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SECURITIES AND EXCHANGE COMMISSION
 WASHINGTON, 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): April 5, 2002

Aon CORPORATION
 (Exact name of Registrant as Specified in Its 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	
 	
60601	
(Address of Principal Executive Offices)	 	(Zip Code)	

 	

 	
Registrant's Telephone Number, Including Area Code: (312) 381-1000
Not Applicable
 (Former Name or Former Address, if Changed Since Last Report)

 Item 7. Financial Statements, Pro Forma Financial Information and Exhibits.
(a)
Not applicable.

(b)
Pro Forma Financial Information.
Aon Corporation
Pro Forma Condensed Consolidated Financial Information
        Aon Corporation is a holding company that is comprised of a family of insurance brokerage, consulting and insurance underwriting subsidiaries. Through our insurance brokerage and other services and consulting operations, we offer commercial insurance brokerage, alternative risk solutions, risk management, employee benefit and human capital consulting and underwriting management services. In addition, our insurance underwriting businesses provide a variety of insurance products, including supplemental accident and health coverage, extended warranties and specialty property and casualty products. Our revenues were $7.7 billion in 2001. Based on 2001 revenues, we are the second largest insurance brokerage company in the world.
        On April 20, 2001, Aon's Board of Directors approved, in principle, a plan to spin-off our insurance underwriting businesses to Aon's common stockholders, creating two independent publicly traded companies. The spin-off would take the form of a tax-free stock dividend of the outstanding shares of common stock of Combined Specialty Group, Inc. (CSG), formerly known as Combined Specialty Corporation, a new company formed to hold our underwriting businesses. The transaction requires final Board approval, a favorable Internal Revenue Service tax ruling and certain insurance regulatory approvals, and is currently expected to be completed in spring 2002.
        The underwriting businesses we plan to spin-off are mainly reflected in our insurance underwriting segment, one of our three operating segments. This segment currently provides supplemental accident and health, life insurance, extended warranty and specialty property and casualty insurance products through five major subsidiaries: Combined Insurance Company of America, Combined Life Insurance Company of New York, Combined Specialty Insurance Company, London General Insurance Company Limited and Aon Warranty Group, Inc. These subsidiaries hold virtually all of our fixed-maturity investments (principally reflected in our insurance underwriting segment) and equity security investments and limited partnership interests (primarily reflected in our corporate segment). On December 31, 2001, Aon securitized $450 million of its limited partnership investments plus associated limited partnership commitments, which represented the majority of its limited partnership interests. Aon received a combination of cash and securities in connection with the securitization. In 2001, the underwriting businesses invested $227 million to obtain an ownership interest in Endurance Specialty Insurance Ltd. (Endurance), a newly formed Bermuda-based insurer, which will offer property and casualty insurance and reinsurance on a worldwide basis.
2

Aon Corporation
Pro Forma Condensed Consolidated Financial Information
        Attached hereto is a Pro Forma Condensed Consolidated Statement of Income for the year ended December 31, 2001 on a basis as if the spin-off occurred on January 1, 2001. Also attached is a Pro Forma Condensed Consolidated Statement of Financial Position as of December 31, 2001, presented on a basis of recording the effect of the spin-off as of December 31, 2001. The Pro Forma Condensed Consolidated Financial Information is based on various assumptions made by Aon's management as of the current date, including assumptions regarding allocations of assets and liabilities that are expected to be transferred to CSG prior to the spin-off. The actual basis on which the spin-off is effected may vary from the assumptions based upon the terms of any final Internal Revenue Service approval, Board of Directors approval, regulatory approval and other factors. The Pro Forma Condensed Consolidated Financial Information does not purport to be indicative of the financial condition or results of operations that would actually have been reported had the spin-off been completed on the date indicated or that may be reported in the future. It does not reflect the effect of any possible financings. The historical Aon and the CSG financial information has been derived from the audited financial statements of the respective companies. The adjustments made to the historical financial information of Aon and CSG are unaudited.
        This Pro Forma Condensed Consolidated Financial Information does not include certain disclosures required in accordance with accounting principles generally accepted in the United States and, therefore, should be read in conjunction with Aon's and CSG's respective historical financial statements and notes thereto. This information should also be read in conjunction with Aon's and CSG's respective management's discussion and analysis of financial condition and results of operations as reflected in recent Securities and Exchange Commission filings.
Dated: April 5, 2002
3

