Abstract on Article 087(1) EPC for the decision T0378/24 of 12.03.2026

T 378/24 was an appeal against the examining division's decision to refuse the European patent application on the grounds that the subject-matter of claims 1, 3, 4, 5, 9, 14, 15 and 16 of the main request lacked novelty over document D5, which was prior art pursuant to Art. 54(3) EPC. The patent related to a method and system for pre-purification of a feed gas stream. The board noted that, in accordance with G 1/15, the decisive issue was whether the subject-matter encompassed by the claims of the main request and corresponding to the novelty-destroying disclosure of D5 was entitled to the claimed priority date. In this regard, the board disagreed with the interpretation of G 1/15 set out in the decision under appeal. The board clarified that, for entitlement to partial priority pursuant to Art. 88(3) EPC, G 1/15 did not require a claim to spell out alternatives comprised within the claim as such, or to comprise the conjunction "or" separating alternatives therein. The referral leading to G 1/15 was prompted by divergent interpretations of Opinion G 2/98, in particular of the passage in point 6.7 of the Reasons according to which: "the use of a generic term or formula in a claim for which multiple priorities are claimed in accordance with Article 88(2) EPC, second sentence, is perfectly acceptable under Articles 87(1) and 88(3) EPC, provided that it gives rise to the claiming of a limited number of clearly defined alternative subject-matters". Certain decisions issued after G 2/98 construed this latter requirement ("provided that...") restrictively and denied partial priority where such alternatives were not explicitly defined. This approach was expressly rejected in G 1/15. The board referred to the Order of G 1/15 which explicitly states that no such limitations or conditions apply in this respect. It pointed out that further guidance was provided in point 6.4 of the Reasons: "In assessing whether a subject-matter within a generic "OR" claim may enjoy partial priority, the first step is to determine the subject-matter disclosed in the priority document that is relevant, i.e. relevant in respect of prior art disclosed in the priority interval ... The next step is to examine whether this subject-matter is encompassed by the claim of the application or patent claiming said priority. If the answer is yes, the claim is de facto conceptually divided into two parts, the first corresponding to the invention disclosed directly and unambiguously in the priority document, the second being the remaining part of the subsequent generic "OR"-claim not enjoying this priority but itself giving rise to a right to priority, as laid down in Article 88(3) EPC." The board stated that, according to G 1/15, it was not necessary for alternatives within a claim to be individually spelt out or syntactically separated by "or"; it suffices that the claim can be conceptually or mentally divided into different subject-matters. Applying the principles set out in G 1/15 to the case in hand, the board found that independent claims 1 and 14 of the main request could be conceptually divided into two sets of alternative subject-matters, namely: (1) a first set corresponding to conceptual alternatives encompassed by the claim which were directly and unambiguously disclosed in the priority document and (2) a second set corresponding to the remaining alternatives encompassed by the claim but not directly and unambiguously disclosed in the priority document. The first set of alternatives was entitled to the claimed priority date, while the second set of alternatives was not. It followed that partial priority could be acknowledged for the subject-matter of independent claims 1 and 14 insofar as this subject-matter was conceptually encompassed by the claims and directly and unambiguously disclosed in the priority document. Hence, in the present case, for D5 to be relevant state of the art pursuant to Art. 54(3) EPC, the novelty-destroying subject-matter disclosed in D5 had to fall into the second set of alternatives conceptually falling within the scope of independent claims 1 and 14 of the main request as set out above, namely those alternatives not entitled to the priority date. The board analysed the disclosure in D5 and found that claims 1 and 14 of the main request were entitled to the priority date of the present application, such that D5 was not state of the art pursuant to Art. 54(3) EPC for these alternatives. The board concluded that the subject-matter of independent claims 1 and 14, and by extension dependent claims 2 to 13, 15 and 16, were novel over D5. The decision under appeal was set aside and the case was remitted to the examining division for further prosecution.