PATENT | UPC confirms that EPO patent limitations may take effect during pending UPC revocation proceedings

On 25 June 2026, the Paris Central Division of the Unified Patent Court (the UPC) issued its decision in Case UPC_CFI_425/2025, clarifying the effect of a European Patent Office (the EPO) limitation decision adopted while a revocation action is pending before the UPC.

During the revocation proceedings, the patent proprietor requested a limitation of the patent before the EPO pursuant to Article 105a EPC. After the EPO allowed the request, the claimant argued that the limitation should be disregarded, by analogy with Article 105a(2) EPC, which precludes limitation proceedings while an opposition is pending before the EPO.

The Paris CD rejected that argument. It held that Article 105a(2) EPC applies exclusively to opposition proceedings and cannot be extended to revocation actions before the UPC. Once the EPO’s limitation decision is published, the limited patent becomes the only legally effective version of the patent, with retroactive effect under Articles 105b(3) and 68 EPC. Accordingly, the UPC must assess the patent’s validity on the basis of the limited claims, even if the limitation was obtained after the revocation action had commenced.

The Court further observed that Article 33(10) UPCA expressly contemplates parallel EPO limitation proceedings and UPC litigation, confirming that the availability of a stay would otherwise serve no purpose.

The decision confirms that the pendency of a UPC revocation action does not, as such, prevent a patent proprietor from seeking limitation of the patent before the EPO. Once the EPO limitation decision has been published, the limited version becomes the only legally effective version of the patent, with retroactive effect, and the UPC must assess validity on that basis. The UPC does not, however, have jurisdiction indirectly to review the admissibility of the limitation request before the EPO.

Newsletter n. 120 – July 2026