Keywords: patents, European Patent Office (EPO), amendment, description, claims, Enlarged Board of Appeal (EBA), G1/25, description amendments
Background
A long-running debate in European patent practice is now under formal review. The question is simple: must the description always be amended to match the claims?
The issue has been referred to the G 1/25 Enlarged Board of Appeal referral. A decision is pending. Its outcome could shape how every European patent application is prosecuted.
For now, applicants and patentees still face the same practical question: should you continue amending the description to align with the claims?
The requirement itself is closely associated with the practice of the European Patent Office. Many other patent offices do not impose the same level of scrutiny.
At the EPO, the practice is set out in the EPO Guidelines for Examination and has been applied since the introduction of the European Patent Convention in 1973.
What remains contested is the legal basis.
Some practitioners point to provisions on clarity and support under Article 84 EPC and the extent of protection under Article 69 EPC. Others argue that the Convention contains no explicit requirement to amend the description in this way.
That divide has now reached the Enlarged Board.
Case Summary
The referral arises from T 697/22, an opposition case involving a hydroponic plant-growing medium owned by Knauf Insulation.
During opposition proceedings, the patentee submitted an auxiliary request together with amendments to the description. The Opposition Division maintained the patent on that basis.
On appeal, the Board refused the description amendments. The opponent then argued that the remaining description was inconsistent with the claims.
This left the patentee in a difficult position. The claims were acceptable, but the description could not be amended as proposed. The result was a procedural stalemate.
To resolve the issue, the Board referred questions to the Enlarged Board under G 1/25 Enlarged Board of Appeal referral.
The Questions Referred
The Enlarged Board has been asked to clarify three key points.
1. If an inconsistency arises between amended claims and the description during opposition or opposition-appeal proceedings, must the description be amended to align with the claims?
2. If alignment is required, what provision of the EPC provides the legal basis?
3. Does the same principle apply during examination and examination-appeal proceedings?
The third question carries the widest impact. If the answer is yes, as many expect, the decision will affect the prosecution strategy for all European patent applications.
Risks Created by Description Amendments
The patentee in the referral argued that mandatory alignment can create new legal risks.
One concern is added matter. If unclaimed subject matter in the description influences how the claims are interpreted, removing that text could change the interpretation. That shift may trigger an objection under Article 123(2) EPC.
Another risk involves enablement. Removing descriptions of unclaimed embodiments may inadvertently delete technical information needed to support the invention.
These concerns have gained further weight following the Enlarged Board’s decision in G 1/24 Enlarged Board of Appeal decision. That ruling confirmed that the description must always be consulted when interpreting the claims.
In practical terms, this increases the importance of the description and raises the stakes when it is amended.
At Wynne-Jones IP, we recognise the force of these arguments. Description amendments can solve one problem while quietly creating another.
What This Means in Practice
The Enlarged Board has not yet delivered its decision in G 1/25 Enlarged Board of Appeal referral. Until then, the European Patent Office is expected to maintain its current practice.
In other words, description alignment remains the working standard.
Applicants should therefore continue to amend the description where required. But those amendments should be made carefully and strategically.
Two practical safeguards help reduce risk:
· Draft clear, self-contained claims. The clearer the claims, the less reliance there is on the description during interpretation.
· Review examiner-proposed description amendments closely. Remove or amend text only where necessary. Avoid deleting technical detail that may later support the invention.
This is not an administrative step. It is a strategic decision point in European prosecution.
Strategic Support
Description amendments can influence claim interpretation, validity, and enforceability. They deserve close attention.
If you would like to discuss the most effective approach to description amendments for your European patent or application, the team at Wynne-Jones IP can help. We work with clients to implement amendments that comply with EPO practice while protecting the commercial strength of their patents.
Ashleigh Kirs European Patent Attorney
Ian Lambert Director, UK Chartered and European Patent Attorney
