The Court shall decide on the validity of a patent on the basis of an action for revocation or a counterclaim for revocation.

The Court may revoke a patent, either entirely or partly, only on the grounds referred to in Articles 138(1) and 139(2) of the EPC.

Without prejudice to Article 138(3) of the EPC, if the grounds for revocation affect the patent only in part, the patent shall be limited by a corresponding amendment of the claims and revoked in part.

To the extent that a patent has been revoked it shall be deemed not to have had, from the outset, the effects specified in Articles 64 and 67 of the EPC.

Where the Court, in a final decision, revokes a patent, either entirely or partly, it shall send a copy of the decision to the European Patent Office and, with respect to a European patent, to the national patent office of any Contracting Member State concerned.