Wrestling with G1/24 – How should the claims be interpreted in view of the description?

In G1/24, the Enlarged Board of Appeal (EBA) codified how claims should be interpreted for assessing patentability: in consultation with the description. However, the decision was light on how, in practice, this should be carried out. Wrestling with that task has thus largely fallen on the shoulders of the members of the Boards of Appeal.

Here we explore how G1/24 has been implemented in subsequent Boards of Appeal decisions and the effects this may have on patentees and third parties moving forward. In the decisions reviewed, the Boards of Appeal have still given primacy to the claims, despite interpreting the claims in light of the description where terms were given narrower definitions than their normal meaning. It remains to be seen whether this is a trend of simply the result of the facts of each case.

G 1/24 

As set out in our earlier article, G 1/24 relates to how the claims of patents are to be interpreted by the Boards of Appeal and, by extension, all organs of the European Patent Office.

The headnote of G 1/24 is as follows:

“The claims are the starting point and the basis for assessing the patentability of an invention…The description and drawings shall always be consulted to interpret the claims when assessing the patentability of an invention…and not only if the person skilled in the art finds a claim to be unclear or ambiguous when read in isolation.” 

In essence, G 1/24 sets out that the description is always to be referred to when interpreting the claims and not just in the case of unclarity or ambiguity.

The impact of G 1/24 at the practical level is only now beginning to be felt. In particular, Technical Boards of Appeal are having to grapple with the meaning of the word “consulted” in the order.

To date a number of decisions have cited G1/24, namely T0641/22; T0697/22; T1867/22; T2063/22; T2116/22; T0367/23; T0744/23; T0933/23; T1465/23; T1561/23; T1999/23 and T0161/24.

Below we explore the key decisions T1561/23, T1999/23, T0161/24 and T1465/23 in more detail.

In G1/24, the Enlarged Board was keen to set out that it is desirable for the European patent system to have a common way of interpreting the claims. The UPC set out its stall fairly early in its lifetime with NanoString Technologies v Genomics (NanoString). This decision was referred to by the Enlarged Board of Appeal. Before discussing the Board of Appeal decisions we will first briefly recap what the UPC Court of Appeal said in NanoString.

UPC approach – NanoString

The question of how the claims should be interpreted in light of the description has been considered by the UPC Court of Appeal in NanoString Technologies -v- Genomics (UPC_CoA_335/2023). This first ever substantive UPC Court of Appeal decision issued in February 2024.

The decision concerns 10x Genomics’ patent EP 4 108 792, which relates to the in situ detection of analytes in cell or tissue samples mounted on a solid support. The patented method allows for the detection of a plurality of analytes, which is desirable as test samples are often precious and those analysing them may not know exactly what to look for in a particular sample.

At first instance, 10x Genomics was granted a preliminary injunction against NanoString. The Munich local division were happy that the patent was infringed and that the patent was novel, inventive and sufficiently disclosed.

On Appeal, the patent’s validity was re-assessed – with a particular focus on claim interpretation. In its decision, the Court set out that:

“The patent claim is not only the starting point, but the decisive basis for determining the protective scope of a European patent.”

Consequently, according to the UPC Court, the interpretation of the claims does not just depend on the literal wording of the claims, but 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”. This interpretation is considered to follow from Art. 69 EPC and the Protocol on its Interpretation. To further explain its meaning, the Court set out that this “does not mean that the patent claim merely serves as a guideline and 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” and also that the claim should be interpreted from the view point of a person skilled in the art.

In this decision, the Court of Appeal appear to be trying to strike a balance in terms of claim interpretation: “In applying these principles, the aim is to combine adequate protection for the patent proprietor with sufficient legal certainty for third parties”. The Court also said that this approach should apply equally to the assessment of infringement and validity of a European patent. This approach mirrors the “purposive construction” approach used by English courts.

Based on this interpretation, the Court of Appeal disagreed with the decision of the Court of first instance that one of the steps in the claim excluded detection and incubation being carried out in cycles. Therefore, the Court of Appeal was not convinced that the patent was valid due to inventive step concerns associated with this interpretation of the claims. Therefore, they concluded that there was not sufficient basis for the issuance of a preliminary injunction.

Board of Appeal cases

T1561/23

The first decision to interpret G1/24 was the Board of Appeals decision in T1561/23 which was an appeal from the Examining Division refusing EP Application 17720035.9 (published as EP3446216 (EP’216)) directed towards methods for executing “additional functions” within real-time environments that perform “tasks” such as production plants.

A key issue to be decided in the Appeal was whether D5, which disclosed a real-time environment performing both “co-operative tasks” and “pre-emptive tasks” anticipated Claim 1. To make this determination, “tasks” and “additional functions” needed to be interpreted.

