6.1. Principes généraux

In T 405/24 the board agreed with the opposition division and the respondents that granted claim 1 contained added subject-matter. Feature 1.7 bore no limitation in respect of the type of "filtered packets" being "routed" to the "proxy system".

The appellant argued that "routing filtered packets to a proxy system" in the context of claim 1 was to be broadly construed, i.e. it should not be narrowly interpreted as "network-layer routing" only. Rather, it should include any kind of "sending", "forwarding" or "logging". The unit "RG1" in step #19 of Fig. 3B at the very least "forwarded" to the proxy device "PD1" those packets (comprising encrypted data) which were not "dropped" but "logged". Thus, the skilled person in the field of data communications would have understood that such "forwarding" was providing a basis for the "routing" action of feature 1.7. According to the appellant, if multiple technically sensible interpretations of a certain claim feature existed, the one which was supported by the patent description should prevail.

The board was not persuaded by the appellant’s argument. First, the board considered that even if the Order of G 1/24 (which related to assessing compliance with Art. 52 to 57 EPC only) could be extrapolated to the assessment of compliance with Art. 123(2) EPC, there was no indication in G 1/24 that "consulting" or "referring to" the description and drawings could translate into adopting a claim interpretation which ensured that the disputed feature was originally disclosed and thus necessarily fulfilled Art. 123(2) EPC. Such an approach, which according to the board inherently assumed that there may be only one "correct" interpretation of a claim feature, namely the one derivable from the original description as its intended meaning, would not lead to an objective assessment of compliance with Art. 123(2) EPC. The board did not follow the approach of T 367/20 (for the event of "mutually exclusive" interpretations) nor T 2048/22 (claim ambiguities). Rather, the board relied on the body of case law which holds that all technically reasonable interpretations of a disputed claim feature are to be taken into account when assessing compliance with Art. 123(2) EPC (see e.g. T 945/20, T 470/21, T 2034/21, T 193/22).

Second, even if, for the sake of argument, the "forwarding" of logged packets (comprising encrypted data) to the proxy device "PD1" in step #19 constituted a specific instance of the more general "routing filtered packets to a proxy system", this would still fail to justify the claimed generalisation, which also encompassed, among other things, network-layer routing of filtered packets not being necessarily logged.

Thus, the board concluded that the ground for opposition under Art. 100(c) EPC in conjunction with Art. 123(2) EPC prejudiced the maintenance of the patent as granted. The same objections applied to auxiliary requests 1 to 7 and 9 to 15. Auxiliary requests 8 and 2b were not admitted into the appeal proceedings. Since there were no allowable claim requests on file, the appeal was dismissed.

In T 1193/23 hatte die Beschwerdegegnerin (Patentinhaberin) zu verschiedenen im Anspruch 1 des Hauptantrags verwendeten Begriffen, insbesondere "Lageregelung" sowie "überprüfen" im Vergleich zu "überwachen", Bezug auf Antworten des Chatbot ChatGPT genommen..

Die Kammer merkte an, dass die Antwort von ChatGPT an sich irrelevant war, da es bei der Auslegung des Anspruchs um das Verständnis der Fachperson geht (s. auch T 206/22). Allein die allgemein zunehmende Verbreitung und Nutzung von Chatbots, die auf Sprachmodellen ("large language models") und/oder "künstlicher Intelligenz" beruhen, rechtfertigt noch nicht die Annahme, dass eine erhaltene Antwort – die auf dem Nutzer unbekannten Trainingsdaten beruhen und zudem empfindlich vom Kontext und der genauen Formulierung der Frage(n) abhängen kann – notwendigerweise das Verständnis der Fachperson auf dem jeweiligen technischen Gebiet (zum relevanten Zeitpunkt) richtig abbildet. Der Nachweis, wie bestimmte Begriffe im Anspruch eines Patents (oder einer Patentanmeldung) durch die Fachperson ausgelegt werden, kann zum Beispiel durch geeignete Fachliteratur belegt werden. Für die behaupteten unterschiedlichen Bedeutungen der oben genannten Begriffe im relevanten technischen Gebiet war kein derartiger Nachweis eingereicht worden.

Die Kammer prüfte die anderen Argumente der Parteien und kam zu dem Schluss, dass die strittigen Merkmale in einem breiteren Sinne von der Fachperson verstanden werden, als die Beschwerdegegnerin argumentiert hatte. Da sämtliche Merkmale des Anspruchs 1 des Hauptantrags in D3 offenbart worden waren, entschied die Kammer, dass sein Gegenstand nicht neu war.

