definiens: means the gross amount billed or invoiced by Ophthotech or any of its Affiliates or Sublicensees to Third Parties throughout the Territory for sales or othe r dispositions or transfers for value of Licensed Products in the Ophthalmic Field less ( i ) allowances for normal and customary trade, quantity and cash discounts actually allowed and taken, and inventory management fees paid to wholesalers and distributor s, ( ii ) transportation, insurance and postage charges, if paid by Ophthotech or any Affiliate or Sublicensee and included on any such Third Party ’s bill or invoice as a separate item, ( iii ) credits, chargebacks, retroactive price reductions, rebates and re turns, to the extent actually allowed, ( iv ) negotiated payments made to private sector and government Third Party payors ( e.g., PBMs, HMOs and PPOs ) and purchasers / providers ( e.g., staff model HMOs, hospitals and clinics ), regardless of the payment mechani sm, including without limitation off -invoice, rebate, chargeback and credit mechanisms, ( v ) discounts paid under discount prescription drug programs and reductions for coupon and voucher programs ; ( vi ) any tax, tariff, customs duty, excise or other duty or other governmental charge ( other than a tax on income ) levied on the sale, transportation or delivery of Licensed Product and actually paid by Ophthotech or any of its Affiliates or Sublicensees ; and ( vii ) portions of gross amounts billed or invoiced that are written off as uncollectible, not to exceed [ * * ] percent ( [ * * ] % ) of Annual Net Sales in any Calendar Year . In addition, Net Sales are subject to the following : ( a ) If Ophthotech or any of its Affiliates or Sublicensees effects a sale, disposition or transfer of a Licensed Product in the Ophthalmic Field to a customer in a particular country as part of a package of Licensed Products and services ( but not in a Combination Product ), the Net Sales of such Licensed Product to such customer shall be deemed to be of such Licensed Product less applicable discounts pursuant to this definition of Net Sales . For purposes of this subsection ( a ), shall mean the fraction ( A / A+B ), where A equals the value that would have be en derived had such Licensed Product been sold as a separate Licensed Product to another customer in the country concerned on customary commercial terms and B equals the aggregate value that would have been derived had the other components of such package been sold as separate products to another customer in the country concerned on customary commercial terms