What factor typically receives a high rating from rating agencies for insured bonds?

When considering the factors that receive high ratings from rating agencies for insured bonds, the upfront premium paid to the insurer plays a significant role. The reason this is important lies in the credit enhancement provided by the insurer. When issuers of bonds purchase insurance, they pay an upfront premium which signifies that they are protecting investors against default risk. This insurance backing increases the likelihood that bondholders will receive their scheduled payments even if the issuer encounters financial difficulties.

Rating agencies take this into account because insured bonds, with a guarantee from a reputable insurer, are considered to have a reduced risk profile. The premium reflects the insurer's assessment of the risk associated with the bond, thus assuring investors of a higher level of security and reliability. This additional layer of protection is a critical factor that enhances the perceived credit quality of the insured bonds, leading to higher ratings by rating agencies.