIONS AND CONSTRUCTION 

 Wherever the
following terms are used in the Plan they shall have the meanings specified below, unless the context clearly indicates otherwise. The singular pronoun shall include the plural where the context so indicates. Masculine, feminine and neuter pronouns
are used interchangeably and each comprehends the others. 
 (a) “Administrator” shall mean the entity that conducts
the general administration of the Plan as provided in Section XI. The term “Administrator” shall refer to the Committee unless the Board has assumed the authority for administration of the Plan as provided in Section XI. 

(b) “Applicable Laws” shall mean the requirements relating to the administration of equity incentive plans under U.S.
federal and state securities, tax and other applicable laws, rules and regulations, the applicable rules of any stock exchange or quotation system on which the Common Stock is listed or quoted and the applicable laws and rules of any foreign country
or other jurisdiction where rights under this Plan are granted. 
 (c) “Board” shall mean the Board of Directors of
the Company. 
 (d) “Change in Control” shall mean and include each of the following: 

(i) A transaction or series of transactions (other than an offering of Common Stock to the general public through a registration statement
filed with the Securities and Exchange Commission or a transaction or series of transactions that meets the requirements of clauses (A) and (B) of Section II(d)(iii) below) whereby any “person” or related “group”
of “persons” (as such terms are used in Sections 13(d) and 14(d)(2) of the Exchange Act) (other than the Company, any of its Subsidiaries, an employee benefit plan maintained by the Company or any of its Subsidiaries or a
“person” that, prior to such transaction, directly or indirectly controls, is controlled by, or is under common control with, the Company) directly or indirectly acquires beneficial ownership (within the meaning of Rule 13d-3 under the
Exchange Act) of securities of the Company possessing more than 50% of the total combined voting power of the Company’s securities outstanding immediately after such acquisition; or 

 (ii) During any period of two consecutive years, individuals who, at the beginning of such
period, constitute the Board together with any new director(s) (other than a director designated by a person who shall have entered into an agreement with the Company to effect a transaction described in Section II(d)(i) or II(d)(iii)) 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 two-year period or whose
election or nomination for election was previously so approved, cease for any reason to constitute a majority thereof; or 
 (iii) The
consummation by the Company (whether directly involving the Company or indirectly involving the Company through one or more intermediaries) of (x) a merger, consolidation, reorganization, or business combination or (y) a sale or other
disposition of all or substantially all of the Company’s assets in any single transaction or series of related transactions or (z) the acquisition of assets or stock of another entity, in each case other than a transaction: 

(A) which results in the Company’s voting securities outstanding immediately before the transaction continuing to
represent (either by remaining outstanding or by being converted into voting securities of the Company or the person that, as a result of the transaction, controls, directly or indirectly, the Company or owns, directly or indirectly, all or
substantially all of the Company’s assets or otherwise succeeds to the business of the Company (the Company or such person, the “Successor Entity”)) directly or indirectly, at least a majority of the combined voting
power of the Successor Entity’s outstanding voting securities immediately after the transaction, and 
 (B) after which
no person or group beneficially owns voting securities representing 50% or more of the combined voting power of the Successor Entity; provided, however, that no person or group shall be treated for purposes of this
Section II(d)(iii)(B) as beneficially owning 50% or more of the combined voting power of the Successor Entity solely as a result of the voting power held in the Company prior to the consummation of the transaction. 

The Administrator shall have full and final authority, which shall be exercised in its discretion, to determine conclusively whether a Change
in Control has occurred pursuant to the above definition, the date of the occurrence of such Change in Control and any incidental matters relating thereto. 

(e) “Code” shall mean the Internal Revenue Code of 1986, as amended from time to time, together with the regulations
and official guidance promulgated thereunder. 
 (f) “Common Stock” shall mean the common stock of the Company and
such other securities of the Company that may be substituted therefor pursuant to Section VIII. 
 (g)
“Company” shall mean Seres Therapeutics, Inc., a Delaware corporation. 
 (h) “Compensation”
of an Eligible Employee shall mean the gross base compensation received by such Eligible Employee as compensation for services to the Company 

  
 2 

 
or any Designated Subsidiary, including overtime payments and excluding sales commissions, incentive compensation, bonuses, expense reimbursements, fringe benefits and other special payments.

 (i) “Designated Subsidiary” shall mean any Subsidiary designated by the Administrator in accordance with
Section XI(c)(ii). 
 (j) “Effective Date” shall mean the day prior to the Public Trading Date. 

