<SEC-DOCUMENT>0001193125-23-062117.txt : 20230307
<SEC-HEADER>0001193125-23-062117.hdr.sgml : 20230307
<ACCEPTANCE-DATETIME>20230307074238
ACCESSION NUMBER:		0001193125-23-062117
CONFORMED SUBMISSION TYPE:	S-8
PUBLIC DOCUMENT COUNT:		5
FILED AS OF DATE:		20230307
DATE AS OF CHANGE:		20230307
EFFECTIVENESS DATE:		20230307

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Seres Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001609809
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				274326290
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		S-8
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-270319
		FILM NUMBER:		23711052

	BUSINESS ADDRESS:	
		STREET 1:		200 SIDNEY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		617 945 9626

	MAIL ADDRESS:	
		STREET 1:		200 SIDNEY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Seres Health, Inc.
		DATE OF NAME CHANGE:	20140603
</SEC-HEADER>
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<TYPE>S-8
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<FILENAME>d465067ds8.htm
<DESCRIPTION>S-8
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>As filed with the Securities and Exchange Commission on March&nbsp;7, 2023 </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Registration <FONT STYLE="white-space:nowrap">No.&nbsp;333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT> </B></P>
<P STYLE="font-size:4pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:4pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>Washington, D.C. 20549 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>FORM <FONT
STYLE="white-space:nowrap">S-8</FONT> </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>REGISTRATION STATEMENT </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>UNDER </I></B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>THE
SECURITIES ACT OF 1933 </I></B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:24pt; font-family:Times New Roman" ALIGN="center"><B>SERES THERAPEUTICS, INC. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(Exact Name of Registrant as Specified in Its Charter) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" ALIGN="center"><B>Delaware</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B><FONT STYLE="white-space:nowrap">27-4326290</FONT></B></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(State or other jurisdiction of</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>incorporation or organization)</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(I.R.S. Employer</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Identification No.)</B></P></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>200 Sidney Street &#150; 4<SUP STYLE="font-size:75%; vertical-align:top">th</SUP> Floor </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Cambridge, MA 02139 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Address of Principal Executive Offices) (Zip Code) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Seres Therapeutics, Inc. 2015 Incentive Award Plan </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Seres Therapeutics, Inc. 2015 Employee Stock Purchase Plan </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Full Title of the Plan) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Eric D. Shaff. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>President and Chief Executive Officer </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Seres Therapeutics, Inc. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>200 Sidney Street &#150; 4<SUP STYLE="font-size:75%; vertical-align:top">th</SUP> Floor </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Cambridge, MA 02139 </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Name
and Address of Agent for Service) </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(617) <FONT STYLE="white-space:nowrap">945-9626</FONT> </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Telephone Number, including Area Code, of Agent for Service) </B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><I>Copies to: </I></B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Peter N. Handrinos, Esq. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Latham&nbsp;&amp; Watkins LLP </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>200 Clarendon Street </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Boston, MA 02116 </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(617) <FONT
STYLE="white-space:nowrap">948-6060</FONT> </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a <FONT
STYLE="white-space:nowrap">non-accelerated</FONT> filer, a smaller reporting company or an emerging growth company. See the definitions of &#147;large accelerated filer,&#148; &#147;accelerated filer,&#148; &#147;smaller reporting company,&#148; and
&#147;emerging growth company&#148; in Rule <FONT STYLE="white-space:nowrap">12b-2</FONT> of the Exchange Act. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


