definiens: means, with respect to an Ophthalmic Product, the aggregate gross invoice prices of all units of such Ophthalmic Product sold by MERCK or its Related Parties or 10 by ALNYLAM or its Related Parties to Third Parties ( other than a Sublicensee of a Party ) after deducting, if not previously deducted, from the amount invoiced or received : ( a ) trade and quantity discounts actually given other than early pay cash discounts ; ( b ) returns, rebates, chargebacks and other allowances actually given ; ( c ) retroactive price reductions that are actually granted ; and ( d ) a fixed amount equal to three and one - halfoercent ( 3 112 % ) of the amount invoiced to cover bad debt, sales or excise taxes, early payment cash discounts, transportation and insurance, custom duties, and other governmental charges