Context: The European Patent Office (EPO) and the Unified Patent Court (UPC) are independent from each other in many ways, but the UPC has appellate jurisdiction over the Unitary Patent (UP) and both are bound by the European Patent Convention (EPC), though the UPC also has to apply European Union law, which is not binding on the EPO.
What’s new: Today the Enlarged Board of Appeal (EBA) of the EPO has rendered one of its most important decisions ever, and it is the first major EPO decision to harmonize a key legal standard applied by the EPO and the UPC. In case no. G 0001/24 (appeal no. T 0439/22-3.2.01) relating to EP3076804 (“Heated aerosol generating article with thermal spreading wrap”; a vaping patent), the EBA has spelled out the following claim construction standard:
The claims are the starting point and the basis for assessing the patentability of an invention under Articles 52 to 57 EPC.
The description and drawings shall always be consulted to interpret the claims when assessing the patentability of an invention under Articles 52 to 57 EPC, and not only if the person skilled in the art finds a claim to be unclear or ambiguous when read in isolation.
Direct impact: The first sentence is non-controversial, but there were divergent schools of thought on the second part. Today’s decision closes the door to arguments according to which the description and drawings should be ignored because a claim element is allegedly unambiguous from the perspective of a skilled person.
Wider ramifications: The decision notes that it is desirable for the EPO to align its legal standard with the “downstream” (courts dealing with its patents in subsequent proceedings, mostly infringement lawsuits), specifically also mentioning the UPC. The above guidance is materially consistent with what the UPC’s Court of Appeal (Coa) spelled out on February 26, 2024 in 10x Genomics v. NanoString (PDF):
The patent claim is not only the starting point, but the decisive basis for determining the protective scope of a European patent under Art. 69 EPC in conjunction with the Protocol on the Interpretation of Art. 69 EPC.
The interpretation of a patent claim does not depend solely on the strict, literal meaning of the wording used. Rather, the description and the drawings must always be used as explanatory aids for the interpretation of the patent claim and not only to resolve any ambiguities in the patent claim.
The fact that more than 30 amicus curiae briefs were submitted shows the fundamental importance of the question. Of course, the President of the EPO also made a submission to the EBA, as did the parties.
As discussed further below, the standard in the U.S. depends on the type of proceeding.
The EBA is the EPO’s highest interpretive authority, as is the CoA for the UPC, apart from questions of EU law that may be put before the European Court of Justice (ECJ). With today’s decision, the broad lines of what role the claims, the description and the drawings play in claim construction have been aligned between the UPC and the EPO.
The UPC’s CoA elaborated on this question even more in its 10x v. NanoString (for the avoidance of doubt, 10x was the plaintiff-appellee and NanoString the defendant-appellant) decision:
This does not mean that the patent claim merely serves as a guideline but that its subject matter also extends to what, after examination of the description and drawings, appears to be the subject-matter for which the patent proprietor seeks protection.
The patent claim is to be interpreted from the point of view of a person skilled in the art.
In applying these principles, the aim is to combine adequate protection for the patent proprietor with sufficient legal certainty for third parties.
These principles for the interpretation of a patent claim apply equally to the assessment of the infringement and the validity of a European patent.
None of that conflicts in any way with today’s EBA decision. If anything, it adds color.
Today’s harmonization is important, yet does not mean that claim construction is going to be less bitterly contested going forward. In the end, there still is plenty of room for scenarios in which the description and drawings will be used to argue a narrower claim scope than what the claims literally say as well as for scenarios in which someone (be it the patentee in order to capture more infringements or someone challenging the patent’s validity) will try to broaden the scope of a claim beyond its literal meaning. The only type of argument to be rejected on this basis is that the clarity of the claim language renders the description and drawings irrelevant for claim construction purposes.
Questions referred to EBA
Technical Board of Appeal (TBA) 3.2.01 had before it an appeal by a third party (Yunnan Tobacco) of the Opposition Division’s rejection of its opposition to the patent at issue, which is held by Philip Morris. The novelty of a challenged claim hinged on the claim construction standard: in one case the claim was broader (but not unreasonably broad from a technical vantage point) and invalid, and in the other it was narrower and valid. It was, in fact, just about one claim term: ““gathered sheet.”
