A court has ruled that indemnity insurers must pay a claim by Bank of Queensland, after finding that a class action is a single claim and not multiple claims.BOQ paid A$6 million last year to settle a class action brought by Petersen Superannuation Fund Pty Ltd on behalf of itself and other investors.The claim was for losses incurred when they invested in a scheme conducted by Sherwin Financial Planners, which utilised BOQ accounts. The scheme turned out to be a fraud and the claim against the bank was that it failed to protect the investors' interests when it became aware of the fraud.After the class action was settled BOQ went to court seeking a declaration that it was entitled to indemnity from three insurers, including AIG Australia Ltd and Catlin Australia. The policy had a $40 million limit of liability and a retention of $2 million for each claim.When the case first went to court in November last year, the insurers were successful in arguing that that BOQ's loss arose from multiple claims in relation to each of which the $2 million retention applied.BOQ took the case to the appeals division of the New South Wales Supreme Court, which set aside the decision of the primary judge and ruled that the settlement of the class action "was the settlement of a single claim" within the meaning of the insurance policy and that the loss suffered by BOQ was a loss resulting from a single claim.The court said: "A reasonable businessperson would, taking each investor separately, consider that the representative processing was a 'suit of proceeding' brought by that investor within the meaning of the policy."It was a 'suit of proceeding' brought by Petersen on behalf of the investors, rather than a 'suit of proceeding' brought by the investors."The court said the multiple claims arose out of one or a series of related wrongful acts and should therefore be aggregated, with the result that only one retention was applicable.