definiens: means, on a Licensed Program -by - Licensed Program basis, any and all Patent Rights Controlled by an Acquiring Affiliate, which Patent Rights ( a ) were Controlled by such Acquiring Affiliate immediately prior to the effective date of such Change of Control ; or ( b ) first became Controlled by such Acquiring Affiliate on or after the effective date of such Change of Control ( but are not Controlled by Editas or any of its Affi liates ( excluding for purposes of this provision, any Acquiring Affiliate ) ) and solely claim Excluded Know -How ; provided, however, that, in all cases, Excluded Patents shall not include any Patent Rights that ( i ) comprise any substitutions, divisionals, co ntinuations, continuations -in - part, reissues, renewals, registrations, confirmations, re -examinations, extensions, supplementary protection certificates and the like of any Editas Licensed Background Patents, Editas Licensed Collaboration Patents, Joint Co llaboration Patents or Joint Patents that were Controlled by Editas ( or any of its Affiliates ) prior to such Change of Control, as well as any other Patent Rights that claim priority to any of any such Editas Licensed Background Patents, Editas Licensed C ollaboration Patents, Joint Collaboration Patents or Joint Patents, or ( ii ) are practiced by or on behalf of Editas or any of its Affiliates ( including any Acquiring Affiliate ) in the performance of the applicable Licensed Program or any other obligations under this Agreement or the Master Collaboration Agreement