Aon plc — Director's Dealing 2010

Mar 16, 2010

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AON CORP (AOC)
CIK: 0000315293
Period of Report: 2010-03-13

Reporting Person: Hayley Kathryn (ACW - Chief Executive Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2010-03-13	Common Stock	M	2404	—	Acquired	3393	Direct
2010-03-13	Common Stock	F	708	$41.54	Disposed	2685	Direct
2010-03-15	Common Stock	M	2920	—	Acquired	5605	Direct
2010-03-15	Common Stock	F	860	$41.90	Disposed	4745	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2010-03-13	Restricted Stock Unit Award (Right to Receive)	$	M	2404	Disposed	2010-03-13	Common Stock (2404)	Direct
2010-03-15	Restricted Stock Unit Award (Right to Receive)	$	M	2920	Disposed	2010-03-15	Common Stock (2920)	Direct

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 231 shares held through the Aon employee stock purchase plan.