11.3.3 Relationship between invalidity and infringement proceedings
The EPC created a patent litigation system in which an international court (i.e., the Boards of Appeal of the EPO), the national courts of the Contracting States to the EPC and the Unified Patent Court have concurrent jurisdiction on the validity of a European patent. The European patent as a whole – that is, the entire bundle of patents having equivalent effect to national patents – is subject to the centralized procedure before the EPO and its Boards of Appeal. At the same time, the individual national parts of a European patent are subject to national revocation proceedings (e.g., a German court may revoke the German part of a European patent; and a French court, the French part) and to revocation proceedings before the Unified Patent Court.37
Appeal proceedings before the Boards of Appeal of the EPO and proceedings before national courts or the Unified Patent Court are formally independent of each other. However, a European patent revoked by the Boards of Appeal may not be reinstated by national courts or the Unified Patent Court, and a national part of a European patent revoked by a national court or the Unified Patent Court may not be reinstated by the Boards of Appeal.