The Applicant Appellant argued that Claim 1 indicated that “tasks” and “additional functions” were distinguishable by use of the different terminology and that the description (with reference to G1/24) indicates that “tasks” have a fixed runtime (such as control of actuators or sensors), whereas “additional functions” have an indefinite runtime (such as vision systems or condition monitoring). Accordingly, it was argued, D5 did not anticipate Claim 1 because both the “co-operative” and “pre-emptive” tasks had fixed runtimes meaning D5 failed to disclose “additional functions”.

The Board disagreed and found that “tasks” and “additional functions” were indistinguishable. The description failed to indicate how “additional functions” were fundamentally different to “tasks” and both are intended to have (as far as possible) predictable runtime behaviour.

With regards to G1/24, the Board noted that:

“G1/24 does not define what it means to consider the description and drawings…[and] does not even explicitly require that the definition of a term from the description must be used for interpretation of a claim…In the present case….consideration [of the description] would not justify a narrower interpretation of the wording of the claims”

Claim 1 of the Main Request was thus deemed not novel (with the only Auxiliary Request found to lack an inventive step) and the refusal was upheld.

T 1999/23

T 1999/23 relates to an Appeal of an Opposition Division decision concerning EP 3086087 (EP’087). At its crux, T1999/23 relates to whether a technical term of art used in the claims should be (re-)interpreted in light of a contrasting definition in the description.

The main substantive issue was whether Claim 1 was novel over D23 (EP 2975360) which, in turn, rested on the interpretation of the term “excitation area” in the Claims.

[0008] of EP’087 defines the term “excitation area” as “the cross-sectional area of the excitation light when in focus”. In contrast, the Board found that the skilled person in the technical field would understand the term “excitation area” to mean the cross-sectional area of the excitation light on the specimen independently of the distance between the specimen and the claimed photothermal device.

Referring to G 1/24, the Board acknowledged that the description is to be used when interpreting the claims. However, they concluded that this does not detract from the principles of established case law that “the description cannot be relied on to read into the claim an implicit restrictive feature not suggested by the explicit wording of the claim” (see section II.A.6.3.4 of the Case Law Book). They also set out that this reasoning is not, in its view, in conflict with G1/24 as the Enlarged Board emphasised that interpretation should begin with, and be based on, the claims.

Therefore, the Board concluded that allowing a Proprietor to deviate from an established meaning of technical terminology used in the Claims would undermine legal certainty for third parties. In fact, the Board held that the Proprietor should be held accountable for the legal ambiguity they had created by inconsistently using the term “excitation area” such that “resolving this ambiguity to the detriment of the person who created it without objective necessity is in line with the principle of legal certainty and the primacy of the claims reaffirmed in decision G 1/24.” 

Consequently, the ordinary meaning of the term “excitation area” was applied and D23 was found to destroy the novelty of the Claims at issue, resulting in revocation of the Patent.

T0161/24

T0161/23 relates to an Appeal from the Opposition Division concerning EP3443155 (EP’155) directed to a woven fabric with a plurality of “loose loops” with some loops (A) “extending looser” than other loops (B).

Unlike the matter at issue in T1999/23, the terms used in the Claims had no ordinary meaning. The primary question to be answered, however, was what the terms “loose loops” and “extending looser” signified.

The Opponent Appellant (in line with the Opposition Division’s decision under appeal) argued that the description failed to provide the skilled person with a sufficient method to measure the “looseness” of a loop and determine whether A is looser than B in the real world, especially in extreme cases where both A and B may be loose to an extent and the differences in looseness may be slight such that small differences in absolute length measurements would be significant.

The Proprietor Appellant, in contrast, argued for a narrow construction, based on [0034] of the Patent. They asserted that:

1. a) “looseness” was defined by a ratio between the loop length and the distance it bridged such that absolute lengths were irrelevant,
2. b) none of the embodiments disclosed both loops A and B being “loose” such that the claim should be interpreted to be limited to embodiments where only loops A are loose, and
3. c) the skilled person, based on their common general knowledge, knew sufficient methods to measure the length of a loop or its bridging distance.

The Board disagreed with the Proprietor on all counts and dismissed the narrow construction of the Proprietor stating instead that:

4.5.1  The claims shall define the matter for which protection is sought (Article 84 EPC). The Board cannot see a legal basis to necessarily restrict the scope of the claims by statements and/or features which are only contained in the description.

4.5.2  When taking into account the description of the patent (see e.g. the headnote of G1/24) – which is not necessarily, and indeed may rarely be, limiting for the claimed subject-matter due to the primacy of the claims which may be broader than particular limited examples and explanations given in the description – there is anyway nothing in the cited passages of the description which would support the appellant’s narrower interpretation of Claim 1.

