<SEC-DOCUMENT>0000899243-17-002128.txt : 20170127
<SEC-HEADER>0000899243-17-002128.hdr.sgml : 20170127
<ACCEPTANCE-DATETIME>20170127175632
ACCESSION NUMBER:		0000899243-17-002128
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20170126
FILED AS OF DATE:		20170127
DATE AS OF CHANGE:		20170127

ISSUER:		

	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

	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

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Aunins John G.
		CENTRAL INDEX KEY:			0001643756

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37465
		FILM NUMBER:		17554961

	MAIL ADDRESS:	
		STREET 1:		C/O SERES HEALTH, INC.
		STREET 2:		161 FIRST STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02472
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-01-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001609809</issuerCik>
        <issuerName>Seres Therapeutics, Inc.</issuerName>
        <issuerTradingSymbol>MCRB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001643756</rptOwnerCik>
            <rptOwnerName>Aunins John G.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SERES THERAPEUTICS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>200 SIDNEY STREET</rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02139</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Technology Officer &amp; EVP</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>9.89</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2017-01-26</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>50000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2027-01-25</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>50000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>50000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2017-01-26</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>25000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>25000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>25000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The option will vest as to 25% of the shares on January 26, 2018.  The remainder of the shares will vest in 12 equal quarterly installments thereafter.</footnote>
        <footnote id="F2">Each restricted stock unit represents a contingent right to receive one share of Issuer common stock.</footnote>
        <footnote id="F3">These restricted stock units vest as to 20% on January 26, 2018, 30% on January 26, 2019 and 50% on January 26, 2020.</footnote>
    </footnotes>

    <remarks>Exhibit List
    Exhibit 24 - Power of Attorney</remarks>

    <ownerSignature>
        <signatureName>/s/ Thomas J. DesRosier, Attorney-in-fact</signatureName>
        <signatureDate>2017-01-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>attachment1.htm
<DESCRIPTION>EX-24 DOCUMENT
<TEXT>
<HTML>
<HEAD>
</HEAD>
<BODY>
<PRE>
                                                                      Exhibit 24
                                POWER OF ATTORNEY

        KNOW ALL BY THESE PRESENTS, as of this 30th day of August, 2016, that
the undersigned hereby constitutes and appoints the Chief Executive Officer of
Seres Therapeutics, Inc. (the "Company"), who is currently Roger J. Pomerantz,
the Chief Financial Officer of the Company who is currently Eric D. Shaff, and
the Chief Legal Officer of the Company who is currently Thomas J. DesRosier, or
any or each of them signing singly, and with full power of substitution, the
undersigned's true and lawful attorney-in-fact to:

     (1)  prepare, execute in the undersigned's name and on the undersigned's
          behalf, and submit to the U.S. Securities and Exchange Commission (the
          "SEC") a Form ID, including amendments thereto, and any other
          documents necessary or appropriate to obtain codes and passwords
          enabling the undersigned to make electronic filings with the SEC of
          reports required by Section 16(a) of the Securities Exchange Act of
          1934 (the "Exchange Act") or any rule or regulation of the SEC;

     (2)  execute for and on behalf of the undersigned, in the undersigned's
          capacity as an officer and/or director of the Company, Forms 3, 4, and
          5 in accordance with Section 16(a) of the Exchange Act and the rules
          thereunder;

     (3)  do and perform any and all acts for and on behalf of the undersigned
          which may be necessary or desirable to complete and execute any such
          Form 3, 4, or 5, complete and execute any amendment or amendments
          thereto, and timely file such form with the SEC and any stock exchange
          or similar authority; and

     (4)  take any other action of any type whatsoever in connection with the
          foregoing which, in the opinion of such attorney-in-fact, may be of
          benefit to, in the best interest of, or legally required by, the
          undersigned, it being understood that the documents executed by such
          attorney-in-fact on behalf of the undersigned pursuant to this Power
          of Attorney shall be in such form and shall contain such terms and
          conditions as such attorney-in-fact may approve in such
          attorney-in-fact's discretion.

     The undersigned hereby grants to each such attorney-in-fact full power and
authority to do and perform any and every act and thing whatsoever requisite,
necessary, or proper to be done in the exercise of any of the rights and powers
herein granted, as fully to all intents and purposes as the undersigned might or
could do if personally present, with full power of substitution and/or
revocation, hereby ratifying and confirming all that such attorney-in-fact, or
such attorney-in-fact's substitute or substitutes, shall lawfully do or cause to
be done by virtue of this power of attorney and the rights and powers herein
granted. The undersigned acknowledges that the foregoing attorneys-in-fact, in
serving in such capacity at the request of the undersigned, are not assuming,
nor is the Company assuming, any of the undersigned's responsibilities to comply
with Section 16 of the Exchange Act.

        This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms 3, 4, and 5 with respect to the
undersigned's holdings of and transactions in securities issued by the Company,
unless earlier revoked by the undersigned in a signed writing delivered to the
foregoing attorneys-in-fact.

        IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to
be executed as of the date first written above.


/s/ John Aunins
--------------------
Signature


John Aunins, Ph.D.
---------------------
Printed Name

</PRE>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
