On 3 September 2026, the Enlarged Board of Appeal issued its long-awaited decision in G 1/25, providing authoritative guidance on when a patent description must be adapted following amendment of the claims.
According to the order, adaptation is required only where an inconsistency introduced by a claim amendment results in non-compliance with specific provisions of the EPC, including Articles 52-57, 76(1), 83, 84, 123(2), or 123(3) EPC. The decision G 1/25 holds that the EPC does not impose a general requirement of purely formal concordance between claims and description. An inconsistency is not problematic merely because it exists. Rather, the inconsistency must have a legal consequence under the EPC before adaptation becomes necessary.
The decision also builds upon the Enlarged Board’s earlier claim interpretation ruling in G 1/24. The Board confirms that the description and drawings must always be consulted when interpreting claims. At the same time, this does not mean that every embodiment falling outside the amended claims must automatically be deleted or relabeled. The relevant question is whether the remaining disclosure creates a legal deficiency under the EPC.
From a practical perspective, G 1/25 is likely to reduce disputes over extensive “description clean-up” exercises during prosecution and opposition. The focus of a discussion on description adaptation should be on the actual legal effect of an inconsistency rather than on achieving textual perfection throughout the specification.
A takeaway for patent practitioners is: following a claim amendment, the description should be reviewed with a view to substantive EPC compliance rather than formal consistency. G 1/25 introduces a more nuanced framework for description adaptation while reaffirming the continuing importance of the description for claim interpretation.
