The "problem and solution approach" is regularly applied by the departments of the EPO in the course of deciding whether or not claimed subject-matter fulfils the requirements of Art. 56 EPC. This consists essentially of (see also Guidelines G-VII, 5 - June 2012 version):
(i) determining the "closest prior art",
(ii) establishing the "objective technical problem" to be solved, and
(iii) considering whether or not the claimed invention, starting from the closest prior art and the objective technical problem, would have been obvious to the skilled person.
On application of the problem and solution approach to claims comprising technical and non-technical aspects (especially in the case of computer-implemented inventions), see point 9.1 below, and for its application to claims directed to chemical inventions, see point 9.8.1.
The boards frequently cite R. 27(1)(c) EPC 1973 (new R. 42(1)(c) EPC) as the basis for the problem and solution approach. R. 42(1)(c) EPC requires that the invention be disclosed in such terms that the technical problem (even if not expressly stated as such) and its solution can be understood. Problem and solution are thus component parts of any technical invention. The problem and solution approach was primarily developed to ensure objective assessment of inventive step and avoid ex post facto analysis of the prior art.
According to board of appeal case law (see T 1/80, OJ 1981, 206; T 20/81, OJ 1982, 217; T 24/81, OJ 1983, 133; T 248/85, OJ 1986, 261), the assessment of inventive step has to be based on the objective, not subjective, achievement of the inventor. By starting out from the objectively prevailing state of the art, the technical problem is to be determined on the basis of objective criteria and consideration given to whether or not the disclosed solution is obvious to the skilled person. Although the problem and solution approach is not mandatory, its correct application facilitates the objective assessment of inventive step. The correct use of the problem and solution approach rules out an ex post facto analysis which inadmissibly makes use of knowledge of the invention (T 564/89, T 645/92, T 795/93, T 730/96 and T 631/00). In principle, therefore, the problem and solution approach is to be used; however, if exceptionally some other method is adopted, the reasons for departing from this generally approved approach should be stated.
In T 967/97 the board stated that the problem and solution approach was essentially based on actual knowledge of technical problems and ways to solve them technically that the skilled person would, at the priority date, be expected to possess objectively, i.e. without being aware of the patent application and the invention that it concerned. If the skilled person had a choice of several workable solutions that might suggest the invention, the rationale of the problem and solution approach required that the invention be assessed relative to all these possible solutions before any decision confirming inventive step was taken. To deny inventive step, no special grounds had to be given for a pre-selection of prior-art citations, even if several workable solutions were available to the skilled person; the statement of grounds merely served to show that the invention was obvious to the skilled person from the prior art in relation to (at least) one of these solutions (see also T 558/00, T 970/00, T 172/03, T 323/03, T 21/08, T 308/09, T 1289/09).
In T 188/09 the board noted first that whatever approach was applied as an auxiliary means for the evaluation of inventive step of claimed subject-matter, in a given evidential situation it had to provide the same result, be it either in favour of or against inventive step. Therefore, even if the "problem and solution approach" was applied, the decision on inventiveness should be the same as if it had not been used. Citing T 465/92 (OJ 1996, 32), the board observed: "if an invention breaks new ground it may suffice to say that there is no close prior art rather than constructing a problem based on what is tenuously regarded as the closest prior art."
In T 465/92 (OJ 1996, 32) the board did not take the problem and solution approach when assessing inventive step, and said this was merely one possible approach, with advantages and drawbacks. It took the view that all of the seven relevant citations came equally close to the invention.