A method of allocating a claim covered by two or more insurance policies. Each insurer’s liability is calculated independently, and each insurer contributes in proportion to the amount of his liability as determined.

UK Version: When a claim arises, insurers contribute ‘rateably’ to the loss. The independent liability method calculates each insurer’s liability as if the other policy did not exist. The insurers then calculate their contribution to the loss in proportion to their individual liabilities, particularly in liability insurance and non-concurrent policies. Example: The policy of liability insurer A limits liability to £1 million, while the policy of liability insurer B limits liability to £0.5 million. The total loss is £200,000. Each insurer is individually liable for £200,000 and thus contributes £100,000 (50%) to the loss. Insurer B would benefit from the maximum liability (or pro rata) method, which apportions claims in proportion to indemnity limits or sums insured (2:1 in this case), implying that A would pay £100,000 and B would pay £50,000.