Abstract on Article 056 EPC for the decision T1719/21 of 16.10.2025

In T 1719/21 there was a focus on the extent to which commercial, non-reproducible products – particularly ENGAGE® 8400 – could belong to the closest prior art in the light of G 1/23 for the purposes of inventive step. An object of the present invention was to provide an encapsulating material for a solar cell having excellent insulating properties. D11 was concerned with the same objective. Responding to an argument by the respondent submitted before issuance of G 1/23 that the example of D11 using a commercial polymer did not represent an enabling disclosure, as information on the physical properties of that polymer was missing and its synthesis was not described, the board noted the Enlarged Board in G 1/23 had rejected an interpretation of G 1/92 according to which a non-reproducible but otherwise existing and commercially available product would not belong to the state of the art. The respondent’s view that it would be unrealistic and necessarily contaminated by hindsight to assume that a skilled person would start from a non-reproducible polymer was thus as a principle not accepted by the board. The exemplified encapsulating material described in D11 belonged to the state of the art and represented a suitable starting point for the skilled person aiming at providing an encapsulating material for a solar cell having excellent insulating properties. The appellant objected in addition that the subject-matter of claim 1 of Auxiliary Request 2 lacked an inventive step over the disclosure of D4 (ENGAGE® 8400) taken as the closest prior art. As with D11, the respondent had contested before the issuance of G 1/23 that the commercial product ENGAGE® 8400 was not enabled and thus should not be considered to have been made available to the public within the meaning of Art. 54(2) EPC. In view of decision G 1/23, however, the board found that ENGAGE® 8400 and all its analysable properties and structure did belong to the state of the art. The product was physically accessible, irrespective of whether or not particular reasons could be identified for analysing its composition and structure, also if the skilled person would not have been in the position to reproduce it on their own (see G 1/23, point 91 of the Reasons). The respondent submitted that the Enlarged Board in G 1/23 had expressed serious concerns whether a product such as ENGAGE® 8400 could represent the closest prior art, despite the fact that this product and its analysable properties belonged to the state of the art within the meaning of Art. 54(2) EPC. It cited in particular point 47 of the Reasons: "When applying the problem-solution approach, it may well be a plausible argument that the skilled person faced with the objective technical problem of manufacturing a product with similar properties cannot be assumed to depart from the product ENGAGE 8400 because its method of manufacture is not in the public domain. It can be argued that a skilled person would turn to some other starting point, purely as a question of identifying the theoretical "closest prior art". The board did not agree with the respondent’s interpretation of G 1/23. Reasons 45 to 48 of G 1/23 were concerned with the reproducibility requirement establishing a legal fiction and the analysis therein lead the Enlarged Board to the conclusion that the fiction of the exclusion of a product from the state of the art in view of the reproducibility requirement should be treated with serious reservations. The scope of the sections of G 1/23 relied upon by the respondent was to show that the assumption that a commercially available product was legally non-existing was artificial and manifestly contradicting notorious facts. The Enlarged Board expressly rejected the position that a non-reproducible, but otherwise existing and commercially available product, does not belong to the state of the art, as this interpretation leads to an absurd result and therefore cannot hold. ENGAGE® 8400 was taken as an example of a commercial product for the purpose of the reasoning. This, the board in the case in hand stated, was accidental due to the fact that ENGAGE® 8400 was also the product considered in the referring decision (T 438/19 of 27 June 2023). Moreover, the board did not agree that a non-reproducible, but commercially available, product or a product difficult to reproduce could not constitute a promising starting point for evaluating the existence of an inventive step. When selecting a promising starting point for an invention, the skilled person will take into account relevant technical information on products put on the market. The Enlarged Board ruled that such technical information made available to the public before the filing date forms part of the state of the art within the meaning of Art. 54(2) EPC irrespective of whether the skilled person could analyse and reproduce the product and its composition or internal structure before that date (G 1/23, Headnote II). What needs to be modified, however, is part of the inventive thinking of the skilled person in order to solve the problem addressed, not a consideration concerning the selection of that starting point.