The upper jaw
Term used to describe one of the ways the secondary carrier may calculate its portion of the payment if a patient is covered by two benefit plans. The secondary carrier calculates what it would have paid if it were the primary plan and subtracts what the other plan paid. For example, if the primary carrier paid 80 percent, and the secondary carrier normally covers 80 percent as well, the secondary carrier would not make any additional payment. If the primary carrier paid 50 percent, however, the secondary carrier would pay up to 30 percent.