(k) “Eligible Employee” shall mean an Employee: (i) who does not, immediately after any rights under this Plan
are granted, own (directly or through attribution) stock possessing 5% or more of the total combined voting power or value of all classes of Common Stock and other stock of the Company, a Parent or a Subsidiary (as determined under
Section 423(b)(3) of the Code); (ii) whose customary employment is for more than twenty hours per week; and (iii) whose customary employment is for more than five months in any calendar year. For purposes of the foregoing clause (i),
the rules of Section 424(d) of the Code with regard to the attribution of stock ownership shall apply in determining the stock ownership of an individual, and stock that an Employee may purchase under outstanding options shall be treated as
stock owned by the Employee; provided, however, that the Administrator may provide in an Offering Document that an Employee shall not be eligible to participate in an Offering Period if: (x) such Employee is a highly compensated
employee within the meaning of Section 423(b)(4)(D) of the Code; and/or (y) such Employee has not met a service requirement designated by the Administrator pursuant to Section 423(b)(4)(A) of the Code (which service requirement may
not exceed two years), and/or (z) such Employee is a citizen or resident of a foreign jurisdiction and the grant of a right to purchase Common Stock under the Plan to such Employee would be prohibited under the laws of such foreign jurisdiction
or the grant of a right to purchase Common Stock under the Plan to such Employee in compliance with the laws of such foreign jurisdiction would cause the Plan to violate the requirements of Section 423 of the Code, as determined by the
Administrator in its sole discretion; provided, further, that any exclusion in clauses (x), (y) or (z) shall be applied in an identical manner under each Offering Period to all Employees, in accordance with Treasury
Regulation Section 1.423-2(e). 
 (l) “Employee” shall mean any officer or other employee (as defined in
accordance with Section 3401(c) of the Code) of the Company or any Designated Subsidiary. “Employee” shall not include any director of the Company or a Designated Subsidiary who does not render services to the Company or a Designated
Subsidiary as an employee within the meaning of Section 3401(c) of the Code. For purposes of the Plan, the employment relationship shall be treated as continuing intact while the individual is on sick leave or other leave of absence approved by
the Company or Designated Subsidiary and meeting the requirements of Treasury Regulation Section 1.421-1(h)(2). Where the period of leave exceeds three (3) months and the individual’s right to reemployment is not guaranteed either by
statute or by contract, the employment relationship shall be deemed to have terminated on the first day immediately following such three (3)-month period. 

(m) “Enrollment Date” shall mean the first Trading Day of each Offering Period. 

  
 3 

 (n) “Exchange Act” shall mean the Securities Exchange Act of 1934, as
amended from time to time. 
 (o) “Fair Market Value” means, as of any date, the value of Common Stock determined as
follows: (i) if the Common Stock is listed on any established stock exchange, its Fair Market Value will be the closing sales price for such Common Stock as quoted on such exchange for such date, or if no sale occurred on such date, the last
day preceding such date during which a sale occurred, as reported in The Wall Street Journal or another source the Administrator deems reliable; (ii) if the Common Stock is not traded on a stock exchange but is quoted on a national market or
other quotation system, the closing sales price on such date, or if no sales occurred on such date, then on the last date preceding such date during which a sale occurred, as reported in The Wall Street Journal or another source the Administrator
deems reliable; or (iii) without an established market for the Common Stock, the Administrator will determine the Fair Market Value in its discretion. 

(p) “Offering Document” shall have the meaning given to such term in Section IV(a). 

(q) “Offering Period” shall have the meaning given to such term in Section IV(a). 

(r) “Parent” shall mean any corporation, other than the Company, in an unbroken chain of corporations ending with the
Company if, at the time of the determination, each of the corporations other than the Company owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the other corporations in such chain. 

(s) “Participant” shall mean any Eligible Employee who has executed a subscription agreement and been granted rights
to purchase Common Stock pursuant to the Plan. 
 (t) “Plan” shall mean this Seres Therapeutics, Inc. 2015 Employee
Stock Purchase Plan, as it may be amended from time to time. 
 (u) “Public Trading Date” shall mean the first date
upon which Common Stock is listed (or approved for listing) upon notice of issuance on any securities exchange or designated (or approved for designation) upon notice of issuance as a national market security on an interdealer quotation system. 

(v) “Purchase Date” shall mean the last Trading Day of each Offering Period. 

(w) “Purchase Price” shall mean the purchase price designated by the Administrator in the applicable Offering Document
(which purchase price shall not be less than 85% of the Fair Market Value of a Share on the Enrollment Date or on the Purchase Date, whichever is lower); provided, however, that, in the event no purchase price is designated by the
Administrator in the applicable Offering Document, the purchase price for the Offering Periods covered by such Offering Document shall be 85% of the Fair Market Value of a Share on the Enrollment Date or on the Purchase Date, whichever is lower;
provided, further, that the Purchase Price may be adjusted by the Administrator pursuant to Section VIII and shall not be less than the par value of a Share. 

