G 1/24: Preliminary opinion regarding referring to the description and figures when interpreting the claims

It is a truth universally acknowledged in European patent litigation that the scope of the claims should be interpreted in light of the description (in accordance with the Protocol on the Interpretation of Article 69 EPC). However, since the EPO is not itself generally concerned with litigation, this approach may not be consistently applied during proceedings there. An inevitable result of this is that patent claims may effectively have different scopes depending on whether they are undergoing prosecution/opposition, or whether they are in litigation. This is the background to the pending referral G 1/24 to the EPO's Enlarged Board of Appeal (EBA). Now, the EBA has issued its preliminary opinion ahead of the oral proceedings scheduled for 28 March 2025.

The referral, from appeal T 0439/22, originates from an opposition to European patent No. 3076804, relating to a “heat not burn” smoking device. Claim 1 of the opposed patent recites a rod of an “aerosol-forming substrate compris[ing] a ‘gathered sheet’ of aerosol-forming material circumscribed by a wrapper”.

The opponent argues that claim 1 of the patent lacks novelty over prior art describing a rolled sheet of tobacco. While the opponent acknowledges that the term “gathered sheet” read in isolation would imply a sheet provided with folds, they argue that the term should be interpreted more broadly in view of a definition provided in the description that a “gathered sheet” means a sheet of tobacco that is “convoluted, folded, or otherwise compressed or constricted substantially transversely to the cylindrical axis of the rod”.

The Board of Appeal identified two “strands” of case law when it comes to using the description to interpret the claims: a first approach (applied by the Opposition Division in this case) in which the description and drawings should not be considered when interpreting a claim that is otherwise clear, and a second approach in which the description and drawings may be considered under certain circumstances.

The second approach has previously been found to have legal basis in Article 69(1) EPC, and the accompanying Protocol, which says that the description and drawings shall be used to interpret the claims when determining the extent of protection conferred by a European patent or application (i.e., for use by the national courts and the UPC). One of the questions the EBA has been asked to consider is, therefore, whether Article 69 EPC is indeed also to be applied in the assessment of novelty and inventive step in proceedings before the EPO.

In full, the questions that have been referred to the EBA are as follows:

1. Is Article 69 (1), second sentence EPC and Article 1 of the Protocol on the Interpretation of Article 69 EPC to be applied to the interpretation of patent claims when assessing the patentability of an invention under Articles 52 to 57 EPC?
2. May the description and figures be consulted when interpreting the claims to assess patentability and, if so, may this be done generally or only if the person skilled in the art finds a claim to be unclear or ambiguous when read in isolation?
3. May a definition or similar information on a term used in the claims which is explicitly given in the description be disregarded when interpreting the claims to assess patentability and, if so, under what conditions?

In its initial view, the EBA has observed that questions 1 and 2 are admissible, while question 3 is inadmissible.

In its preliminary opinion on question 2, the EBA says that it considers that the description and figures can be referred to in the course of claim interpretation.

In addition, the EBA acknowledges that, whether or not Article 69(1) EPC provides the legal basis for the principles that are to be applied when interpreting the claims in proceedings before the EPO, it is important that a uniform approach to claim interpretation be applied in pre- and post-grant proceedings before the EPO and in proceedings before the courts of the EPC contracting states and the UPC.

Many observers had hoped that the EBA would also consider how the answers to the above questions might impact the EPO's requirement that the description of a European patent application be adapted to comply with the claims. Indeed, the President of the EPO has suggested that the referral should be broadened to consider this point, since Boards of Appeal have similarly diverged on whether Article 69(1) EPC provides the legal basis for this requirement. However, the EBA appears (so far) not to be considering this.

It is clearly imperative that approaches to the interpretation of claims be applied consistently, both to provide legal certainty to patentees, and to enable patent attorneys to draft applications with confidence. Despite this, the argument over the principles behind these questions dates back to the founding of the EPO! Based on the preliminary opinion, it appears that the EPO are going to make the right decision here, even if they are apparently avoiding answering the third question. 

We therefore await the hearing in March with great interest!