EPO President comments on referral G 1/25 concerning adaptation of description

Referral G 1/25 (“Hydroponics”) concerns whether applicants and patent proprietors are obliged to adapt the description to align with amended claims in case of inconsistencies. In his written observations submitted to the Enlarged Board of Appeal on 29 January 2026, the President of the EPO argues that said obligation is important for legal certainty and the quality of European patents.

During the patent grant procedure claims are often amended to meet the patentability requirements of the European Patent Convention (EPC). To avoid inconsistencies with the description, this too should be adapted to align with the amended claims. Case law from the Boards of Appeal for over 40 years has confirmed this requirement to adapt the description when necessary. The EPO follows this case law in its examination and opposition practice.

The clarification of this practice in the 2021 Guidelines for Examination, together with few recent boards of appeal decisions, has prompted questions regarding the legal basis and purpose of this requirement. Users have been involved in the discussions through, amongst others, SACEPO meetings, workshops and at the annual meeting of the US Bar-EPO Liaison Council in December 2025. The matter is now before the Enlarged Board of Appeal for consideration.

The President’s comments to the Enlarged Board of Appeal conclude that Article 84 EPC requires an adaptation of the description in case of inconsistencies between the claims and the description. In examination, this requirement must be complied with before a patent can be granted. In opposition proceedings, the description must be adapted if an amendment introduces an inconsistency, in line with the principles established in G 3/14.

The adaptation of the description ensures that claims and description form one unitary legal title. It fosters harmonised conclusions in post-grant proceedings in all jurisdictions in which European patents may take effect, thus ensuring legal certainty in the European patent system.

The written comments are publicly available via the European Patent Register.