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^*

LIEB PETER M

(Last)

(First)

(Middle)

AON CORPORATION - CORPORATE LAW DEPT

200 EAST RANDOLPH STREET, 8TH FLOOR

(Street)

CHICAGO

60601

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
AON CORP [ AOC ]

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

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	EVP & General Counsel

3. Date of Earliest Transaction (Month/Day/Year)
02/25/2011

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	02/25/2011		M⁽¹⁾		1,708	A	⁽¹⁾	1,820.443⁽⁸⁾	D
Common Stock	02/25/2011		F⁽²⁾		538	D	$52.49	1,282.443⁽⁸⁾	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)
Restricted Stock Unit Award (Right to Receive)	⁽³⁾	02/25/2011		M			1,708	02/25/2011	02/25/2011	Common Stock	1,708	$0	3,145	D
Phantom Stock	⁽⁴⁾	02/28/2011		A		610.01⁽⁷⁾		⁽⁵⁾	⁽⁵⁾	Common Stock	610.01	$52.68	828.64⁽⁶⁾	D

Explanation of Responses:

1. Shares of common stock acquired upon the vesting of a restricted stock unit award.

2. Shares of common stock withheld by the issuer for the payment of withholding taxes in connection with the vesting of a restricted stock unit award.

3. The restricted stock unit award converts to shares of common stock on a 1-for-1 basis.

4. Each share of phantom stock acquired under the issuer's deferred compensation plan represents the right to receive one share of Aon common stock or the cash value thereof.

5. Shares of phantom stock are payable in cash in ten annual installments following the reporting person's retirement. Subject to the issuer's compliance procedures for its Section 16 reporting officers, the reporting person may transfer shares of common stock into an alternative investment account under the issuer's deferred compensation plan.

6. Includes shares acquired pursuant to dividend reinvestment.

7. This amount represents phantom shares acquired in connection with the deferral of a portion of the reporting person's short-term incentive for 2010 performance and a deferral of a portion of the reporting person's base salary.

8. Includes 112.443 shares held pursuant to the Aon employee stock purchase plan.

	/s/ Jennifer L. Kraft - Jennifer L. Kraft pursuant to a power of attorney from Peter Lieb	03/01/2011
	** 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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