definiens: means, with respect to any Patent Right, to contest the validity orenforceability of any such Patent Rights, in whole or in part, in any court, arbitration proceeding or other tribunal, including the United StatesPatent and Trademark Office and the United States International Trade Commission, and ( ii ) the term includes ( A ) filing an actionunder 28 U.S.C. § § 2201 - 2202 seeking a declaration of invalidity or unenforceability of any such Patent Rights ; ( B ) citation to the UnitedStates Patent and Trademark Office pursuant to 35 U.S.C. § 301 of prior art patents or printed publications or written statements of the patentowner concerning the scope of any such Patent Rights ; ( C ) filing a request under 35 U.S.C. § 302 for re - examination of any claim of any suchPatent Rights on the basis of any prior art patents or publications ; ( D ) filing, or joining in, a petition under 35 U.S.C. § 311 to institute interpartes review of any such Patent Rights or any portion thereof ; ( E ) filing, or joining in, a petition under 35 U.S.C. § 321 to institute post - grantreview of any such Patent Rights or any portion thereof ; ( F ) becoming a party to an interference with an application for any such Patent Rightspursuant to 35 U.S.C. § 135 ; ( G ) any foreign equivalent of clauses ( A ), ( B ), ( C ), ( D ), ( E ) or ( F ) in any country outside the United States ; or(H ) filing or commencing any opposition, nullity or similar proceedings challenging the validity of any such Patent Rights in any country ; but excludes ( W ) becoming a party to a Third Party interference for the purpose of defending the validity of any such Patent Rights;(X ) filing a request under 35 U.S.C. § 251 for a reissue of any such Patent Rights, ( Y ) any foreign equivalents of clauses ( W ) or ( X ) applicablein any country outside the of United States, or ( Z ) any claim as a defense in any lawsuit or administrative proceeding