T 1091/23 (UE capability transmission/HUAWEI) 22-07-2025

1. The present application concerns the sending of terminal capability information by a terminal to a base station. The capability information relates to the channel state information (CSI) reporting capability of the terminal and may correspond to a particular codebook.

2. Main request

The claim set of the main request was filed for the first time with the statement of grounds of appeal.

2.1 Interlocutory revision (Article 109(1) EPC)

2.1.1 The appellant asked in its statement of grounds of appeal that the examining division "rectify its decision of the oral proceedings according to Article 109(1) EPC". Moreover, the new main request corresponded "mainly to the suggestions in section 4 of the summons to attend oral proceedings dated March 22, 2022/respectively the suggestions in section 4 of the communication of the examining division dated August 12, 2021".

2.1.2 In that regard, the board recalls that Article 109(1) EPC stipulates that, if the department whose decision is contested considers the appeal to be admissible and well founded, it shall rectify its decision. The main purpose of this provision is to shorten the appeal proceedings to the benefit of procedural expediency and economy and to avoid unnecessary workload for the Boards of Appeal in the interest of both the appellant and the EPO (see e.g. T 1060/13, Reasons 4.1). According to the established case law, interlocutory revision must be granted if the amendments clearly overcome the grounds for refusal, even if further objections arise and even if previous objections or statements were indicated by the first-instance department (see e.g. T 1060/13, Reasons 4.3; T 682/22, Reasons 2.4.1).

2.1.3 In the present case, despite the fact that the board may only speculate as to the actual reasons on the basis of which interlocutory revision of the appealed decision was not granted by the examining division since the latter is bound to silence as to its grounds pursuant to Article 109 (2) EPC ("without comment as to its merit"), the respective statements set out in the above-referenced previous communications of the examining division do not appear to be sufficient to justify that the sole ground for refusal (i.e. lack of novelty here) is indeed clearly overcome now by the amendments made to claim 1 of the new main request.

2.1.4 In view of the above, the board fails to see why the examining division should have granted interlocutory revision in this case.

2.2 Admittance of the main request (Article 12 RPBA)

2.2.1 Claim 1 of the main request includes added features (c) and (d) and was filed for the first time with the statement of grounds of appeal. Its admittance is therefore at the board's discretion under all relevant parts of Article 12 RPBA.

2.2.2 According to the appellant's own argumentation, the main request constitutes a reaction to statements provided in the examining division's annex to the summons to oral proceedings and in preceding communications (see point 2.1.1 above).

2.2.3 By submitting this claim request only after the examining division has refused the present application, the appellant effectively prevented that a reasoned decision on such a request could have been taken by the examining division. However, this runs counter to the main aim of reviewing decisions of the first-instance departments in appeal proceedings (cf. Article 12(2) RPBA). Thus, the appellant should indeed have filed this claim request already during the examination proceedings within the meaning of Article 12(6), second sentence, RPBA; for instance, in direct response to the above-referenced communications. However, for whatever reasons, the appellant did not do so.

2.2.4 Furthermore, admitting the new main request, including new features (c) and (d), would now either lead to an increased complexity (due to a fresh assessment of novelty and even inventive step, added subject-matter, clarity, etc.) or to a remittal which would in turn be contrary to procedural economy (see the criteria mentioned in Article 12(4), fifth sentence, RPBA).

2.2.5 The board is not convinced by the appellant's argument that the main request could not have been filed earlier, since the examining division "never gave a firm, positive indication that the combination of (i) a per-slot CSI-RS-port limit and (ii) two pieces of capability information would truly overcome its objections". This is because the examining division is not obliged to provide any indication as to how its objections may be overcome and thus such an indication cannot serve as a justification for belatedly filing further requests.

2.2.6 In view of the above, the board decides not to admit the main request into the appeal proceedings (cf. Article 12(4) and (6) RPBA).

3. Auxiliary requests 1 and 2

Claim 1 of both auxiliary requests 1 and 2 are identical.

3.1 Novelty (Article 54 EPC)

3.1.1 It is common ground that document D1* discloses, in paragraph [0709], the transmission of "the total number (M) of CSI-RS resources" together with "the total number of CSI-RS ports which are maximally supported [...] for each CSI-RS resource", i.e. the UE is indicating the total number of CSI-RS ports maximally supported by the UE. Thus, the issue under dispute is the question whether the indication in document D1* is also relative to "each slot of time domain", as in feature (b).

3.1.2 The board is not convinced by the appellant's argument that document D1* does not disclose the claimed maximum number of supported CSI-RS ports per time slot, since the total number MxK of supported "CSI-RS ports" indicated in document D1* could well span more than one slot.

3.1.3 Rather, the board holds that the correspondence of ports and slots is evident e.g. from Fig. 25 of D1*. There, it is shown that the "8-port CSI-RS pattern 0" is contained entirely within the first slot, whereas "8-port CSI-RS pattern 1" is contained entirely within the second slot, i.e. all 8 ports are used within each time slot.

