Obligation AON 5% ( US037389AW39 ) en USD

AON

100.65 % ⇌

Etats-unis

US037389AW39 ( en USD )

5% par an ( paiement semestriel )

29/09/2020 - Obligation échue

Prospectus brochure de l'obligation AON US037389AW39 en USD 5%, échue

1 000 USD

600 000 000 USD

037389AW3

N/A

L'Obligation émise par AON ( Etats-unis ) , en USD, avec le code ISIN US037389AW39, paye un coupon de 5% par an.
Le paiement des coupons est semestriel et la maturité de l'Obligation est le 29/09/2020
L'Obligation émise par AON ( Etats-unis ) , en USD, avec le code ISIN US037389AW39, a été notée NR par l'agence de notation Standard & Poor's ( S&P ).

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424B5 1 d424b5.htm PROSPECTUS SUPPLEMENT
Table of Contents
Filed Pursuant to Rule 424(b)(5)
Registration No. 333-159841
CALCULATION OF REGISTRATION FEE

Maximum
Maximum
Title of Each Class of
Amount to be
Offering Price
Aggregate
Amount of
Securities to be Registered
Registered
Per Unit
Offering Price
Registration Fee(1)
3.50% Senior Notes due 2015
$600,000,000
99.517%
$597,102,000
$42,573.37
5.00% Senior Notes due 2020
$600,000,000
99.637%
$597,822,000
$42,624.71
6.25% Senior Notes due 2040
$300,000,000
99.084%
$297,252,000
$21,194.07
(1) Calculated in accordance with Rule 457(r) under the Securities Act of 1933 (the "Securities Act"). Total registration fee
is $106,392.15.
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Prospectus Supplement
(To Prospectus Dated June 8, 2009)
$1,500,000,000

Aon Corporation
$600,000,000 3.50% Senior Notes due 2015
$600,000,000 5.00% Senior Notes due 2020
$300,000,000 6.25% Senior Notes due 2040
We are offering $600,000,000 aggregate principal amount of our 3.50% senior notes due 2015 (the "2015 Notes"),
$600,000,000 aggregate principal amount of our 5.00% senior notes due 2020 (the "2020 Notes") and
$300,000,000 aggregate principal amount of our 6.25% senior notes due 2040 (the "2040 Notes"). The 2015 Notes, the 2020
Notes and the 2040 Notes are collectively referred to herein as the "Notes."
The 2015 Notes will mature on September 30, 2015, the 2020 Notes will mature on September 30, 2020 and the 2040
Notes will mature on September 30, 2040. We will pay interest on the Notes of each series on each March 30 and September
30, commencing on March 30, 2011.
We may redeem the Notes of any series at any time, and from time to time, by paying to the holders thereof 100% of the
principal amount plus a make-whole redemption premium as described in this prospectus supplement under "Description of
the Notes--Optional Redemption." If a Change of Control Repurchase Event occurs as described in this prospectus
supplement under "Description of the Notes--Change of Control Repurchase Event," we will be required to offer to purchase
all of the Notes from the holders at a price equal to 101% of the principal amount thereof.
The Notes are being offered to finance in part our merger with Hewitt Associates, Inc. ("Hewitt"). Upon consummation
of the offering of the Notes, we will deposit the net proceeds from this offering into escrow as described in "Description of
the Notes--Escrow of Proceeds; Special Mandatory Redemption." If the merger with Hewitt does not occur on or prior to
March 31, 2011, or if the Merger Agreement is terminated at any time prior thereto, we will be required to redeem all of the
Notes offered hereby at a redemption price equal to 101% of the aggregate principal amount of the Notes, plus accrued and
unpaid interest from the date of initial issuance, or the most recent date to which interest has been paid or duly provided for,
as the case may be, to but excluding the Special Mandatory Redemption Date. See "Use of Proceeds" and "Description of the
Notes--Escrow of Proceeds; Special Mandatory Redemption."
The Notes will be unsecured and will rank senior to all our existing and future subordinated debt and will rank equally in
right of payment with our existing and future unsecured senior debt. The Notes will not have the benefit of all of the
covenants applicable to some of our existing unsecured senior debt. The Notes will be effectively subordinated to any
secured debt we may have or incur in the future. The Notes will be structurally subordinated to the debt and all other
obligations of our subsidiaries.
Investing in the Notes involves a high degree of risk. See "Risk Factors" beginning on page S-14 of this
prospectus supplement.
Neither the Securities and Exchange Commission nor any state securities commission has approved or
disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is
truthful or complete. Any representation to the contrary is a criminal offense.

