- Additional Proxy Soliciting Materials (definitive) (DEFA14A)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934

Filed by the Registrant x Filed by a Party other than the Registrant ¨

Check the appropriate box:

Preliminary Proxy Statement

Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

Definitive Proxy Statement

Definitive Additional Materials

Soliciting Material Pursuant to §240.14a-12

Ambac Financial Group, Inc.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

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Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

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*** Exercise Your Right to Vote ***

Important Notice Regarding the Availability of Proxy Materials for the

Shareholder Meeting to Be Held on June 14, 2010


		Meeting Information
*AMBAC FINANCIAL GROUP, INC.*		Meeting Type: Annual Meeting For holders as of: April 20, 2010 Date: June 14, 2010 Time: 1:00 PM EST Location: Ambac Executive Offices One State Street Plaza New York, NY 10004

AMBAC FINANCIAL GROUP, INC. ANNE GILL KELLY ONE STATE STREET PLAZA NEW YORK, NY 10004		You are receiving this communication because you hold shares in the above named company. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting.
		See the reverse side of this notice to obtain proxy materials and voting instructions.

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—— Before You Vote ——

How to Access the Proxy Materials


Proxy Materials Available to VIEW or RECEIVE: 1. Annual Report 2. Notice & Proxy Statement How to View Online: Have the 12-Digit Control Number available (located on the following page) and visit: www.proxyvote.com . How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request:
	1	)	BY INTERNET :	www.proxyvote.com
	2	)	BY TELEPHONE :	1-800-579-1639
	3	)	BY E-MAIL* :	sendmaterial@proxyvote.com
* If requesting materials by e-mail, please send a blank e-mail with the 12-Digit Control Number (located on the following page) in the subject line. Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before May 31, 2010 to facilitate timely delivery.

—— How To Vote ——

Please Choose One of the Following Voting Methods

Vote In Person: Many shareholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the meeting you will need to request a ballot to vote these shares.

Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the 12-Digit Control Number available and follow the instructions.

Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card.

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Voting items
The Board of Directors recommends that you vote FOR the following:

1.	Election of Directors
	Nominees
01	Michael A. Callen	02	Jill M. Considine	03	Paul R. DeRosa	04	Philip N. Duff	05	Thomas C. Theobald
06	Laura S. Unger	07	Henry D. G. Wallace	08	David W. Wallis
The Board of Directors recommends you vote FOR the following proposal(s):
2.	Approve an Amendment to Ambac’s Charter to Effect a Reverse Stock Split.
3.	Approve the Tax Benefit Preservation Plan.
4.	RatifySelection of KPMG LLP, an Independent Registered Public Accounting Firm, as Independent Auditors for 2010.
NOTE: Consider any other business that is properly presented at the Annual Meeting. 0000064982_3 R2.09.05.010