G1/24: EPO Enlarged Board to extinguish uncertainty on patent claim interpretation

G1/24: EPO Enlarged Board to extinguish uncertainty on patent claim interpretation

The EPO Enlarged Board of Appeal has been asked to consider whether or not, and to what extent, the claims of a European patent can be interpreted using the description and figures. It is currently an open question as to what the legal basis is for construing patent claims and there is disharmony in EPO case law as to how the claims should be interpreted. Key considerations being put to the Enlarged Board of Appeal include whether the description and figures can only be used for claim interpretation when the claim wording is found to be unclear or ambiguous, and whether the patent may serve as its own dictionary to redefine common terms in the art.
Clarity on these points would provide welcome guidance on how to interpret the scope of protection provided by European patents.

What led us to this referral?

Back in April we reported that the EPO Technical Board of Appeal would ask the Enlarged Board of Appeal whether content in the description and figures should be used to interpret the claims (in T 439/22, Board 3.2.01). This is based on disharmony in the way that the EPO Boards of Appeal have considered this to date, with divergence between different cases evident in the existing body of case law. The referral has now been made, in which the Enlarged Board have been asked hopefully to harmonise the position.
The appeal concerns a decision by the opposition division to uphold European Patent No. 3076804 owned by Philip Morris Products S.A. The patent relates to so‑called "heat-not-burn" tobacco products and central to the decision is the interpretation of the term "gathered sheet". If the term were to be given its usual meaning in the art then the Board may find the claim novel. However, if the same term were to be given a broader interpretation in view of the disclosure in the description then the patent may be found to be invalid in view of the prior art.

Referred questions

 The Board believe that the case law of the Boards is divergent on the following three questions, which are considered to be interrelated but not dependent on each other:

  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?

Article 69(1) EPC sets out that “The extent of protection conferred by a European patent or a European patent application shall be determined by the claims. Nevertheless, the description and drawings shall be used to interpret the claims.
The Protocol on the Interpretation of Article 69 EPC highlights that there is a balance to be adopted when interpreting the extent of protection, between (a) the claims being given their purely literal meaning; and (b) the claims serving only as a guideline, with the extent of protection being based on a contemplation of the overarching invention, considering the description and drawings (as well as the claims).
Following these, therefore, the description and drawings/figures should be at least partially relevant to determining the extent of protection. However, the referring Board recognises that there is a strong line of case law that considers that Article 69 EPC, and Article 1 of the Protocol on the Interpretation of Article 69 EPC should be applied exclusively to considerations of added subject matter. Another line of case law postulates that Article 69 EPC, and Article 1 of the Protocol on the Interpretation of Article 69 EPC should be applied to the whole realm of the EPC, including to considerations of novelty, inventive step and sufficiency of disclosure.

  1. 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?

Here again the Board identifies two distinct lines of case law, as exemplified by decisions T 1473/19 and T 169/20. In T 1473/19, the Board held that the description should be taken into account when interpreting claim terms, even if the wording appears clear. Conversely, in T 169/20, the Board considered the description should only be relied upon for interpreting claims in exceptional cases where the claimed subject-matter or technical context needs clarification. If the skilled person considers the wording of a claim to be clear on its face, especially when the term has a well-established meaning in the relevant field, then consulting the description for interpretation is deemed unnecessary and unjustified.

  1. 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 the Board’s view, some decisions emphasise the autonomy of patents to define the meaning of terms used in patent claims and the need to read these terms in the context of the whole content, taking into account what is achieved by the invention. Other decisions, however, underline that the support of the description should at least not be used for restricting or modifying the subject-matter of the invention beyond what a skilled person would understand when reading the wording of the claims.
All three of these questions are therefore based on a body of case law which provides somewhat conflicting precedential influence on the interpretation of patent claims. Hopefully, G1/24 will harmonise the approaches here.
The next key step in the procedure will be for the Enlarged Board of Appeal to decide whether the referral is admissible. If it is, parties can advance their positions in writing, a hearing will be conducted and then the Enlarged Board will eventually issue a decision setting out their stance. This decision could include answers to the three questions above, but they also could elect to reframe these and answer entirely different questions on the interpretation of patent claims. It therefore remains to be seen how much guidance, clarity and harmony will be given with this Enlarged Board referral.

Referrals to the Enlarged Board can sometimes lead to stays on cases currently in examination and opposition proceedings in which the decision depends entirely on the outcome of the referral to the Enlarged Board. For the present referral, however, the EPO has indicated that examination and opposition proceedings should continue.
We will await the Enlarged Board of Appeal’s decision with interest and will report further as the matter progresses. If you have any questions or would like to discuss the potential impact on your cases, please contact Sophie EvansJames Snaith or your usual Kilburn & Strode advisor.


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