UNITED STATES

OMB APPROVAL

SECURITIES AND EXCHANGE COMMISSION

OMB Number:
3235-0145

Washington, D.C. 20549

Expires:
December 31, 2005

Estimated average burden hours per response. . 11

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Rule 13d-1(b)

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Rule 13d-1(c)

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Rule 13d-1(d)

CUSIP No.  24823Q107

1.

Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only)
Paul G. Allen

2.

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)

o

(b)

o

3.

SEC Use Only

4.

Citizenship or Place of Organization
United States of America

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5.

Sole Voting Power
-0- shares

6.

Shared Voting Power 
2,314,700 shares (1)

7.

Sole Dispositive Power 
-0- shares

8.

Shared Dispositive Power
2,314,700 shares (1)

9.

Aggregate Amount Beneficially Owned by Each Reporting Person
2,314,700 shares(1)

10.

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o

11.

Percent of Class Represented by Amount in Row (9)
8.1%(2)

12.

Type of Reporting Person (See Instructions)
IN

1.

Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only)
Vulcan Ventures Incorporated

2.

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)

o

(b)

o

3.

SEC Use Only

4.

Citizenship or Place of Organization
State of Washington

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5.

Sole Voting Power
-0- shares

6.

Shared Voting Power 
2,314,700 shares (1)

7.

Sole Dispositive Power 
-0- shares

8.

Shared Dispositive Power
2,314,700 shares (1)

9.

Aggregate Amount Beneficially Owned by Each Reporting Person
2,314,700 shares (2)

10.

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o

11.

Percent of Class Represented by Amount in Row (9)
8.1%(2)

12.

Type of Reporting Person (See Instructions)
CO

Item 1.

(a)

Name of Issuer
Cytokinetics, Inc.

(b)

Address of Issuer’s Principal Executive Offices
280 East Grand Ave.
South San Francisco, CA  94080

Item 2.

(a)

Name of Person Filing
Paul G. Allen and Vulcan Ventures Incorporated

(b)

Address of Principal Business Office or, if none, Residence
The address for both filing persons is as follows:

505 Union Station, Suite 900
Seattle, Washington  98104

(c)

Citizenship
Paul G. Allen is a citizen of the United States of America. 
Vulcan Ventures Incorporated is a corporation organized under the laws of the State of Washington.

(d)

Title of Class of Securities
Common Stock

(e)

CUSIP Number
23282W100

Item 3.

If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:

(a)

o

Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).

(b)

o

Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).

(c)

o

Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).

(d)

o

Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C 80a-8).

(e)

o

An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);

(f)

o

An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);

(g)

o

A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);

(h)

o

A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i)

o

A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

(j)

o

Group, in accordance with §240.13d-1(b)(1)(ii)(J).

Not applicable.

Item 4.

Ownership

Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.

(a)

Amount beneficially owned:   
2,314,700 shares (1)

(b)

Percent of class:   
8.1% (2)

(c)

Number of shares as to which the person has:

(i)

Sole power to vote or to direct the vote   
-0- shares

(ii)

Shared power to vote or to direct the vote    
2,314,700 shares (1)

(iii)

Sole power to dispose or to direct the disposition of   
-0- shares

(iv)

Shared power to dispose or to direct the disposition of   
2,314,700 shares (1)

Item 5.

Ownership of Five Percent or Less of a Class

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following   o.

Item 6.

Ownership of More than Five Percent on Behalf of Another Person

Not applicable.

Item 7.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person

Not applicable.

Item 8.

Identification and Classification of Members of the Group

Not applicable.

Item 9.

Notice of Dissolution of Group

Not applicable.

Item 10.

Certification

Not applicable.

VULCAN VENTURES INCORPORATED

May     , 2005

By:

/s/ W. Lance Conn 

Name and Title:

W. Lance Conn, Executive Vice President

May     , 2005

/s/ W. Lance Conn

Paul G. Allen

*By:

/s/ W. Lance Conn

Name:

/s/ W. Lance Conn 

Attorney-in Fact for Paul G. Allen

Exhibit

Description

99.1

Joint Filing Agreement