Aon plc — Director's Dealing 2012

May 17, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Aon plc (AON)
CIK: 0000315293
Period of Report: 2012-05-15

Reporting Person: McGill Stephen P (Chairman/CEO - ARS)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-05-15	Class A Ordinary Shares	M	13750	—	Acquired	207452	Direct
2012-05-15	Class A Ordinary Shares	F	5699	$47.70	Disposed	201753	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2012-05-15	Restricted Stock Unit Award (Right to Receive)	$	M	13750	Disposed	2012-05-15	Class A Ordinary Shares (13750)	Direct

Footnotes

F1: Class A Ordinary Shares acquired upon the vesting of a restricted stock unit award.

F2: Class A Ordinary Shares 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 Class A Ordinary Shares on a 1-for-1 basis.