A method of determining the amount payable by each plan when a claimant is covered under two or more group plans. The employee’s plan is the primary payer for claims incurred by them and the spouse’s plan is the secondary payer for any balance remaining. The objective is to combine payments so the claimant does not incur any out – of – pocket costs for allowable medical expenses, yet does not receive total payments that exceed 100% of the expense cost.