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<TD WIDTH="2%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">Large&nbsp;accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Accelerated filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9746;</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"><FONT STYLE="white-space:nowrap">Non-accelerated</FONT> filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Smaller&nbsp;reporting&nbsp;company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Emerging&nbsp;growth&nbsp;company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period
for complying with new or revised financial accounting standards provided pursuant to Section&nbsp;7(a)(2)(B) of the Securities Act.&nbsp;&nbsp;&#9744; </P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>EXPLANATORY NOTE </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">This Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> is being filed for the purpose of registering an additional 400,000 shares of
the common stock of Seres Therapeutics, Inc. (the &#147;<B><I>Registrant</I></B>&#148;) to be issued pursuant to the Seres Therapeutics, Inc. 2015 Employee Stock Purchase Plan (the &#147;<B><I>ESPP</I></B>&#148;) and an additional 5,008,890 shares
of the Registrant&#146;s common stock to be issued pursuant to the Seres Therapeutics, Inc. 2015 Incentive Award Plan (the &#147;<B><I>Incentive Plan</I></B>,&#148; and together with the ESPP, the &#147;<B><I>Plans</I></B>&#148;). A Registration
Statement of the Registrant on Form <FONT STYLE="white-space:nowrap">S-8</FONT> relating to the Plans is effective. </P> <P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>INCORPORATION BY
REFERENCE OF CONTENTS OF </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>REGISTRATION STATEMENTS ON FORM <FONT STYLE="white-space:nowrap">S-8</FONT> </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Except as set forth below, the contents of the Registration Statements on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (File Nos. <A HREF="http://www.sec.gov/Archives/edgar/data/1609809/000119312515236648/d948161ds8.htm">
<FONT STYLE="white-space:nowrap">333-205253</FONT></A>, <A HREF="http://www.sec.gov/Archives/edgar/data/1609809/000119312516503517/d288825ds8.htm"><FONT STYLE="white-space:nowrap">333-210171</FONT></A>, <A HREF="http://www.sec.gov/Archives/edgar/data/1609809/000119312518074569/d526660ds8.htm">
<FONT STYLE="white-space:nowrap">333-223514</FONT></A>, <A HREF="http://www.sec.gov/Archives/edgar/data/1609809/000119312519065218/d698213ds8.htm"><FONT STYLE="white-space:nowrap">333-230092</FONT></A>, <A HREF="http://www.sec.gov/Archives/edgar/data/1609809/000119312520058927/d865737ds8.htm">
<FONT STYLE="white-space:nowrap">333-236824</FONT></A>, <A HREF="http://www.sec.gov/Archives/edgar/data/1609809/000119312521064827/d24654ds8.htm"><FONT STYLE="white-space:nowrap">333-253776</FONT></A>, and <A HREF="http://www.sec.gov/Archives/edgar/data/1609809/000119312522060244/d683320ds8.htm">
<FONT STYLE="white-space:nowrap">333-263134</FONT></A>), including any amendments thereto, filed with the Securities and Exchange Commission, relating to the Plans, are incorporated by reference herein. </P>
<P STYLE="font-size:18pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="11%" VALIGN="top" ALIGN="left"><B>Item&nbsp;6.</B></TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left"><B>Indemnification of Directors and Officers. </B></P></TD></TR></TABLE>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Subsection (a)&nbsp;of Section&nbsp;145 of the General Corporation Law of the State of Delaware (the &#147;<B><I>DGCL</I></B>&#148;), empowers a corporation to
indemnify any person who was or is a party or who is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right
of the corporation) by reason of the fact that the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise, against expenses (including attorneys&#146; fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with such action, suit or
proceeding if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe
the person&#146;s conduct was unlawful. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Subsection (b)&nbsp;of Section&nbsp;145 empowers a corporation to indemnify any person who was or is a party or
is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that the person acted in any of the capacities set forth above,
