Aon plc — Major Shareholding Notification 2010

Mar 17, 2010

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13D/A

*(Rule 13d-101)*

*INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO 13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO 13d-2(a)*

*Under the Securities Exchange Act of 1934 (Amendment No. 10)**

*Aon Corporation*

(Name of Issuer)

*Common Stock, $1.00 Par Value*

(Title of Class of Securities)

*200166106*

(CUSIP Number)

*Lisa J. Reátegui*

*Sidley Austin LLP*

*One South Dearborn Street*

*Chicago, Illinois 60603*

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

*February 25, 2010*

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. o

*Note* : Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

• The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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| CUSIP No. 200166106 — 1. | Names of Reporting Persons. I.R.S. Identification
Nos. of above persons (entities only) Patrick G. Ryan | |
| --- | --- | --- |
| 2. | Check the Appropriate Box
if a Member of a Group (See Instructions) | |
| | (a) | o |
| | (b) | o |
| 3. | SEC Use Only | |
| 4. | Source of Funds (See
Instructions) OO | |
| 5. | Check if Disclosure of Legal Proceedings Is
Required Pursuant to Items 2(d) or 2(e) o | |
| 6. | Citizenship or Place of Organization U.S.A. | |
| Number of Shares Beneficially Owned by Each Reporting Person With | 7. | Sole Voting Power 4,944,844 |
| | 8. | Shared Voting Power 11,801,904 |
| | 9. | Sole Dispositive Power 4,472,922 |
| | 10. | Shared Dispositive Power 12,273,826 |
| 11. | Aggregate Amount
Beneficially Owned by Each Reporting Person 17,330,690 | |
| 12. | Check if the Aggregate
Amount in Row (11) Excludes Certain Shares (See Instructions) o | |
| 13. | Percent of Class
Represented by Amount in Row (11) 6.49% | |
| 14. | Type of Reporting Person
(See Instructions) IN | |

2

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| CUSIP No. 200166106 — 1. | Names of Reporting Persons. I.R.S. Identification
Nos. of above persons (entities only) Shirley W. Ryan | |
| --- | --- | --- |
| 2. | Check the Appropriate Box
if a Member of a Group (See Instructions) | |
| | (a) | o |
| | (b) | o |
| 3. | SEC Use Only | |
| 4. | Source of Funds (See
Instructions) OO | |
| 5. | Check if Disclosure of Legal Proceedings Is
Required Pursuant to Items 2(d) or 2(e) o | |
| 6. | Citizenship or Place of Organization U.S.A. | |
| Number of Shares Beneficially Owned by Each Reporting Person With | 7. | Sole Voting Power 583,942 |
| | 8. | Shared Voting Power 11,801,904 |
| | 9. | Sole Dispositive Power 583,942 |
| | 10. | Shared Dispositive Power 12,273,826 |
| 11. | Aggregate Amount
Beneficially Owned by Each Reporting Person 17,330,690 | |
| 12. | Check if the Aggregate
Amount in Row (11) Excludes Certain Shares (See Instructions) o | |
| 13. | Percent of Class
Represented by Amount in Row (11) 6.49% | |
| 14. | Type of Reporting Person
(See Instructions) IN | |

3

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CUSIP No. 200166106

*Introduction*

This filing is being made jointly by Patrick G. Ryan and Shirley W. Ryan and relates to the common stock, $1.00 par value (“Aon Common Stock”), of Aon Corporation, a Delaware corporation (“Aon”). These individuals own Aon Common Stock directly and act as trustees of various trusts to benefit members of the Ryan family. This filing amends the Schedule 13D previously filed by Patrick G. Ryan and Shirley W. Ryan. Shirley W. Ryan is the spouse of Patrick G. Ryan.

Patrick G. Ryan and Shirley W. Ryan are filing this Amendment No. 10 to this Schedule 13D to report the changes in their beneficial ownership of Aon Common Stock.

