Problem and Solution Approach
The "problem and solution" approach is often used by the European Patent Office for evaluating the inventive step of an invention and contains three steps:
- Determining the closest prior art
- Establishing the technical problem to be solved, and
- Considering whether or not the claimed invention, starting from the closest prior art and the technical problem, would have been obvious to the skilled person.
The closest prior art is the combination of features derivable from a single reference that provides the best basis for evaluating an inventive step. The closest prior art may be, for example, i) a known combination in the technical field concerned that discloses technical effects, purpose or intended use, that are most similar to that of the claimed invention or ii) the combination having the greatest number of technical features in common with the features of the invention and being capable of achieving the effects of the invention.
The second step must establish the technical problem to be solved in an objective way. For this purpose, the patent application, the closest prior art, and the differences in terms of either structural or functional technical features between the invention and the closest prior art are determined and used in the formulation of the technical problem. The technical problem is concerned with modifying the closest prior art to achieve the technical effects associated with the invention.