LD Brussels, August 17, 2026, Order on Admission of Auxiliary Request, UPC_CFI_806/2025, UPC_CFI_185/2026

Granting leave to amend at a late stage would allow the applicant to change its litigation strategy after the fact. A diligent patentee should coordinate its EPO and UPC positions from the beginning, rather than reacting once parallel proceedings develop unfavorably. The Court found that both cumulative conditions of R. 263.2 RoP were unmet, as the amendment could have been foreseen and pursued with reasonable diligence from the outset of the proceedings and admission at this advanced stage would force the defendant to newly assess validity and infringement of previously unasserted claims.

That an applicant may later need to start new UPC proceedings based on auxiliary requests allowed by the EPO but not by the UPC is a risk the applicant itself created and must bear, not a ground for admitting a late amendment.

Since the counterclaim for revocation determines the scope of the revocation proceedings, an auxiliary request directed at claims never challenged in that counterclaim does not qualify as a defence to it and can be refused admission on that basis alone.