The TBA then referred to the EBA the following questions of law:
- 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?
- 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?
- 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?
The EBA did not answer the third question because it held it inadmissible here, as it is not necessary to answer it in order to enable the referring TBA to decide the appeal. The EBA and actually provided enough guidance through its answer to question 2.
How the EBA reached its conclusions
In terms of statutory interpretation, question 1 was about whether claim construction for a patentability determination under Art. 52-57 EPC would be guided by Art. 69 EPC and Art. 1 of the Protocol or by Art. 84 EPC:
- Art. 69 EPC in conjunction with Art. 1 of the Protocol stresses the importance of the claims, but also gives an important role to the description and the drawings.
- Art. 84 PC suggests that claims should be self-sufficient.
In some past cases where the legal standard was not outcome-determinative, the EBA actually took divergent views (G 2/88 and G 6/88 are mentioned as examples of EBA decisions saying that Art. 69 EPC applies, while G 2/12 “identified Article 84 EPC as the legal basis”).
The EBA now holds that neither of those prior approaches is the best way forward. The Art. 69 school of thought is focused on infringement proceedings (which the EPO itself does not handle). But Art. 84 is just prosecution-related guidance on how to draft a patent claim. Therefore, in formal terms the answer to question 1 (whether Art. 69) applies would simply be “no” — but the EBA didn’t want to leave it at that. Instead, it went on to provide further guidance based on prior EPO case law:
1) The claims are the starting point and the basis for assessing the patentability of an invention under Articles 52 to 57 EPC.
2) The description and any drawings are always referred to when interpreting the claims, and not just in the case of unclarity or ambiguity.
Item 1 above (claim are starting point and basis) alread was settled law at the EPO prior to today’s decision. The second part, however, required harmonization.
The EBA concluded that consulting the description only where there is an ambiguity or lack of clarity was contrary to the wording and principles of Art. 69 EPC, but also “finds it a most unattractive proposition that the EPO deliberately adopt a contrary practice to that of the tribunals that are downstream of its patents.” That includes, of course, the UPC as an ever more important court and, somewhere down the road, the exclusive court to rule on EPO-granted patents.
Apart from harmonization, the EBA also views this as a logical outcome:
17. […] The finding that the language of a claim is clear and unambiguous is an act of interpretation, not a preliminary stage to such an interpretative act.
This does not mean that Art. 84 EPC becomes less important now. Instead, the EBA stresses “the importance of the examining division carrying out a high quality examination of whether a claim fulfils the clarity requirements of Article 84 EPC.” If there is a lack of clarity, a claim must be amended. And that is what the President of the EPO also said in his submission.
U.S. approach is context-sensitive
While the EPO and the UPC now have a harmonized approach that applies to patent examination, opposition (the only type of post-grant review available from the EPO; there is no inter partes review equivalent for patents that are out of the opposition window) and infringement proceedings.
In the U.S., the description and drawings are not necessarily consulted as claim terms may be deemed unambiguous and clear. The standard depends on the procedural context:
- USPTO examiners must apply the broadest reasonable interpretation (BRI) standard (MPEP link).
- In inter partes reviews and infringement litigation, the Phillips v. AWH standard (a 2005 decision by the Federal Circuit) applies. The result is often the plain and ordinary meaning of a claim term, but additional sources (description, drawings, prosecution history and even extrinsic evidence such as expert testimony and dictionaries may be considered.
- The PTAB will also give “appropriate weight” to prior claim construction decisions by Article III courts or the United States International Trade Commission (USITC, or just ITC).
This means claim construction is a more context-sensitive exercise in the U.S., and it is also a more formal one with a separate hearing (Markman hearing) in federal courts and the ITC, further to which an alternative wording will be determined for any claim elements that are not considered to have their plain and ordinary meaning.
More harmonization between EPO and UPC to come
Going back to the European landscape, it is a safe assumption that there will be further convergence between EPO and UPC case law. And this goes both ways: various UPC decisions have been deferential to EPO case law, including that the Munich Local Division (LD) became the first division of the UPC’s Court of First Instance (CFI) to explicitly adopt the EPO’s problem-solution approach to the inventive-step analysis (April 4, 2025 ip fray article). It will obviously depend on what the CoA will decide in that regard.