PATENT | The EPC Board of Appeal on sufficiency requirement in interdependent claims

On 26 August 2025, the EPO Board of Appeal (the BoA) issued its judgment in case no. T 0878/23 (Société des Produits Nestlé S.A. v. Morinaga Milk Industry Co., Ltd.), concerning opposition against a European patent relating to a composition protecting microorganisms within probiotic products. The opposition proceedings focused on whether the patent’s claims met the sufficiency of disclosure requirement set forth in Article 83 of the European Patent Convention (the EPC). Specifically, the patent featured – among others – two interdependent claims apparently inconsistent with each other: (a) claim 1, regarding a composition with a minimum amino acid concentration of 10 wt% or 16 wt% depending on the components used; (b) claim 4, regarding a composition with a minimum amino acid concentration ranging from 3.5 wt% to 36.5 wt%. The BoA held that the concentration ranges defined in the claims are incompatible and therefore, the skilled person cannot prepare a composition as defined in claim 4, which is therefore insufficiently disclosed. Therefore, it revoked the patent.

Newsletter n. 113 – December 2025