against expenses (including attorneys&#146; fees) actually and reasonably incurred by the person in connection with the defense or settlement of such action or suit if the person acted in good faith and in a manner the person reasonably believed to
be in or not opposed to the best interests of the corporation, except that no indemnification shall be made in respect of any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to
the extent that the Court of Chancery or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, such person is fairly and
reasonably entitled to indemnity for such expenses which the Court of Chancery or such other court shall deem proper. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Section&nbsp;145 further provides
that to the extent a director or officer of a corporation has been successful on the merits or otherwise in the defense of any action, suit or proceeding referred to in subsections (a)&nbsp;and (b) of Section&nbsp;145, or in defense of any claim,
issue or matter therein, such person shall be indemnified against expenses (including attorneys&#146; fees) actually and reasonably incurred by such person in connection therewith; that indemnification provided for by Section&nbsp;145 shall not be
deemed exclusive of any other rights to which the indemnified party may be entitled; and the indemnification provided for by Section&nbsp;145 shall, unless otherwise provided when authorized or ratified, continue as to a person who has ceased to be
a director, officer, employee or agent and shall inure to the benefit of such person&#146;s heirs, executors and administrators. Section&nbsp;145 also empowers the corporation to purchase and maintain insurance on behalf of any person who is or was
a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against any
liability asserted against such person and incurred by such person in any such capacity, or arising out of his status as such, whether or not the corporation would have the power to indemnify such person against such liabilities under
Section&nbsp;145. </P>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Section&nbsp;102(b)(7) of the DGCL provides that a corporation&#146;s certificate of incorporation may
contain a provision eliminating or limiting the personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, provided that such provision shall not eliminate or limit the
liability of a director (i)&nbsp;for any breach of the director&#146;s duty of loyalty to the corporation or its stockholders, (ii)&nbsp;for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law,
(iii)&nbsp;under Section&nbsp;174 of the DGCL, or (iv)&nbsp;for any transaction from which the director derived an improper personal benefit. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The
Registrant&#146;s amended and restated bylaws (the &#147;<B><I>Bylaws</I></B>&#148;) provide that it will indemnify each person who was or is a party or threatened to be made a party to any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the Registrant) by reason of the fact that he or she is or was, or has agreed to become, a director or officer, or, while a director or
officer, is or was serving, or has agreed to serve, at the Registrant&#146;s request as a director, officer, partner, employee or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or other enterprise
(including, without limitation, any employee benefit plan) (all such persons being referred to hereafter as an &#147;<B><I>Indemnitee</I></B>&#148;), or by reason of any action alleged to have been taken or omitted in such capacity, against all
expenses (including, without limitation, attorneys&#146; fees), liabilities, losses, judgments, fines (including, without limitation, excise taxes and penalties arising under the Employee Retirement Income Security Act of 1974), and amounts paid in
settlement actually and reasonably incurred by or on behalf of Indemnitee in connection with such action, suit or proceeding and any appeal therefrom, if such Indemnitee acted in good faith and in a manner which Indemnitee reasonably believed to be
in, or not opposed to, the Registrant&#146;s best interests, and, with respect to any criminal action or proceeding, had no reasonable cause to believe Indemnitee&#146;s conduct was unlawful. The termination of any action, suitor proceeding by
judgment, order, settlement, conviction or upon a plea of nolo contendere or its equivalent, shall not, of itself, create a presumption that Indemnitee did not act in good faith and in a manner which Indemnitee reasonably believed to be in, or not
