definiens: means, with respect to each Royalty Product and country, the period commencing on the date of the First Commercial Sale of such Royalty Product in such country and ending on the latest to occur of : ( a ) the expiration of the last- to - expire Program Patent or Syros Existing Backgrou nd Target Patent in such country that contains a Valid Claim that claims ( i ) ( A ) the applicable Validated Target or ( B ) any nucleic acid sequence encoding such Validated Targe t, in each case ( ( A ) or ( B ) ), as a composition of m atter ; ( ii ) the Exploitation of such Validated Target with resp ect to any compound or product, including any metho d of treatment related to the Modulation of such Validat ed Target ; or ( iii ) any compound whose primary acti vity is Modulation of such Validated Target, as a compositi on of matter ; provided that, in each case ( ( i)-(iii ) ), the Exploitation of such Royalty Product would infringe such Valid Claim ( or, in the case of a pending Val i d Claim, would infringe such pending Valid Claim if it issue d ) but for ownership of the Patent in which such Va lid Claim is listed or but for the licenses granted to [COMPANY] under Section 3.3.1(b ) ; ( b ) the expiration of Regu latory Exclusivity Period in such country for such Royalty Product ; and ( c ) the tenth ( 10th ) anniversary of s uch First Commercial Sale