According to the case law of the boards of appeal, alleged advantages to which the patent proprietor/ applicant merely refers, without offering sufficient evidence to support the comparison with the closest prior art, cannot be taken into consideration in determining the problem underlying the invention and therefore in assessing inventive step (see T 20/81, OJ 1982, 217; T 181/82, OJ 1984, 401; T 124/84, T 152/93, T 912/94, T 284/96, T 325/97, T 1051/97). In T 1027/08, the board added that there was no reason to deviate from this case law as it was based on the understandable rule that a patent can only properly be granted for a solution claimed as non-obvious if it actually has the alleged effect (see also point 4.6. below).
Some beneficial effects or advantageous properties, if appropriately demonstrated by means of truly comparable results, can in certain circumstances properly form a basis for the definition of the problem that the claimed invention sets out to solve and can, in principle, be regarded as an indication of inventive step. The only comparative tests suitable for this are, however, those which are concerned with the structurally closest state of the art to the invention, because it is only here that the factor of unexpectedness is to be sought (T 181/82, OJ 1984, 401; T 998/04, T 955/96, T 234/04, T 378/03, T 1761/07; see also point 10.9 below).
In T 355/97 the patent related to an improved hydrogenation process for preparing 4aminophenol. The technical problem as indicated in the patent in suit consisted of improving the performance index of the preparation process without loss of selectivity. The patent proprietor, however, did not demonstrate properly that the purported advantages, i.e. improvement of the performance index without loss of selectivity, of the claimed invention had successfully been achieved. The board referred to the above mentioned jurisprudence and held that, since the alleged advantages lacked the required adequate support, the technical problem needed reformulation. Therefore, the objective problem could only be seen as merely providing a further method for preparing 4aminophenol (see also T 1213/03). If the proprietor of the patent alleges the fact that the claimed invention improves a technical effect, then the burden of proof for that fact rests upon him (see also T 1213/03, T 1097/09, T 2418/10).