G1/25: Enlarged Board of Appeal decides on description amendments to conform to amended claims

The long-running debate over the need to amend the description to conform to amended claims has finally been addressed by the Enlarged Board of Appeal (EBoA) in its decision G1/25. However, it is not yet clear how this will affect European patent practice.

Since 2021, the EPO has increasingly enforced a uniquely strict approach to amendment of the description, requiring it to be amended to conform to the amended claims before grant or maintenance of a patent. As explained in our previous article here, for several years there have been two diverging lines of Board of Appeal case law. One line argued that a description which does not conform to the claims violates some of the requirements of the European Patent Convention (EPC), such as clarity under Article 84 EPC. The other line questioned whether there was any legal basis for requiring such description amendments within the EPC. The referral in G1/25 sought to resolve this divergence.

The EBoA has now issued its decision which provides a compromise between the above two extremes, where description amendments are only required if the inconsistency between the description and claims leads to non-compliance with the EPC. This appears logical on first reading, but raises questions as to what constitutes an inconsistency and how non-compliance will be determined.

The EBoA has specified that an “inconsistency” between the description and the claims only exists where one or more statements in the description, including any drawings, suggest an understanding of a claim that is incompatible with its apparent meaning, and which cannot be readily resolved by established claim interpretation principles following G1/24 (which we discussed in our previous article here).

The decision should remove the requirement to amend the description to strictly conform to the amended claims. However, the decision is likely to be interpreted differently by different examiners with some adopting a stricter view as to when an inconsistency is present and when such an inconsistency leads to non-compliance with the EPC. It is also likely to be interpreted differently by different parties during opposition and appeal proceedings.

Background

The referral arose from interlocutory decision T 0697/22 in opposition appeal proceedings concerning a patent owned by Knauf Insulation, opposed by ROCKWOOL A/S. The referring Board found the amended claims allowable but identified an inconsistency between the amended claim language and certain passages remaining in the description.

The key legal issue was whether that inconsistency itself rendered the patent non-compliant with the EPC and, if so, what legal provision mandated correction.

The Enlarged Board was asked three questions which are summarised below:

1. Is amendment of the description necessary when amended claims create an inconsistency with the description?
2. Which provisions of the EPC provide the legal basis for any such requirement?
3. Would the answers to the above differ if the claims are amended during examination proceedings, or examination-appeal proceedings?

The third question was answered succinctly, “No”.

Impact of G1/24

One of the key aspects of the decision is the reaffirmation of the principles of claim interpretation established following G1/24. In G1/24, the EBoA held that the description and drawings must always be consulted when interpreting a claim and not merely when the claim is unclear.

The EBoA in G1/25 has taken the opportunity to further clarify how G1/24 should be interpreted and applied; it endorses the decision T 439/22 which applied G1/24 and sets out the following principles:

• Claim interpretation is the result of reading the claims, the description and drawings as a unitary process (“holistic approach”) to determine the meaning which the skilled person gives to the claim wording in the context of the application or patent as a whole.
• The description and the drawings may affect the meaning which the skilled person attributes to the claim wording, but they cannot be used to impose on the claim a limitation or expansion for which the claim wording provides no basis.
• The skilled person should read terms in the claim in the sense of a definition found in the description, taking into account both the broadening and limiting aspects as long as the definition is technically reasonable and complies with the overall teaching of the claims, description and drawings.

In G1/25, the EBoA enables the above claim interpretation principles of G1/24 to resolve any apparent inconsistency between the description and claims without requiring amendment. For example, a claim defining that a motor is a brushless motor would therefore seemingly not require the description to be amended to remove any mention of the motor alternatively being a brushed motor.

5 point test

The reasoning of the decision arguably imposes a stringent limitation on the circumstances in which an Examining Division, Opposition Division (OD) or Board of Appeal (BoA) may require an amendment to the description to conform to the claims. In particular, the following conditions need to be met:

1. There is an inconsistency between the amended claims and the description/drawings.
2. The inconsistency suggests an understanding of a claim which is incompatible with the apparent meaning of the claim.
3. That incompatibility cannot be readily resolved by applying the principles of established claim interpretation following G1/24.
4. The skilled person reading the claim in the light of the description and drawings would be left in real doubt as to the meaning of the claim.
5. The inconsistency causes non-compliance with one or more of Articles 52 to 57, 76(1), 83, 84, 123(2) or 123(3) EPC.

Only an affirmative response to all five above conditions results in an amendment being necessary.

Although such a test appears to prohibit a description amendment being required for all but the most egregious inconsistencies between the description and claims, there are multiple terms used to define these conditions that could be differently interpreted. For example, some examiners may apply a narrow interpretation to “readily resolved” and apply a broad interpretation to “real doubt” to weaken the test. Such examiners may consider that any unclaimed alternatives to claimed features that are included in the description satisfy the above test, and so may require description amendments similar to those that have been required before G1/25. In addition, as was the case with the decision that resulted in this referral to the EBoA, an opponent in opposition and appeal proceedings may seek to revoke a competitor’s patent that has been judged as novel and inventive, by arguing strongly that any inconsistency results in an “incompatibility” or that the inconsistency causes “non-compliance” with one or more of the requirements of the EPC.

Practical outcome

Before G1/25, examiners would often require the description to be amended to label any embodiment clearly not falling within the claim scope as explicitly not being part of the claimed invention, as well as require any feature included in an independent claim to not be described as optional within the description. Making such amendments, whilst ensuring the EPO’s strict requirements for added matter were met, could be time consuming for patent professionals, and result in corresponding legal costs for applicants. Many of these description amendments did not affect the claim scope under the established principles of claim interpretation and so appeared wholly unnecessary.

Allowing claim interpretation to resolve any apparent inconsistency should prevent examiners from continuing to insist on such description amendments. Of course, it remains to be seen how consistently examiners will interpret this decision.

In addition, before G1/25, an OD or a BoA could require the description to be amended in a similar way to that required during examination proceedings and, whilst opponents might have responded by arguing that any amendments filed should not be accepted, such arguments tended to focus only on added matter. Following G1/25, opponents are arguably in a stronger position since, even if they do not win on novelty or inventive step, they have additional grounds to attack any amended description filed. We can expect lengthy debates in high value opposition and appeal proceedings regarding claim interpretation in view of an amended description and the meaning of “incompatibility”, “readily resolved”, “real doubt” and “non-compliance”.

As with examination proceedings, an OD or BoA may apply the principles of claim interpretation outlined in G1/24 to resolve any apparent inconsistency and hence adopt a more lenient approach to description amendments, but pressure from opponents may lead to a divergence in outcome between different Divisions or Boards. It is also possible that this Decision will reach beyond the EPO with description amendments potentially being cited as amending claim scope during litigation due to file wrapper estoppel, or in influencing claim construction in corresponding US cases.

To conclude, whilst an acknowledgement that the description need not be amended for verbatim consistency with the claims is welcome in principle, it remains to be seen whether G1/25 will materially reduce the burden of description amendments, or whether it will give rise to fresh areas of contention concerning claim interpretation and the assessment of alleged inconsistencies.