Claim amendments and preclusion of pleadings brought in terms of the Counterclaim for revocation

With its decision UPC_CFI_11/2024 of May 8, 2025, the Local Division Düsseldorf clarifies the possibility and the requirements to attack the validity of the patent by introducing new prior art only with the defendant’s Reply to the Defence to the Counterclaim for revocation. Thus, the court has illustrated the possibility of a leave to change the claim or amend the case pursuant to Rule 263 UPC RoP.

Rule 263. 1 UPC RoP states that a party may at any stage of the proceedings apply to the Court for leave to change its claim or to amend its case, including adding a counterclaim. Any such application shall explain why such change or amendment was not included in the original pleading. The leave shall not be granted, if the party applying for the amendment cannot convince the court that:

(a) the amendment in question could not have been made with reasonable diligence at an earlier stage; and

(b) the amendment will not unreasonably hinder the other party in the conduct of its action (Rule 263. 2 (a), (b) RoP).

These two conditions must be fulfilled independently of each other. The burden of proof lies with the applicant.

In the present case, the Local Division Düsseldorf argued that, if the defendant introduces new prior art into the proceedings with his Reply to the Defence to the Counterclaim for revocation (Rule 29 (d) UPC RoP), with which he justifies the lack of novelty and / or inventive step, this is an amendment of the Counterclaim for revocation within the meaning of Rule 263 UPC RoP. The admission of this further prior art can therefore only be considered, if the defendant can convince the court, that the documents in question could not already be submitted with the Counterclaim for revocation and if the admission of further documents does not unreasonably hinder the claimant in the conduct of his action.

According to the court, the same applies, if prior art already submitted with the Counterclaim for revocation, is used for the first time in the Reply to the Defence to the Counterclaim revocation for a new attack on novelty and / or inventive step. Even then, the defendant must convince the court, that it would not have been possible, with due care, to include the (further) attack on novelty and / or inventive step contained for the first time in the Reply to the Defence to the Counterclaim for revocation in the Counterclaim for revocation and that the admission of this further attack on novelty and / or inventive step does not lead to an unreasonable disadvantage to the claimant in the exercise of his rights.

In this context, the court emphasises that the proceedings before the UPC are “front-loaded”. Therefore, the grounds for invalidity must already be asserted in the Counterclaim for revocation. The documents on which the defendant relies to substantiate the Counterclaim for revocation must also be submitted with the Counterclaim for revocation (pursuant to Rule 25. 1 (b), ( c ) and (d) UPC RoP). Taking into account the sequence of pleadings provided in the Rules of Procedure for the standard case and the associated strict time limits, this is the only way to ensure that the claimant is not unreasonably disadvantaged in the conduct of the proceedings.

With this decision, the court clarifies the reasons for the preclusion of a new attack on the validity of the patent if this is only raised with the Reply to the Defence to the Counterclaim for revocation. The same can be expected for the means of defense.

This is of great importance both for the development of an effective defense strategy on the part of the defendant as for ensuring the rights of the claimant.

Author: Dr. Olga Michala

E-mail: michala@paustian.de