definiens: means with respect to a LICENSED PRODUCT and/or LIC ENSED SERVICES, the gross amount invoiced by REGENERON or its AFFILIATE S for the sales of LICENSED PRODUCTS and/or the performance of LICENSED SERVICES to a TH IRD PARTY, less : ( a ) trade, quantity and cash discou nts actually allowed ; ( b ) discounts, refunds, rebates, charge backs, retroact i ve price adjustments, and any other allowances actually granted which effectively reduce the net s elling price ; ( c ) product returns and allowances actually granted ; ( d ) any tax, tariff or duty imposed on the production, sale, delivery or use of the product ( excluding federal, state or local taxes based on income ) ; and ( e ) freight, postage, shipping, customs duties, excises and insurance charges actually allowed or paid for delivery of LICENSED PRODUCTS, to the extent billed