Per 2015
Per 2020
Per 2040

Note
Note
Note

Total
Public offering price

99.517%
99.637%
99.084%
$1,492,176,000
Underwriting discount

0.500%
0.550%
0.875%
$
8,925,000
Proceeds to us (before expenses)

99.017%
99.087%
98.209%
$1,483,251,000
Interest on the Notes will accrue from September 10, 2010.
The Notes will not be listed on any securities exchange. Currently, there are no public markets for the Notes.
The underwriters expect to deliver the Notes for purchase on or about September 10, 2010, in book-entry form through
the facilities of The Depository Trust Company and its participants, including Clearstream Banking, société anonyme, and
Euroclear Bank S.A./N.V.

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Joint Book-Running Managers

Credit Suisse

Morgan Stanley
BofA Merrill Lynch
Deutsche Bank Securities

RBS

Co-Managers

Aon Benfield Securities, Inc.

ANZ Securities

Loop Capital Markets
RBC Capital Markets

UBS Investment Bank

Wells Fargo Securities

The date of this prospectus supplement is September 7, 2010.
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TABLE OF CONTENTS
Prospectus Supplement

Page
About This Prospectus Supplement

S-1
Where You Can Find More Information

S-1
Disclosure Regarding Forward-Looking Statements

S-2
Summary

S-4
Risk Factors
S-14
Use of Proceeds
S-24
Ratio of Earnings to Fixed Charges
S-25
Capitalization
S-26
Aon Corporation and Hewitt Associates, Inc. Unaudited Pro Forma Condensed Combined Financial Statements
S-27
Description of the Notes
S-42
Certain United States Federal Income Tax Consequences
S-48
Book-Entry, Delivery and Form
S-52
Underwriting (including Conflicts of Interest; Other Relationships)
S-56
Incorporation of Certain Documents by Reference
S-60
Legal Matters
S-60
Experts
S-60
Prospectus

Page
About This Prospectus

3
Where You Can Find More Information

3
Information Concerning Forward-Looking Statements

4
Risk Factors

5
The Company

5
Use of Proceeds

6
Ratios

6
Description of Debt Securities

6
Description of Preferred Stock and Common Stock

16
Description of the Share Purchase Contracts and the Share Purchase Units

18
Description of Guarantees

18
Plan of Distribution

18
Validity of Securities

20
Experts

20
We have not authorized anyone to provide any information other than that contained or incorporated by
reference in this prospectus supplement, the accompanying prospectus or in any free writing prospectus prepared by
or on behalf of us or to which we have referred you. We take no responsibility for, and can provide no assurance as to
the reliability of, any other information that others may give you. The information appearing or incorporated by
reference in this prospectus supplement and the accompanying prospectus is accurate as of the date of the document
in which the information appears. Our business, financial condition, results of operations and prospects may have
changed since the date of the relevant document. Neither the delivery of this prospectus supplement and the
accompanying prospectus nor any sale made hereunder shall under any circumstance imply that the information in or
incorporated by reference in this prospectus supplement or the accompanying prospectus is correct as of any date
subsequent to the date of the document in which the information appears.

