25.102026

G 1/25 decision EPO – Adapting the Description is no longer an Automatic Requirement

On 3 September 2026, the Enlarged Board of Appeal (EBA) of the European Patent Office (EPO) issued its decision in G 1/25 (“Hydroponics”). The Enlarged Board is the highest judicial authority within the EPO’s independent judiciary and is tasked with ensuring the uniform application of the European Patent Convention (EPC).

Decision G 1/25 answers a question that has divided practitioners for years: when claims are amended, must the description be adapted to match them? The answer is no, not automatically. Adaptation is required only where an inconsistency between the amended claims and the description causes non-compliance with a specific requirement of the EPC.

The test according to G 1/25

According to G 1/25, adaptation of the description is required where all three of the following conditions are met:

  • the claims are amended, during examination or opposition, or in appeal proceedings;
  • the amendment introduces an inconsistency between the amended claims and the description, including any drawings; and
  • because of that inconsistency, one of the EPC requirements in Articles 52 to 57 (patentability), 83 (sufficiency of disclosure), 84 (clarity), 76(1) and 123(2) (added matter), and 123(3) (extension of protection) is not complied with (legal effect).

Points from the decision reasons

  • Inconsistency is narrowly defined. A passage in the description is inconsistent only if it suggests an understanding of an amended claim which is incompatible with the claim’s apparent meaning, and that incompatibility cannot be resolved by reading the application as a whole in line with the G 1/24 decision on claim interpretation (reason 18). The test is whether a skilled person is left in “real doubt” about the claim’s meaning (reason 19).
  • Unclaimed subject-matter is not enough. Embodiments or teachings in the description that fall outside of the amended claims do not, as such, create an inconsistency (reason 20). The EPC does not require purely “formal concordance” between amended claims and description (reasons 22 and 34).
  • Article 84 (clarity). However, an amended claim is not supported if the description leaves it genuinely unclear whether particular embodiments fall within that claim (reason 35).
  • Article 56 (inventive step). Further, if a claim is limited to establish inventive step, and a description passage still expresses the broader technical teaching and conflicts with the inventive-step argument, the resulting inconsistency must be removed (reason 38).

What this means in practice

Less mechanical work. Unclaimed embodiments in the description no longer have to be deleted, or marked as “not part of the invention”, by default. If the amended claims are clear and there is no real doubt whether or not these embodiments are covered by these claims, the description may keep them.

Substance over form. A description review should focus on: passages that leave real doubt about the meaning of the amended claims, statements of technical effect that conflict with inventive-step arguments, and whether the amended claims remain supported by the description.

Examiners must justify their requests. Where an examiner still asks for adaptation of the description, the examiner should indicate the following: the specific passage in the description, the claim reading that passage suggests, why that reading cannot be resolved under G 1/24 by reading the application as a whole, and the EPC requirement said to be breached.

Implementation is still developing. While the G 1/25 decision was still pending, the EPO stated that examining and opposition divisions would continue to apply their Guidelines. The EPO has, however, committed to promptly implementing the EBA’s conclusions in examination and opposition. Early Board of Appeal decisions, such as T 657/24 issued on 15 September 2026, already suggest a more relaxed approach referring to G 1/25, but practice is still settling.

Why G 1/25 matters for patent applicants and patentees

Fewer rounds of description amendment should mean less attorney time and lower prosecution costs, which may make obtaining a granted patent less expensive. This benefit is potential rather than guaranteed. It depends on how examining divisions will apply the G 1/25 test in practice.

We welcome G 1/25 as a shift from formal concordance towards substantive review. It removes an obligation that often produced work without real benefit for the applicant or patentee. However, it does not remove the need for care. The description remains central when claims are interpreted in enforcement, and a description amendment, or the absence of one, may impact a claim’s interpretation. Deleting subject-matter from the description during examination may later be argued as a voluntary waiver, so deletions should always be deliberate.

We recommend the following:

  • avoid adaptation of the description that the G 1/25 test does not require, do not delete embodiments by reflex;
  • carry out a focused review of the description at each significant claim amendment, paying particular attention to statements on technical effects and advantages;
  • ask the examiner to justify any adaptation request by reference to a specific passage in the description, the claim reading it suggests and the EPC article said not to be complied with; and
  • check that any description amendment does not add subject-matter beyond the application as filed.

We will follow how examination practice will develop with respect to adaptation of the description. Our patent team is available to review any inconsistencies between the description and amended claims in your patent applications, in light of the G 1/25 decision.

Etienne Nederlof – European patent attorney

(Read the full decision: https://www.epo.org/en/boards-of-appeal/decisions/g250001eu1)