BREAKING NEWS – finally, a referral on description amendments

In G1/25, an EPO Board of Appeal has asked the Enlarged Board of Appeal (EBA) to consider whether it is really necessary for the description of a European patent or application to be amended to remove inconsistencies with allowed or granted claims.
 
It seems unlikely that G1/25 will entirely remove the requirement to amend the description in this way. However, we may see a more moderate approach being adopted, or at least a clearer approach that encourages consistency across EPO Examining and Opposition Divisions.
 
The EBA decision in G1/25 could take many months to arrive. The EBA does not normally convene rapidly, being composed of high-level EPO and external judges. However, we hope that these questions are resolved soon, since there is the possibility of proceedings before the EPO being stayed in situations in which “the outcome of examination or opposition proceedings depends entirely on the answer to the questions referred to the Enlarged Board of Appeal”¹.
 
In the meantime, our advice to proprietors and opponents is as follows.
 

Proprietors

Keep your commercial goals in mind and be careful about amendments that could alter claim interpretation, particularly amendments proposed by EPO Examiners.
 

• Following another recent EBA decision (G1/24), the description should always be consulted when interpreting the claims at the EPO (see our article on G1/24 here). This is also the situation at the UPC². National courts may also look at the description and/or the file wrapper when interpreting the claims, although the approach varies from jurisdiction to jurisdiction. As such, any description amendment that could alter the interpretation of the claims should be made with great care, since it could alter the interpretation (and hence the scope or validity) of the claims. Keep your commercial goals for each case top of mind when amending the description.
   

• There will often be a mismatch between what an applicant would choose to keep when asked to bring the description into conformity with the claims and the amendments an Examiner would make when given the same task. If the Examiner makes amendments to the description the applicant will be left considering whether to argue against those changes. By being proactive in making changes to the description when given the chance in prosecution, the applicant stands a better chance of getting their preferred version of the text.
   

• If you do find yourself faced with amendments proposed by an Examiner, consider whether you should be pushing back, especially if the Examiner is seeking to characterise the ‘invention’ and/or ‘scope of protection’ (‘protection’ being a matter for national courts and the UPC, not the EPO).
   

• If you have a particularly intransigent EPO Examiner who is insisting on certain description amendments to secure allowance, consider if you should put a statement on the record that the applicant does not agree to one or more of the description amendments (e.g. deletion of a reference to “equivalents”) when approving the text for grant.
   

• Consider if it is tactically useful to request a stay of proceedings, pending the outcome of G1/25, if it can be argued that the outcome of examination or opposition proceedings depends entirely on the answer to the questions referred to the EBA.

Opponents

Attacks may be available when there are inconsistencies between the claims and description, and keep in mind the possibility of attacks based on the description being consulted to interpret the claims (as required by G1/24).
 

• Regardless of the outcome of G1/25, opponents should keep in mind that the description will always be consulted at the EPO when interpreting the claims (following G1/24). This can open up attacks on all grounds of opposition, but particularly novelty and inventive step, for example where the description defines a claim term more broadly than is normal in the art.
   

• Consider if statements in the description bring into question the clarity of the claims. Whilst clarity is not a ground of opposition, if a patentee amends a claim by incorporating a feature from the description, clarity does become an available ground. If there are statements in the description that cast doubt on the scope of the new feature, point this out. This might not have otherwise come to light until the description is amended by the proprietor after a claim request has been upheld, by which point it will be too late to raise the objection.
   

• Consider also if amendments to the description during opposition proceedings could lead to a change in scope of the claims. If the scope is potentially expanded (for example, due to the deletion of a potentially limiting definition), an objection under Article 123(3) EPC could potentially be raised that the scope of the claims has been impermissibly extended.
   

• As for proprietors, consider if it is tactically useful to request a stay of proceedings, pending the outcome of G1/25.
   

For more detail on the background and what happens now, please read on.
 

Background to the new referral

At the EPO, decisions of Examining Divisions (before grant) or Opposition Divisions (after grant) can be appealed to a Board of Appeal. Unlike in some national proceedings, no higher appeal is available.
 
However, Boards of Appeal can send specific questions on points of law to the Enlarged Board of Appeal, composed of high-level EPO judges and often national judges. That is what has happened in G1/25. The questions referred to the EBA are:
 

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

For context, the patent in the underlying appeal (T 697/22) claims a hydroponic method of growing a plant. The growing medium contains a specific binder.
 
