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Exhibit 10(av)

Ninth Amendment to Aon Pension Plan
As Amended and Restated Effective January 1, 2002

        WHEREAS, the Aon Pension Plan (the "Plan") is currently set out in the
2002 Restatement of the Aon Pension Plan, which was generally effective as of
January 1, 2002 (the "Restatement").

        WHEREAS, the Board of Directors of Aon Corporation desires to amend the
Plan pursuant to the authority to do so under Section 9.01 of the Plan.

        NOW, THEREFORE, the Plan, as set out in the Restatement and as amended
from time to time, is further amended as follows:

        1.    Section 2.01.    By substituting for Section 2.01 a new
Section 2.01, effective as of January 1, 2007, to read as follows:

        "Accrued Retirement Income" shall mean the monthly amount determined in
accordance with Section 4.01 of the Plan, but based on Years of Service, Final
Average Earnings and Annual Earnings, if applicable, as of any date before the
Participant's Normal Retirement Date; provided, however, that the Accrued
Retirement Income of a Participant shall not be less than the Minimum Accrued
Benefit determined in accordance with Section 4.03.

        2.    Section 2.02.    By substituting for the last sentence of
Section 2.02 a new sentence, effective as of December 31, 2006, to read as
follows:

With respect to such Participant who has at least one Hour of Service on or
after January 1, 2002, for purposes of determining Final Average Earnings under
Section 4.01(A) (but not for purposes of determining Final Average Earnings at
December 31, 1997), the maximum amount permitted pursuant to IRC
Section 401(a)(17) shall be considered to be $200,000 for calendar years
beginning prior to January 1, 2002.

        3.    Section 2.14.    By substituting for the first paragraph of
Section 2.14 a new paragraph, effective as of December 31, 2006, to read as
follows:

        "Final Average Earnings" shall mean the average of the Participant's
Annual Earnings paid to him by the Employers for service during the highest five
consecutive calendar years of the last ten calendar years of Employment
immediately preceding the earlier of (i) his retirement date or his Termination
Date, or (ii) January 1, 2007; provided, however, that if he was not an Employee
during any five consecutive calendar years during such period, his Final Average
Earnings shall be the average of his Annual Earnings during the five calendar
years (or lesser period if he was not an Employee for such five calendar years)
immediately preceding the earlier of (i) the calendar year he was last an
Employee or (ii) January 1, 2007.

        4.    Section 2.16.    A new sentence shall be added at the end of
Section 2.16, effective as of January 1, 2006, to read as follows:

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In order to clarify the usage of the 45 Hours of Service equivalency described
above and consistent with past administrative practice and procedure under the
Plan, payroll and other Company records reflect the actual number of hours
worked by an Employee, and accordingly the 45 Hours of Service equivalency shall
not apply, where such records reflect the actual number of hours for which the
Employee is directly or indirectly paid or entitled to payment.

        5.    Section 2.19.    By substituting for Section 2.19 a new
Section 2.19, effective as of January 1, 2006, to read as follows:

        "Covered Compensation" shall mean the average of the Taxable Wage Bases
(as defined pursuant to Section 3121(a)(1) of the IRC) for the 35 calendar years
ending with the last day of the year in which a Participant attains Social
Security Retirement Age (as defined at Section 13.05(n)), and assuming for any
particular Plan Year that the Taxable Wage Base on January 1 will remain the
same for all future years.

        6.    Section 2.31.    A new subsection (i) of Section 2.31 shall be
added, effective as of January 1, 2006, to read as follows:

(i)Participants whose employment with the Company or any of its subsidiaries
shall terminate pursuant to Section 7.1 of the Renewal Rights and Asset Purchase
Agreement between Muirfield Underwriters, Ltd., a Delaware corporation, and
AmTrust North America, Inc., a Delaware corporation, dated as of May 9, 2006,
shall be credited with a Year of Service for the period commencing January 1,
2006 and ending on the date of such termination of employment regardless of
whether they complete 1,000 Hours of Service during such period.

        7.    Section 4.01.    By substituting for Section 4.01 a new
Section 4.01, effective as of December 31, 2006, to read as follows:

        4.01    Normal Retirement Benefit

        Subject to Section 4.01(C), each Participant who is employed in the
service of the Employer on his Normal Retirement Date and who retires on or
after his Normal Retirement Date shall be entitled to receive a monthly Normal
Retirement Benefit beginning on the first day of the month following his actual
retirement and continuing for his life, equal to one-twelfth of the sum of the
amounts determined under Sections 4.01(A) and 4.01(B) below.

(A)Benefit Accrual For Years of Service Completed As Of December 31, 2006.

        No Participant shall accrue any benefit under this Section 4.01(A) with
respect to Years of Service completed after December 31, 2006 or with respect to
Annual Earnings earned during the Participant's Employment after December 31,
2006. A Participant's accrued benefit under this Section 4.01(A) shall be the
sum of (a) through (e) below:

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(a)1.15% of the Participant's Final Average Earnings multiplied by his or her
Years of Service on and after January 1, 1998 and completed on or before
December 31, 2006.

(b)0.45% of the Participant's Final Average Earnings in excess of Covered
Compensation (as defined in Section 2.19) at December 31, 2006, multiplied by
the lesser of: (i) his or her Years of Service on and after January 1, 1998 and
completed on or before December 31, 2006; or (ii) 35 years, less Years of
Service as of December 31, 1997.

(c)the accrued retirement income of a Participant as of December 31, 1997, under
the terms of the Aon Pension Plan.

