Liability insurance: aggregation clauses

Aggregation clauses are more or less standard in liability policies. They have two functions. First, they determine how many deductibles the assured has to bear where a series of losses arise from similar or connected events: aggregation of losses into a single deemed loss requires the application of only one deductible.

Secondly, they determine how many limits of indemnity are payable under the policy, so if there is single limit of indemnity then the assured may be held to that limit if all losses are treated as one loss. Both aspects of aggregation were considered by HHJ Waksman QC in Spire Healthcare Ltd v Royal & Sun Alliance Insurance plc [2016] EWHC 3278 (Comm).