THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR THE
SECURITIES LAWS OF ANY STATE AND MAY NOT BE SOLD OR TRANSFERRED IN THE ABSENCE
OF SUCH REGISTRATION OR AN EXEMPTION THEREFROM UNDER SAID ACT AND APPLICABLE
STATE SECURITIES LAWS.
 
UNSECURED SENIOR PROMISSORY NOTE DUE November 30, 2007
 
$600,000
November 30, 2006

 
FOR VALUE RECEIVED, Aston Asset Management LLC, a Delaware limited liability
company (the “Debtor”), hereby promises to pay to the order of Highbury
Financial Inc., a Delaware corporation (the “Payee”), the principal amount of
Six Hundred Thousand Dollars ($600,000) (the “Principal”), together with
interest thereon calculated from the date hereof in accordance with the
provisions of this Note. Capitalized terms used but not otherwise defined herein
shall have the meaning ascribed to such term in the Aston Asset Management LLC
Amended and Restated Limited Liability Company Agreement, dated as of April 20,
2006 (the “LLC Agreement”).
 
1.  Due Date. The Principal (plus interest as provided in the following section)
shall be repaid by Debtor on November 30, 2007.
 
2.  Interest. Interest shall accrue per annum at a rate equal to the prime
lending rate then in effect as reported by JPMorgan Chase on the unpaid
Principal amount of this Note outstanding from time to time. Interest shall be
computed on the basis of the actual number of days elapsed and a 365-day year.
 
3.  Mandatory Prepayment. The Principal, and accrued interest thereon, of this
Note shall be prepaid from all monies allocated as Owners’ Allocation that is
payable to the Non-Manager Members and all monies allocated as Operating
Allocation prior to any distributions by the Debtor to the Non-Manager Members.
Any such prepayment shall be first applied to the Payment of any accrued
interest and then to the unpaid balance of the Principal.
 
4.  Method of Payments.
 
(a)  Place of Payment, etc. Payments of Principal and interest becoming due and
payable under this Note shall be made at the Payee’s office at 999 Eighteenth
Street, Suite 3000, Denver, Colorado 80202 or at such place as the Payee may
notify the Debtor in writing from time to time. All amounts due under this Note
shall be paid in lawful money of the United States of America.
 
(b)  Application of Payments. Any payment under this Note shall be applied first
to sums due under this Note other than Principal and interest, second to accrued
interest and third to any Principal amount outstanding under this Note.
 

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(c)  Payments Due on Non-Business Days. If payment of Principal or interest on
this Note becomes due on a day which is not a Business Day, such payment will be
made on the next succeeding Business Day and such extension of time will in such
case be included in computing interest in connection with such payment. A
“Business Day” shall mean any weekday on which banking institutions in New York,
New York and Denver, Colorado are open for the transaction of banking business.
 
5.  Events of Default.
 
(a)  The term “Event of Default” means any of the following events:
 
(i)  any payment of Principal or interest is not paid when due pursuant to
Section 1 and Section 3 and such default shall have continued for a period of
five (5) days after the Debtor receives written notice thereof;
 
(ii)  the Debtor (x) makes an assignment for the benefit of creditors, (y)
admits in writing its inability to pay or fails to pay its debts generally as
they come due or (z) files a petition for relief under any chapter of the United
States Federal Bankruptcy Code or any other bankruptcy or debtor relief law,
domestic or foreign, as now or hereafter in effect, or seeking the appointment
of a trustee, receiver, custodian, liquidator or similar official for it or any
of its property; or any such action is commenced against it and it admits,
acquiesces in or does not contest diligently the material allegations thereof,
or the action results in an entry of an order for relief against it, or it does
not obtain permanent dismissal and discharge thereof before the earlier of trial
thereon or 60 days after commencement of the action; or
 
(iii)  a breach of the covenants contained in Section 6 below.
 
(b)  Remedies Upon Default. Upon the occurrence of an Event of Default, the
entire unpaid balance of the principal, together with all accrued but unpaid
interest thereon, shall become immediately due and payable, in addition to all
reasonable legal fees and expenses incurred by Payee in connection with the
collection of this Note (which legal fees and expenses shall be paid by Debtor).
 
6.  Indebtedness. Debtor shall not incur, create, assume, or become liable in
any manner, or permit to exist, any indebtedness unless:
 
(i)  such indebtedness is permitted under the terms of the LLC Agreement;
 
(ii)  is properly legended and designated as subordinated to the Note; and
 
(iii)  is not secured by any assets of the Debtor.
 

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7.  Amendment and Waiver. The provisions of this Note may not be modified or
amended, except by an instrument in writing executed by the parties hereto. This
Note shall bind the respective heirs, personal representatives, successors and
assigns of the Debtor, and shall inure to the benefit of Payee, its successors
and assigns. No waiver or consent by Payee with respect to this Note shall be
valid and binding unless in writing and executed by the Payee, and any such
waiver or consent which may be granted by Payee shall be effective only within
the limitations stated in such waiver and only for the particular event for
which such waiver is given.
 
8.  Cancellation. After all Principal of, and accrued interest at any time owed
on, this Note have been paid in full, this Note will be surrendered to the
Debtor for cancellation and will not be reissued.
 
9.  Governing Law. This Note shall be governed by and construed in accordance
with the domestic laws of the State of New York, without giving effect to any
choice of law or conflict of law provision or rule (whether of the State of New
York or any other jurisdiction) that would cause the application of the laws of
any jurisdiction other than the State of New York.
 
10.  Waiver of Jury Trial. The parties hereto waive their right to a trial by
jury for any claims arising out of or related to this Note.
 
11.  Further Assurances. Debtor shall, from time to time, execute, acknowledge
and deliver, or cause to be executed, acknowledged and delivered, such
supplements hereto and such further instruments as may reasonably be required
for carrying out the intention of or facilitating the performance of this Note.
 

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IN WITNESS WHEREOF, the Debtor has executed and delivered this Note on the date
first written above.
 

       
ASTON ASSET MANAGEMENT LLC
 
   
   
    By:   /s/ Stuart D. Bilton   

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Stuart D. Bilton   Chairman and Chief Executive Officer 

           
   
   
    By:   /s/ Richard S. Foote  

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Richard S. Foote  
President and Chief Executive Officer,
Highbury Financial Inc., as manager member
of Aston Asset Management LLC

 

HIGHBURY FINANCIAL INC.                           By: /s/ R. Bradley Forth      
 

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R. Bradley Forth      
Executive Vice President
     

 

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