definiens: shall mean either ( a ) a clai m of an issued and unexpired patent included within the VICAL PATENTS, which has not been held unenforceable, unpatentable or invalid by a court or other governmental agency of competent jurisdiction, and whic h has not been admitted to be invalid or unenforceable through reissue, disclaimer or otherwise, or ( b ) a claim in a hypothetical issued paten t corresponding to a pending claim in a patent application within the V ICAL PATENTS, provided that if such pending claim has not issued as a claim of an issued patent within the VICAL PATENTS, within six ( 6 ) y ears after the filing date from which such patent application takes p riority, such pending claim shall not be a VALID CLAIM for purposes of this Agreement . In the event that a claim of an issued patent within th e VICAL PATENTS is held by a court or other governmental agency of comp etent jurisdiction to be unenforceable, unpatentable or invalid, an d such holding is reversed on appeal by a higher court or agency of comp etition jurisdiction, such claim shall be reinstated as a VALID CLAIM hereunder