opposed to, the best interests of the Registrant, and, with respect to any criminal action or proceeding, had reasonable cause to believe that Indemnitee&#146;s conduct was unlawful. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Bylaws provide that the Registrant will indemnify any Indemnitee who was or is a party to or threatened to be made a party to any threatened, pending or
completed action or suit by or in the right of the Registrant to procure a judgment in the Registrant&#146;s favor by reason of the fact that Indemnitee is or was, or has agreed to become, a director or officer, or, while a director or officer, is
or was serving, or has agreed to serve, at the Registrant&#146;s request as a director, officer, partner, employee or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or other enterprise (including,
without limitation, any employee benefit plan), or by reason of any action alleged to have been taken or omitted in such capacity, against all expenses (including, without limitation, attorneys&#146; fees) actually and reasonably incurred by or on
behalf of Indemnitee in connection with such action, suit or proceeding and any appeal therefrom, if Indemnitee acted in good faith and in a manner which Indemnitee reasonably believed to be in, or not opposed to, the best interests of the
Registrant, except that no indemnification shall be made in respect of any claim, issue or matter as to which Indemnitee shall have been adjudged to be liable to the Registrant, unless, and only to the extent, that the Court of Chancery of Delaware
or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of such liability but in view of all the circumstances of the case, Indemnitee is fairly and reasonably entitled to indemnity for
such expenses (including, without limitation, attorneys&#146; fees) which the Court of Chancery of Delaware or such other court shall deem proper. Notwithstanding the foregoing, to the extent that an Indemnitee has been successful, on the merits or
otherwise, in defense of any action, suit or proceeding, or in defense of any claim, issue or matter therein, or on appeal from any such action, suit or proceeding, Indemnitee shall be indemnified to the fullest extent permitted by law against all
expenses (including, without limitation, attorneys&#146; fees) actually and reasonably incurred by or on behalf of Indemnitee in connection therewith. Expenses must be advanced to an Indemnitee under certain circumstances. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Registrant has entered into indemnification agreements with each of its directors and executive officers in which the Registrant has agreed to indemnify,
defend and hold harmless, and also advance expenses as incurred, to the fullest extent permitted under applicable law, from damage arising from the fact that such person is or was an officer or director of the Registrant or its subsidiaries. </P>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always">
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The indemnification rights set forth above shall not be exclusive of any other right which an Indemnitee may
have or hereafter acquire under any statute, the Registrant&#146;s restated certificate of incorporation, Bylaws, any agreement, any vote of stockholders or disinterested directors or otherwise. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Registrant expects to maintain standard policies of insurance that provide coverage to (1)&nbsp;the Registrant&#146;s directors and officers against loss
rising from claims made by reason of breach of duty or other wrongful act and (2)&nbsp;to the Registrant with respect to indemnification payments that we may make to such directors and officers. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Registrant has purchased and intends to maintain insurance on behalf of the Company and any person who is or was a director or officer against any loss
arising from any claim asserted against him or her and incurred by him or her in that capacity, subject to certain exclusions and limits of the amount of coverage. </P> <P STYLE="font-size:18pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="11%" VALIGN="top" ALIGN="left"><B>Item&nbsp;8.</B></TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left"><B>Exhibits. </B></P></TD></TR></TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD></TD>

