Present procedures at the European Patent Office (EPO) require adaptation of the description of a European patent application to avoid inconsistencies with allowed claims. Much controversy has surrounded such description amendments, with the Boards of Appeal (BoA) issuing divergent decisions on whether there is legal basis for such a requirement. This divergence in case law, along with inconsistent application in the practice of aligning the patent description with amended claims, has necessitated this referral to the Enlarged Board of Appeal (EBoA) of the EPO.
Background
Current practice at the EPO requires that the description of a patent application be brought into conformity with the allowable claims.
This practice, while intended to improve clarity and avoid ambiguity about the subject matter for which protection is sought, is not only time-consuming but it may also introduce risks for the applicant. Even minor amendments to the description may substantively affect how the claims are interpreted. In certain circumstances there is an inherent risk of inadvertently adding subject matter.
Many applicants have therefore been reluctant to adapt the description to remove any such inconsistencies.
In T 697/22 (the case underlying this referral), the Board considered whether it was necessary to adapt the description to the amended claims.
The Board examined the relevant case law concerning amendments to the description and found two conflicting approaches:
- a first line of case law where there is a legal basis that requires the description to be consistent with the amended claims (although there was no consensus in these decisions on one precise legal basis); and
- a second line of case law where there is no legal basis, an inconsistency between an amended claim and the description was no impediment to grant a patent.
It was the view of the BoA that this clear divergence in the case law necessitated a referral to the EBoA.
Referral to the EPO Enlarged Board of Appeal
On 29 July 2025, a referral (G 1/25) to the EBoA was made with interlocutory decision T 697/22.
Whilst the case before the referring Board relates to an opposition appeal case, the referring Board noted that the referral affects the practice of all departments of the EPO, from examination through to opposition appeal.
G 1/25 refers the following questions to the EBoA:
- If the claims of a European patent are amended during opposition proceedings or opposition-appeal proceedings, and the amendment introduces an inconsistency between the amended claims and the description of the patent, is it necessary, to comply with the requirements of the EPC, to adapt the description to the amended claims so as to remove the inconsistency?
- If the first question is answered in the affirmative, which requirement(s) of the EPC necessitate(s) such an adaptation?
- Would the answer to questions 1 and 2 be different if the claims of a European patent application are amended during examination proceedings or examination-appeal proceedings, and the amendment introduces an inconsistency between the amended claims and the description of the patent application?
The referring Board highlighted that the fundamental character of these questions is reinforced by the order in G1/24, which states that the description and drawings must always be consulted to interpret the claims.
Final Remarks
The question of whether an application can be granted or a patent upheld if there is an inconsistency between an amended claim and the description has become of even greater significance following G 1/24.
Referral G 1/25 (if deemed admissible) could put an end to the controversy surrounding both pre-grant and post-grant description amendments.
In the meantime, we maintain our advice to carefully consider any amendments to the description, including those proposed by the EPO examiner.
