definiens: means the gross invoiced amount of Product(s ) sold by MERCK, its Affiliates or sublicensees ( which term does not include distributors ) to the first independent third party after deducting, if not previously deducted, from the amount invoiced or received ( it being understood and agreed that MERCK, its Affiliates and sublicensees will not receive any amounts for sales of Product unless such amounts have been invoiced by MERCK, its Affiliates or sublicensees ): ( a ) trade and quantity discounts ; ( b ) returns, rebates and allowances ; ( c ) chargebacks and other amounts paid on sale or dispensing of Product ; ( d ) retroactive price reduction s that are actually allowed or granted ; ( e ) sales commission paid to distributors and/or selling agents ; ( f ) a fixed amount equal to four percent ( 4 % ) of the amount invoiced to cover bad debt, sales or excise taxes, early payment cash discounts, transportation and insurance charges and additional special transportation, custom duties, and other governmental charges ; and ( g ) the standard inventory cost of devices or delivery systems used for dispensing or administering Product which accompany Product as it is sold