<TD VALIGN="bottom" WIDTH="4%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP ALIGN="center"><B>Number</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; border-bottom:1.00pt solid #000000; display:table-cell; font-size:8pt; font-family:Times New Roman; " ALIGN="center"><B>Description</B></P></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1609809/000119312515242845/d48188dex31.htm">Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.1 to the Registrant&#146;s Current Report on Form
<FONT STYLE="white-space:nowrap">8-K</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-37456)</FONT> filed on July&nbsp;1, 2015) </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1609809/000119312515242845/d48188dex31.htm">Amended and Restated <FONT STYLE="white-space:nowrap">By-Laws</FONT> of the Registrant (incorporated by reference to Exhibit 3.1 to the Registrant&#146;s
 Current Report on Form <FONT STYLE="white-space:nowrap">8-K</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-37456)</FONT> filed on December&nbsp;7, 2020) </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;5.1+</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d465067dex51.htm">Opinion of Latham&nbsp;&amp; Watkins LLP, counsel to the Registrant </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.1+</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d465067dex231.htm">Consent of PricewaterhouseCoopers LLP, Independent Registered Public Accounting Firm </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.2+</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d465067dex51.htm">Consent of Latham&nbsp;&amp; Watkins LLP (included in Exhibit 5.1) </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>24.1+</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="#sig">Power of attorney (included on signature pages below)</A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1609809/000095017023006374/mcrb-ex10_1.htm">Seres Therapeutics, Inc. 2015 Incentive Award Plan (incorporated by reference to Exhibit 10.1 to the Registrant&#146;s Annual Report on Form
<FONT STYLE="white-space:nowrap">10-K</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;001-37456)</FONT> filed on March&nbsp;7, 2023) </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1609809/000119312515202059/d816354dex103.htm">Seres Therapeutics, Inc. 2015 Employee Stock Purchase Plan (incorporated by reference to Exhibit 10.3 to the Registrant&#146;s Registration Statement
 on Form <FONT STYLE="white-space:nowrap">S-1</FONT> (Reg. <FONT STYLE="white-space:nowrap">No.&nbsp;333-204484)</FONT> filed on May&nbsp;27, 2015) </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>107+</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d465067dexfilingfees.htm">Filing Fee Table </A></TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="2%" VALIGN="top" ALIGN="left">+</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Filed herewith </P></TD></TR></TABLE>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always">
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SIGNATURES </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form <FONT STYLE="white-space:nowrap">S-8</FONT> and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Cambridge, Commonwealth of
Massachusetts, on this 7<SUP STYLE="font-size:75%; vertical-align:top">th</SUP> day of March, 2023. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="7%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3"><B>SERES THERAPEUTICS, INC.</B></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Eric D. Shaff</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Eric D. Shaff</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">President and Chief Executive Officer</TD></TR>
</TABLE></DIV> <P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><A NAME="sig"></A>POWER OF ATTORNEY </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Eric D. Shaff and David Arkowitz, or either of them,
as his or her true and lawful <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorneys-in-fact</FONT></FONT> and agents, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead,
in any and all capacities, to file and sign any and all amendments, including post-effective amendments, to this registration statement, with the Securities and Exchange Commission, granting unto said <FONT STYLE="white-space:nowrap"><FONT
STYLE="white-space:nowrap">attorneys-in-fact</FONT></FONT> and agents, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith as fully to all intents and purposes as he or
she might or could do in person, hereby ratifying and confirming all that said <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorneys-in-fact</FONT></FONT> and agents, or their substitute or substitutes may lawfully do or cause
to be done by virtue hereof. This power of attorney shall be governed by and construed with the laws of the State of Delaware and applicable federal securities laws. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the
dates indicated. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="43%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="38%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="17%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" ALIGN="center"><B>SIGNATURE</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>TITLE</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>DATE</B></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Eric D. Shaff</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP>President, Chief Executive Officer, Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center">March&nbsp;7, 2023</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">Eric D. Shaff</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP>(<I>principal executive officer</I>)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ROWSPAN="2"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ David Arkowitz</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">David Arkowitz</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Executive Vice President, Chief Financial</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Officer, and Head of Business Development</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">March&nbsp;7, 2023</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(<I>principal accounting officer and principal</I></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><I>financial officer</I>)</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Stephen Berenson</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP>Chairman of the Board</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center">March&nbsp;7, 2023</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">Stephen Berenson</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Dennis Ausiello</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP>Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center">March&nbsp;7, 2023</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">Dennis Ausiello, M.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Gr&eacute;gory Behar</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP>Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center">March&nbsp;7, 2023</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">Gr&eacute;gory Behar</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Paul R. Biondi</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP>Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center">March&nbsp;7, 2023</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">Paul R. Biondi</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Willard H. Dere</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP>Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center">March&nbsp;7, 2023</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">Willard H. Dere, M.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR></TABLE>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always">
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">

