definiens: means [COMPANY] Collaboration Intellectual Propertyonly to the extent that it is actually used in such Program prior to the applicable reversion set forthin this Section 2.12 ; provided further that the foregoing license under this Section 2.12.2 shall be [ * * ] with respect to the applicable Program to the extent of claims within the Patents included inthe [COMPANY] Collaboration Intellectual Property and Joint Collaboration IP that Cover acomposition of matter of any such Program Compound or Program Product . Agios shall not oweroyalties or milestones with respect to any license in this Section 2.12.2, but Agios shall be solelyresponsible for any payments owed by [COMPANY] to any Third Party licensors of CelgeneCollaboration Intellectual Property or Joint Collaboration IP, and shall be responsible forcomplying with the terms of any license agreements with such third Party licensors, in eithercase, directly related to Agios ’ exercise of such licenses2.12.3 Optioned Programs . For the avoidance of doubt, none of the reversionevents described in this Section 2.12 shall affect [COMPANY] ’s rights with respect to any otherProgram for which [COMPANY] retains Option rights or has delivered an Option Exercise Noticepursuant to Section 3.1.2(a )