definiens: shall mean the gross invoiced amount charged by 1ST A or 1ST A Marketing Agent to sell the Product to Third Parties ( other than 1ST A Marketing Agent ) in the Territory, less ( a ) all normal and customary deductions of any type or nature ( such as, e.g., returns, credits, refunds, discounts, allowances, rebates, chargebacks and adjustments ) ; and ( b ) freight, shipping, insurance costs, customs, duties, taxes and other governmental charges and surcharges imposed upon the sale or distribution of the Product . Net Sales shall be determined in accordance with U.S. generally accepted accounting principles, applied on a basis consistent with ISTA 's annual audited financial statements, with interim Net Sales calculations in any year subject to adjustment pending completion ofISTA 's annual audit for that year . For the first and second Financial Years after the Financial Year in which the U.S. First Commercialization occurs, there shall be no limit on the amount of the reductions from gross invoiced amount under this definition . However, for every Financial Year thereafter, the deducted amount may be no more than ! thirty percent ( 30 % ) of the gross invoiced amount ; provided that, in any Financial Year during which a Generic Product is offered for sale in the Territory there shall be no limit on the amount of the reductions from gross invoiced amount under this definition