<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="43%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="38%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="17%"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>

<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Claire M. Fraser</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP>Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center">March&nbsp;7, 2023</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">Claire M. Fraser, Ph.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Kurt C. Graves</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP>Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center">March&nbsp;7, 2023</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">Kurt C. Graves</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Richard N. Kender</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP>Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center">March&nbsp;7, 2023</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">Richard N. Kender</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">/s/ Meryl S. Zausner</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP>Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center">March&nbsp;7, 2023</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman" ALIGN="center">Meryl S. Zausner</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
</TABLE>
</DIV></Center>

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</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>2
<FILENAME>d465067dex51.htm
<DESCRIPTION>EX-5.1
<TEXT>
<HTML><HEAD>
<TITLE>EX-5.1</TITLE>
</HEAD>
 <BODY BGCOLOR="WHITE">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Exhibit 5.1 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD WIDTH="57%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="28%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="13%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="3">200 Clarendon Street</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="3">Boston, Massachusetts 02116</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="3">Tel: +1.617.948.6000 Fax: +1.617.948.6001</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">www.lw.com</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="3">FIRM / AFFILIATE OFFICES</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">


<IMG SRC="g465067g0302050731582.jpg" ALT="LOGO">
</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Austin</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Milan</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Beijing</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Munich</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Boston</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">New York</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Brussels</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Orange&nbsp;County</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Century City</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Paris</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Chicago</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Riyadh</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Dubai</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">San Diego</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">D&uuml;sseldorf</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">San&nbsp;Francisco</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Frankfurt</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Seoul</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Hamburg</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Shanghai</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Hong Kong</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Silicon Valley</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Houston</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Singapore</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">March&nbsp;7, 2023</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">London</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Tel Aviv</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Los Angeles</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Tokyo</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Madrid</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Washington,&nbsp;D.C.</TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Seres Therapeutics, Inc. </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">200
Sidney Street &#150; 4<SUP STYLE="font-size:75%; vertical-align:top">th</SUP> Floor </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Cambridge, MA 02139 </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="5%" VALIGN="top" ALIGN="left">Re:</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8;</FONT> 5,408,890 shares of Seres
Therapeutics, Inc. Common Stock, $0.001 par value per share </P></TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">To the addressee set forth above: </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">We have acted as special counsel to Seres Therapeutics, Inc., a Delaware corporation (the &#147;<B><I>Company</I></B>&#148;), in connection
with the preparation and filing by the Company with the Securities and Exchange Commission (the &#147;<B><I>Commission</I></B>&#148;) of a registration statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (the &#147;<B><I>Registration
Statement</I></B>&#148;) under the Securities Act of 1933, as amended (the &#147;<B><I>Act</I></B>&#148;), relating to the issuance by the Company of up to an aggregate of 5,408,890 shares of common stock of the Company, $0.001 par value per share
(the &#147;<B><I>Shares</I></B>&#148;), issuable under the Seres Therapeutics, Inc. 2015 Incentive Award Plan (the &#147;<B><I>2015 Plan</I></B>&#148;) and the Seres Therapeutics, Inc. 2015 Employee Stock Purchase Plan (together with the 2015 Plan,
the &#147;<B><I>Plans</I></B>&#148;). This opinion is being furnished in connection with the requirements of Item 601(b)(5) of Regulation <FONT STYLE="white-space:nowrap">S-K</FONT> under the Act, and no opinion is expressed herein as to any matter
pertaining to the contents of the Registration Statement or the prospectus forming a part thereof, other than as expressly stated herein with respect to the issuance of the Shares. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">As such counsel, we have examined such matters of fact and questions of law as we have considered appropriate for purposes of this letter.
With your consent, we have relied upon certificates and other assurances of officers of the Company and others as to factual matters without having independently verified such factual matters. We are opining herein as to the General Corporation Law
of the State of Delaware (the &#147;<B><I>DGCL</I></B>&#148;), and we express no opinion with respect to any other laws. </P>
</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always">
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">

 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>March 7, 2023 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Page 2 </B></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt;margin-bottom:0pt">


