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 * DOW STEPHEN M   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) C/O SEVIN ROSEN FUNDS, 13455 NOEL ROAD, SUITE 1670 3. Date of Earliest Transaction (Month/Day/Year) 08/17/2007 (Street) DALLAS, TX 75240 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 08/17/2007   P   20,000 A $ 5.071 145,000 I (1) See Footnote Common Stock               3,164,002 I (2) See Footnote

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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
DOW STEPHEN M C/O SEVIN ROSEN FUNDS 13455 NOEL ROAD, SUITE 1670 DALLAS, TX 75240	X

Signatures

John V. Jaggers, As Attorney-In-Fact		08/20/2007
**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)	Shares are held by the Dow Family trust (the "Dow Trust"). Mr. Dow is a trustee and beneficiary of the Dow Trust.
(2)	Total common shares of 3,164,002 represents 1,615,715 of such common shares held by Sevin Rosen Fund VI L.P. ("SRFVI"), 127,235 of such common shares held by Sevin Rosen VI Affiliates Fund L.P. ("SRVI AFF"), 625,950 of such common shares held by Sevin Rosen Fund VII L.P. ("SRFVII"), 24,050 of such common shares held by Sevin Rosen VII Affiliates Fund L.P. ("SRVII AFF"), 755,631 of such common shares held by Sevin Rosen Fund VIII L.P. ("SRFVIII") and 15,421 of such common shares held by Sevin Rosen VIII Affiliates Fund L.P. ("SRVIII AFF"). Dow is a general partner of the general partner of SRFVI, SRVI AFF, SRFVII, SRVII AFF, SRFVIII and SRVIII AFF. Dow disclaims beneficial ownership of these shares except to the extent of his proportionate partnership interest in these shares.

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