10.2.3 Development of the art in a different direction

One form of secondary indicia in the nature of a "technical prejudice" is a development of the art in a different direction (T 24/81, OJ 1983, 133; T 650/90; T 330/92).

In T 883/03 the board found that the teaching that could have led to the characterising feature of claim 1 had long formed part of the state of the art; yet for all that time experts had been "blind" to that knowledge. In the case in point that was a further indication of the inventiveness of the solution proposed in claim 1.

In T 872/98 the board pointed out that the presence of secondary indicia might also be attested by the fact that a competitor had, shortly after the priority date, filed a patent application with the German Patent Office in which the invention took an entirely different direction to the European application.

In T 779/02 the board indicated that a prejudice could be proved by the fact that the closest prior art and the invention were separated by a long period of time (over 16 years in the case in hand), during which time the only solutions pursued led away from the invention, and the solution provided by the invention only becoming acceptable to experts in the field after this time.