  
 4 

 (x) “Securities Act” shall mean the Securities Act of 1933, as amended
from time to time. 
 (y) “Share” shall mean a share of Common Stock. 

(z) “Subsidiary” shall mean any corporation, other than the Company, in an unbroken chain of corporations beginning
with the Company if, at the time of the determination, each of the corporations other than the last corporation in an unbroken chain owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the other
corporations in such chain; provided, however, that a limited liability company or partnership may be treated as a Subsidiary to the extent either (i) such entity is treated as a disregarded entity under Treasury Regulation
Section 301.7701-3(a) by reason of the Company or any other Subsidiary that is a corporation being the sole owner of such entity, or (ii) such entity elects to be classified as a corporation under Treasury Regulation
Section 301.7701-3(a) and such entity would otherwise qualify as a Subsidiary. 
 (aa) “Trading Day” shall mean
a day on which national stock exchanges in the United States are open for trading. 
  

	III.	SHARES SUBJECT TO THE PLAN 

(a) Number of Shares. Subject to Section VIII, the aggregate number of Shares that may be issued pursuant to rights granted under
the Plan shall be 365,000 Shares. In addition to the foregoing, subject to Section VIII, on the first day of each calendar year beginning on January 1, 2016 and ending on and including January 1, 2025, the number of Shares available
for issuance under the Plan shall be increased by that number of Shares equal to the least of (i) 400,000 Shares, (ii) 1% of the Shares outstanding on the final day of the immediately preceding calendar year and (iii) such smaller
number of Shares as determined by the Board. If any right granted under the Plan shall for any reason terminate without having been exercised, the Common Stock not purchased under such right shall again become available for issuance under the Plan.

 (b) Stock Distributed. Any Common Stock distributed pursuant to the Plan may consist, in whole or in part, of authorized and
unissued Common Stock, treasury stock or Common Stock purchased on the open market. 
  

	IV.	OFFERING PERIODS; OFFERING DOCUMENTS 

(a) Offering Periods. The Administrator may from time to time grant or provide for the grant of rights to purchase Common Stock under
the Plan to Eligible Employees during one or more periods (each, an “Offering Period”) selected by the Administrator. The terms and conditions applicable to each Offering Period shall be set forth in an “Offering
Document” adopted by the Administrator, which Offering Document shall be in such form and shall contain such terms and conditions as the Administrator shall deem appropriate and shall be incorporated by reference into and made part of
the Plan and shall be attached hereto as part of the Plan. The provisions of separate Offering Periods under the Plan need not be identical. 

  
 5 

 (b) Offering Documents. Each Offering Document with respect to an Offering Period shall
specify (through incorporation of the provisions of this Plan by reference or otherwise): 
 (i) the length of the Offering Period, which
period shall not exceed twenty-seven months; 
 (ii) the maximum number of Shares that may be purchased by any Eligible Employee during such
Offering Period, which, in the absence of a contrary designation by the Administrator, shall be 25,000 Shares; 
 (iii) such other
provisions as the Administrator determines are appropriate, subject to the Plan. 
  

	V.	ELIGIBILITY AND PARTICIPATION 

 (a)
Eligibility. Any Eligible Employee who shall be employed by the Company or a Designated Subsidiary on a given Enrollment Date for an Offering Period shall be eligible to participate in the Plan during such Offering Period, subject to the
requirements of this Section V and the limitations imposed by Section 423(b) of the Code. 
 (b) Enrollment in Plan. 

(i) Except as otherwise set forth in an Offering Document or determined by the Administrator, an Eligible Employee may become a Participant in
the Plan for an Offering Period by delivering a subscription agreement to the Company by such time prior to the Enrollment Date for such Offering Period (or such other date specified in the Offering Document) designated by the Administrator and in
such form as the Company provides. 
 (ii) Each subscription agreement shall designate a whole percentage of such Eligible Employee’s
Compensation to be withheld by the Company or the Designated Subsidiary employing such Eligible Employee on each payday during the Offering Period as payroll deductions under the Plan. An Eligible Employee may designate any whole percentage of
Compensation that is not less than 1% and not more than the maximum percentage specified by the Administrator in the applicable Offering Document (which percentage shall be 25% in the absence of any such designation) as payroll deductions. The
payroll deductions made for each Participant shall be credited to an account for such Participant under the Plan and shall be deposited with the general funds of the Company. 