Aon Corporation
Pro Forma Condensed Consolidated Statement of Income

 	 	Year ended December 31, 2001
	 	
 	 	 	 	Pro Forma Adjustments
	 	 	 	
 	 	Historical
Aon
	 	Less
CSG
	 	Plus
Adjustments
	 	Pro
Forma
Aon
	 	
 	 	(millions, except per share data)
	 	
Revenue	 	 	 	 	 	 	 	 	 	 	 	 	 	
 	Brokerage commissions and fees (5)	 	$	5,436	 	$	213	 	$	(52	)	$	5,171	 	
 	Premiums and other	 	 	2,027	 	 	2,027	 	 	 	 	 	—	 	
 	Investment income (1,2,4)	 	 	213	 	 	88	 	 	20	 	 	145	 	
 	 		 		 		 		 	
 	 	Total revenue	 	 	7,676	 	 	2,328	 	 	(32	)	 	5,316	 	
Expenses	 	 	 	 	 	 	 	 	 	 	 	 	 	
 	General expenses (5)	 	 	5,813	 	 	1,091	 	 	(52	)	 	4,670	 	
 	Benefits to policyholders	 	 	1,111	 	 	1,111	 	 	 	 	 	—	 	
 	Interest expense (3,4)	 	 	127	 	 	42	 	 	20	 	 	105	 	
 	Amortization of intangible assets	 	 	158	 	 	10	 	 	 	 	 	148	 	
 	Unusual charges—World Trade Center	 	 	68	 	 	45	 	 	 	 	 	23	 	
 	 		 		 		 		 	
 	 	Total expenses	 	 	7,277	 	 	2,299	 	 	(32	)	 	4,946	 	

Income Before Income Tax and Minority Interest	

399	

29	

 	

370	
 	
 	Provision for income tax	 	 	156	 	 	11	 	 	 	 	 	145	 	
 	 		 		 		 		 	
Income Before Minority Interest	 	 	243	 	 	18	 	 	 	 	 	225	 	
 	Minority interest—8.205% trust preferred capital securities	 	 	(40	)	 	 	 	 	 	 	 	(40	)	
 	 		 		 		 		 	
Net Income	 	$	203	 	$	18	 	$	—	 	$	185	 	
 	 		 		 		 		 	
Net Income Available for Common Stockholders	 	$	200	 	 	 	 	 	 	 	$	182	 	
 	 		 	 	 	 	 	 	 		 	
Average Shares Outstanding—Basic	 	 	269	 	 	 	 	 	 	 	 	269	 	
Average Shares Outstanding—Dilutive	 	 	272	 	 	 	 	 	 	 	 	272	 	

Basic Net Income Per Share	
 	
$	
0.74	

 	

 	
 	
$	
0.68	

Dilutive Net Income Per Share:	 	 	 	 	 	 	 	 	 	 	 	 	 	
 	Income before unusual and special charges	 	$	1.37	 	 	 	 	 	 	 	$	1.15	 	
 	Unusual charges—World Trade Center	 	 	(0.15	)	 	 	 	 	 	 	 	(0.05	)	
 	Special charges	 	 	(0.49	)	 	 	 	 	 	 	 	(0.43	)	
 	 		 	 	 	 	 	 	 		 	
 	 	Net Income	 	$	0.73	 	 	 	 	 	 	 	$	0.67	 	

 	 	 	 	 	 	 	 	 	
Notes:	 	 	 	 	 	 	 	 	 	
1.    Historical Aon investment income by segment is as follows:	 	 	 	 	 	 	
 	Insurance brokerage and other services	 	$	156	 	 	 	 	 	 	
 	Consulting	 	 	5	 	 	 	 	 	 	
 	Insurance underwriting	 	 	223	 	 	 	 	 	 	
 	Corporate and other	 	 	(171	)	 	 	 	 	 	
 	 		 	 	 	 	 	 	
 	 	Total	 	$	213	 	 	 	 	 	 	
 	 		 	 	 	 	 	 	
2.
CSG investment income includes a loss of $94 million for the change in valuation on private limited partnership investments. Reference should be made to comments on the previous page regarding the limited partnership securitization and investment in Endurance.
4

3.
As part of the spin-off, it is anticipated that CSG will effectively be allocated debt from Aon. The interest on this allocation is $42 million for the twelve months ended December 31, 2001.

4.
Investment income and interest expense have been increased by $20 million to reflect interest on debt owed to CSG by Aon which was previously eliminated in consolidation.

