definiens: means any Antibodies, Antisense Compounds, Proteins . assays, reagents or other materials that are ( a ) necessary or reasonably useful for Ihe conduct of the Collaboration, ( b ) Controlled by Schering - Plough, ( c ) utilized in the Collaboration ( but only to the extent so utilized ) and ( d ) either in Schering- Plough 's or any of its Affiliates ' possession as of the PredC{;essor Agreement EITective Dale ( in the case of Organon or Intervet ) or as of the Acquisition Effective Date ( in the case of Schering - Plough and ils Affiliates other than Organon or Intervet ) or discovered or acquired by Schering - Plough or any of its Afliliates during the Collaboration Tenn but outside of the conduct of the Collaboration . Schering- Plough Background Materials excludes Program Targets, Program Antibodies, Program Antisense Compounds and Program Proteins