Most people understand that the claims of a patent are used to interpret the scope of the protection of invention being sought by the inventor or applicant.
One recent decision of the EPO (European Patent Office), known as G1/24, now sheds light on how they should be interpreted. This is a key decision – as perhaps surprisingly, there were differing views leading up to this point, as we’ll explain. But before we dive into the detail, it’s worth stepping back to explain what the claims are, what they mean for the invention, and how they relate to getting a patent – and, of course, any infringement.
A Bit of Background
To get a patent granted for your invention, you need to fully describe your invention and how it works in the description, provide at least one diagram (figure) and at least one claim, all in what’s known as a patent ‘specification’. Wherein the technical description is meant to explain the invention in the context of the world around it, and the claim is then meant to define the scope of protection. For example, in your description, you could explain how well your new car maneuvers going round corners, or in wet weather conditions, with its new tires, but the invention is specifically to do with the material used in the tires.
As such, you wouldn’t want to claim the wheel, the engine or the brakes of the car, as these are not new or inventive. So, your claim would therefore be directed towards the use of the new material (as well as how it is manufactured) to make car tires.
Simple enough in this case may be, but in more complex cases, including those in the fields of biology, life sciences or chemistry, it isn’t always that clear cut what the actual invention is (and therefore isn’t) for the assessment of novelty and inventive step. It is a separate matter how those claims should be interpreted for infringement purposes, although technically, this interpretation should be one and the same.
In general practice and in most jurisdictions around the world, including the EPO, it is generally accepted that the description and figures should be used to help interpret the claims, but how, and by how much, is usually defined by a nation’s jurisprudence (case law) and what this means for a European Patent was the debate in this case.
For example, at one extreme, claims could be interpreted totally in isolation, without any reference to the description whatsoever. At the other extreme, the whole patent application could be used as its own dictionary, such that the description can comprise a glossary, defining claim terms that are contrary to their normal meaning. For example, what would happen if you defined that, in the context of your specification, up is down and long is short? How should a claim be interpreted then?
Thus, a term in a claim that is otherwise clear may be given a broader, narrower, or entirely different interpretation as a result of what is disclosed in the description or figures. There is also an alternative view, where the description should only be considered when there is ambiguity in a claim term: should all claim terms be clear they are given their normal meanings and the description is thus ignored.
The Case In Hand
The appeal case leading to this decision, T 0439/22, has claims that contain the term “gathered sheet”, which in the patent application is used to describe a tobacco sheet in an aerosol generating device. The original Appeal Board took the view that “gathered sheet” was a well-known term in the technical field with an accepted meaning, but the description of the patent specification set out further definitions that were broader. So, should this be a case where the description can act as its own dictionary such that the broader meaning should be given to the term “gathered sheet” when interpreting the claims?
The Law
Article 84 EPC relates to a formal requirement for claims and simply says, “The claims shall define the matter for which protection is sought. They shall be clear and concise and be supported by the description.” The Implementing Regulations to the EPC provide further guidance on the form of the claims, but nothing further is said regarding claim interpretation.
Article 69 EPC (and its associated Protocol on Interpretation), relates to infringement in national courts and the UPC, and states that the extent of protection of a granted European patent is “determined by the claims, and that the description and drawings shall be used to interpret the claims”. However, this Article refers to a European patent and case law diverges on whether Article 69 should also apply when considering patentability (ie novelty and inventive step).
Thus, the following three questions were referred to the Enlarged Board of Appeal:
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Is Article 69(1), second sentence EPC and Article 1 of the Protocol on the Interpretation of Article 69 EPC to be applied on the interpretation of patent claims when assessing the patentability of an invention under Articles 52 to 57 EPC?
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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?
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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 Decision:
Question 1
Unsurprisingly, the Enlarged Board of Appeal (EBoA) confirmed that neither Article 69 EPC (and the Protocol), nor Article 84 EPC, are entirely satisfactory as legal basis for claim interpretation when assessing patentability.
The EBoA also noted that Article 69 EPC and the Protocol are arguably only concerned with infringement actions before national courts and the Unified Patent Court (UPC). Their conclusion was based on the wording of Article 69 EPC and the Protocol, their drafting history, and their position in the EPC. Quite right, as this is a long established position in the law.
The EBoA also considered Article 84 EPC when considering question 1 above. They noted that the Article is formal in nature and that it neither mentions the invention nor provides guidance on how to interpret the claims. Again, very true.
Thus, the EBoA answered question 1 in the negative, establishing that there is no legal basis within the EPC for claim interpretation when assessing patentability.
However, the EBoA clarified that this ‘does not imply a need to develop entirely new principles for claim interpretation‘, and the EBoA further emphasized that its answer to question 1 does not alter the established principles to be applied when interpreting claims in practice. In particular, the EBoA highlighted that the existing case law developed by the Boards of Appeal offers ‘valuable guidance on this matter’. From this body of case law, the EBoA identified the following key principles:
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The claims are the starting point and the basis for assessing the patentability of an invention under Articles 52 to 57
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The description and any drawings are always referred to when interpreting the claims, and not just in the case of unclarity or ambiguity.
Whilst the first principle was considered a “settled point” by the EBoA, they indicated this was not the case for the second principle – because of the diverging case law.
Question 2
The EBoA rejected the case law that says the descriptions and drawings are only to be considered when a term in a claim is unclear or ambiguous. They believe that such case law
“is contrary to the wording, and hence the principles, of Article 69 EPC. It is also contrary to the practice of the national courts of the EPC states and to the practice of the UPC”.
They stated that:
“it a most unattractive proposition that the EPO deliberately adopt a contrary practice to that of the tribunals that are downstream of its patents”.
The EBoA noted that their findings are compatible with the UPC’s existing case law, citing the UPC Court of Appeal’s decision in UPC 252/2023 (NanoString Technologies vs. 10x Genomics).
To conclude the EBoA confirmed:
“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.”
Question 3
The EBoA found question 3 to be inadmissible. This is because the question related to whether a definition of a term in the description can be disregarded when interpreting the claims and so was deemed to be covered by question 2.
It therefore followed from the answer to question 2, that question 3 would be answered in the negative also. Since the description must always be consulted and a term in the description should not be disregarded when interpreting the claims.
Conclusion
Overall, the decision is welcomed, as it provides more certainty for all parties. There was also a clear and apparent aim by the EBoA to prevent inconsistencies between the extent of protection granted by the claims (ie for infringement purposes) and how the claims should be interpreted for determining patentability (novelty and inventive step). It was also very clear that the EboA also wanted to maintain, as well as further develop, a level of harmonisation between the EPC and the UPC.
With this being such a key decision from the EBoA, we expect there to be a corresponding update to the EPO Guidelines for Examination, expected in 2026 and which we will report on separately.
If you wish to understand this decision further, or discuss claim interpretation with one of the team then do reach out to any one of us.