Aon plc — Director's Dealing 2010

Feb 23, 2010

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AON CORP (AOC)
CIK: 0000315293
Period of Report: 2010-02-20

Reporting Person: Besio Gregory J (EVP/CAO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2010-02-20	Common Stock	M	1018	—	Acquired	3189	Direct
2010-02-20	Common Stock	F	340	$40.57	Disposed	2849	Direct
2010-02-22	Common Stock	M	2192	—	Acquired	5041	Direct
2010-02-22	Common Stock	F	646	$40.46	Disposed	4395	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2010-02-20	Restricted Stock Unit Award (Right to Receive)	$	M	1018	Disposed	2010-02-20	Common Stock (1018)	Direct
2010-02-22	Restricted Stock Unit Award (Right to Receive)	$	M	2192	Disposed	2010-02-22	Common Stock (2192)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	4585	Indirect

Footnotes

F1: Shares of common stock acquired upon the vesting of a restricted stock unit award.

F2: 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.

F3: The restricted stock unit award converts to shares of common stock on a 1-for-1 basis.

F4: Includes 378 shares held through the Aon employee stock purchase plan.