The key claim is claim 1 of Auxiliary Request 1E, which was filed during oral proceedings in the first instance opposition. It reads:
 
"1. A method of growing a plant, characterised in that the plant is grown in a hydroponics growing medium comprising mineral fibres and an organic binder, wherein the growing medium has a Weathered Interlaminar Strength of at least 4 kilopascals and a phenol content of less than or equal to 0.01 % by weight and in which the organic binder is based on a reducing sugar and comprises at least one Maillard reaction product, and in which the binder is based on reaction products obtained by curing an aqueous solution comprising citric acid, ammonia and dextrose." (Underlining shows the difference compared to method claim 13, when dependent on product claim 1, of the patent as granted.)
 
The Opposition Division decided to maintain the patent based on Auxiliary Request 1E, together with an amended description. Both parties appealed that decision.
 
At appeal, the proprietor kept Auxiliary Request 1E, together with the same amended description, as one of their requests.
 
In written appeal proceedings, the opponent pointed out an inconsistency with that amended description and the specific binder in Auxiliary Request 1E. The amended description included paragraphs [0013] and [0016] which left open the possibility for the binder to be something other than the specific binder claimed. 
 
At oral proceedings in appeal, Auxiliary Request 1E with the description as amended in opposition was found to be allowable in all respects, except for one difficulty: this inconsistency between the claims and description.
 
EPO case law diverges on whether this inconsistency prevents compliance with the EPC.
 

• Most case law requires the description to be consistent with the claims. This means if claim amendments (whether in examination or opposition) introduce an inconsistency with the description, the description must be amended to remove the inconsistency.
   

• However, a number of decisions have bucked this trend, finding there is no legal basis to make an applicant or proprietor adapt the description when an amendment of the claims has caused an inconsistency with the description³.
   

Given the diverging approaches, the Board of Appeal in the present case found that it could not decide on the allowability of Auxiliary Request 1E with the description as amended in opposition until its questions had been settled by the EBA.
 

What now?

EPO Examining Divisions have in recent years (especially since the introduction of the 2021 edition of the EPO Guidelines for Examination) adopted a strict approach to amending the description for conformity with the claims.
 
The official expectation, according to part F-IV,4.3 of the EPO Guidelines, is that applicants will seriously consider deleting embodiments in the description that are no longer covered by amended independent claims. If retained, such embodiments must in principle be individually marked ‘so that it is clear that they do not fall within the subject-matter for which protection is sought’. Officially, an inconsistency between the description and the claims cannot be removed by introducing a generic waiver at the beginning of the description (in practice, some Examiners remain willing to accept this).
 
In G1/25, we might see a softening of what is required of applicants and proprietors when amending the description for conformity with the claims. There is an argument the EPO has stepped outside its jurisdiction in requiring severe description amendments. A softening would be welcome to mitigate problems (e.g., estoppel, interpretation) that amending the description may cause in national court or UPC proceedings. On a less fundamental but still important level, it would be welcome because of the basic cost of a wholesale review of the description, which may be incurred not only in examination proceedings but also in opposition proceedings if the claims are amended after grant.
 
Although not impossible, the practice of requiring description amendments seems unlikely to vanish entirely. This practice is longstanding at the EPO. Most case law supports description amendments. Although not binding, the current EPO President’s view is that Article 84 EPC necessitates descriptions to be amended to conform with amended claims⁴.
 
As noted above, there is also the impact of recent Enlarged Board of Appeal decision G1/24. In this decision, the EBA ruled that the description should always be consulted when interpreting the claims. In G 1/25, the EBA might consider it essential for the description to be aligned with the claims if the description will always be consulted to interpret the claims after grant.
 
It is likely that ahead of any decision by the EBA, amicus curiae briefs will be filed and the President of the EPO will comment with a view (likely to reiterate that expressed in the President’s comments on G1/24, noted above). Watch this space for more information as the case develops.
 
For earlier coverage of the topic of description amendments at the EPO, see our articles here and here. If you have any questions relating to this topic, please get in touch with Anne-Marie Conn, Jess Smart, Tom Leonard or your usual Kilburn & Strode advisor.
 

1. EPO Guidelines at E.VII.3 https://www.epo.org/en/legal/guidelines-epc/2025/e_vii_3.html
2. NanoString v 10x Genomics, UPC Court of Appeal, 26 February 2024 – UPC_CoA_335/2023
3. T697/22 - Interlocutory Decision of 29 July 2025, p.51, pt. 15.1.1
4. Letter of the President of the EPO to the Enlarged Board of Appeal in G1/24, dated 7 November 2024, p.17, pt. 72.