T 0741/91 (BON-3-acid/Ueno) vom 22.09.1993

inventive step (yes)
problem and solution
comparative test - not expertly worked
feature disclosed in old document disregarded among experts
late submitted material - evidence admitted (no)

1. A proper application of the so-called "problem-solution- approach" requires the avoidance of formulating artificial and unrealistic technical problems (following T 0495/91; No. 3.3 of the Reasons).
2. All embodiments falling within a process claim have to meet the requirements of patentability set out in Articles 52 to 57 EPC (No. 4.2 of the Reasons).
3. To be relevant, it is sufficient for experiments, which aim at establishing that the promised result cannot be obtained over the whole range of a claim that they are carried out according to the Claim and with the normal experience of the man skilled in the art (Nos.4.2 and 4.3 of the Reasons).
4. An experiment which was not expertly carried out is not credible and sufficient evidence that a claim comprises embodiments which do not solve the technical problem (No. 4.5 of the Reasons).