Aon plc — Director's Dealing 2011

Feb 23, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AON CORP (AOC)
CIK: 0000315293
Period of Report: 2011-02-20

Reporting Person: FARMER JEREMY G O (Senior VP & Head of HR)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-02-20	Common Stock	M	839	—	Acquired	58352	Direct
2011-02-20	Common Stock	F	264	$52.93	Disposed	58088	Direct
2011-02-22	Common Stock	M	1917	—	Acquired	60005	Direct
2011-02-22	Common Stock	F	735	$52.24	Disposed	59270	Direct
2011-02-22	Common Stock	M	3920	$25.51	Acquired	63190	Direct
2011-02-22	Common Stock	F	1889	$52.93	Disposed	61301	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-02-20	Restricted Stock Unit Award (Right to Receive)	$	M	839	Disposed	2011-02-20	Common Stock (839)	Direct
2011-02-22	Restricted Stock Unit Award (Right to Receive)	$	M	1917	Disposed	2011-02-22	Common Stock (1917)	Direct
2011-02-22	Employee Stock Option (Right to Buy)	$25.51	M	3920	Disposed	2015-07-14	Common Stock (3920)	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 924 shares held pursuant to the Aon employee stock purchase plan.

F5: The original option grant of 7,970 shares vested as follows: 130 shares vested on July 14, 2007, and 3,920 shares vested on each of July 14, 2008 and July 14, 2009.