definiens: shall mean : ( a ) any corporation or business entity of which fifty percent ( 50 % ) or more of the securities orother ownership interests representing the equity, the voting stock or general partnership interest are owned, controlledor held, directly or indirectly, by MERCK or EXELIXIS ; or ( b ) any corporation or business entity which, directly orindirectly, owns, controls or holds fifty percent ( 50 % ) ( or the maximum ownership interest permitted by law ) or more ofthe securities or other ownership interests representing the equity, the voting stock or, if applicable, the generalpartnership interest, of MERCK or EXELIXIS ; provided that of EXELIXIS shall not include the Change ofControl Group upon completion of a Change of Control of EXELIXIS, so long as such Change of Control Group hasagreed to the restrictions specified in Section 2.1(c )