definiens: shall mean a polypeptide chain ( ) \whose I L Carboxy - tenninal7 - cysteine domain sequence~ set forth on Appendix B to this Agreement and shall include : ( a ) i species)variant forms thereof ; ( b ) amino acid variant forms of the Protein sharing at least ~ aminO acid sequence identity with thelCarboxy - terminal 7 -cysteine domain sequencejof the Protein ( ' ~5%IHomologs " ) ; - 8 -(c ) l : runcated fariant fonns of the Protein or suc~ specieslvariant fonns or the ( 85 % iHomologs, including, without limitation, polypeptides comprising only th9"I - cysteine domain or fragments)tbereof ; ( d ) hoIOOdimeric, heterodimeric and chimeric fonns of the Protein and of any of the variant fonns thereof identified in the preceding Subsections ( a ), ( b ) and ( c ), to the extent they also consist of : ( i ) the Protein or variant fonns thereof identified in the preceding Subsections ( a ), ( b ) and ( c ), or ( ii ) other polypeptide chains which are not within the preceding Subsection ( i )