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ABOUT THIS PROSPECTUS SUPPLEMENT
This document consists of two parts. The first part is this prospectus supplement, which describes the specific terms of
this offering. The second part is the accompanying prospectus, which describes more general information, some of which
may not apply to this offering. You should read both this prospectus supplement and the accompanying prospectus, together
with the documents incorporated by reference and the additional information described below under the heading "Where You
Can Find More Information."
If the description of this offering varies between this prospectus supplement and the accompanying prospectus, you
should rely on the information in this prospectus supplement.
Any statement made in this prospectus supplement or in a document incorporated or deemed to be incorporated by
reference in this prospectus supplement will be deemed to be modified or superseded for purposes of this prospectus
supplement to the extent that a statement contained in this prospectus supplement or in any other subsequently filed
document that is also incorporated or deemed to be incorporated by reference in this prospectus supplement modifies or
supersedes that statement. Except as so modified or superseded, any statement so modified or superseded will not be deemed
to constitute a part of this prospectus supplement. See "Incorporation of Certain Documents by Reference" in this prospectus
supplement.
In this prospectus supplement, except as otherwise indicated herein, references to "Aon," the "Company," "we," "us" or
"our" refer to Aon Corporation and its subsidiaries and, in the context of the Notes, "Aon," the "Company," "we," "us" and
"our" shall only refer to Aon Corporation, the issuer of the Notes.
WHERE YOU CAN FIND MORE INFORMATION
We are subject to the information reporting requirements of the Securities Exchange Act of 1934, as amended (the
"Exchange Act"). In accordance with the Exchange Act, we file annual, quarterly and current reports, proxy statements and
other information with the Securities and Exchange Commission (the "SEC"). Our SEC file number is 001-07933. You can
read and copy this information at the following location of the SEC:
Public Reference Room
100 F Street, N.E.
Room 1850
Washington, D.C. 20549
You can also obtain copies of these materials from this public reference room, at prescribed rates. Please call the SEC at
1-800-SEC-0330 for further information on its public reference room. The SEC also maintains a web site that contains
reports, proxy statements and other information about issuers, like us, who file electronically with the SEC. The address of
that site is www.sec.gov.
This prospectus supplement and the accompanying prospectus, which form a part of the registration statement, do not
contain all the information that is included in the registration statement. You will find additional information about us in the
registration statement. Any statements made in this prospectus supplement, the accompanying prospectus or any documents
incorporated by reference herein or the accompanying prospectus concerning the provisions of legal documents are not
necessarily complete and you should read the documents that are filed as exhibits to the registration statement or otherwise
filed with the SEC for a more complete understanding of the document or matter.

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DISCLOSURE REGARDING FORWARD-LOOKING STATEMENTS
This prospectus supplement, the accompanying prospectus and any documents incorporated by reference into this
prospectus supplement or the accompanying prospectus contain certain statements related to future results, or states our
intentions, beliefs and expectations or predictions for the future which are forward-looking statements as that term is defined
in the Private Securities Litigation Reform Act of 1995. Forward-looking statements relate to expectations or forecasts of
future events. They use words such as "anticipate," "believe," "estimate," "expect," "forecast," "project," "intend," "plan,"
"potential," and other similar terms, and future or conditional tense verbs like "could," "may," "might," "should," "will" and
"would." You can also identify forward-looking statements by the fact that they do not relate strictly to historical or current
facts. For example, we may use forward-looking statements when addressing topics such as: market and industry conditions,
including competitive and pricing trends; changes in our business strategies and methods of generating revenue; the
development and performance of our services and products; changes in the composition or level of our revenues; our cost
structure and the outcome of cost-saving or restructuring initiatives; the outcome of contingencies; dividend policy; the
expected impact of acquisitions and dispositions; pension obligations; cash flow and liquidity; future actions by regulators;
and the impact of changes in accounting rules. These forward-looking statements are subject to certain risks and uncertainties
that could cause actual results to differ materially from either historical or anticipated results depending on a variety of
factors. Potential factors that could impact results include:

· changes in global equity and fixed income markets that could affect the return on invested assets;

· fluctuations in exchange and interest rates that could impact revenue and expense;

· rating agency actions that could affect our ability to borrow funds;

· changes in the funding status of our various defined benefit pension plans and the impact of any increased pension

funding resulting from those changes;

· changes in the competitive environment;

· the impact on risk and insurance services commission revenues of changes in the availability of, and the premium

insurance carriers charge for, insurance and reinsurance products, including the impact on premium rates and
market capacity attributable to catastrophic events;

· the outcome of inquiries from regulators and investigations related to compliance with the U.S. Foreign Corrupt

Practices Act and non-U.S. anti-corruption laws;

