In T 363/90 a machine fitted with a sheet feeder corresponding to the claimed invention had been exhibited and demonstrated at trade fairs. The board concluded that, under the circumstances, it was impossible for the skilled person to recognise – or to infer on the basis of further information – the technical features and the functions of the exhibited sheet feeder to an extent which would have enabled him to copy its design, let alone develop it further.

In T 208/88 date: 1990-02-28 (OJ 1992, 22) the board held that an effect (in this case, growth regulation) not previously described, but actually occurring during the execution of a known teaching (in this case, use as a fungicide) and intended as the basis of a use invention, had in any event not been made available to the public, if it was not revealed so clearly during such execution as to disclose the invention's essential character, at least potentially, to an unlimited number of skilled persons (cf. G 6/88).

In T 245/88 several vaporisers had been installed in a fenced-off area of a shipyard. The public did not have unrestricted access to this area. The board was of the view that the vaporisers had not been made available to the public.

In T 901/95 the board decided that merely claiming that generating equipment was installed into ships at three different shipyards and thus available to the public was not enough to demonstrate its obvious prior use. Shipyards were normally considered restricted areas and thus not open to the general public. Nor could the possibility be excluded that shipyards' business partners might secure their common interests through explicit or tacit secrecy agreements, in the absence of other protection. In the case in point, it was also questionable whether the relevant process steps and the functional arrangement of the switching means were apparent from merely looking at built-in apparatus; nor was it certain when the generating installations had become operational. The board did not in these circumstances consider the alleged public prior use.

In T 801/98 the board, having found that an alleged prior use by sale, in the form of a delivery of locks to a psychiatric clinic before the contested patent's priority date, had been established, considered that there was insufficient evidence to overcome the doubts as to whether it had been public.

In T 945/09 (patient – clinical trials) the board found that there had been prior use but it had not been public.

In T 1410/14 it was common ground between the parties that a vehicle ("City Runner") with the claimed features had been test driven on a route forming part of a town's public transport network on a particular date, but also that the coupling joint in question could have been seen only from above, namely from an overhead pedestrian bridge. For the board, it was not proven that this prior use would have enabled a skilled person to identify all the features of the invention. In particular, the appellant had failed adequately to show that a specific feature (a bracket forming part of the pivot bearing and held displaceably on the coach body) had been apparent to the skilled person during the test drives. Summing up, the board held that features of subject-matter that had been visible only briefly could be considered to have been made publicly available only if it could be shown beyond doubt that they had been clearly and directly apparent to the skilled person for that short time. In T 1551/14, the patentee relied on T 363/90 and T 1410/14. The board considered that these decisions did not apply to the case in hand

In T 1217/01 an invoice was the only document bearing a date earlier than the contested patent's priority date that had been adduced by the appellant (opponent) in support of an alleged prior use, but it did not disclose the composition of the product sold. The board found that the product's composition could therefore be deduced only by "reverse reasoning", working back from the invoice to the product's production (packaging, mixture, weight, elaboration) and, from there, to the formula used. However, owing especially to changes in product names and numbering, which made it impossible to reconstruct where the cited product fitted into the product family, the board ultimately ruled that the evidence was not conclusive enough.

In case T 1534/16 the appellant (patent proprietor) raised doubts concerning the public availability of the installations in accordance with the alleged prior uses, in particular by referring to the presence of an obligation to maintain secrecy. The board, regarding the appellant's doubts as justified and considering that further investigations would require the co-operation of the opponent, who withdrew its opposition, concluded that the allegations of prior use were to be disregarded.