S&P Gives 3-Notch Downgrade To Ambac's Key Unit

Standard & Poor's Ratings Services slapped the key operating unit of bond insurer moved Ambac Financial Group Inc. (ABK) with a three-notch downgrade due to the potential for further losses in collateralized-debt obligations.

CDOs, which use sliced-and-diced assets such as subprime mortgages to create customized products offering ...