Aon plc — Director's Dealing 2012

Feb 28, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AON CORP (AON)
CIK: 0000315293
Period of Report: 2012-02-25

Reporting Person: Besio Gregory J (EVP/Chief HR Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-02-25	Common Stock	M	2277	—	Acquired	87528.682	Direct
2012-02-25	Common Stock	F	944	$47.53	Disposed	86584.682	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2012-02-25	Restricted Stock Unit Award (Right to Receive)	$	M	2277	Disposed	2012-02-25	Common Stock (2277)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	7197	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.