(iii) A Participant may increase or decrease the percentage of Compensation designated in his or her subscription agreement, subject to the
limits of this Section V(b), or may suspend his or her payroll deductions, at any time during an Offering Period; provided, however, that the Administrator may limit the number of changes a Participant may make to his or her
payroll deduction elections during each Offering Period in the applicable Offering Document (and in the absence of any specific designation by the Administrator, a Participant shall be allowed one change to his or her payroll deduction elections
during each Offering Period). Any such change or suspension of payroll deductions shall be effective with the first full payroll period following five business days after the Company’s receipt of the new subscription agreement (or such shorter
or longer period as may be specified by the Administrator in the 

  
 6 

 
applicable Offering Document). In the event a Participant suspends his or her payroll deductions, such Participant’s cumulative payroll deductions prior to the suspension shall remain in his
or her account and shall be applied to the purchase of Shares on the next occurring Purchase Date and shall not be paid to such Participant unless he or she withdraws from participation in the Plan pursuant to Section VII. 

(iv) Except as otherwise set forth in an Offering Document or determined by the Administrator, a Participant may participate in the Plan only
by means of payroll deduction and may not make contributions by lump sum payment for any Offering Period. 
 (c) Payroll Deductions.
Except as otherwise provided in the applicable Offering Document, payroll deductions for a Participant shall commence on the first payroll following the Enrollment Date and shall end on the last payroll in the Offering Period to which the
Participant’s authorization is applicable, unless sooner terminated by the Participant as provided in Section VII or suspended by the Participant or the Administrator as provided in Section V(b) and Section V(f), respectively. 

(d) Effect of Enrollment. A Participant’s completion of a subscription agreement will enroll such Participant in the Plan for each
subsequent Offering Period on the terms contained therein until the Participant either submits a new subscription agreement, withdraws from participation under the Plan as provided in Section VII or ceases to be an Eligible Employee. 

(e) Limitation on Purchase of Common Stock. An Eligible Employee may be granted rights under the Plan only if such rights, together
with any other rights granted to such Eligible Employee under “employee stock purchase plans” of the Company, any Parent or any Subsidiary, as specified by Section 423(b)(8) of the Code, do not permit such employee’s rights to
purchase stock of the Company or any Parent or Subsidiary to accrue at a rate that exceeds $25,000 of the fair market value of such stock (determined as of the first day of the Offering Period during which such rights are granted) for each calendar
year in which such rights are outstanding at any time. This limitation shall be applied in accordance with Section 423(b)(8) of the Code. 

(f) Suspension of Payroll Deductions. Notwithstanding the foregoing, to the extent necessary to comply with Section 423(b)(8) of
the Code and Section V(e) or the other limitations set forth in this Plan, a Participant’s payroll deductions may be suspended by the Administrator at any time during an Offering Period. The balance of the amount credited to the account of
each Participant that has not been applied to the purchase of Shares by reason of Section 423(b)(8) of the Code, Section V(e) or the other limitations set forth in this Plan shall be paid to such Participant in one lump sum in cash as soon
as reasonably practicable after the Purchase Date. 
 (g) Foreign Employees. In order to facilitate participation in the Plan, the
Administrator may provide for such special terms applicable to Participants who are citizens or residents of a foreign jurisdiction, or who are employed by a Designated Subsidiary outside of the United States, as the Administrator may consider
necessary or appropriate to accommodate differences in local law, tax policy or custom. Such special terms may not be more favorable than the terms of rights granted under the Plan to Eligible Employees who are residents of the United States.
Moreover, the Administrator may approve such supplements to, or amendments, 

  
 7 

 
restatements or alternative versions of, this Plan as it may consider necessary or appropriate for such purposes without thereby affecting the terms of this Plan as in effect for any other
purpose. No such special terms, supplements, amendments or restatements shall include any provisions that are inconsistent with the terms of this Plan as then in effect unless this Plan could have been amended to eliminate such inconsistency without
further approval by the stockholders of the Company. 
 (h) Leave of Absence. During leaves of absence approved by the Company
meeting the requirements of Treasury Regulation Section 1.421-1(h)(2) under the Code, a Participant may continue participation in the Plan by making cash payments to the Company on his or her normal payday equal to his or her authorized payroll
deduction. 
  

	VI.	GRANT AND EXERCISE OF RIGHTS 

(a) Grant of Rights. On the Enrollment Date of each Offering Period, each Eligible Employee participating in such Offering Period shall
be granted a right to purchase the maximum number of Shares specified under Section IV(b), subject to the limits in Section V(e), and shall have the right to buy, on each Purchase Date during such Offering Period (at the applicable
Purchase Price), such number of whole Shares as is determined by dividing (x) such Participant’s payroll deductions accumulated prior to such Purchase Date and retained in the Participant’s account as of the Purchase Date, by
(y) the applicable Purchase Price (rounded down to the nearest Share). The right shall expire on the last day of the Offering Period. 