Item 1.	Security and Issuer
This statement relates
to the Aon Common Stock. Aon is a Delaware corporation, the principal
executive offices of which are located at 200 E. Randolph Drive, Chicago,
Illinois 60601.
Item 2.	Identity and Background
The name, business
address and present principal occupation or employment of each of the persons
filing this statement are as follows: Patrick G. Ryan : Mr. Ryan is founder,
Chairman and Chief Executive Officer of Ryan Specialty Group, a company that
provides specialty services to insurance brokers, agents and carriers. The business address of Ryan Specialty
Group, and Mr. Ryan’s business address, are 200 East Randolph St., 20 th Floor,
Chicago, Illinois 60601. Shirley W. Ryan : Mrs. Ryan is co-founder
and president of Pathways Foundation, a foundation that promotes early
detection and inclusion for infants and children with physical differences or
disabilities, and an outpatient pediatric therapy clinic. The business
address of the foundation, and Mrs. Ryan’s business address, are c/o
Ryan Enterprises Group, Suite 2100, 150 North Michigan Ave., Chicago,
Illinois 60601. Neither of the persons
filing this statement has, during the last five years, been convicted in a
criminal proceeding (excluding traffic violations or similar misdemeanors). Neither of the persons
filing this statement has, during the last five years, been a party to a
civil proceeding of a judicial or administrative body of competent
jurisdiction and as a result of such proceeding been or is subject to a
judgment, decree or final order enjoining future violations of, or
prohibiting or mandating activities subject to, Federal or State securities
laws or finding any violation with respect to such laws. Each of the persons
filing this statement is a citizen of the United States of America.
Item 3.	Source and Amount of Funds or Other
Consideration
No funds or other
consideration were borrowed or otherwise obtained for the purpose of
effecting the transactions described herein.
Item 4.	Purpose of Transaction
Patrick G. Ryan is the
retired Chairman and Chief Executive Officer of Aon. None of the persons filing this statement
has any present plans or proposals which relate to or would result in (a) the
acquisition by any person of additional securities of Aon or the disposition
of securities of Aon; (b) an extraordinary corporate transaction, such
as a merger, reorganization or liquidation, involving Aon or any of its
subsidiaries; (c) a sale or transfer of a material amount of assets of
Aon or of any of its subsidiaries; (d) any change in the present board
of directors or management of Aon, including any plans or proposals to change
the number or term of directors or to fill any existing vacancies on the
board; (e) any material change in the present capitalization or dividend
policy of Aon; (f) any other material change in Aon’s business or
corporate structure; (g) changes in Aon’s charter, bylaws or instruments
corresponding thereto or other actions which may impede the acquisition of
control of Aon by any

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CUSIP No. 200166106

| person; (h) causing a class of securities of
Aon to be delisted from a national securities exchange or to cease to be
authorized to be quoted in an inter-dealer quotation system of a registered
national securities association; (i) a class of equity securities of Aon
becoming eligible for termination of registration pursuant to Section 12(g)(4) of
the Securities Exchange Act of 1934; or (j) any action similar to any of
those enumerated above. | |
| --- | --- |
| Item 5. | Interest in Securities of the Issuer |
| The persons filing this
statement beneficially own in the aggregate (without duplication) 17,330,690
shares of Aon Common Stock, representing approximately 6.49% of the
266,851,500 issued and outstanding shares of Aon Common Stock as of January 29,
2010. The shares of Aon
Common Stock beneficially owned by such persons are beneficially owned as
follows: | |

| Patrick
G. Ryan | Sole
Power to Vote or Direct the Vote — 4,944,844 | Shared
Power to Vote or Direct the Vote — 11,801,904 | (1) | Sole
Power to Dispose or Direct the Disposition — 4,472,922 | Shared
Power to Dispose or Direct the Disposition — 12,273,826 | (2) |
| --- | --- | --- | --- | --- | --- | --- |
| Shirley
W. Ryan | 583,942 | 11,801,904 | (3) | 583,942 | 12,273,826 | (4) |

(1) Shares power to vote with Shirley W. Ryan.