<IMG SRC="g465067g0302050731582.jpg" ALT="LOGO">
 </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:0pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Subject to the foregoing and the other matters set forth herein, it is our opinion that, as
of the date hereof, when the Shares shall have been duly registered on the books of the transfer agent and registrar therefor in the name or on behalf of the purchasers, and have been issued by the Company for legal consideration in excess of par
value in the circumstances contemplated by the Plans, assuming in each case that the individual grants or awards under the Plans are duly authorized by all necessary corporate action and duly granted or awarded and exercised in accordance with the
requirements of law and the Plans (and the agreements and awards duly adopted thereunder and in accordance therewith), the issue and sale of the Shares will have been duly authorized by all necessary corporate action of the Company, and the Shares
will be validly issued, fully paid and nonassessable. In rendering the foregoing opinion, we have assumed that the Company will comply with all applicable notice requirements regarding uncertificated shares provided in the DGCL. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">This opinion is for your benefit in connection with the Registration Statement and may be relied upon by you and by persons entitled to rely
upon it pursuant to the applicable provisions of the Act. We consent to your filing this opinion as an exhibit to the Registration Statement. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is
required under Section&nbsp;7 of the Act or the rules and regulations of the Commission thereunder. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="100%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Sincerely,</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">/s/ Latham&nbsp;&amp; Watkins LLP</TD></TR>
</TABLE></DIV>
</DIV></Center>

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</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-23.1
<SEQUENCE>3
<FILENAME>d465067dex231.htm
<DESCRIPTION>EX-23.1
<TEXT>
<HTML><HEAD>
<TITLE>EX-23.1</TITLE>
</HEAD>
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Exhibit 23.1 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">We hereby consent to the incorporation by reference in this Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> of Seres Therapeutics,
Inc. of our report dated March&nbsp;7, 2023 relating to the financial statements and the effectiveness of internal control over financial reporting, which appears in Seres Therapeutics, Inc.&#146;s Annual Report on Form <FONT
STYLE="white-space:nowrap">10-K</FONT> for the year ended December 31, 2022. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">/s/PricewaterhouseCoopers LLP </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Boston, Massachusetts </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">March&nbsp;7, 2023 </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">1 </P>

</DIV></Center>

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</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-FILING FEES
<SEQUENCE>4
<FILENAME>d465067dexfilingfees.htm
<DESCRIPTION>EX-FILING FEES
<TEXT>
<HTML><HEAD>
<TITLE>EX-FILING FEES</TITLE>
</HEAD>
 <BODY BGCOLOR="WHITE">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Exhibit 107 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>CALCULATION OF FILING FEE TABLE </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>FORM <FONT STYLE="white-space:nowrap">S-8</FONT> </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">(Form Type) </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SERES
THERAPEUTICS, INC. </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">(Exact Name of Registrant as Specified in its Charter) </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><U>Table I: Newly Registered Securities </U></B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="92%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>

<TD WIDTH="10%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="9%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="14%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="11%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="11%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="7%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="14%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="13%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="9%"></TD>

