Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Nestle Health Science US Holdings, Inc.
2. Date of Event Requiring Statement (Month/Day/Year)
06/25/2015
3. Issuer Name and Ticker or Trading Symbol
Seres Therapeutics, Inc. [MCRB]
(Last)
(First)
(Middle)
C/O NESTLE USA, INC., 383 MAIN AVE., 5TH FLOOR
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

NORWALK, CT 06851
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 1,944,444
I
See Footnote (1)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Series D Convertible Preferred Stock   (2)   (2) Common Stock 3,611,111 $ (2) I See Footnote (1)

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Nestle Health Science US Holdings, Inc.
C/O NESTLE USA, INC.
383 MAIN AVE., 5TH FLOOR
NORWALK, CT 06851
    X    
NESTLE SA
AVE NESTLE 55, CH-1800
VEVEY, V8 
    X    
NIMCO US, Inc.
383 MAIN AVE., 5TH FLOOR
NORWALK, CT 06851
    X    

Signatures

NESTLE HEALTH SCIENCE US HOLDINGS, INC., By: /s/ James Pepin, Name: James Pepin, Title: President 06/25/2015
**Signature of Reporting Person Date

NIMCO US, INC., By: /s/ Yun Au, Name: Yun Au, Title: Chief Legal Officer 06/25/2015
**Signature of Reporting Person Date

NESTLE S.A., By: /s/ David P. Frick, Name: David P. Frick, Title: Secretary to the Board of Directors 06/25/2015
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Held by Nestle Health Science US Holdings, Inc. Nestle Health Science US Holdings, Inc. is a wholly owned subsidiary of NIMCO US, Inc., which is a wholly owned subsidiary of Nestle S.A., a publically traded company. Each of these entities may be deemed to share voting and investment power with respect to all shares held by Nestle Health Science US Holdings, Inc. Each of the filing persons disclaims beneficial ownership of such shares except to the extent of its pecuniary interest therein.
(2) Each class of Series D Convertible Preferred Stock is convertible into Common Stock on a one-for-one basis and has no expiration date. Each share of Series D Convertible Preferred Stock will convert into Common Stock upon the listing of the issuer's securities on The NASDAQ Global Select Market.

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