G 1/24 - How to interpret claims when assessing patentability

The long-awaited decision on G 1/24 was released yesterday. This decision affects the prosecution of every single patent application at the EPO, so it is little wonder that it has been followed with so much interest.

Background

A more complete summary of the case can be found in this article written by my colleague, but the main facts are below.

European patent No. 3076804 relates to a vaping device which can apply heat without igniting a substrate/material (e.g. tobacco). Claim 1 of the patent recites that the “substrate comprises a gathered sheet”. The term “gathered sheet” is well known in the field of smoking devices, but the description of the granted patent gave the term a broader definition. 

The patent was opposed on the grounds of a lack of novelty, with the opponent arguing that “gathered sheet” should be interpreted according to the broader definition in the description (which would result in claim 1 lacking novelty over a piece of prior art). The patentee countered that the claims should be interpreted in isolation and so, “gathered sheet” should be interpreted according to the narrower definition known in the field of the invention. 

The Opposition Division found in favour of the patentee, and so the opponent filed an appeal. The Board of Appeal identified diverging lines of case law when interpreting the claims during prosecution of an application, with either Article 69 EPC and Article 1 of the Protocol on the interpretation of Article 69 EPC, or Article 84 EPC being used as basis. 

Legal basis

Article 69 EPC

This article governs the scope of protection of a European patent or application and is commonly used in national courts for infringement proceedings. The article and the protocol in its interpretation ultimately state that the scope of protection should be determined in light of both the claims and the description and drawings. 

Article 84 EPC

This article introduces the requirement for a claim to be clear when read in isolation of the description and drawings, and is used during the assessment of the patentability of a patent application. 

Referral

Based on the legal basis, there appears to be a contradiction in how claims should be interpreted, with some decisions interpreting the claims using the description and drawings, while other decisions interpreted the claims in isolation (unless the claim was considered to be unclear to the skilled person, in which case the description and drawings were consulted). 

As a result of the diverging lines of case law, the Board of Appeal referred the following three questions to the Enlarged Board of Appeal (EBoA):

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?

Decision

Question 1

Faced with the above two possible legal bases for claim interpretation during the assessment of patentability, it was interesting that the EBoA decided that, “neither Article 69 EPC and Article 1 of the Protocol, nor Article 84 EPC are entirely satisfactory as a basis for claim interpretation when assessing patentability” (point 6). 

Reasoning for why neither basis is suitable was provided. At point 7 of the decision, the EBoA stated that, “Article 69 EPC and the Protocol are arguably only concerned with infringement actions before national courts and the UPC”. Meanwhile, at point 8 of the decision, the EBoA states that, “Article 84 EPC addresses the content of the patent application and is formal in nature, does not mention the invention and provides no guidance on how to interpret claims”. Therefore, neither Article is suitable to act as a legal basis for how to approach claim interpretation when assessing patentability. 

As a result, the answer to question 1 is a resounding “No”. Fortunately, the EBoA provides further guidance on how claims should be interpreted when assessing patentability.

The EBoA considered the case law of the Boards of Appeal, and noted that even though there is a difference in whether Article 69 EPC or Article 84 EPC is used as basis for claim interpretation, the applied principles are not affected. Point 12 of the decision lists the principles extracted from the case law of the Boards of Appeal as follows:

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.

At point 13 of the decision, the EBoA states that the first principle is a settled point, while it is the second principle that has given rise to the diverging case law, and which corresponds to the second question referred to the EBoA.

Question 2 

At point 14, the EBoA states that it agrees with the above second principle and, “is thus rejecting the case law of the Boards that sees no need to refer to the descriptions and drawings when interpreting a claim, unless the claim is unclear or ambiguous.”

In other words, the answer to question 2 above is that “the description and any drawings are always referred to when interpreting the claims, and not just in the case of unclarity or ambiguity” (point 18).  

The reasoning for this decision is that to refer to the description only in cases of unclarity or ambiguity, "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" (point 15). 

Following the practice of national courts and the UPC makes sense and is in-keeping with the harmonisation philosophy behind the EPC. 

Question 3

The EBoA decided that question 3 was inadmissible, as it considers the question to be encompassed by question two. 

Order

The order is very similar to the extracted principles that the EBoA agreed with and states the following:

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.

Discussion

The above decision, even if not cited, will underpin the future of claim interpretation for all patent applications at the EPO, that is, for the purposes of determining patentability. 

Point 20 of the decision highlights that claims should still be amended if they are found to lack clarity, but this decision may raise the threshold for a clarity objection to be raised. 

However, the decision could also have negative ramifications for description amendments. There has been an ongoing back and forth on whether the description has to be amended to comply with the claims intended for grant in a European application. Such amendments can involve deleting or excluding embodiments that are no longer covered by the scope of the claims. Such amendments are often time-consuming, and therefore costly, to make. The latest decision on the matter (T0056/21) in October 2024 found that there was no legal basis to require such amendments. However, G 1/24 could now be used to argue that as the description and drawings are to be used to interpret the claims, they should not contain information which could cause a misinterpretation of the claims. G 1/24 only discusses referring to the description and drawings to interpret the claims, not the other way round. Therefore, it is unclear if such a bilateral dependence was intended by the EBoA.

Question 3 was considered encompassed by question 2, so no explicit answer was provided to it. Based on the answer to question 2, the implicit answer to question 3 is that a definition in the description takes precedence over the standard definition of any term. However, as the Decision only states that the description must be “consulted to interpret the claims”, there is at least some ambiguity as to how the description should be taken into account once consulted. It can be seen that careful drafting continues to be of primary importance because any definitions in the description could be used to interpret the meaning of the claims in an unintended manner. A skilled patent attorney will continue to carefully consider whether terms used in the description require further clarification, especially if those terms are used in the claims. Careful use of fall back positions, such as defining narrower terms, will continue to be important.

Another interesting note is the consideration of the case law of the UPC and the confirmation that the UPC has taken a similar approach to claim interpretation (point 19). From this, the EBoA might be suggesting that the EPO should follow a consistent approach to the UPC. 

It is clear that this decision will have a lasting impact on patent prosecution in Europe, and we at Marks and Clerk will be watching it closely.

The Enlarged Board today issued its decision in case G 1/24. It concluded that the claims are the starting point and the basis for assessing the patentability of an invention, and that the description and drawings must always be consulted to interpret the claims for this assessment.

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