definiens: means a Target with respect to which [COMPANY] shall have delivered to the Escrow Agent a Target Reservation Request and in response thereto the Escrow Agent shall have delivered to [COMPANY] a Target Response Notice under Section 4.2(c)(i ) for such Target to become a Reserved Target . A Reserved Target that is replaced pursuant to Section 4.2 will no lo nger be deemed a Reserved Target . For avoidance of doubt : ( i ) the term Reserved Target includes all variants of such Target, including the wild types, naturally occurring variants, engineered variants wherein modifications to the native amino acid sequence have been made ( for example, mutated versions, derivatives or fragments ) and species homologs and orthologs thereof, provided however that any such naturally occurring variant, engineered variant or species homolog or ortholog possesses substantially simi lar biological activity to such Target(s ) ( for example antigenicity in case of antigens ) ; and ( ii ) if a given protein, e.g., an antibody comprises separated amino acid chains which might be delivered by separated mRNA Constructs such proteins would be defi ned as one Reserved Target