Aon plc — Director's Dealing 2011

Feb 22, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AON CORP (AOC)
CIK: 0000315293
Period of Report: 2011-02-17

Reporting Person: O'Connor Michael J (ARS - COO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-02-17	Common Stock	A	41625	—	Acquired	41625	Direct
2011-02-17	Common Stock	F	15335	$51.92	Disposed	26290	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-02-17	Restricted Stock Unit Award (Right to Receive)	$	A	6741	Acquired	2014-02-17	Common Stock (6741)	Direct

Footnotes

F1: Represents shares of common stock issued upon the settlement of performance share units originally granted approximately three years ago under the third cycle of the Leadership Performance Program ("LPP3") on March 13, 2008. The number of shares issued was determined by the Organization and Compensation Committee of Aon's Board of Directors on February 17, 2011 based upon Aon's performance relative to a cumulative adjusted three year earnings per share target for the period beginning January 1, 2008 and ending December 31, 2010. In accordance with the terms of LPP3, and the achievement of specified growth targets under LPP3, settlement occurred at 130% of the original target value. The terms of LPP3 are more fully described in a Current Report on Form 8-K filed with the SEC on March 19, 2008, and in the plan document filed as Exhibit 10.3 to Aon's Quarterly Report on Form 10-Q for the quarter ended March 31, 2008 filed with the SEC on May 9, 2008.

F2: Shares of common stock withheld by the issuer for the payment of withholding taxes in connection with the settlement of a performance share unit award.

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

F4: The restricted stock unit award will vest in accordance with the terms of the Aon Stock Incentive Plan as follows: 33 1/3% of the awards will vest on each of the first through third anniversaries of the date of grant.