It is legitimate to have a mix of technical and non-technical features appearing in a claim, as is often the case with computer-implemented inventions. The non-technical features may even form a major part of the claimed subject-matter. However, in the light of Art. 52(1), (2) and (3), the presence of an inventive step under Art. 56 requires a non-obvious technical solution to a technical problem (T 641/00, T 1784/06).
When assessing the inventive step of such a mixed-type invention, all those features which contribute to the technical character of the invention are taken into account. These also include the features which, when taken in isolation, are non-technical, but do, in the context of the invention, contribute to producing a technical effect serving a technical purpose, thereby contributing to the technical character of the invention. However, features which do not contribute to the technical character of the invention cannot support the presence of an inventive step (T 641/00). Such a situation may arise, for instance, if a feature contributes only to the solution of a non-technical problem, e.g. a problem in a field excluded from patentability (see G‑II, 3 and sub-sections).
The problem-solution approach is applied to mixed-type inventions in such a way as to ensure that inventive step is not acknowledged on the basis of features not contributing to the technical character of the invention, while all those features which do contribute are properly identified and taken into account in the assessment. To this end, where the claim refers to an aim to be achieved in a non-technical field, this aim may legitimately appear in the formulation of the objective technical problem as part of the framework of the technical problem that is to be solved, in particular as a constraint that has to be met (T 641/00; see step (iii)(c) below and G‑VII, 5.4.1).
The steps below outline the application of the problem-solution approach to mixed-type inventions:
Determination of the features contributing to the technical character of the invention should be performed for all claim features in step (i) (T 172/03, T 154/04). However, in practice, due to the complexity of this task, the examiner can normally perform the determination in step (i) on a first-glance basis only and perform the analysis at the beginning of step (iii) in a more detailed manner. In step (iii), the technical effects achieved by the differences over the selected closest prior art are determined. The extent to which the differences contribute to the technical character of the invention is analysed in relation to these technical effects. This analysis, limited to the differences, can be performed in a more detailed manner and on a more concrete basis than the one performed at step (i). It may therefore reveal that some features considered in step (i) at first glance as not contributing to the technical character of the invention do, on closer inspection, make such a contribution. The reverse situation is also possible. In such cases, the selection of the closest prior art in step (ii) might need to be revised.
When performing the analysis in steps (i) and (iii) above, care should must be taken to avoid missing any features that might contribute to the technical character of the claimed subject-matter, in particular if the examiner reproduces his understanding of the subject-matter of the claim in his own words during the analysis (T 756/06).