(b) Exercise of Rights. On each Purchase Date, each Participant’s accumulated payroll deductions and any other additional payments
specifically provided for in the applicable Offering Document will be applied to the purchase of whole Shares, up to the maximum number of Shares permitted pursuant to the terms of the Plan and the applicable Offering Document, at the Purchase
Price. No fractional Shares shall be issued upon the exercise of rights granted under the Plan, unless the Offering Document specifically provides otherwise. Any cash in lieu of fractional Shares remaining after the purchase of whole Shares upon
exercise of a purchase right will be credited to a Participant’s account and carried forward and applied toward the purchase of whole Shares for the next following Offering Period. Shares issued pursuant to the Plan may be evidenced in such
manner as the Administrator may determine and may be issued in certificated form or issued pursuant to book-entry procedures. 
 (c) Pro
Rata Allocation of Shares. If the Administrator determines that, on a given Purchase Date, the number of Shares with respect to which rights are to be exercised may exceed (i) the number of Shares that were available for issuance under the
Plan on the Enrollment Date of the applicable Offering Period, or (ii) the number of Shares available for issuance under the Plan on such Purchase Date, the Administrator may in its sole discretion provide that the Company shall make a pro rata
allocation of the Shares available for purchase on such Enrollment Date or Purchase Date, as applicable, in as uniform a manner as shall be practicable and as it shall determine in its sole discretion to be equitable among all Participants for whom
rights to purchase Common Stock are to be exercised pursuant to this Section VI on such Purchase Date, and shall either (x) continue all Offering Periods then in effect, or (y) terminate any or all Offering Periods then in effect
pursuant to Section IX. The Company may make pro rata allocation of the Shares available on the Enrollment Date of any applicable Offering Period 

  
 8 

 
pursuant to the preceding sentence, notwithstanding any authorization of additional Shares for issuance under the Plan by the Company’s stockholders subsequent to such Enrollment Date. The
balance of the amount credited to the account of each Participant that has not been applied to the purchase of Shares shall be paid to such Participant in one lump sum in cash as soon as reasonably practicable after the Purchase Date. 

(d) Withholding. At the time a Participant’s rights under the Plan are exercised, in whole or in part, or at the time some or all
of the Common Stock issued under the Plan is disposed of, the Participant must make adequate provision for the Company’s federal, state, or other tax withholding obligations, if any, that arise upon the exercise of the right or the disposition
of the Common Stock. At any time, the Company may, but shall not be obligated to, withhold from the Participant’s compensation the amount necessary for the Company to meet applicable withholding obligations. 

(e) Conditions to Issuance of Common Stock. The Company shall not be required to issue or deliver any certificate or certificates for,
or make any book entries evidencing, Shares purchased upon the exercise of rights under the Plan prior to fulfillment of all of the following conditions: 

(i) The admission of such Shares to listing on all stock exchanges, if any, on which the Common Stock is then listed; and 

(ii) The completion of any registration or other qualification of such Shares under any state or federal law or under the rulings or
regulations of the Securities and Exchange Commission or any other governmental regulatory body, that the Administrator shall, in its absolute discretion, deem necessary or advisable; and 

(iii) The obtaining of any approval or other clearance from any state or federal governmental agency that the Administrator shall, in its
absolute discretion, determine to be necessary or advisable; and 
 (iv) The payment to the Company of all amounts that it is required to
withhold under federal, state or local law upon exercise of the rights, if any; and 
 (v) The lapse of such reasonable period of time
following the exercise of the rights as the Administrator may from time to time establish for reasons of administrative convenience. 
  

	VII.	WITHDRAWAL; CESSATION OF ELIGIBILITY 

(a) Withdrawal. A Participant may withdraw all but not less than all of the payroll deductions credited to his or her account and not
yet used to exercise his or her rights under the Plan at any time by giving written notice to the Company in a form acceptable to the Company no later than one week prior to the end of the Offering Period. All of the Participant’s payroll
deductions credited to his or her account during an Offering Period shall be paid to such Participant as soon as reasonably practicable after receipt of notice of withdrawal and such Participant’s rights for the Offering Period shall be
automatically terminated, and no further payroll deductions for the purchase of Shares shall be made for such Offering Period. If a 

  
 9 

 
Participant withdraws from an Offering Period, payroll deductions shall not resume at the beginning of the next Offering Period unless the Participant delivers to the Company a new subscription
agreement. 
 (b) Future Participation. A Participant’s withdrawal from an Offering Period shall not have any effect upon his or
her eligibility to participate in any similar plan that may hereafter be adopted by the Company or a Designated Subsidiary or in subsequent Offering Periods that commence after the termination of the Offering Period from which the Participant
withdraws. 
 (c) Cessation of Eligibility. Upon a Participant’s ceasing to be an Eligible Employee for any reason, he or she
shall be deemed to have elected to withdraw from the Plan pursuant to this Section VII and the payroll deductions credited to such Participant’s account during the Offering Period shall be paid to such Participant or, in the case of his or
her death, to the person or persons entitled thereto under Section XII(d), as soon as reasonably practicable, and such Participant’s rights for the Offering Period shall be automatically terminated. 

