Defending an inventive step even when the formulated objective problem contains elements of the solution
Case Law | 05.03.2026
In 3 Ni 20/23, litigated by Peter Klusmann, Jan Carl Zillies and Dirk Schüßler-Langeheine, HOFFMANN EITLE successfully defended a patent against an inventive step objection before the German Federal Patent Court (FPC).
The patent, titled “DIARYLHYDANTOIN COMPOUND”, related to prostate cancer treatments. The FPC referred to the problem mentioned in the patent, which identifies a need for a new thiohydantoin compound in such treatments, and consequently formulated the problem as the provision of new compounds having the basic thiohydantoin structure. Notably, the problem was phrased in a way that contained an element of the claimed solution. However, according to the FPC, the patent itself defined the problem in such a way and was hence confined to a thiohydantoin compound. A broader formulation of the problem, which is free of any elements of the solution, would thus not have been justified.
Despite the narrower formulation of the problem, HOFFMANN EITLE could defend the “DIARYLHYDANTOIN COMPOUND” patent. The defence nicely illustrates the German inventive step practice, where the technical problem is less relevant than motivations provided by the prior art, which prompt the skilled person to work in a specific area. In the present case, the skilled person would have had to make specific structural modifications to known compounds in order to reach into the scope of the claims. Hoffmann Eitle successfully argued that there was no sufficiently specific motivation to make such changes. In essence, too many modifications were possible and most were associated with a risk of ending up with a worse performing compound. Thus, the skilled person would have had to resort to inventive skill to end up with the claimed compound.
Thus, even when a German court or office formulates a relatively narrow problem, this does not necessarily have an impact on the inventive step position. Only if it can be shown that the skilled person was motivated by the prior art to work in the claimed area, can an inventive step be denied.
In the meantime, the decision has become res judicata.