Recently, the EPO’s Enlarged Board of Appeal issued its long-awaited decision in G1/25 on the formal requirements for adaptation of description and drawings of patents and patent applications following claim amendments. While many had anticipated the decision to endorse one of the two diverging lines of case law, it has instead taken a nuanced position and possibly relies on future decisions to decide the ultimate influence that it might have on European patent practice.

The EPO has long been the outlier amongst other major patent offices across the world for having formal requirements for description amendments. Article 84 EPC is frequently cited as the most relevant legal basis for this requirement, however, there have been split views on whether or not the article actually really imposes a requirement that the description is supported by the claims, a point extensively discussed in a number of amicus curiae submissions for this decision.

The Enlarged Board’s answers

The Enlarged Board answered the referred questions as follows:

Question 1: 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?

Answer: If the inconsistency is such as to cause a non-compliance with the EPC, Question 1 is to be answered “Yes”.

Question 2: If the first question is answered in the affirmative, which requirement(s) of the EPC necessitate(s) such an adaptation?

Answer: The answer to Question 2 does not lie in a single provision of the EPC which, in all circumstances, mandates an adaptation of the description, including any drawings, whenever the claims are amended. Whether such an adaptation is required depends on whether, in the circumstances of the case, the inconsistency is such as to result in non-compliance with a requirement of the EPC.

Question 2 is therefore to be answered to the effect that the legal basis for any necessary adaptation is the provision of the EPC with which compliance is lacking by reason of the inconsistency in question.

Question 3: 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?

Answer: No.

One of the most significant practical consequences of G1/25 is that amendments can no longer be justified merely because the description is untidy or not perfectly aligned with the claims. The Enlarged Board was clear that adaptation must be linked to a specific EPC requirement. If an amendment to the description is requested, the examining division, opposition division or the opponent must supplement such a request with a reference to the provision of the EPC that is allegedly not complied with as a result of the inconsistency. Hence, the previous notion of a general obligation to tidy up the description following amendment appears difficult to reconcile with the Enlarged Board’s reasoning.

Another highlight of this decision was the use of the terms “inconsistency”, “incompatibility” and “real doubt”. According to the Board an “inconsistency” would exist where statements in the description are “incompatible” with the apparent meaning of the claim, and that its incompatibility cannot readily be resolved through claim interpretation by applying the principles of G1/24. The Board goes on further to say that if the person skilled in the art reading the claim in light of the description and drawings will be left in “real doubt” as to the meaning of the claim, there is an inconsistency. This also includes the instance where it is not clear whether a statement in the description falls within the scope of the claims. We may expect that, in future decisions, arguments advanced by attorneys will focus on what constitutes “real doubt”, a term importantly distinct from the more frequently used EPO term “serious doubt”, which may set a lower bar (or create a fuzzy border region) for what is doubtful.

Perhaps the clearest theme running through G1/25 is the influence of G1/24. G1/25 builds directly on the interpretative framework established by G1/24, meaning that every statement in the description must be read onto the claims. However, in terms of “consulting” the description as directed by G1/24, G1/25 suggests that the skilled person would have a more objective approach when viewing what is relevant for interpreting amended claims.

From a practice point of view, whilst we would expect that fewer description amendments would be required now, parties are likely to spend considerably more time debating whether a particular passage gives rise to “real doubt”. In opposition proceedings, it is likely to become more difficult and time consuming for parties to agree on the form of a description especially where they are now required to put forward arguments based on substantive requirements. The result might be fewer amendments overall, but a more demanding review process and significantly more attorney time devoted to justifying or resisting those amendments.

The implications of G1/25 may also extend beyond EPO proceedings. Arguments advanced during prosecution or opposition to justify deletion of specific passage could later influence claim interpretation in national proceedings. Equally, deletion of embodiments can be viewed by some as an implicit acknowledgement that those embodiments are inconsistent with the claimed invention, potentially influencing subsequent arguments on novelty and inventive step.

Hence, it appears that in formulating the answers to the referred questions, the Enlarged Board has reframed the issue by moving on from the provisions of Article 84 and referencing the EPC more widely – this means that whilst including statements in the description which do not fall within the scope of amended claims is not disallowed, we should remain cautious of such statements violating other provisions of the EPC, particularly Articles 52-57, 76(1), 83, 84, 123(2) and 123(3), as highlighted by the Board.

Overall, the decision represents a notable shift in assessment of the description. Description adaptation is no longer simply a matter of formal conformity. Whether an amendment is required now depends on substantive EPC compliance and the legal consequences of any inconsistency. While we may expect the EPO to demand fewer amendments in future proceedings, it is likely that the complexity, strategic importance, and cost of deciding which passages can be removed and which can safely remain in the description will increase. Whether this ultimately leads to greater certainty or merely to a new generation of disputes over “real doubt” and “inconsistency” will be determined by the first cases that apply G 1/25 in practice.

This article was written by Trainee Patent Attorney, Jasmeet Kaur. If you would like to discuss this topic or something else, please get in touch at jasmeet.kaur@wilsongunn.com or contact one of our attorneys for advice.