Aviva and RSA are among the insurers facing a multi-million pound hit following the BBC's Jimmy Savile sex abuse scandal.
The FTSE 100 insurers have emerged as underwriters of policies taken out by the broadcaster to protect it against legal claims between 1971 and 2006, when Savile carried out a series of sex attacks.
Information obtained by insurance trade magazine Post reveals that the group of insurers could face sexual abuse claims of up to £30m. The police Operation Yewtree, which is looking into allegations of sex crimes against the former DJ and a host of other celebrities, has so far recorded 450 complaints against the late Savile.
It is believed that Savile could have sexually abused treble the number of victims who have come forward so far. A report released earlier this year revealed the disgraced TV presenter was one of the UK's "most prolific known sexual predators" and said his victims included an eight-year-old boy and a seriously ill teenager.
The report by Scotland Yard and the NSPCC, released in January, found that Savile's reign of sexual abuse spanned 54 years.
An RSA spokeswoman said: "At various points over the past 40 years we have provided insurance for the BBC. We are unable to comment as to whether these policies will respond to any Savile claims."
However, a spokesman for Allianz, which has also provided insurance to the BBC, said: "Some years ago we provided employers liability insurance to the BBC. But we believe that the incidents described are more likely to be associated with the cover provided by public liability insurance."
Aviva declined to comment.