Ownership Submission
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, 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 *
WOLFF ANDREW A
   2. Issuer Name and Ticker or Trading Symbol
CYTOKINETICS INC [CYTK] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP Clinical R&D, CMO
(Last)
(First)
(Middle)
280 EAST GRAND AVENUE		 3. Date of Earliest Transaction (Month/Day/Year)
09/04/2012
(Street)

SOUTH SAN FRANCISCO, CA 94080		 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 09/04/2012   M   87,500 A (1) 98,750 D  
Common Stock 09/04/2012   F(2)   32,052 D $ 0.7598 66,698 D  

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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
Restricted Stock Units (1) 09/04/2012   M     87,500   (3)   (3) Common Stock 87,500 $ 0 87,500 D  
Incentive Stock Option (right to buy) $ 1.05             04/05/2012(4) 03/05/2022 Common Stock 58,665   58,665 D  
Incentive Stock Option (right to buy) $ 1.57             03/31/2011(5) 02/28/2021 Common Stock 58,336   58,336 D  
Incentive Stock Option (right to buy) $ 1.85             03/26/2009(6) 02/26/2019 Common Stock 37,917   37,917 D  
Incentive Stock Option (right to buy) $ 3.08             03/24/2010(7) 02/24/2020 Common Stock 42,084   42,084 D  
Incentive Stock Option (right to buy) $ 3.37             03/29/2008(8) 02/28/2018 Common Stock 27,935   27,935 D  
Incentive Stock Option (right to buy) $ 6.59             04/11/2005(9) 04/11/2015 Common Stock 781   781 D  
Incentive Stock Option (right to buy) $ 6.81             04/01/2007(10) 03/14/2017 Common Stock 14,185   14,185 D  
Incentive Stock Option (right to buy) $ 7.15             03/01/2006(11) 03/01/2016 Common Stock 17,019   17,019 D  
Incentive Stock Option (right to buy) $ 9.91             09/20/2005(12) 10/20/2014 Common Stock 40,360   40,360 D  
Non-Qualified Stock Option (right to buy) $ 1.05             04/05/2012(4) 03/05/2022 Common Stock 116,335   116,335 D  
Non-Qualified Stock Option (right to buy) $ 1.57             03/31/2011(5) 02/28/2021 Common Stock 141,664   141,664 D  
Non-Qualified Stock Option (right to buy) $ 1.85             03/26/2009(6) 02/26/2019 Common Stock 92,083   92,083 D  
Non-Qualified Stock Option (right to buy) $ 3.08             03/24/2010(7) 02/24/2020 Common Stock 92,916   92,916 D  
Non-Qualified Stock Option (right to buy) $ 3.37             03/29/2008(8) 02/28/2018 Common Stock 97,065   97,065 D  
Non-Qualified Stock Option (right to buy) $ 6.59             04/11/2005(9) 04/11/2015 Common Stock 11,719   11,719 D  
Non-Qualified Stock Option (right to buy) $ 6.81             04/01/2007(10) 03/14/2017 Common Stock 40,815   40,815 D  
Non-Qualified Stock Option (right to buy) $ 7.15             03/01/2006(11) 03/01/2016 Common Stock 42,981   42,981 D  
Non-Qualified Stock Option (right to buy) $ 9.91             09/20/2005(12) 10/20/2014 Common Stock 69,640   69,640 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
WOLFF ANDREW A
280 EAST GRAND AVENUE
SOUTH SAN FRANCISCO, CA 94080		       SVP Clinical R&D, CMO  

Signatures

 Andrew A. Wolff, M.D.   09/05/2012
**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) Each restricted stock unit represents a contingent right to receive one share of CYTK common stock at a purchase price of $0.001 per share which is the current par value of the common stock.
(2) Shares withheld by Issuer to cover taxes associated with settlement of Restricted Stock Units
(3) The restricted stock units vest in two equal annual installments. Vested shares will be delivered to the reporting person on 9/4/2012 and 9/3/2013.
(4) When the ISO and NQ dated 03/05/2012 are combined for a total grant of 175,000 shares, the option shall vest and become exercisable as to 3,645 shares on 04/05/2012 and the balance of 171,355 divided into equal monthly installments thereafter such that the option shall be 100% vested on 03/05/2016.
(5) When the ISO and NQ dated 02/28/2011 are combined for a total grant of 200,000 shares, the option shall vest and become exercisable as to 4,166 shares on 03/31/2011 and the balance of 195,834 divided into equal monthly installments thereafter such that the option shall be 100% vested on 02/28/2015.
(6) When the ISO and NQ dated 02/26/2009 are combined for a total grant of 130,000 shares, the option shall vest and become exercisable as to 2,708 shares on 03/26/09 and the balance of 127,292 divided into equal monthly installments thereafter such that the option shall be 100% vested on 02/26/13.
(7) When the ISO and NQ dated 02/24/2010 are combined for a total grant of 135,000 shares, the option shall vest and become exercisable as to 2,812 shares on 03/24/2010 and the balance of 132,188 divided into equal monthly installments thereafter such that the option shall be 100% vested on 02/24/2014.
(8) When the ISO and NQ dated 02/29/2008 are combined for a total grant of 125,000 shares, the option shall vest and become exercisable as to 2,604 shares on 03/29/08 and the balance of 122,396 divided into equal monthly installments thereafter such that the option shall be 100% vested on 02/29/12.
(9) When the ISO and NQ dated 04/11/05 are combined for a total grant of 12,500 shares, the option shall vest and become exercisable as to 12,500 shares divided into equal monthly installments such that the option shall be 100% vested on 03/01/2009.
(10) When the ISO and NQ dated 03/14/2007 are combined for a total grant of 55,000 shares, the option shall vest and become exercisable as to 1,146 shares on 04/01/07 and the balance of 53,854 divided into equal monthly installments thereafter such that the option shall be 100% vested on 03/01/11.
(11) When the ISO and NQ dated 03/01/2006 are combined for a total grant of 60,000 shares, the option shall vest and become exercisable as to 60,000 shares divided into equal monthly installments such that the option shall be 100% vested on 03/01/2010.
(12) When the ISO and NQ dated 10/20/04 are combined for a total grant of 110,000 shares, the option shall vest and become exercisable as to 27,500 shares on 09/20/05 and the balance of 82,500 divided into equal monthly installments thereafter such that the option shall be 100% vested on 09/20/08.

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