Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
RYAN PATRICK G
   2. Issuer Name and Ticker or Trading Symbol
AON CORP [AOC] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Executive Chairman
(Last)
(First)
(Middle)
C/O AON CORPORATE LAW DEPARTMENT, 8TH FLOOR, 200 EAST RANDOLPH DRIVE		 3. Date of Earliest Transaction (Month/Day/Year)
08/15/2007
(Street)

CHICAGO, IL 60601		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Options (Right to Buy) $ 30.7813 08/15/2007   D     300,000   (1)(2) 11/16/2010 Common Stock 300,000 (1) (2) 0 D  
Employee Stock Options (Right to Buy) $ 31.9375 08/15/2007   A   300,000     (1)(2) 11/16/2010 Common Stock 300,000 (1) (2) 300,000 D  
Employee Stock Options (Right to Buy) $ 36.875 08/15/2007   D     250,000   (3)(4) 04/22/2012 Common Stock 250,000 (3) (4) 0 D  
Employee Stock Options (Right to Buy) $ 39.25 08/15/2007   A   250,000     (3)(4) 04/22/2012 Common Stock 250,000 (3) (4) 250,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
RYAN PATRICK G
C/O AON CORPORATE LAW DEPARTMENT
8TH FLOOR, 200 EAST RANDOLPH DRIVE
CHICAGO, IL 60601		   X     Executive Chairman  

Signatures

 /s/ Jennifer L. Kraft, pursuant to a Power of Attorney from Patrick G. Ryan   08/17/2007
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) In a Form 4 filed in December 2000, the reporting person reported that, on November 16, 2000, he was granted an employee stock option covering 300,000 shares of common stock, having an exercise price of $30.7813 per share and vesting in three annual installments beginning on November 16, 2002. Following a review of the issuer's stock option award practices, it was determined that the exercise price for this option should be adjusted to $31.9375 per share to reflect the fair market value of the issuer's common stock on the accounting measurement date. As a result, the reporting person and the issuer agreed to amend the option to provide that the option will have an exercise price of $31.9375 per share.
(2) All other terms and conditions of the option award remain the same, including the vesting schedule described above. The amendment is reported in this Form 4 as a cancellation of the original option and the grant of a replacement option. For additional information, please see the issuer's Current Report on Form 8-K, filed with the Commission on August 15, 2007.
(3) In a Form 5 filed in February 2003, the reporting person reported that, on April 22, 2002, he was granted an employee stock option covering 250,000 shares of common stock, having an exercise price of $36.875 per share and vesting in three annual installments beginning on April 22, 2004. Following a review of the issuer's stock option award practices, it was determined that the exercise price for this option should be adjusted to $39.250 per share to reflect the fair market value of the issuer's common stock on the accounting measurement date. As a result, the reporting person and the issuer agreed to amend the option to provide that the option will have an exercise price of $39.250 per share.
(4) All other terms and conditions of the option award remain the same, including the vesting schedule described above. The amendment is reported in this Form 4 as a cancellation of the original option and the grant of a replacement option. For additional information, please see the issuer's Current Report on Form 8-K, filed with the Commission on August 15, 2007.

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