G 1/25: Oral proceedings before the Enlarged Board of Appeal on description adaptation

The oral proceedings in G 1/25 (“Hydroponics”) took place today before the Enlarged Board of Appeal (EBA) at the European Patent Office (EPO). As we reported previously, the referral arises from T 697/22 and concerns whether, and on what basis, the description of a European patent must be adapted to amended claims in order to comply with the European Patent Convention (EPC).

This an area where the EPO has historically taken a substantially stricter approach than other patent offices worldwide. In other jurisdictions it is relatively uncommon for the description of a patent to be updated to reflect any claim amendments.

The final decision on this case will have a significant impact on EPO opposition procedure moving forward, and influence whether EPO practice moves closer to, or diverges from, the procedure applied in other countries. 

The case also marks an unusual situation where both the proprietor Knauf Insulation and their opponent ROCKWOOL A/S found themselves on the same side of an issue, arguing against representatives for the EPO itself.

Referred questions

The questions referred to the EBA ask:

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?

Verbal submissions at oral proceedings

During the hearing both the EBA and the EPO acknowledged the significance of this matter to the patent community. This was reflected in the substantial number of amicus curiae briefs filed on the case.

A recurring theme touched on by all parties was the impact of the recent decision in G 1/24 on claim interpretation, which continues to have a ripple effect across the European patent landscape.

There was also considerable discussion of procedural issues. One was – if it is mandatory under the EPC to amend the description to remove inconsistencies, when should such amendments be filed? For example, should amendments accompany the filing of each auxiliary request so that the description can be consulted in line with G 1/24, or may description amendments be deferred until the end of proceedings for efficiency? The EPO’s representatives did not wish to constrain the discretion of their opposition divisions to handle proceedings as they saw fit.

In brief, the three parties’ positions were as follows:

The patentee (Knauf Insulation) argued that the requirement to amend the description finds no proper basis in the EPC. They maintained that Article 84 EPC requires the claims to be supported by the description, but does not require identity of scope between the two. In their opinion any apparent inconsistency between the description and claims can be resolved straightforwardly through claim interpretation.

The opponent (ROCKWOOL A/S) agreed that the EPC does not support a requirement for mandatory amendment of the description. However, as a precaution, they invited the EBA to provide concrete guidance distinguishing between inconsistencies that do contravene the EPC and require amendment to the description and those that do not, and proposed a test for doing so. ROCKWOOL A/S also emphasised that the EPO’s current approach is one of the strictest in the world.

The EPO’s representatives argued that adaptation of the description to match amended claims is necessary to avoid doubt as to the scope of protection of a patent. This helps all users of the patent system, including the public. Consistency also promotes harmonisation and legal certainty across the EPC contracting states, since confusion or doubt as to the scope of a European patent can lead to different decisions in different countries. They pointed to the large number of national jurisdictions, as well as the Unified Patent Court (UPC), in which a European patent can take effect as a key reason why the EPO should adopt a stricter approach than other patent offices, including the USPTO.

It was further argued by the EPO that, while a patent is assessed through the legal fiction of the skilled person, members of the public also read patent documents directly and may be left in doubt as to scope and the EPO has a duty to protect them. This prompted a notable question from Lord Justice Arnold, sitting on the EBA, as to whether patent documents are always to be interpreted through the eyes of the skilled person.

ROCKWOOL further offered what was described as a “non-legal” industry perspective. This emphasised the risks faced by industry when amending the description, in particular the increased risk of introducing added matter. This was noted alongside a lack of awareness of any cases where national courts had encountered insurmountable difficulties because of inconsistencies between the claims and the description of a patent. On that basis, it was explained that, in general, industry is not pressing for the EPO’s current strict requirement.

We will be reporting further as the EBA’s decision is awaited. In the meantime, please contact us if you would like to discuss the potential implications of G 1/25 for your business, or email gje@gje.com.