In G 1/25 of 3 September 2026, the Enlarged Board of Appeal clarifies the previously inconsistent case law on the question of whether the description must also be amended following an amendment to the patent claims. The decision adopts a substantive rather than a formal approach: an amendment is not required merely because the claims and the description do not fully correspond. An amendment to the description is only required if the inconsistency results in a breach of a specific provision of the EPC.
G 1/25 rejects a general obligation to bring the description into full alignment with the amended version of the claims following every claim limitation. In particular, the EPC does not require mere ‘formal concordance’. Technical teachings, examples or embodiments may therefore, in principle, remain in the description even if they are no longer covered by the claims.
A relevant inconsistency only exists if statements in the description or in the drawings suggest an interpretation of the claim that is incompatible with its meaning, and this contradiction cannot be resolved by the principles of interpretation set out in G 1/24. The decisive factor is whether genuine doubts remain in the mind of a person skilled in the art as to the meaning of the claim.
The doctrinal basis of the decision is G 1/24. According to this, the description and drawings must always be taken into account when interpreting the patent claims. The interpretation of claims is a unified, ‘holistic’ process; there is no preliminary step in which the claim is first interpreted in isolation.
At the same time, G 1/25 limits the significance of the description: it may influence the meaning of a claim feature, but must not read into the claim any limitation or extension for which the wording of the claim provides no basis.
In this respect, G 1/25 rejects the case law, in particular that set out in T 1989/18, T 1444/20, T 2194/19 and T 56/21, according to which Article 84 EPC is essentially a ‘one-way street’ and imposes requirements solely on the claims.
According to G 1/25, this view is no longer tenable in the light of G 1/24. If the description is always relevant to the interpretation of the claims, a contradiction between the description and a claim may also impair the clarity or support of the claim.
Nevertheless, Article 84 EPC does not establish a general obligation to make adjustments. Article 84 only becomes relevant if, for example, the inconsistency leaves it unclear whether an example or a embodiment is covered by the claim.
It is worth noting that G 1/25 does not limit the obligation to align the description to Article 84 EPC. Since the description forms part of the interpretation of the claims, an inconsistency may also influence the assessment of novelty, inventive step or other patentability requirements under Articles 52–57 EPC.
Furthermore, the Enlarged Board of Appeal considers that effects on Articles 83, 76(1), 123(2) or 123(3) EPC are, in principle, conceivable, but expects such cases to arise only in exceptional circumstances.
The decision thus establishes the following test:
If an amendment to a claim leads to an inconsistency with the description or drawings, it must be examined whether the inconsistency results in a breach of a specific EPC provision. If this is the case, the description must be amended.
The legal basis is not an abstract obligation to amend the description, but rather the specific EPC provision whose compliance is compromised by the inconsistency.
The practical consequence is a significant restriction on purely formal corrections to the description. Following a limitation of the claims, it is not automatically necessary to delete every embodiment that is no longer claimed or to mark it as ‘not within the scope of the invention’. Rather, the decisive factor is whether it actually influences the interpretation of the claim or gives rise to doubts as to its scope.
At the same time, G 1/25 considerably strengthens the substantive significance of the description: since, according to G 1/24, it is always part of the interpretation of the claim, contradictory passages in the description can no longer be ignored on the grounds that the claim is clear ‘on its own’.
G 1/25 replaces the formal obligation to amend, which had previously been applied in some cases, with a function-based assessment: the description need only be amended to the extent that a specific inconsistency impairs compliance with the EPC. The decision expressly cites Articles 52–57, 76(1), 83, 84, 123(2) and 123(3) of the EPC in this regard.