 

	VIII.	ADJUSTMENTS UPON CHANGES IN STOCK 

(a) Changes in Capitalization. Subject to Section VIII(c), in the event that the Administrator determines that any dividend or other
distribution (whether in the form of cash, Common Stock, other securities, or other property), Change in Control, reorganization, merger, amalgamation, consolidation, combination, repurchase, recapitalization, liquidation, dissolution, or sale,
transfer, exchange or other disposition of all or substantially all of the assets of the Company, or sale or exchange of Common Stock or other securities of the Company, issuance of warrants or other rights to purchase Common Stock or other
securities of the Company, or other similar corporate transaction or event, as determined by the Administrator, affects the Common Stock such that an adjustment is determined by the Administrator to be appropriate in order to prevent dilution or
enlargement of the benefits or potential benefits intended by the Company to be made available under the Plan or with respect to any outstanding purchase rights under the Plan, the Administrator shall make equitable adjustments, if any, to reflect
such change with respect to (i) the aggregate number and type of Shares (or other securities or property) that may be issued under the Plan (including, but not limited to, adjustments of the limitations in Section III(a) and the
limitations established in each Offering Document pursuant to Section IV(b) on the maximum number of Shares that may be purchased); (ii) the class(es) and number of shares and price per Share subject to outstanding rights; and
(iii) the Purchase Price with respect to any outstanding rights. 
 (b) Other Adjustments. Subject to Section VIII(c), in
the event of any transaction or event described in Section VIII(a) or any unusual or nonrecurring transactions or events affecting the Company, any affiliate of the Company, or the financial statements of the Company or any affiliate (including
without limitation any Change in Control), or of changes in Applicable Law or accounting principles, the Administrator, in its discretion, and on such terms and conditions as it deems appropriate, is hereby authorized to take any one or more of the
following actions whenever the Administrator determines that such action is appropriate in order to prevent the dilution or enlargement of the benefits or potential benefits intended to be made available under the Plan or with respect to any right
under the Plan, to facilitate such transactions or events or to give effect to such changes in laws, regulations or principles: 
 (i) To
provide for either (x) termination of any outstanding right in exchange for an amount of cash, if any, equal to the amount that would have been obtained upon the exercise of such right had such right been currently exercisable or (y) the
replacement of such outstanding right with other rights or property selected by the Administrator in its sole discretion; 

  
 10 

 (ii) To provide that the outstanding rights under the Plan shall be assumed by the successor or
survivor corporation, or a parent or subsidiary thereof, or shall be substituted for by similar rights covering the stock of the successor or survivor corporation, or a parent or subsidiary thereof, with appropriate adjustments as to the number and
kind of shares and prices; 
 (iii) To make adjustments in the number and type of Shares (or other securities or property) subject to
outstanding rights under the Plan and/or in the terms and conditions of outstanding rights and rights that may be granted in the future; 

(iv) To provide that Participants’ accumulated payroll deductions may be used to purchase Common Stock prior to the next occurring
Purchase Date on such date as the Administrator determines in its sole discretion and the Participants’ rights under the ongoing Offering Period(s) shall be terminated; and 

(v) To provide that all outstanding rights shall terminate without being exercised. 

(c) No Adjustment Under Certain Circumstances. No adjustment or action described in this Section VIII or in any other provision of
the Plan shall be authorized to the extent that such adjustment or action would cause the Plan to fail to satisfy the requirements of Section 423 of the Code. 

(d) No Other Rights. Except as expressly provided in the Plan, no Participant shall have any rights by reason of any subdivision or
consolidation of shares of stock of any class, the payment of any dividend, any increase or decrease in the number of shares of stock of any class or any dissolution, liquidation, merger, or consolidation of the Company or any other corporation.
Except as expressly provided in the Plan or pursuant to action of the Administrator under the Plan, no issuance by the Company of shares of stock of any class, or securities convertible into shares of stock of any class, shall affect, and no
adjustment by reason thereof shall be made with respect to, the number of Shares subject to outstanding rights under the Plan or the Purchase Price with respect to any outstanding rights. 

 

	IX.	AMENDMENT, MODIFICATION AND TERMINATION 

(a) Amendment, Modification and Termination. The Administrator may amend, suspend or terminate the Plan at any time and from time to
time; provided, however, that approval of the Company’s stockholders shall be required to amend the Plan to: (i) increase the aggregate number, or change the type, of shares that may be sold pursuant to rights under the Plan
under Section III(a) (other than an adjustment as provided by Section VIII); (ii) change the corporations or classes of corporations whose employees may be granted rights under the Plan; or (iii) change the Plan in any manner
that would cause the Plan to no longer be an “employee stock purchase plan” within the meaning of Section 423(b) of the Code. 