(i)in the case of a Participant who is employed by an Employer on December 31,
1997, and is accruing a benefit under the Aon Pension Plan on that date, the
amount described in (c) shall be multiplied by the greater of: (A) 1; or (B) a
fraction, the numerator of which is Final Average Earnings at date of
termination of employment or December 31, 2006, whichever is earlier, and the
denominator of which is Final Average Earnings at December 31, 1997.

(d)the accrued retirement income of a Participant as of December 31, 1997, under
the terms of the Pension Plan for Employees of Alexander & Alexander
Services Inc. and Subsidiaries (the "A&A Plan").

(i)in the case of a Participant who is employed by an Employer on December 31,
1997, and is accruing a benefit under the A&A Plan on that date, the amount
described in (d) shall be multiplied by the greater of: (A) 1; or (B) a
fraction, the numerator of which is Final Average Earnings (as defined under the
Aon Pension Plan) at date of termination of employment or December 31, 2006,
whichever is earlier, and the denominator of which is Final Average Earnings (as
defined under the Aon Pension Plan) at December 31, 1997.

(e)the accrued retirement income of a Participant as of December 31, 2001, under
the terms of the International Risk Management (Americas) Inc. Retirement Plan
(the "IRMG Plan").

(i)in the case of a Participant who is employed by an Employer on December 31,
2001, and is accruing a benefit under the IRMG Plan on that date, the amount
described in (e) shall be multiplied by the greater of: (A) 1; or (B) a
fraction, the numerator of which is Final Average Earnings (as

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defined under the Aon Pension Plan) at date of termination of employment or
December 31, 2006, whichever is earlier, and the denominator of which is the
Final Average Earnings (as defined under the Aon Pension Plan) at December 31,
2001.

(B)Benefit Accrual For Years of Service Completed After December 31, 2006.

        A Participant's accrued benefit under this Section 4.01(B) shall be the
aggregate amount equal to the sum for all Years of Service completed after
December 31, 2006, of the amounts determined under (a) and (b) below with
respect to each Year of Service completed after December 31, 2006:

(a)1.15% of the Participant's Annual Earnings for each Year of Service completed
after December 31, 2006; plus

(b)0.45% of the Participant's Annual Earnings for each such Year of Service in
excess of Covered Compensation (as defined in Section 2.19); provided however,
that no such excess shall be recognized for any Year of Service following the
year in which the total number of the Participant's Years of Service completed
after December 31, 2006, plus the total number (if any) of his or her Years of
Service completed as of December 31, 2006 equals 35.

For purposes of clause (b) above, in any year, if termination of employment
occurs before the fifteenth of a month, Covered Compensation shall be multiplied
by a fraction, the numerator of which is the number of full calendar months of
service completed by the Participant in the year of termination of employment
and the denominator of which is 12. If termination of employment occurs on or
after the fifteenth of a month, Covered Compensation shall be multiplied by a
fraction, the numerator of which is the number of full calendar months of
service completed by the Participant in the year of termination of employment
plus one and the denominator of which is 12.

(C)Special Provision for Participants Who Have Attained Their Normal Retirement
Date as of December 31, 2006.

        In the event that a Participant attains his Normal Retirement Date on or
before December 31, 2006, his Normal Retirement Benefit under the Plan shall not
be less than that determined under the provisions of the Plan as in effect
immediately preceding December 31, 2006.

        8.    Section 5.03.    New subsections (h) and (i) of Section 5.03 shall
be added, effective as of January 1, 2006, to read as follows:

(h)The Accrued Retirement Income of Participants whose employment with the
Company or any of its subsidiaries shall terminate pursuant to Section 7.1 of
the Renewal Rights and Asset Purchase Agreement between Muirfield
Underwriters, Ltd., a

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Delaware corporation, and AmTrust North America, Inc., a Delaware corporation,
dated as of May 9, 2006, shall be 100% vested as of the date of such termination
of employment.

(i)The Accrued Retirement Income of Participants whose employment with the
Company or any of its subsidiaries shall terminate pursuant to Section 8.2 of
the Purchase Agreement Between Aon Corporation, a Delaware corporation, and
Warrior Acquisition Corp., a Delaware corporation, dated as of June 30, 2006,
shall be 100% vested as of the date of such termination of employment.

        9.    Section 5.04.    By substituting for the reference to
"Section 4.01(c)" in clause (d) of the first sentence of Section 5.04 a new
reference to "Section 4.01," effective as of December 31, 2006.

        10.    Section 7.09.    By substituting for the first sentence of
Section 7.09 a new sentence, effective as of January 1, 2006, to read as
follows:

        In the event the actuarial equivalent of any monthly benefit pursuant to
any of the provisions of this Plan expressed as a single sum is $5,000 or less,
the Committee shall direct the Trustee, following termination of the
Participant's employment and as soon as administratively feasible thereafter, to
pay to the person entitled to such monthly benefit, in a single sum, the amount
of such actuarial equivalent.

        11.    Section 18.01.    A new sentence shall be added at the end of
Section 18.01, effective December 31, 2006, to read as follows:

References in this Section 18 to Section 4.01 of the Plan or to any subsection
of Section 4.01 of the Plan shall mean and refer to such Section, and
subsections thereof, as in effect immediately prior to January 1, 1998, except
as otherwise clearly indicated from the text.

        12.    Section 18.11.    By substituting for the reference to
"Section 4.01(e)" in subsection (f) of Section 18.11 a new reference to
"clause (e) of the second sentence of Section 4.01(A)," effective as of
December 31, 2006.

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Ninth Amendment to Aon Pension Plan As Amended and Restated Effective January 1,
2002