Ambac Financial Group, Inc. Announces Promotion of Douglas Renfield-Miller

Business Wire, July 25, 2006

NEW YORK -- Ambac Financial Group, Inc. (NYSE:ABK) today announced the promotion of Douglas Renfield-Miller to Executive Vice President. Mr. Renfield-Miller has served as Chairman and CEO of Ambac Assurance UK Limited since April 2005 and leads Ambac's European and Asia-Pacific operations out of Ambac's London office. Prior to April 2005, Mr. Renfield-Miller headed up domestic commercial asset-backed securities, structured credit and capital markets as well as having responsibility for emerging markets and the Asia-Pacific operations. Prior to joining Ambac in April 2000, Mr. Renfield-Miller was a Managing Director at UBS where he held various positions including Head of Structured Finance in the Americas and Global Head of Asset-Backed Conduits.

Commenting on the promotion, Robert J. Genader, Chairman and Chief Executive Officer, said "Since joining Ambac Doug has demonstrated strong leadership and vision and has been an integral part of our continuing growth and evolution. He has a broad array of experience in structured products, both domestic and international, representative of the franchise he has helped build over the past several years."

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, Fitch, Inc. and Rating and Investment Information, Inc. Ambac Financial Group, Inc. common stock is listed on the New York Stock Exchange (ticker symbol ABK).