T 0024/81 - The problem-solution-approach - #66

Citation rank: 66
No. of citations: 73

T 24/81 is one of the landmark decisions, on which the problem-solution-approach for the assessment of inventive step is based.

The problem-solution-approach was developed by the Boards of Appeals to make the assessment of inventive step as objective as possible. For example, the approach is based on an "objective technical problem", which results from the technical effect that the distinguishing features add to the closest prior art.

According to the current Guidelines (2017, G-VII, 5), the problem-and-solution approach, includes three main stages:

(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.

Correct application of the problem and solution approach avoids this inadmissible ex post facto analysis which draws on knowledge of the invention (T 24/81).

The EPO's Case Law Book, at least for inventions in the chemical field (I.D.9.8.1), mentions further steps in the problem-solution-approach. The steps to be followed according to the CLB are:

a) establishing the closest prior art
b) defining the problem in the light of that prior art
c) identifying the solution
d) demonstrating the success of the solution
e) optionally reformulating the problem
f) examining the obviousness of the solution in view of the state of the art

In the additional step d) it is verified that the distinguishing features indeed solve the objective technical problem, and if not, the problem is re-formulated in step e), often in a less ambitious manner, e.g., as providing a mere "alternative" to what is described in the closest prior art.

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Headnotes:

I. Objectivity in the assessment of inventive step is achieved by starting out from the objectively ruling state of the art, in the light of which the technical problem is determined which the invention addresses and solves from an objective point of view, and consideration is given to the question of the obviousness of the disclosed solution to this problem as seen by the man skilled in the art and having those capabilities which can be objectively expected of him. In contrast a mere investigation for indications of the presence of inventive step is no substitute for the technically skilled assessment of the invention vis-a-vis the state of the art, pursuant to Article 56 EPC. Where such indications are present, the overall picture of the state of the art and consideration of all significant factors may show that inventive step is involved, but will not necessarily do so. A process developed in the light of a need which arose relatively shortly before the application is not deemed to involve inventive step if this need could be readily met by an obvious combination of teachings from the state of the art.
II. When examining for inventive step, the state of the art must be assessed from the point of view of the man skilled in the art at the time of priority relevant for the application. Consequently all previously published embodiments must be taken into consideration which offered a suggestion to the skilled practitioner for solving the problem addressed, even where those embodiments were not particularly emphasised.

The full text of the decsion can be accessed here.