definiens: means, and determined on a Licensed Product - by­Licensed Product and country - by - country basis, the period commencing from the First Commercial Sale of a given Licensed Product in such country and ending on the expiry of the last­to - expire Licensor Patent containing a Valid Claim Covering such Licensed Product in such country For purposes of this Section 10.9(c ), the definition of and Sections 5.4 through 5.9 shall apply mutatis mutandis to the calculation, payment, recording, and auditing of Checkpoint 's obligations to pay Reverse Royalties under this Section 10.9 as they apply to TGTX and, solely for such purpose, each reference in each such Section ( and any related definitions ) to TGTX shall be deemed to be a reference to Checkpoint, and ( y ) a Sublicensee shall be deemed to be a reference to a licensee or sublicensee of Checkpoint or any of its Affiliates ( and expressly excluding Existing Sublicensees ) with respect to the Licensed Product . Notwithstanding the foregoing, no Reverse Royalty shall be due or payable by Checkpoint relating to Net Sales of Sublicensees under any Sublicense in effect at the date of termination of this Agreement ( Sublicensees under such Sublicenses, ) . means sales - based royalties, and minimum sales royalties, each as actually received by Checkpoint or its Affiliate from an Existing Sublicensee as consideration for the grant of rights to Patent Rights