5.
Brokerage commissions and fees and general expenses have been decreased by $52 million to adjust for certain amounts reclassified for CSG's separate company financial statements.
Dated: April 5, 2002
5

Aon Corporation
Pro Forma Condensed Consolidated Statement of Financial Position

 	 	As of December 31, 2001
	 	
 	 	 	 	Pro Forma Adjustments
	 	 	 	
 	 	Historical
Aon
	 	Less
CSG
	 	Plus
Adjustments
	 	Pro
Forma
Aon
	 	
 	 	(millions)
	 	
Assets:	 	 	 	 	 	 	 	 	 	 	 	 	 	
 	Fixed maturities at fair value (1)	 	$	2,149	 	$	2,425	 	$	313	 	$	37	 	
 	Equity securities at fair value	 	 	382	 	 	363	 	 	 	 	 	19	 	
 	Short-term investments	 	 	2,975	 	 	696	 	 	 	 	 	2,279	 	
 	Other investments	 	 	640	 	 	605	 	 	 	 	 	35	 	
 	 		 		 		 		 	
 	 	 	Total Investments	 	 	6,146	 	 	4,089	 	 	313	 	 	2,370	 	
 	Cash	 	 	439	 	 	82	 	 	 	 	 	357	 	
 	Receivables	 	 	7,986	 	 	867	 	 	 	 	 	7,119	 	
 	Intangible assets	 	 	4,084	 	 	317	 	 	 	 	 	3,767	 	
 	Other assets	 	 	3,731	 	 	1,964	 	 	 	 	 	1,767	 	
 	 		 		 		 		 	
 	TOTAL ASSETS	 	$	22,386	 	$	7,319	 	$	313	 	$	15,380	 	
 	 		 		 		 		 	
Liabilities and Stockholders' Equity:	 	 	 	 	 	 	 	 	 	 	 	 	 	
 	Insurance premiums payable	 	$	8,233	 	$	—	 	$	—	 	$	8,233	 	
 	Policy liabilities	 	 	4,990	 	 	4,990	 	 	 	 	 	—	 	
 	General liabilities	 	 	 	 	 	 	 	 	 	 	 	 	 	
 	 	General expenses	 	 	1,770	 	 	140	 	 	 	 	 	1,630	 	
 	 	Short-term borrowings	 	 	257	 	 	 	 	 	 	 	 	257	 	
 	 	Notes payable (1,2)	 	 	1,694	 	 	600	 	 	313	 	 	1,407	 	
 	 	Other liabilities	 	 	1,071	 	 	413	 	 	 	 	 	658	 	
 	 		 		 		 		 	
 	 	TOTAL LIABILITIES	 	 	18,015	 	 	6,143	 	 	313	 	 	12,185	 	
 	Redeemable Preferred Stock	 	 	50	 	 	 	 	 	 	 	 	50	 	
 	Company-obligated mandatorily redeemable
preferred capital securities of subsidiary
trust holding solely the company's junior
subordinated debentures	 	 	800	 	 	 	 	 	 	 	 	800	 	
 	
Stockholders' equity:	

 	

 	

 	

 	
 	
 	 	Common stock	 	 	293	 	 	 	 	 	 	 	 	293	 	
 	 	Paid-in-capital	 	 	1,654	 	 	 	 	 	 	 	 	1,654	 	
 	 	Accumulated other comprehensive loss	 	 	(535	)	 	(135	)	 	 	 	 	(400	)	
 	 	Retained earnings	 	 	3,077	 	 	1,311	 	 	 	 	 	1,766	 	
 	 	Less: Treasury stock at cost	 	 	(786	)	 	 	 	 	 	 	 	(786	)	
 	 	          Deferred compensation	 	 	(182	)	 	 	 	 	 	 	 	(182	)	
 	 		 		 		 		 	
 	 	TOTAL STOCKHOLDERS' EQUITY	 	 	3,521	 	 	1,176	 	 	—	 	 	2,345	 	
 	 		 		 		 		 	
 	TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	 	$	22,386	 	$	7,319	 	$	313	 	$	15,380	 	

Notes:
1.
Fixed maturities and notes payable have been increased by $313 million to reflect debt owed to CSG by Aon which was previously eliminated in consolidation.

2.
As part of the spin-off, it is anticipated that CSG will effectively be allocated $600 million of debt from Aon.
Dated: April 5, 2002
(c)
Exhibits.
None.
6

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/   RAYMOND I. SKILLING       

Raymond I. Skilling
 Executive Vice President and Chief Counsel	
Date: April 5, 2002

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Item 7. Financial Statements, Pro Forma Financial Information and Exhibits.