definiens: means, in any case where a Product is sold or commercially disposed of for value by Buyer or any Sublicensee in an arm 's length transaction with a third party ( other than an Affiliate of Buyer, it being intended that royalties accrue only once on the same unit of Product }, the gross invoice price for such Product, less the following : -5 R727SI8.9 MPI:939820.2 ( a ) discounts, char_pe- backs, Medicare or other government rebates, and rebates to purchasers actually taken or allowed ; ( b ) credits or allowances given or made for rejections or return of any previously sold Products actually taken or allowed ; and ( c ) to the extent included in such gross invoice price, any tax or government charge imposed on the production, import, export, sale, delivery or use of such Products, including, without limitation, any value added or similar tax or government charge, but not including any tax levied with respect to income