(2) Shares power to dispose with Shirley W. Ryan.

(3) Shares power to vote with Patrick G. Ryan.

(4) Shares power to dispose with Patrick G. Ryan.

Since August 25, 2005, the filing persons have effected the following transactions in Aon Common Stock:

From August 25, 2005 through December 31, 2005, the filing persons sold an aggregate of 2,500,000 shares of Aon Common Stock pursuant to a written plan (the “Sales Plan”) entered into pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended, and disclosed in a prior amendment to this Schedule 13D. These sales occurred at prices ranging from $31.10 to $36.89. In addition, the filing persons donated an aggregate of 63,852 shares of Aon Common Stock to third party organizations to satisfy charitable pledges made by the filing persons to such organizations.

In 2006, the filing persons sold an aggregate of 2,500,000 shares of Aon Common Stock pursuant to the Sales Plan. These sales occurred at prices ranging from $33.23 to $40.14. In addition, the filing persons acquired an aggregate of 2,308 shares of Aon Common Stock through distributions made to Mr. Ryan based on his participation in various Aon equity incentive plans. The filing persons also donated an aggregate of 1,016,030 shares of Aon Common Stock to third party organizations to satisfy charitable pledges made by the filing persons to such organizations.

In 2007, the filing persons acquired an aggregate of 341,659 shares of Aon Common Stock through distributions made to Mr. Ryan based on his participation in various Aon equity incentive plans.

In 2008, the filing persons acquired an aggregate of 19,292 shares of Aon Common Stock through distributions made to Mr. Ryan based on his participation in various Aon equity incentive plans. In addition, the filing parties donated an aggregate of 288,360 shares to third party organizations to satisfy charitable pledges made by the filing persons to such organizations.

In 2009, the filing parties acquired an aggregate of 549,311 shares of Aon Common Stock through distributions made to Mr. Ryan based on his participation in various Aon equity incentive plans. In addition, the filing persons sold an aggregate of 446,645 shares of Aon Common Stock pursuant to open market transactions.

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CUSIP No. 200166106

These sales occurred at prices ranging from $38.62 to $41.35. The filing persons also donated an aggregate of 172,688 shares to third party organizations to satisfy charitable pledges made by the filing persons to such organizations.

From January 1, 2010 through February 25, 2010, the filing persons acquired 58,135 shares of Aon Common Stock through distributions made to Mr. Ryan based on his participation in various Aon equity incentive plans. In addition, the filing persons sold an aggregate of 811,397 shares of Aon Common Stock pursuant to open market transactions. These sales occurred at prices ranging from $39.89 to $40.48.

No transactions, other than as described above, in Aon Common Stock were effected by any of the persons filing this statement within the past sixty days.

| Item 6. | Contracts, Arrangements, Understandings or
Relationships with Respect to Securities of the Issuer |
| --- | --- |
| Patrick G. Ryan and
certain trusts for whom he or Shirley W. Ryan is a trustee have revolving and
other credit facilities with various financial institutions. Certain of
the shares of Aon Common Stock beneficially owned by the persons filing this
statement have been pledged (subject to a right to withdraw such shares from
the pledge depending on loan-to-collateral ratios) to secure repayment of
such amounts as may be outstanding under such facilities from time to
time. Additional shares of Aon Common Stock may be pledged by such
persons from time to time hereafter to secure borrowings under such
facilities or other facilities entered into in the future. | |
| Item 7. | Material to be Filed as Exhibits |
| Exhibit I
Agreement of Joint Filing, dated March 17, 2010 | |

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*SIGNATURE*

After reasonable inquiry and to the best of my knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, correct and complete.

| /s/
Patrick G. Ryan |
| --- |
| Patrick
G. Ryan |
| Dated:
March 17, 2010 |
| /s/
Shirley W. Ryan |
| Shirley
W. Ryan |
| Dated:
March 17, 2010 |

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*EXHIBIT INDEX*

Exhibit I Agreement of Joint Filing, dated March 17, 2010

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