Press Release

Ambac Named 2007 Monoline of the Year by ISR

NEW YORK, December 13, 2007-- Ambac Financial Group, Inc. (NYSE: ABK) (Ambac) announced today that International Securitisation Report (ISR) has named Ambac Monoline Insurer of the Year. The award is based on Ambac's strong global presence and its role in a number of ground-breaking transactions in 2007, as well as from the results of ISR's online poll.

“Ambac is honored to receive this award,” said Douglas Renfield-Miller, Executive Vice President of Ambac and Chairman of Ambac UK Limited. “Ambac has had an active year closing many noteworthy transactions. This award underscores the company's ability to use our in-depth knowledge and expertise to help issuers and financial advisors structure innovative transactions across a diverse range of asset classes and jurisdictions.”

In 2007, Ambac was sole guarantor of award-winning deals Theatre Hospitals 1&2 (CMBS Deal of the Year - Europe) and Punch Taverns Finance (Corporate Deal of the Year - Europe). It also participated in Channel Link Enterprises Finance (Deal of the Year - Europe) and Airspeed (ABS Deal of the Year - Europe).

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Ambac Financial Group, Inc., headquartered in New York City , is a holding company whose affiliates provide financial guarantees and financial services to clients in both the public and private sectors around the world. Ambac's principal operating subsidiary, Ambac Assurance Corporation, a leading guarantor of public finance and structured finance obligations, has earned triple-A ratings, the highest ratings available from Moody's Investors Service, Inc., Standard & Poor's Ratings Services and Fitch, Inc. Ambac Financial Group, Inc. common stock is listed on the New York Stock Exchange (ticker symbol ABK).