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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO.)*
Onyx Pharmaceuticals, Inc.
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(NAME OF ISSUER)
Common Stock, $0.001 Par Value
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(TITLE OF CLASS OF SECURITIES)
Common Stock: 683399-10-9
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(CUSIP NUMBER)
*THE REMAINDER OF THIS COVER PAGE SHALL BE FILLED OUT FOR A REPORTING
PERSON'S INITIAL FILING ON THIS FORM WITH RESPECT TO THE SUBJECT CLASS OF
SECURITIES, AND FOR ANY SUBSEQUENT AMENDMENT CONTAINING INFORMATION WHICH WOULD
ALTER DISCLOSURES PROVIDED IN A PRIOR COVER PAGE.
THE INFORMATION REQUIRED IN THE REMAINDER OF THIS COVER PAGE SHALL NOT BE
DEEMED TO BE "FILED" FOR THE PURPOSE OF SECTION 18 OF THE SECURITIES EXCHANGE
ACT OF 1934 ("ACT") OR OTHERWISE SUBJECT TO THE LIABILITIES OF THAT SECTION OF
THE ACT BUT SHALL BE SUBJECT TO ALL OTHER PROVISIONS OF THE ACT (HOWEVER, SEE
THE NOTES).
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CUSIP No 683399-10-9
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1) Names of Reporting Persons S.S. or I.R.S. Identification Nos. of Above
Persons
Chiron Corporation, I.R.S. Identification No. 94-2754624
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2) Check the Appropriate Box if a Member of a Group (See Instructions)
(a) / /
(b) / /
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3) SEC Use Only
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4) Citizenship or Place of Organization
Delaware
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-----------------------------------------------------------------
Number (5) Sole Voting Power
of Shares
Bene- 1,400,756 shares of Common Stock
ficially -----------------------------------------------------------------
Owned by
Each (6) Shared Voting Power
Reporting
Person 0
With -----------------------------------------------------------------
(7) Sole Dispositive Power
1,400,756 shares of Common Stock
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(8) Shared Dispositive Power
0
9) Aggregate Amount Beneficially Owned by Each Reporting Person
1,400,756 shares of Common Stock
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10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
Instructions)
/ /
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11) Percent of Class Represented by Amount in Row 9
Common Stock: 14.7%
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12) Type of Reporting Person (See Instructions)
CO
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ITEM 1(a) NAME OF ISSUER:
Onyx Pharmaceuticals, Inc.
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ITEM 1(b) ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:
3031 Research Drive, Richmond, CA 94806
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ITEM 2(a) NAME OF PERSON FILING:
Chiron Corporation
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ITEM 2(b) ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE:
4560 Horton Street, Emeryville, CA 94608
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ITEM 2(c) CITIZENSHIP:
Delaware
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ITEM 2(d) TITLE OF CLASS OF SECURITIES:
Common Stock, $0.001 Par Value
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ITEM 2(e) CUSIP NUMBER:
Common Stock: 683399-10-9
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ITEM 3.
Not applicable
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ITEM 4. OWNERSHIP.
(a) Amount Beneficially Owned:
Common Stock: 1,400,756 shares
(b) Percent of Class:
Common Stock: 14.7%
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote:
1,400,756 shares of Common Stock
(ii) shared power to vote or to direct the vote:
None
(iii) sole power to dispose or to direct the disposition of:
1,400,756 shares of Common Stock
(iv) shared power to dispose or to direct the disposition of:
None
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ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.
Not applicable
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ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.
Not applicable
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ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE
SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY.
Not applicable
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ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.
Not applicable
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ITEM 9. NOTICE OF DISSOLUTION OF GROUP.
Not applicable
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ITEM 10. CERTIFICATION.
Not applicable
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SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.
CHIRON CORPORATION
Date: February 6, 1997 By: /s/William G. Green
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Signature
William G. Green, Senior Vice President,
Secretary and General Counsel
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Name/Title
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