· the impact of investigations brought by U.S. state attorneys general, U.S. state insurance regulators, U.S. federal

prosecutors, U.S. federal regulators, and regulatory authorities in the U.K. and other countries;

· the impact of class actions and individual lawsuits including client class actions, securities class actions, derivative

actions and ERISA class actions;

· the cost of resolution of other contingent liabilities and loss contingencies, including potential liabilities arising

from errors and omissions claims;

· the ability to realize the anticipated benefits to us of our merger with Benfield Group Limited ("Benfield");

· the possibility that the expected efficiencies and cost savings from the proposed transaction with Hewitt will not be

realized, or will not be realized within the expected time period;

· the ability to obtain governmental approvals of the Hewitt merger on the proposed terms and schedule

contemplated by the parties;

· the failure of stockholders of Hewitt to approve the proposal to adopt the Merger Agreement (as defined herein);

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· the failure of the stockholders of Aon to approve the issuance of Aon common stock to Hewitt stockholders in the

merger;

· the risk that the Aon and Hewitt businesses will not be integrated successfully;

· disruption from the proposed Hewitt transaction making it more difficult to maintain business and operational

relationships with customers, partners and others;

· the possibility that the proposed Hewitt transaction does not close, including, but not limited to, due to the failure to

satisfy the closing conditions;

· general economic conditions in different countries in which Aon and Hewitt do business around the world;

· the loss of key Aon or Hewitt employees following the merger;

· the extent to which Aon and Hewitt retain existing clients and attract new businesses;

· the extent to which Aon and Hewitt manage certain risks created in connection with the various services, including

fiduciary and advisory services, among others, that Aon and Hewitt currently provide, or will provide in the future,
to clients;

· the ability to implement restructuring initiatives and other initiatives intended to yield cost savings, and the ability

to achieve those cost savings; and

· the impact of, and potential challenges in complying with, legislation and regulation in the jurisdictions in which

Aon and Hewitt operate, particularly given the global scope of Aon's and Hewitt's businesses and the possibility of
conflicting regulatory requirements across jurisdictions in which Aon and Hewitt do business.
Any or all of our forward-looking statements may turn out to be inaccurate, and there are no guarantees about our
performance. The factors identified above are not exhaustive. Aon and its subsidiaries operate in a dynamic business
environment in which new risks may emerge frequently. Accordingly, you should not place undue reliance on forward-
looking statements, which speak only as of the dates on which they are made. We are under no obligation (and expressly
disclaim any obligation) to update or alter any forward-looking statement that we may make from time to time, whether as a
result of new information, future events or otherwise. Further information about factors that could materially affect Aon,
including our results of operations and financial condition and our potential merger with of Hewitt, is contained in the "Risk
Factors" section in this prospectus supplement and in the "Risk Factors" section, the "Legal Proceedings" section, the
"Management's Discussion and Analysis of Financial Condition and Results of Operations" section and other sections of our
Annual Report on Form 10-K for the year ended December 31, 2009 and Quarterly Reports on Form 10-Q for the quarters
ended March 31, 2010 and June 30, 2010, in each case as filed with the SEC. Further information about information that
could materially affect Hewitt is contained in the "Risk Factors" section, the "Legal Proceedings" section, the
"Management's Discussion and Analysis of Financial Condition and Results of Operations" section and other sections of
Hewitt's Annual Report on Form 10-K for the year ended September 30, 2009 and Quarterly Reports on Form 10-Q for the
quarters ended December 31, 2009, March 31, 2010 and June 30, 2010, in each case as filed with the SEC.

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SUMMARY
This summary highlights certain information about us and the offering of the Notes. This summary does not contain
all the information that may be important to you. You should carefully read this entire prospectus supplement, the
accompanying prospectus and those documents incorporated by reference into this prospectus supplement and the
accompanying prospectus, including the risk factors and the financial statements and related Notes, before making an
investment decision.
Aon Corporation
Overview
Aon Corporation provides risk management and human capital consulting services, delivering distinctive client
value via innovative and effective risk management solutions, including insurance and reinsurance brokerage and
workforce productivity solutions. Aon's technical expertise is delivered locally through colleagues worldwide.
We serve clients through the following businesses:

· Risk and Insurance Brokerage Services acts as an advisor and insurance broker, helping clients manage their

risks, as well as negotiating and placing insurance risk with insurance carriers through our global distribution
network.

