Aviva is refusing to pay £217,481 damages to a mother who lost her seamstress daughter to asbestos-related cancer, a High Court writ claims.
However, the insurer says it has been unable to uncover any information that it held employers' liability insurance for textile company FW Harmer and Co Ltd.
Doreen Browne is seeking damages after her daughter, Linda Pyke, 56, died in 2003 from mesothelioma after working at FW Harmer.
Browne, 85, wants Aviva to pay £160,916 damages awarded at Norwich County Court on 20 June last year, plus £43,855.98 legal costs.
An Aviva spokesman said: "We operate under an agreed code of practice to identify any policy documents that exist for employers' liability insurance, where the insured company has either ceased trading or lost documents.