UPC Court of Appeal: Procedural Decision: (No) New Grounds for Revocation in Case of Patent Amendments

If an application to amend the patent is filed, the plaintiff must file a reply to the application to amend (R 43.3 RoP). Where appropriate in view of the proposed amendments, the reply may contain alternative arguments on non-infringement (R 32.2 RoP). However, the reply to the application to amend does not give the plaintiff an opportunity to introduce new grounds for revocation against the patent as granted (e.g. new prior art references challenging novelty or inventive step), unless the amendment of the submissions is admitted pursuant to R 263. New arguments may be admitted taking into account specific circumstances of the case. The rules are also to be interpreted in the light of the principle of proportionality. R 44 RoP only requires an "indication" of the relevant facts, which argues against an overly strict application. Furthermore, the principle of fairness in the application of the principle of audiatur et altera pars may require that the plaintiff in a revocation action be allowed to introduce new facts or evidence – for example, to substantiate earlier submissions on common general knowledge or to rebut counter-evidence from the opposing party on this point (UPC 29.12.2025, CoA 71/2025).