Each Party shall immediately provide the other Party with written notice reasonably detailing any (i) known or alleged infringement of any Agios Patents, Celgene Collaboration Patents or Joint Patents, or known or alleged misappropriation of any Agios Know-How, Celgene Collaboration Know-How or Joint Inventions, by a Third Party, (ii) “patent certification” filed in the United States under 21 U.S.C. §355(b)(2) or 21 U.S.C. §355(j)(2) or similar provisions in other jurisdictions, and (iii) any declaratory judgment, opposition or similar action alleging the invalidity, unenforceability or non-infringement of any such intellectual property rights (collectively “ Third Party Infringement ”).