Bond insurance (also known as “financial guarantee insurance”) is a type of insurance whereby an insurance company guarantees scheduled payments of interest and principal on a bond or other security in the event of a payment default by the issuer of the bond or security. As compensation for its insurance, the insurer is paid a premium (as a lump sum or in installments) by the issuer or owner of the security to be insured. Bond insurance is a form of “credit enhancement” that generally results in the rating of the insured security being the higher of the claims-paying rating of the insurer and the rating the bond would have absent insurance (also known as “underlying” or “shadow” rating).
The premium requested for insurance on a bond is a measure of the perceived risk of failure of the issuer. It can also be a function of the interest savings realized by an issuer from employing bond insurance or the increased value of the security realized by an owner who purchased bond insurance.