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 *
Blum Robert I
   2. Issuer Name and Ticker or Trading Symbol
CYTOKINETICS INC [CYTK] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
President & CEO
(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   175,000 A (1) 193,416 D  
Common Stock 09/04/2012   F(2)   64,105 D $ 0.7598 129,311 D  
Common Stock               12,500 I by Trust 1 (3)
Common Stock               12,500 I by Trust 2 (4)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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     175,000   (5)   (5) Common Stock 175,000 $ 0 175,000 D  
Incentive Stock Option (right to buy) $ 0.58             01/14/2000(6) 11/14/2010 Common Stock 12   12 D  
Incentive Stock Option (right to buy) $ 1.05             04/05/2012(7) 03/05/2022 Common Stock 92,212   92,212 D  
Incentive Stock Option (right to buy) $ 1.2             07/10/2002(8) 07/10/2012 Common Stock 18,833   18,833 D  
Incentive Stock Option (right to buy) $ 1.2             05/21/2003(9) 05/21/2013 Common Stock 32,500   32,500 D  
Incentive Stock Option (right to buy) $ 1.57             03/31/2011(10) 02/28/2021 Common Stock 62,459   62,459 D  
Incentive Stock Option (right to buy) $ 1.85             03/26/2009(11) 02/26/2019 Common Stock 50,333   50,333 D  
Incentive Stock Option (right to buy) $ 2             12/18/2003(12) 12/18/2013 Common Stock 27,500   27,500 D  
Incentive Stock Option (right to buy) $ 3.08             03/24/2010(13) 02/24/2020 Common Stock 36,834   36,834 D  
Incentive Stock Option (right to buy) $ 3.37             03/29/2008(14) 02/28/2018 Common Stock 8,334   8,334 D  
Incentive Stock Option (right to buy) $ 6.59             04/11/2005(15) 04/11/2015 Common Stock 45,000   45,000 D  
Incentive Stock Option (right to buy) $ 6.81             04/01/2007(16) 03/14/2017 Common Stock 22,806   22,806 D  
Incentive Stock Option (right to buy) $ 7.15             03/01/2006(17) 03/01/2016 Common Stock 28,494   28,494 D  
Non-Qualified Stock Option (right to buy) $ 1.05             04/05/2012(7) 03/05/2022 Common Stock 357,788   357,788 D  
Non-Qualified Stock Option (right to buy) $ 1.2             07/10/2002(8) 07/10/2012 Common Stock 12,264   12,264 D  
Non-Qualified Stock Option (right to buy) $ 1.57             03/31/2011(10) 02/28/2021 Common Stock 437,541   437,541 D  
Non-Qualified Stock Option (right to buy) $ 1.85             03/26/2009(11) 02/26/2019 Common Stock 224,667   224,667 D  
Non-Qualified Stock Option (right to buy) $ 2             12/18/2003(12) 12/18/2013 Common Stock 48,692   48,692 D  
Non-Qualified Stock Option (right to buy) $ 3.08             03/24/2010(13) 02/24/2020 Common Stock 233,166   233,166 D  
Non-Qualified Stock Option (right to buy) $ 3.37             03/29/2008(14) 02/28/2018 Common Stock 191,666   191,666 D  
Non-Qualified Stock Option (right to buy) $ 6.81             04/01/2007(16) 03/14/2017 Common Stock 227,194   227,194 D  
Non-Qualified Stock Option (right to buy) $ 7.15             03/01/2006(17) 03/01/2016 Common Stock 71,506   71,506 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Blum Robert I
280 EAST GRAND AVENUE
SOUTH SAN FRANCISCO, CA 94080		   X     President & CEO  

Signatures

 Robert I. Blum   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) Shares held by The Bridget Blum 2003 Irrevocable Trust.
(4) Shares held by The Brittany Blum 2003 Irrevocable Trust.
(5) 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.
(6) This option is immediately exercisable upon grant and shall vest as to 25,000 shares on 11/14/00 and the balance of 87,500 divided into equal monthly installments thereafter such that the option shall be 100% vested on 11/14/05.
(7) When the ISO and NQ dated 03/05/2012 are combined for a total grant of 450,000 shares, the option shall vest and become exercisable as to 9,375 shares on 04/05/2012 and the balance of 440,625 divided into equal monthly installments thereafter such that the option shall be 100% vested on 03/05/2016.
(8) When the ISO and NQ dated 07/10/02 are combined for a total grant of 150,000 shares, the option is immediately exercisable upon grant and shall vest as to 2,500 shares on 04/15/02 and the balance of 147,500 divided into equal monthly installments thereafter such that the option shall be 100% vested on 03/15/07.
(9) This option is immediately exercisable upon grant and shall vest as to 781 shares on 04/01/03 and the balance of 36,719 divided into equal monthly installments thereafter such that the option shall be 100% vested on 03/01/07.
(10) When the ISO and NQ dated 02/28/2011 are combined for a total grant of 500,000 shares, the option shall vest and become exercisable as to 10,416 shares on 03/31/2011 and the balance of 489,584 divided into equal monthly installments thereafter such that the option shall be 100% vested on 02/28/2015.
(11) When the ISO and NQ dated 02/26/2009 are combined for a total grant of 275,000 shares, the option shall vest and become exercisable as to 5,729 shares on 03/26/09 and the balance of 269,271 divided into equal monthly installments thereafter such that the option shall be 100% vested on 02/26/13.
(12) When the ISO and NQ dated 12/18/03 are combined for a total grant of 141,925 shares, the option is immediately exercisable upon grant and shall vest as to 2,365 shares on 01/18/04 and the balance of 139,560 divided into equal monthly installments thereafter such that the option shall be 100% vested on 12/18/08.
(13) When the ISO and NQ dated 02/24/2010 are combined for a total grant of 270,000 shares, the option shall vest and become exercisable as to 5,625 shares on 03/24/2010 and the balance of 264,375 divided into equal monthly installments thereafter such that the option shall be 100% vested on 02/24/2014.
(14) When the ISO and NQ dated 02/29/2008 are combined for a total grant of 200,000 shares, the option shall vest and become exercisable as to 4,166 shares on 03/29/08 and the balance of 195,834 divided into equal monthly installments thereafter such that the option shall be 100% vested on 02/29/12.
(15) This option shall vest and become exercisable as to 45,000 shares divided into equal monthly installments such that the option shall be 100% vested on 03/01/2009.
(16) When the ISO and NQ dated 03/14/2007 are combined for a total grant of 250,000 shares, the option shall vest and become exercisable as to 5,208 shares on 04/01/07 and the balance of 244,792 divided into equal monthly installments thereafter such that the option shall be 100% vested on 03/01/11.
(17) When the ISO and NQ dated 03/01/2006 are combined for a total grant of 100,000 shares, the option shall vest and become exercisable as to 100,000 shares divided into equal monthly installments such that the option shall be 100% vested on 03/01/2010.

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