MBIA INSURANCE CORPORATION
A division of publicly traded Municipal Bond Insurance Association, Inc. that primarily issues financial guarantee worldwide. It used to back municipal bonds and structured finance products. This insurance company serves as an avenue to credit enhancement, as the corporation will take care of the interest and principal on any bond that is suffering from an issuer default.
Having an MBIA insurance on a municipal bond usually ensures an AAA rating or equivalent to major ratings agencies, thus making the bonds more marketable to investors.