The Board thus found that both loops A and B may be “loose” and to work the invention the skilled person must be able to determine said “looseness” reproducibly and reliably in the real world (not just theoretically based on an artificially constructed schematic diagram). As such a method was neither disclosed in the Patent nor evidenced to be known in the common general knowledge, the first instance finding that the claims were insufficient was thus upheld.

T1465/23

T1465/23 relates to an Appeal of an Opposition decision relating to patent EP 3113515 (EP’515) directed to a hearing device configured to communicate with other devices. An article discussing the facts and issues T1465/23 in greater detail may be found here.

The nub of the issue before the Board was whether the plurality of novel features provided a technical effect and thus contributed to an inventive step over the closest prior art document D1. On the one hand, the Proprietor Appellant argued that the embodiments in the description (in view of G1/24) should limit the Claims to only cover embodiments that address the objective technical problem asserted in the specification (i.e. providing different levels of authentication for secure communication). On the other hand, the Opponent Appellant argued that the Claim wording, when given its broadest reasonable interpretation, did not support this effect across its full scope and thus could not be used to support a technical effect in line with G1/19.

The Board found in favour of the Opponent Appellant’s argument. Indeed, the Board stated that the description cannot override a stable and well-understood meaning and that G1/24 does not afford the Proprietor an opportunity to artificially circumvent patentability objections based on prior art by merely interpreting the claims more narrowly than is reasonable based on the ordinary meaning of the terms.

The Boards reasoning thus clearly follows from T1999/23 (which was cited by the Boards of Appeal in its decision).

Conclusions

Overall, it seems that the Board of Appeal decisions following G 1/24 have much in common. In each of T1561/23, T1999/23, T0161/24 and T1465/23 the Boards ultimately gave primacy to the wording of the claims and concluded that “consulting the description” does not mean that definitions from the description should be inserted into the claims when there is already a clearly understood meaning of these terms. The decisions cited in this article relate to a number of principles of the EPC, including novelty, inventive step and sufficiency of disclosure. Of particular interest is the decision in T0161/24, where the Board held that the definitions given in the description could not be used to narrow the meaning of the terms in the claim, meaning that a portion of the claim being insufficient, led to an overall conclusion of lack of sufficiency of the claims.

It is also of interest, that in all of these decisions, the parties have tried to use definitions from the description to narrow the meaning of the claims. It remains to be seen how the Board of Appeal in T 459/22 (the G1/24 referring decision) will grapple with the definition of the term “gathered”, where an allegedly broader definition is provided in the description.

Moreover, there seems to be some scope for divergence between EPO and UPC case law. In NanoString Technologies -v- Genomics the UPC Court of Appeal set out that the description must always be “used as explanatory aid[s]” with reference to Art. 69 EPC as basis for this conclusion. This requirement appears different to the requirement to “consult the description” set out in G1/24. We also note that G1/24 says that Art. 69 EPC does not provide unambiguous legal basis for claim interpretation at the EPO. Therefore, it seems that UPC case law is placing greater emphasis on the description than the case law being developed by the EPO Boards of Appeal, which has interpreted G1/24 as being in accordance with the primacy of the claims.

The significance of this developing area of case law is also underlined by the recent referral to the Boards of Appeal in G1/25. This relates to adaptation of the description. The first question in the referral is as follows:

“1.        If the claims of a European patent are amended during opposition proceedings or opposition-appeal proceedings, and the amendment introduces an inconsistency between the amended claims and the description of the patent, is it necessary, to comply with the requirements of the EPC, to adapt the description to the amended claims so as to remove the inconsistency.”

The second question of referral asks which ground of the EPC would necessitate such adaptation and the third question asks whether the answers to questions 1 and 2 would be different if the claims of the European patent are amended during examination proceedings.

As can be seen from the above cases, the issue of description amendment is important because the description of the patent is likely to influence interpretation of the claims in infringement and validity proceedings. In light of the developing line of case law it will be interesting to see whether there is a move from the Enlarged Board to force patent proprietors to avoid inconsistencies between definitions in the patent description and those in the claims. However, as with many recent G decisions the Enlarged Board may leave the answer to the questions open to the interpretation of subsequent Board of Appeal.

Overall, it seems that this is an area of significant interest for European patent practice. It appears that a consensus is developing among the Boards of Appeal about how G1/24 should be implemented; although this seems to differ from the approach taken by the UPC.

This article was prepared by Senior Patent Attorneys Thomas Lonsdale, and Alexandra Tyson.