definiens: shall mean all United States and foreign patents and patent applications and any divisions, continuations, continuations in part, reissues, reexaminations, renewals and extensions thereof, and all pending applications therefor : ( a ) which are set forth on Appendix A, or ( b ) which claim inventions that are related to IL -1b or derivatives, mutants, variants, fragments or chemical analogues thereof, and which are conceived or reduced to practice in whole or in part by ( i ) employees, agents or contractors of CISTRON during the AGREEMENT P ERIOD or ( ii ) which are licensed to CISTRON, or ( c ) which are derived in whole or in part from material, information or data proprietary to CISTRON and provided by CISTRON to R&D and as reduced to writing by either party within thirty ( 30 ) days of tran sfer and the receipt of which is acknowledged in writing by R&D