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 (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 84/83 a new type of wide-angle mirror had been fitted to a motor vehicle for demonstration purposes for at least six months. The board held this to constitute prior public use as, during such a time, the vehicle could be expected to be parked on public highways and hence open to inspection by third parties.
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.