3.1.4 Moreover, the board does not subscribe to the appellant's view that the claimed number of ports per slot was more granular than what is disclosed in document D1*. According to document D1*, the number of ports is provided per CSI-RS resource. However, as evident from Fig. 25 of D1*, a CSI-RS resource fits within a slot (i.e., in Fig. 25, each of the patterns is contained within a particular slot) and is thus more granular, contrary to the appellant's contention.

3.1.5 Moreover, document D1* discloses, in paragraph [0725], that "the base station determines a CSI-RS configuration to be transmitted to the UE based on the received UE capability signaling". This in turn corresponds to the objective technical problem of "enabl[ing] the network to configure CSI-RS resources that fully utilise (...) the UE's processing capacity within each slot" submitted by the appellant (see its letter of reply dated 1 July 2025, page 10, third full paragraph). In consequence, the allocation of CSI-RS patterns by the base station shown in Fig. 25 of D1* in fact mirrors what has been communicated by the UE.

3.1.6 Lastly, the board notes that the cited passages of document D1* do not describe how the network actually configures the CSI-RS resources, but neither does present claim 1. Therefore, it even could not be deduced from the claim wording that the alleged objective technical problem was solved by the claimed invention in a different way.

3.1.7 Therefore, the subject-matter of claim 1 is not novel over the disclosure of document D1*.

3.2 In view of the above, the board concurs with the examining division that auxiliary requests 1 and 2 are not allowable under Article 54 EPC.

4. Auxiliary request 3

4.1 Added subject-matter (Article 123(2) EPC)

4.1.1 Claim 1 of auxiliary request 3 defines, in feature (b), properties of "the capability information". In subsequent feature (c), however, a "first" and a "second" capability information are introduced. This can reasonably be interpreted such that the property of "the capability information" defined in feature (b) is not a property of the "first" or the "second" capability information, but the property of another, unspecified piece of information comprised within "the capability information".

4.1.2 The board does not subscribe to the appellant's argument that this was supported by the original disclosure which - according to the appellant - "establishes the concept of multiple, type-specific capability vectors". Rather, the board holds that the wording of claim 1 is such that it comprises the interpretation provided in point 4.1.1 above, which goes beyond such a concept and thus extends beyond the content of the application as originally filed.

4.2 Thus, auxiliary request 3 is not allowable under Article 123(2) EPC.

5. Auxiliary requests 4 to 6

5.1 Admittance (Article 13(2) RPBA)

5.1.1 Auxiliary requests 4 to 6 were filed after the notification of the board's communication under Article 15(1) RPBA. Admittance of those claim requests are thus governed by Article 13(2) RPBA.

5.1.2 As to the content of the late-filed claim requests, the claims of auxiliary request 4 are based on those of the main request and differ in that the wording has been amended to comply with Article 123(2) EPC. Moreover, claim 1 of this request recites an explicit step of "generating", which incorporates aspects previously scattered across the different features of claim 1 of the main request, and includes a "receiving" step.

Claim 1 of auxiliary request 5 differs from claim 1 of auxiliary request 4 in that it omits the "generating" and the "receiving" steps (which are however already known from document D1*).

Unlike auxiliary requests 4 and 5, which are based on the (non-admitted) main request, auxiliary request 6 is based on auxiliary request 3 (considered in the decision under appeal as "auxiliary request 2").

5.1.3 The board notes upfront that the fact that the board has formulated in its communication under Article 15(1) RPBA objections against the main request does not give the appellant a "carte blanche" for filing new auxiliary requests overcoming these objections. Rather, the board formulated these objections in order to provide guidance to the appellant in case the appellant managed to convince the board, during the arranged oral proceedings, to eventually admit the main request into the appeal proceedings (see T 2271/18, Reasons 3.3; T 2632/18, Reasons 4.3).

5.1.4 More specifically, as to auxiliary requests 4 and 5, these claim requests constitute a belated - albeit indirect - response to the examining division's negative opinion expressed already in its annex to the summons to oral proceedings dated 22 March 2022. Furthermore, as to the merits of auxiliary request 6, the board additionally notes in a prima facie manner that the passages of document D1* cited by the examining division (notably paragraph [0747]) disclose transmitting information about a UE's codebook capabilities, albeit not explicitly in combination with the "information on the total number (K) of CSI-RS ports maximally supported for each CSI-RS resource" indicated in paragraph [0709] of document D1*. Nevertheless, the board understands that the latter is "corresponding to" the current "codebook" employed by the base station. This applies to the currently used "BWP size" analogously. Accordingly, the "sending" of "the first capability information" aspect of claim 1 is already known from document D1* (see point 3.1 above). Thus, the subject-matter of present claim 1 appears to differ from the disclosure of document D1* only in that the latter discloses sending a single capability information, while claim 1 mandates two distinct capability information items, corresponding to a different "codebook type" and different "BWP size". However, such a difference cannot be inventive, since it evidently constitutes a routine measure for the skilled person to decide at which point in time parameters are calculated and transmitted for providing beforehand the "quantity of ports" applicable to a different CSI measurement.

5.1.5 Hence, the board cannot see any "cogent reasons" justifying "exceptional circumstances" within the meaning of Article 13(2) RPBA.

5.2 As a consequence, the board decides not to admit auxiliary requests 4 to 6 into the appeal proceedings (Article 13(2) RPBA).