8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of report (Date of earliest event reported): November 23, 2009

Aon Corporation(Exact Name of Registrant as Specified in Charter)

Delaware	1-7933	36-3051915
(State or Other Jurisdiction of Incorporation)	(Commission File Number)	(IRS Employer Identification No.)

200 East Randolph Street, Chicago, Illinois
(Address of Principal Executive Offices) 60601
(Zip Code)

Registrant’s telephone number, including area code: (312) 381-1000

Not Applicable
(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

oWritten communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

oSoliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

oPre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

oPre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01. Other Events.

On November 23, 2009, Aon Corporation issued a press release announcing that it will change the ticker symbol for its common stock listed on the New York Stock Exchange to “AON” from “AOC.”  The change will become effective at the start of trading on Tuesday, December 1, 2009.

A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

Item 9.01. Financial Statements and Exhibits.

(a)—(c)Not applicable.

(d)              Exhibits:

Exhibit Number	Description of Exhibit
99.1	Press Release issued by Aon Corporation on November 23, 2009.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	Aon CORPORATION
	By:	/s/ Richard E. Barry
		Richard E. Barry
		Vice President and Deputy General Counsel
Date: November 24, 2009

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EXHIBIT INDEX

Exhibit Number	Description of Exhibit
99.1	Press Release issued by Aon Corporation on November 23, 2009.

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EX-99.1

Exhibit 99.1

Investor Relations

News from Aon

Aon Corporation to Change NYSE Ticker Symbol to AON

CHICAGO, IL — November 23, 2009 - Aon Corporation (NYSE: AOC) today announced that it will change the ticker symbol for its common stock listed on the New York Stock Exchange to “AON” from “AOC”. The change will become effective at the start of trading on Tuesday, December 1, 2009.

“The Aon name is globally recognized as the industry-leading provider of risk and human capital solutions. Changing our ticker symbol to ‘AON’ extends this recognition and links our common stock listing with our brand,” said Greg Case, president and chief executive officer, Aon Corporation.

About Aon

Aon Corporation (NYSE: AOC - News) is the leading global provider of risk management services, insurance and reinsurance brokerage, and human capital consulting. Through its more than 36,000 colleagues worldwide, Aon readily delivers distinctive client value via innovative and effective risk management and workforce productivity solutions. Aon’s industry-leading global resources and technical expertise are delivered locally through more than 500 offices in more than 120 countries. Named the world’s best broker by Euromoney magazine’s 2008 and 2009 Insurance Survey, Aon also ranked highest on Business Insurance’s listing of the world’s largest insurance brokers based on commercial retail, wholesale, reinsurance and personal lines brokerage revenues in 2008 and 2009. A.M. Best deemed Aon the number one insurance broker based on brokerage revenues in 2007, 2008, and 2009, and Aon was voted best insurance intermediary, best reinsurance intermediary and best employee benefits consulting firm in 2007 and 2008 by the readers of Business Insurance. For more information on Aon, log onto http://www.aon.com.

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Investor Contact:	Media Contact:
Scott Malchow	David Prosperi
Vice President, Investor Relations	Vice President, Global Public Relations
312-381-3983	312-381-2485