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 *
HENDERSON JOHN T
   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
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
280 EAST GRAND AVENUE		 3. Date of Earliest Transaction (Month/Day/Year)
01/02/2013
(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               1,500 D  
Common Stock               500 I by Spouse

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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
Non-Qualified Stock Option (right to buy) $ 0.6702 01/02/2013   A   130,558   02/02/2013(1) 01/02/2023 Common Stock 130,558 $ 0.2681 (2) 130,558 D  
Non-Qualified Stock Option (right to buy) $ 0.91             06/22/2012(3) 05/22/2022 Common Stock 25,000   25,000 D  
Non-Qualified Stock Option (right to buy) $ 0.98             02/03/2012(4) 01/03/2022 Common Stock 51,020   51,020 D  
Non-Qualified Stock Option (right to buy) $ 1.44             06/18/2011(5) 05/18/2021 Common Stock 20,000   20,000 D  
Non-Qualified Stock Option (right to buy) $ 1.75             05/01/2009(6) 04/01/2019 Common Stock 21,428   21,428 D  
Non-Qualified Stock Option (right to buy) $ 1.85             06/21/2009(7) 05/21/2019 Common Stock 15,000   15,000 D  
Non-Qualified Stock Option (right to buy) $ 1.95             03/19/2009(8) 02/19/2019 Common Stock 30,000   30,000 D  
Non-Qualified Stock Option (right to buy) $ 2.16             02/03/2011(9) 01/03/2021 Common Stock 23,148   23,148 D  
Non-Qualified Stock Option (right to buy) $ 2.81             06/20/2010(10) 05/20/2020 Common Stock 20,000   20,000 D  
Non-Qualified Stock Option (right to buy) $ 3.11             02/04/2010(11) 01/04/2020 Common Stock 16,077   16,077 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
HENDERSON JOHN T
280 EAST GRAND AVENUE
SOUTH SAN FRANCISCO, CA 94080		   X      

Signatures

 By: Sharon A. Barbari For: John T. Henderson   01/04/2013
**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) This option shall vest and become exercisable as to 130,558 shares divided into equal monthly installments such that the option shall be 100% vested on January 2, 2014.
(2) This option was issued to the reporting person pursuant to the Cytokinetics 2004 Equity Incentive Plan in lieu of an annual retainer of $35,000.
(3) This option shall vest and become exercisable as to 25,000 shares divided into equal monthly installments such that the option shall be 100% vested on May 22, 2013.
(4) This option shall vest and become exercisable as to 51,020 shares divided into equal monthly installments such that the option shall be 100% vested on January 3, 2013.
(5) This option shall vest and become exercisable as to 20,000 shares divided into equal monthly installments such that the option shall be 100% vested on May 18, 2012.
(6) This option shall vest and become exercisable as to 21,428 shares divided into equal monthly installments such that the option shall be 100% vested on January 1, 2010.
(7) This option shall vest and become exercisable as to 15,000 shares divided into equal monthly installments such that the option shall be 100% vested on May 21, 2010.
(8) This option shall vest and become exercisable as to 833 shares on 03/19/09 and the balance of 29,167 divided into equal monthly installments thereafter such that the option shall be 100% vested on 02/19/12.
(9) This option shall vest and become exercisable as to 23,148 shares divided into equal monthly installments such that the option shall be 100% vested on January 3, 2012.
(10) This option shall vest and become exercisable as to 20,000 shares divided into equal monthly installments such that the option shall be 100% vested on May 20, 2011.
(11) This option shall vest and become exercisable as to 16,077 shares divided into equal monthly installments such that the option shall be 100% vested on January 4, 2011.

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