  
 11 

 (b) Certain Changes to Plan. Without stockholder consent and without regard to whether any
Participant rights may be considered to have been adversely affected, to the extent permitted by Section 423 of the Code, the Administrator shall be entitled to change the Offering Periods, limit the frequency and/or number of changes in the
amount withheld from the Participant’s Compensation during an Offering Period, establish the exchange ratio applicable to amounts withheld from the Participant’s Compensation in a currency other than U.S. dollars, permit payroll
withholding in excess of the amount designated by a Participant in a properly completed subscription agreement in order to adjust for delays or mistakes in the Company’s processing of payroll withholding elections, establish reasonable waiting
and adjustment periods and/or accounting and crediting procedures to ensure that amounts applied toward the purchase of Common Stock for each Participant properly correspond with amounts withheld from the Participant’s Compensation, and
establish such other limitations or procedures as the Administrator determines in its sole discretion to be advisable that are consistent with the Plan. 

(c) Actions In the Event of Unfavorable Financial Accounting Consequences. In the event the Administrator determines that the ongoing
operation of the Plan may result in unfavorable financial accounting consequences, the Administrator may, in its discretion and, to the extent necessary or desirable, modify or amend the Plan to reduce or eliminate such accounting consequence
including, but not limited to: 
 (i) altering the Purchase Price for any Offering Period including an Offering Period underway at the time
of the change in Purchase Price; 
 (ii) shortening any Offering Period so that the Offering Period ends on a new Purchase Date, including
an Offering Period underway at the time of the Administrator action; and 
 (iii) allocating Shares. 

Such modifications or amendments shall not require stockholder approval or the consent of any Participant. 

(d) Payments Upon Termination of Plan. Upon termination of the Plan, the balance in each Participant’s Plan account shall be
refunded as soon as practicable after such termination, without any interest thereon. 
  

	X.	TERM OF PLAN 

 The Plan shall be effective
on the Effective Date. The effectiveness of the Plan shall be subject to approval of the Plan by the stockholders of the Company within twelve months following the date the Plan is first approved by the Board. No right may be granted under the Plan
prior to such stockholder approval. No rights may be granted under the Plan during any period of suspension of the Plan or after termination of the Plan. 
  

	XI.	ADMINISTRATION 

 (a) Administrator. Unless otherwise determined by
the Board, the Administrator of the Plan shall be the Compensation Committee of the Board (or another committee or a 

  
 12 

 
subcommittee of the Board to which the Board delegates administration of the Plan) (such committee, the “Committee”). The Board may at any time vest in the Board any
authority or duties for administration of the Plan. 
 (b) Action by the Administrator. Unless otherwise established by the Board or
in any charter of the Administrator, a majority of the Administrator shall constitute a quorum. The acts of a majority of the members present at any meeting at which a quorum is present and, subject to Applicable Law and the Bylaws of the Company,
acts approved in writing by a majority of the Administrator in lieu of a meeting, shall be deemed the acts of the Administrator. Each member of the Administrator is entitled to, in good faith, rely or act upon any report or other information
furnished to that member by any officer or other Employee, the Company’s independent certified public accountants, or any executive compensation consultant or other professional retained by the Company to assist in the administration of the
Plan. 
 (c) Authority of Administrator. The Administrator shall have the power, subject to, and within the limitations of, the
express provisions of the Plan: 
 (i) To determine when and how rights to purchase Common Stock shall be granted and the provisions of each
offering of such rights (which need not be identical). 
 (ii) To designate from time to time which Subsidiaries of the Company shall be
Designated Subsidiaries, which designation may be made without the approval of the stockholders of the Company. 
 (iii) To construe and
interpret the Plan and rights granted under it, and to establish, amend and revoke rules and regulations for its administration. The Administrator, in the exercise of this power, may correct any defect, omission or inconsistency in the Plan, in a
manner and to the extent it shall deem necessary or expedient to make the Plan fully effective. 
 (iv) To amend the Plan as provided in
Section IX. 
 (v) Generally, to exercise such powers and to perform such acts as the Administrator deems necessary or expedient to
promote the best interests of the Company and its Subsidiaries and to carry out the intent that the Plan be treated as an “employee stock purchase plan” within the meaning of Section 423 of the Code. 

(d) Decisions Binding. The Administrator’s interpretation of the Plan, any rights granted pursuant to the Plan, any subscription
agreement and all decisions and determinations by the Administrator with respect to the Plan are final, binding, and conclusive on all parties. 
  

