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^*

COLVIN DONALD A

(Last)

(First)

(Middle)

5005 EAST MCDOWELL ROAD

(Street)

PHOENIX

85008

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
ON SEMICONDUCTOR CORP [ ONNN ]

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

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	Exec VP & CFO

3. Date of Earliest Transaction (Month/Day/Year)
10/10/2008

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	10/10/2008		A		1,412⁽¹⁾	A	$0.0000	357,033⁽²⁾	D
Common	03/05/2012		A		95,238⁽³⁾	A	$0.0000	830,119	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)
Stock Option (right to buy)	$8.4	03/05/2012		A		190,477⁽⁴⁾		03/05/2013	03/05/2022	Common	190,477	$0.0000	190,477	D

Explanation of Responses:

1. 2,000 shares of Catalyst Semiconductor were previously owned by the Reporting Person prior to the merger of Catalyst Semiconductor into ON Semiconductor Corporation. As a result of the merger, each Catalyst share was exchanged for .706 ON Semiconductor shares, resulting in the acquisition of 1,412 shares of ON Semiconductor stock by the Reporting Person. This transaction was not previously reported due to a clerical error.

2. Balance as of transaction date, October 10, 2008.

3. On February 16, 2012, the Compensation Committee of the Board of Directors awarded these restricted stock units to the Reporting Person under the Issuer's Amended and Restated Stock Incentive Plan ("Plan"), with an effective grant date of March 5, 2012 and with equal pro rata vesting over a 3-year period beginning on the first anniversary of the grant date, subject to the terms and conditions of the Plan and the relevant award agreement. This award may only be settled in shares of the Issuer's common stock upon vesting. The award was for no consideration other than service as an executive officer of the Issuer.

4. On February 16, 2012, the Compensation Committee of the Board of Directors granted this stock option to the Reporting Person under the Issuer's Amended and Restated Stock Incentive Plan ("Plan"), with an effective grant date of March 5, 2012. The stock option will vest over a 4-year period beginning on the first anniversary of the grant date at a rate of 25% and thereafter on a quarterly basis at a rate of 6.25%, subject to the terms and conditions of the Plan and the related option agreement. The exercise price is the closing price on the grant date. This award was for no consideration other than service as an executive officer of the Issuer.

Remarks:

Judith A. Boyle is signing on behalf of the Reporting Person pursuant to a Power of Attorney attached hereto as an Exhibit. colvin2012poa.txt

	Judith A. Boyle, Attorney-in-Fact	03/07/2012
	** 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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