SEC FORM 4

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

WHEELER CRAIG A

(Last)

(First)

(Middle)

4560 HORTON STREET

(Street)

EMERYVILLE

94608

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
CHIRON CORP [ CHIR ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	V.P.; Pres., Chiron BioPharma

3. Date of Earliest Transaction (Month/Day/Year)
04/19/2006

4. If Amendment, Date of 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

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	04/19/2006		D⁽¹⁾		7,041	D	$48	0	D

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 Securities Underlying Derivative Security (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: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
Employee Stock Option (Right to Buy)	$46.97	04/19/2006		D⁽²⁾			200,000	⁽³⁾	04/19/2006	Common Stock	200,000	$1.03⁽²⁾	0	D
Employee Stock Option (Right to Buy)	$46.97	04/19/2006		D⁽²⁾			23,000	⁽³⁾	04/19/2006	Common Stock	23,000	$1.03⁽²⁾	0	D
Employee Stock Option (Right to Buy)	$43.18	04/19/2006		D⁽²⁾			85,000	⁽³⁾	04/19/2006	Common Stock	85,000	$4.82⁽²⁾	0	D
Employee Stock Option (Right to Buy)	$42.535	04/19/2006		D⁽²⁾			40,625	⁽³⁾	04/19/2006	Common Stock	40,625	$5.465⁽²⁾	0	D
Employee Stock Option (Right to Buy)	$36.335	04/19/2006		D⁽²⁾			50,000	⁽³⁾	04/19/2006	Common Stock	50,000	$11.665⁽²⁾	0	D
Employee Stock Option (Right to Buy)	$36.335	04/19/2006		D⁽²⁾			100,000	⁽³⁾	04/19/2006	Common Stock	100,000	$11.665⁽²⁾	0	D
Employee Stock Option (Right to Buy)	$33.88	04/19/2006		D⁽²⁾			90,000	⁽³⁾	04/19/2006	Common Stock	90,000	$14.12⁽²⁾	0	D
Performance Share Right Award	⁽⁴⁾	04/19/2006		A⁽⁵⁾		12,000		⁽⁶⁾	04/19/2006	Common Stock	12,000	$0	12,000	D
Performance Share Right Award	⁽⁴⁾	04/19/2006		D⁽⁷⁾			12,000	⁽⁶⁾	04/19/2006	Common Stock	12,000	$48⁽⁷⁾	0	D
Performance Share Right Award	⁽⁴⁾	04/19/2006		A⁽⁸⁾		14,000		⁽⁶⁾	04/19/2006	Common Stock	14,000	$0	14,000	D
Performance Share Right Award	⁽⁴⁾	04/19/2006		D⁽⁷⁾			14,000	⁽⁶⁾	04/19/2006	Common Stock	14,000	$48⁽⁷⁾	0	D
Restricted Stock Units	⁽⁴⁾	04/19/2006		D⁽⁹⁾			2,200	⁽¹⁰⁾	04/19/2006	Common Stock	2,200	$48⁽⁹⁾	0	D

Explanation of Responses:

1. The disposition was effected pursuant to the terms of the merger agreement between the Issuer and Novartis AG dated as of October 30, 2005 and as subsequently amended April 3, 2006 (the "Merger Agreement"), and involved the exchange of each share for a cash payment in the amount of $48. The disposition was approved by the Compensation Committee of the Issuer's Board of Directors and is accordingly an exempt transaction pursuant to SEC Rule 16b-3(e).

2. The option was cancelled pursuant to the terms of the Merger Agreement in exchange for a cash payment per cancelled option share equal to $48 less the exercise price per share in effect for that option. Such disposition of the option was approved by the Compensation Committee of the Issuer's Board of Directors and is accordingly an exempt transaction pursuant to SEC Rule 16b-3(e).

3. The option was vested and fully exercisable as to all the shares at the time of cancellation.

4. One-for-One

5. Represents a performance share award made on June 1, 2004 and structured to vest upon the Issuer's attainment of certain pre-established performance objectives over a designated period measured from June 1, 2004 to December 31, 2006. However, pursuant to the terms of such award, vesting occurred at target level on an accelerated basis immediately prior to the change in control transaction effected on April 19, 2006 pursuant to the Merger Agreement. The award was made to the Reporting Person in a transaction exempt under SEC Rule 16b-3(d).

6. The share rights award vested in full on an accelerated basis immediately prior to the closing of the change in control transaction effected on April 19, 2006 pursuant to the Merger Agreement.

7. The share rights were cancelled pursuant to the terms of the Merger Agreement in exchange for a cash payment equal to $48 per share of the Issuer's common stock underlying the cancelled share rights. Such disposition of the share rights was approved by the Compensation Committee of the Issuer's Board of Directors and is accordingly an exempt transaction pursuant to SEC Rule 16b-3(e).

8. Represents a performance share award made on February 22, 2005 and structured to vest upon the Issuer's attainment of certain pre-established performance objectives over a designated period measured from February 22, 2005 to August 21, 2007. However, pursuant to the terms of such award, vesting occurred at target level on an accelerated basis immediately prior to the change in control transaction effected on April 19, 2006 pursuant to the Merger Agreement. The award was made to the Reporting Person in a transaction exempt under SEC Rule 16b-3(d).

9. The stock units were cancelled pursuant to the terms of the Merger Agreement in exchange for a cash payment equal to $48 per share of the Issuer's common stock underlying the cancelled share rights. Such disposition of the share rights was approved by the Compensation Committee of the Issuer's Board of Directors and is accordingly an exempt transaction pursuant to SEC Rule 16b-3(e).

10. The stock units vested in full on an accelerated basis in connection with the closing of the change in control transaction effected on April 19, 2006 pursuant to the Merger Agreement.

Remarks:

	Craig A. Wheeler by Naima Robinson as Atty-in-Fact	04/19/2006
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
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