In T 325/23 the board agreed with the appellant (patent proprietor) that in general there exists no file wrapper estoppel in proceedings under the EPC. A file wrapper estoppel is a concept in US patent law. It refers to the doctrine that the patent proprietor may be estopped from enforcing an interpretation of patent claims that is inconsistent with statements made during the patent prosecution process. This concept does not exist in the EPC. However, the fact that the appellant had argued during the prosecution of the patent application that the limitation "single row" added to claim 1 was made in order to limit the subject-matter of claim 1 against prior-art document D9 which disclosed "multiple rows", could be taken as an indication that a narrow interpretation of the term "single row" was at least not technically unreasonable. It was therefore appropriate, at a later stage of the proceedings, to follow such a narrow interpretation, which had even been adopted by the appellant during earlier proceedings. Such an interpretation did not correspond to a "file wrapper estoppel" because it did not limit the interpretation of a certain feature to what was argued by the then applicant for all future proceedings. Rather, the consideration of such events in the file history was used to determine whether an interpretation was technically reasonable or not, without excluding other interpretations.

The board did not agree with the appellant's assumption that once an interpretation of a feature was determined, it could only be assessed whether this interpretation contravened Art. 100(c) EPC. Other interpretations were, according to the appellant, no longer relevant for the assessment of the admissibility of amendments.

According to settled case law of the Boards of Appeal, all technically reasonable interpretations of an ambiguous claim have to be considered. If one of those interpretations contains matter that extends beyond the content of the application as originally filed, it has to be concluded that there is added subject-matter (CLB, 10th edn. 2022, II.E.1.3.9e)).

In the context of claim interpretation the appellant further argued that a non-specific definition in a claim should be given its broadest technically sensible meaning and referred inter alia to the chapters II.A.6.1 and I.C.4.1 of CLB, 10th edn. 2022. The board disagreed. While it is true that according to these two chapters a non-specific definition in a claim should be given its broadest technically sensible meaning, none of these citations refer to the interpretation of claims in the context of assessing the admissibility of amendments under Art. 100(c) EPC or Art. 123(2) EPC. The board therefore concluded that all technically reasonable interpretations of the disputed feature had to be taken into account for the assessment under Art. 100(c) EPC.

In the case in hand, the disputed feature was feature (h). The board assessed whether the (narrow) interpretation of feature (h), according to which "single row" meant a single connector line, was already encompassed by the content of the application as filed and it concluded that the ground for opposition pursuant to Art. 100(c) EPC prejudiced the maintenance of the patent as granted (main request). The same reasons applied to auxiliary requests IA and IB and I to XXIII.

In T 583/23 the parties agreed that claim 1 related to a closed composition, i.e. a smoke condensate that did not include other components than those stated in the claim.

The board noted that claim construction, namely the meaning that a skilled person would give to the wording of a claim, was a question of law. In determining this, the board was not bound by the parties' views on the matter. The smoke condensate composition defined in claim 1 was introduced by the term "comprising." Due to the open-ended nature of this formulation, the inclusion of additional ingredients was, in principle, not excluded. Moreover, the scope of claim 1 included smoke condensates having a low pH of between 2.0 and 3.5, which were a preferred embodiment in the patent. These smoke condensates must necessarily comprise acids. Likewise, claims 2 and 3 contained further limitations which were not in line with a "closed" interpretation of claim 1.

Citing T 107/14 and T 303/20, the respondent (opponent) had argued that claim 2 as granted was a "false dependent claim" because it altered the closed composition of an allegedly closed independent claim 1. The board disagreed. As suggested in T 107/14, whether a particular amendment extended beyond the content of the application as originally filed must be assessed based on the information that is clearly and unambiguously disclosed in the entire application as originally filed, i.e. on the merits of the specific case. The same holds true for the interpretation of a specific claim and the question of whether it is a dependent claim or not.

According to the board, the indication "and the rest water" in claim 1 did not rule out the presence of further components in the smoke condensates, as long as water complemented the composition to 100 wt%. Such an interpretation of claim 1 was technically not nonsensical. By contrast, it was in line with e.g. claims 2 and 3 when interpreted as "truly dependent claims", and it led to a scenario which was not at variance with the teaching of the patent itself.

For these reasons, the board construed claim 1 as encompassing smoke condensates which could comprise other components than those explicitly specified in the claim ("open claim formulation"), such as, undoubtedly, acids.