	XII.	MISCELLANEOUS 

 (a) Restriction upon Assignment. A right granted
under the Plan shall not be transferable other than by will or the applicable laws of descent and distribution, and is exercisable during the Participant’s lifetime only by the Participant. Except as provided in Section XII(d) hereof, a
right under the Plan may not be exercised to any extent except by the Participant. The Company shall not recognize and shall be under no duty to recognize any assignment or alienation of the Participant’s interest in the Plan, the
Participant’s rights under the Plan or any rights thereunder. 

  
 13 

 (b) Rights as a Stockholder. With respect to Shares subject to a right granted under the
Plan, a Participant shall not be deemed to be a stockholder of the Company, and the Participant shall not have any of the rights or privileges of a stockholder, until such Shares have been issued to the Participant or his or her nominee following
exercise of the Participant’s rights under the Plan. No adjustments shall be made for dividends (ordinary or extraordinary, whether in cash securities, or other property) or distribution or other rights for which the record date occurs prior to
the date of such issuance, except as otherwise expressly provided herein or as determined by the Administrator. 
 (c) Interest. No
interest shall accrue on the payroll deductions or contributions of a Participant under the Plan. 
 (d) Designation of Beneficiary.

 (i) A Participant may, in the manner determined by the Administrator, file a written designation of a beneficiary who is to receive any
Shares and cash, if any, from the Participant’s account under the Plan in the event of such Participant’s death subsequent to a Purchase Date on which the Participant’s rights are exercised but prior to delivery to such Participant of
such Shares and cash. In addition, a Participant may file a written designation of a beneficiary who is to receive any cash from the Participant’s account under the Plan in the event of such Participant’s death prior to exercise of the
Participant’s rights under the Plan. If the Participant is married and resides in a community property state, a designation of a person other than the Participant’s spouse as his or her beneficiary shall not be effective without the prior
written consent of the Participant’s spouse. 
 (ii) Such designation of beneficiary may be changed by the Participant at any time by
written notice to the Company. In the event of the death of a Participant and in the absence of a beneficiary validly designated under the Plan who is living at the time of such Participant’s death, the Company shall deliver such Shares and/or
cash to the executor or administrator of the estate of the Participant, or if no such executor or administrator has been appointed (to the knowledge of the Company), the Company, in its discretion, may deliver such Shares and/or cash to the spouse
or to any one or more dependents or relatives of the Participant, or if no spouse, dependent or relative is known to the Company, then to such other person as the Company may designate. 

(e) Notices. All notices or other communications by a Participant to the Company under or in connection with the Plan shall be deemed
to have been duly given when received in the form specified by the Company at the location, or by the person, designated by the Company for the receipt thereof. 

(f) Equal Rights and Privileges. Subject to Section V(g), all Eligible Employees will have equal rights and privileges under this
Plan so that this Plan qualifies as an “employee stock purchase plan” within the meaning of Section 423 of the Code. Subject to Section V(g), any provision of this Plan that is inconsistent with Section 423 of the Code will,
without further act or amendment by the Company, the Board or the Administrator, be reformed to comply with the equal rights and privileges requirement of Section 423 of the Code. 

  
 14 

 (g) Use of Funds. All payroll deductions received or held by the Company under the Plan
may be used by the Company for any corporate purpose, and the Company shall not be obligated to segregate such payroll deductions. 
 (h)
Reports. Statements of account shall be given to participating Eligible Employees at least annually, which statements shall set forth the amounts of payroll deductions, the Purchase Price, the number of Shares purchased and the remaining cash
balance, if any. 
 (i) No Employment Rights. Nothing in the Plan shall be construed to give any person (including any Eligible
Employee or Participant) the right to remain in the employ of the Company or any Parent or Subsidiary or affect the right of the Company or any Parent or Subsidiary to terminate the employment of any person (including any Eligible Employee or
Participant) at any time, with or without cause. 
 (j) Notice of Disposition of Shares. Each Participant shall give prompt notice to
the Company of any disposition or other transfer of any Shares purchased upon exercise of a right under the Plan if such disposition or transfer is made: (i) within two years from the Enrollment Date of the Offering Period in which the Shares
were purchased or (ii) within one year after the Purchase Date on which such Shares were purchased. Such notice shall specify the date of such disposition or other transfer and the amount realized, in cash, other property, assumption of
indebtedness or other consideration, by the Participant in such disposition or other transfer. 
 (k) Governing Law. The Plan and any
agreements hereunder shall be administered, interpreted and enforced under the internal laws of the State of Delaware without regard to conflicts of laws thereof or of any other jurisdiction. 

(l) Electronic Forms. To the extent permitted by Applicable Law and in the discretion of the Administrator, an Eligible Employee may
submit any form or notice as set forth herein by means of an electronic form approved by the Administrator. Before the commencement of an Offering Period, the Administrator shall prescribe the time limits within which any such electronic form shall
be submitted to the Administrator with respect to such Offering Period in order to be a valid election. 
 * * * * * 

  
 15

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