Males LJ in Equitas Insurance Ltd v Municipal Mutual Insurance Ltd

Where a reinsured under successive excess of loss reinsurances has suffered losses (here employers' liability for asbestos-related mesothelioma) attributable to exposure spanning multiple policy periods, it is an implied term that it must present its claims to reinsurers pro rata to the period of exposure (time-on-risk) and may not 'spike' the whole claim into a single chosen year.