<TD VALIGN="bottom"></TD>
<TD></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="1" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; padding-left:8pt">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-RIGHT:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:7pt">
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;BORDER-LEFT:1px solid #000000; padding-left:8pt"><B>Plan</B></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;"><B>Security&nbsp;Type</B></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:7pt; font-family:Times New Roman" ALIGN="center"><B>Security</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:7pt; font-family:Times New Roman" ALIGN="center"><B>Class</B></P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:7pt; font-family:Times New Roman" ALIGN="center"><B>Title</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:7pt; font-family:Times New Roman" ALIGN="center"><B>Fee</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:7pt; font-family:Times New Roman" ALIGN="center"><B>Calculation<BR>Rule</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;"><B>Amount<BR>Registered<SUP STYLE="font-size:75%; vertical-align:top">(1)</SUP></B></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;"><B>Proposed<BR>Maximum<BR>Offering<BR>Price Per<BR>Unit</B></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:7pt; font-family:Times New Roman" ALIGN="center"><B>Maximum</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:7pt; font-family:Times New Roman" ALIGN="center"><B>Aggregate</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:7pt; font-family:Times New Roman" ALIGN="center"><B>Offering</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:7pt; font-family:Times New Roman" ALIGN="center"><B>Price</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:7pt; font-family:Times New Roman" ALIGN="center"><B>Fee</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:7pt; font-family:Times New Roman" ALIGN="center"><B>Rate</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;BORDER-RIGHT:1px solid #000000"><B>Amount of<BR>Registration<BR>Fee</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="1" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; padding-left:8pt">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-RIGHT:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;BORDER-LEFT:1px solid #000000; padding-left:8pt">2015 Incentive Award Plan</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">Equity</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">Common Stock, par&nbsp;value&nbsp;$0.001 per share</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">Rule&nbsp;457(c)&nbsp;<BR>and 457(h)</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">5,008,890<SUP STYLE="font-size:75%; vertical-align:top">(2)</SUP>&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">$5.01<SUP STYLE="font-size:75%; vertical-align:top">(4)</SUP>&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">$25,094,538.90&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">$110.20 per million&nbsp;dollars&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;BORDER-RIGHT:1px solid #000000">$2,765.42&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="1" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; padding-left:8pt">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-RIGHT:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;BORDER-LEFT:1px solid #000000; padding-left:8pt">2015 Employee Stock Purchase Plan</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">Equity</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">Common Stock, par value $0.001 per share</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">Rule 457(c)<BR>and 457(h)</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">400,000<SUP STYLE="font-size:75%; vertical-align:top">(3)</SUP></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">$5.01<SUP STYLE="font-size:75%; vertical-align:top">(4)</SUP></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">$2,004,000.00</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;">$110.20 per million&nbsp;dollars</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center" STYLE="padding-bottom:1pt ;BORDER-RIGHT:1px solid #000000">$&nbsp;&nbsp;&nbsp;220.85</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="1" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; padding-left:8pt">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="8" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-RIGHT:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; padding-left:8pt">&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="7" ALIGN="center" STYLE="padding-bottom:1pt ;"><B>Total Offering Amounts</B></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;">$27,098,538.90</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;BORDER-RIGHT:1px solid #000000">$2,986.27</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="1" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; padding-left:8pt">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="8" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-RIGHT:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; padding-left:8pt">&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="7" ALIGN="center" STYLE="padding-bottom:1pt ;"><B>Total Fee Offsets</B></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;BORDER-RIGHT:1px solid #000000">$&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&#151;&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="1" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; padding-left:8pt">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="8" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-RIGHT:1px solid #000000">&nbsp;</TD>
<TD HEIGHT="1" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="7" ALIGN="center" STYLE="padding-bottom:1pt ;BORDER-BOTTOM:1px solid #000000"><B>Net Fee Due</B></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="padding-bottom:1pt ;BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">$2,986.27</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(1)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">In accordance with Rule 416(a) under the Securities Act of 1933, as amended (&#147;<B><I>Securities
Act</I></B>&#148;), this registration statement shall be deemed to cover any additional securities that may from time to time be offered or issued under the Seres Therapeutics, Inc. 2015 Incentive Award Plan (the &#147;<B><I>Incentive
Plan</I></B>&#148;) and the Seres Therapeutics, Inc. 2015 Employee Stock Purchase Plan (the &#147;<B><I>ESPP</I></B>&#148;) to prevent dilution resulting from stock splits, stock dividends or similar transactions. In addition, pursuant to Rule
416(c) under the Securities Act, this registration statement also covers an indeterminate amount of interests to be offered or sold pursuant to the Incentive Plan and the ESPP. </P></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(2)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Consists of 5,008,890 shares of Common Stock that may become issuable under the Incentive Plan pursuant to its
terms. </P></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(3)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Consists of 400,000 shares of Common Stock that may become issuable under the ESPP pursuant to its terms.
</P></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(4)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Estimated solely for the purpose of calculating the registration fee pursuant to Rules 457(c) and 457(h) of the
Securities Act of 1933, as amended, and based upon the average of the high and low prices of the Common Stock as reported on the Nasdaq Global Select Market on February&nbsp;28, 2023. </P></TD></TR></TABLE>
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end
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