· Consulting provides advice and services to clients related to health and benefits, retirement, compensation,

strategic human capital, and human resource outsourcing.
Our clients include corporations and businesses, insurance companies, professional organizations, independent
agents and brokers, governments, and other entities. We also serve individuals through personal lines, affinity groups,
and certain specialty operations.
Aon was incorporated in 1979 under the laws of Delaware, and is the parent corporation of both long-established
and acquired companies. As of December 31, 2009, we had approximately 36,200 employees and conduct our operations
through various subsidiaries in more than 120 countries and sovereignties.
Pending Merger with Hewitt
On July 11, 2010, we, Alps Merger Corp. ("Merger Sub"), a wholly owned subsidiary of ours, Alps Merger LLC
("Merger LLC"), a wholly owned subsidiary of ours, and Hewitt entered into an Agreement and Plan of Merger (the
"Merger Agreement"), which is incorporated herein by reference to our Current Report on Form 8-K filed with the SEC
on July 12, 2010, providing for the merger of Hewitt with Aon, which we sometimes refer to as the "transaction."
Subject to the terms and conditions of the Merger Agreement, which has been approved by the board of directors of each
of the parties, Merger Sub will be merged with and into Hewitt, with Hewitt continuing as the surviving corporation and
a wholly owned subsidiary of Aon, which we sometimes refer to as the "merger." Immediately following completion of
the merger, Hewitt would merge with and into Merger LLC, with Merger LLC surviving the subsequent merger as a
wholly owned subsidiary of Aon. There can be no assurance that the merger will be completed.
If the merger is consummated, each share of Class A common stock of Hewitt outstanding immediately prior to the
effective time would convert into, at the election of each of the holders of Hewitt common stock, (i) 0.6362 of a share of
common stock of Aon and $25.61 in cash, (ii) an amount of cash (rounded to two decimal places), without interest, equal
to the sum of (a) $25.61 and (b) the product obtained by multiplying 0.6362 by

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the closing volume-weighted average price of Aon common stock, rounded to four decimal points, on the NYSE for the
period of ten consecutive trading days ending on the second full trading day prior to the effective time of the merger
(calculated as (1) the sum of (A) the share price of each trade of common stock during the ten trading day period
multiplied by (B) the number of shares of Aon common stock traded in such trade, divided by (2) the total number of
shares of Aon common stock traded during the ten day trading period), which price we refer to as the closing Aon
VWAP, or (iii) a number of shares of Aon common stock equal to the sum of (a) 0.6362 and (b) the quotient (rounded to
four decimal places) obtained by dividing $25.61 by the closing Aon VWAP. The consideration to be paid to holders of
Hewitt common stock electing to receive the cash consideration or the stock consideration described above in connection
with the merger is subject, pursuant to the terms of the Merger Agreement, to automatic proration and adjustment, as
applicable, to ensure that the amount of cash paid and the number of shares of Aon common stock issued by Aon in the
merger each represents approximately 50% of the aggregate merger consideration (taking into account the roll-over of
Hewitt stock options into options exercisable for Aon common stock).
Hewitt is a leading global provider of human resources outsourcing and consulting services. Hewitt helps its clients
generate greater value from their investment in their people by helping them solve their most complex human resources,
benefit and related financial challenges. Founded in 1940, Hewitt began as a provider of actuarial services for sponsors
of retirement plans and executive compensation consulting services. Over the last seven decades, Hewitt expanded to
provide a full range of human capital services that anticipate its clients' changing business needs.
Hewitt's total revenues and net income for its fiscal year ended September 30, 2009 were $3.1 billion and $265
million, respectively and for the nine months ended June 30, 2010 were $2.3 billion and $204 million,
respectively. Hewitt's common stock is listed on the New York Stock Exchange. Hewitt files reports and other
information with the New York Stock Exchange and the SEC.
As described below under "--Aon Corporation--Merger Agreement," the consummation of the merger is subject to
certain conditions, including, among others, the adoption of the Merger Agreement by Hewitt's stockholders and the
approval of the issuance of our common stock by our stockholders.
Transaction Rationale
In determining to pursue the merger with Hewitt, our board of directors considered, among other things, the
following factors relating to the merger:

· the areas of risk and human capital are becoming increasingly linked and our combination with Hewitt would

create the world's preeminent provider of risk and human capital solutions, with the ability to offer enhanced
and diverse services and solutions to Aon and Hewitt clients across all market segments;

· the combined Aon Hewitt business would represent a leading global brand with revenues of approximately

$4.3 billion and would supplement Aon's existing number one ranking in terms of revenues as an advisor in the
areas of primary insurance brokerage, reinsurance brokerage and captive management;

· the combined Aon Hewitt business is expected to have a number one ranking in revenues in the areas of

benefits administration and Human Resource Business Process Outsourcing ("HR BPO"), as well as allow Aon
to assume a leading market position in human resources consulting;

· Aon and Hewitt share a complementary product portfolio across the benefits administration and consulting
businesses, which would offer significant cross-selling opportunities within the combined Aon Hewitt business,

allowing Aon to offer certain products to Hewitt's predominantly large corporate client base and allowing
Hewitt to offer certain products to Aon's predominantly middle market client base;

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· the combination would facilitate cross-selling across segments, including the marketing of Hewitt's benefits

outsourcing and HR BPO services to Aon's existing clients, as well as the marketing of Aon's risk services
product portfolio to Hewitt's existing clients;

· the combined Aon and Hewitt client base in the human capital solutions area would create a diversified

geographic presence that would likely provide additional cross-selling opportunities;

· though no particular level of cost synergies could be assured, the combination is estimated to yield significant

potential cost synergies in the principal areas of consolidated corporate governance, reduced public company
costs, reduced labor and shared platform costs of approximately $355 million on an annual basis in 2013;

· the similar management styles and comparable corporate cultures of the two companies would allow the

companies to easily and quickly integrate their operations; and

· Aon's history and experience in integrating businesses in prior significant transactions, including the

acquisition of Benfield in 2008.
For the discussion of various factors that could prohibit or limit us from realizing some or all of these benefits, see
the discussion in this prospectus supplement under "Risk Factors."
Merger Agreement
Conditions
The Merger Agreement provides that the consummation of the merger with Hewitt is subject to certain conditions,
including, among others, the adoption of the Merger Agreement by Hewitt's stockholders, the approval of the issuance of
common stock in the merger by our stockholders, the expiration or earlier termination of the applicable waiting period
under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (the "HSR Act"), which expiration occurred on
August 23, 2010, and the receipt of other material antitrust approvals as described below under "--Aon Corporation--
Merger Agreement--Governmental Approvals." The meeting of Hewitt's stockholders to vote on the merger is currently
scheduled to take place on September 20, 2010. The meeting of our stockholders to approve the issuance of common
stock in the merger is currently scheduled to take place on September 20, 2010. There can be no assurance as to whether
or, if so, when the conditions to consummation of the merger will be satisfied.
Covenants
The Merger Agreement contains customary covenants, including covenants providing for no solicitation of alternate
transactions by Hewitt and for each of the parties to use reasonable best efforts to cause the transaction to be
consummated.
Governmental Approvals
Aon and Hewitt have each agreed to use their respective reasonable best efforts to obtain all governmental and
regulatory approvals required to complete the transactions contemplated by the Merger Agreement. These approvals
include approval under, or the expiration or termination of waiting periods pursuant to, the HSR Act, the EC Merger
Regulation (Regulation 139 of 2004), the Investment Canada Act, the Competition Act (Canada) and other applicable
regulatory laws. The waiting period under the HSR Act expired on August 23, 2010, and Aon received a "no action"
letter from Canada's Competition Bureau on September 7, 2010.
Termination
The Merger Agreement contains certain termination rights for both Aon and Hewitt. If the Merger Agreement is
terminated, Hewitt may be required in certain specified circumstances to pay a termination fee of $190 million to Aon. If
the Merger Agreement is terminated under certain other specified circumstances, Aon

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