G1/24 Decision: Enlarged Board of Appeal Clarifies Claims Interpretation
In its recent decision G1/24, the Enlarged Board of Appeal (EBoA) of the European Patent Office (EPO) addressed the long-standing debate on whether the description should be consulted during claim interpretation, and if so, under what circumstances. The decision directly affects how patent claims are understood and applied both at the EPO, the Unified Patent Court (UPC) and national courts.
Summary of the Decision: While claims remain the primary basis for assessing patentability, the decision confirms that the description and drawings must always be consulted when interpreting those claims.
Background
The referral originated from T 0439/22, involving the interpretation of the term "gathered sheet." The proprietor argued for an ordinary meaning understood by a skilled person, while the opponent relied on the description to support its interpretation. The EBoA ruled that:
- The claims are the starting point and the basis for assessing the patentability of an invention under Articles 52 to 57 EPC.
- The description and drawings shall always be consulted to interpret the claims when assessing the patentability of an invention under Articles 52 to 57 EPC, and not only if the person skilled in the art finds a claim to be unclear or ambiguous when read in isolation.
The decision emphasised that the description and drawings are essential interpretative aids - even if claim language appears clear, the skilled person must consult the description to fully understand the invention’s technical context.
However, there remains some nuance: the ruling does not require that the description and drawings be used to determine the final scope of the claims but rather they be consulted in the interpretive process. How this nuance will play out in practice remains to be seen.
Conclusion
G 1/24 resolves a long-standing divergence in EPO practice and aligns it more closely with the interpretation standards applied by national courts and the UPC. While the ruling does not mandate that description and drawings must always be used to determine claim scope, it requires that they be consulted in every case.
This ruling reinforces the importance of claim language but confirms the role of the description and drawings in interpretation. Applicants should therefore draft and amend carefully, as definitions in the description may significantly influence how claims are construed during patentability assessments. Conversely, vague or inconsistent definitions could risk undermining validity.
The full impact of G 1/24 will become clearer over time, but its guidance marks a significant step towards greater clarity and consistency in European patent law.
Written by Lauren Mills for ip21
June 2025