Action to be directed against the patent proprietor
Rule 42 UPCARoP relates to standing to be sued in revocation actions. According to Rule 42, a revocation action must be directed against the patent proprietor. In terms of its meaning, Rule 42 corresponds to Art 47(5) UPCA which stipulates for an action brought by the licensee that the validity of a patent cannot be contested where the patent proprietor does not take part in the proceedings (first clause) and which for the Counterclaim for revocation requires as a mandatory provision the involvement of the patent proprietor. Art 47(6) UPCA merely defines the group of persons entitled to bring an action for an isolated revocation action and makes general reference to the Rules of Procedure without expressly naming the patent proprietor as a necessary defendant.