FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 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 *
von Emster Kurt
   2. Issuer Name and Ticker or Trading Symbol
CymaBay Therapeutics, Inc. [CBAY] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
C/O CYMABAY THERAPEUTICS, INC., 7999 GATEWAY BLVD, SUITE 130		 3. Date of Earliest Transaction (Month/Day/Year)
08/13/2015
(Street)

NEWARK, CA 94560		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 08/13/2015   P   31,359 A $ 2.6838 (1) 31,359 D  
Common stock 08/14/2015   P   58,641 A $ 2.6997 (2) 90,000 D  
Common Stock               1,600,000 (3) I See footnote (4)
Common Stock               17,326 I By The Konrad Hans von Emster III and Elizabeth F. von Emster Revocable Trust dated January 18, 2005

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
von Emster Kurt
C/O CYMABAY THERAPEUTICS, INC.
7999 GATEWAY BLVD, SUITE 130
NEWARK, CA 94560		   X      

Signatures

 /s/ Sujal Shah, by power of attorney   08/17/2015
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(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) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $2.675 to $2.69, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range.
(2) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $2.68 to $2.70, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range.
(3) Consists of (i) 533,333 shares held by Abingworth Bioventures VI, LP ("ABV VI"), and (ii) 1,066,667 shares held by Abingworth Bioequities Master Fund Limited ("ABE," and collectively with ABV VI, the "Abingworth Funds").
(4) Abingworth LLP ("ALLP") provides advisory services to the Abingworth Funds. Kurt von Emster ("Emster") is a member of ALLP. Emster may be deemed the indirect beneficial owner of the shares through his indirect interest in the Abingworth Funds. Emster disclaims beneficial ownership of the shares except to the extent, if any, of his pecuniary interest therein. This report shall not be deemed an admission that ALLP, the Abingworth Funds, Emster or any other person is the beneficial owner of the securities reported herein for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

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