No matter where in the world you would like to file a patent application, the key patentability requirements in all jurisdictions are essentially the same: novelty and inventive step (in some places also referred to as non-obviousness). According to these requirements, the invention must not be identical to something that is already available to the public (novelty) and the invention must not be a mere trivial modification of the prior art (inventive step).
The European Patent Convention (EPC), which provides the legal basis for granting European patents by the European Patent Office (EPO), states that an invention shall be considered as involving an inventive step, if having regard to the state of the art, it is not obvious to a person skilled in the art (Article 56 EPC). At first sight, one might justifiably think that therefore the only relevant question for assessing an inventive step is whether the invention is obvious to the skilled person having regard to the state of the art. This is however not what the EPO does for assessing inventive step. Since its inception in 1977, the EPO has established a rather unique approach to assess the presence of an inventive step, by breaking up the one question of obviousness, which is explicitly stated in the law, into three separate questions.
a) What is the closest prior art?
b) Which technical problem does the invention objectively solve vis-à-vis the closest prior art?
c) Would it have been obvious to the skilled person at the relevant date to solve this objective technical problem in a way that falls within the terms of the claims?
This approach is generally called the “problem-solution approach” (EPO Guidelines for Examination, G-VII.5). It is often argued that the roots of the “problem-solution approach” can be traced to Rule 42(1)(c) EPC, according to which the description of the European patent application shall disclose the invention in terms of a technical problem and an offered solution to the problem.
Leaving aside the question of where this approach has its statutory footing, it is important to note that the Boards of Appeal of the EPO over the years have developed this approach in an attempt to provide an objective way for assessing inventive step, avoiding hindsight when considering the prior art. The EPO’s approach tries, what otherwise might be difficult to accomplish, namely to force the person making the assessment into the shoes of the notional skilled person at the relevant date—as it were, when the invention did not yet exist, and from this perspective ask the question whether the invention is obvious over the prior art. Of course, this exercise is a difficult one and prone to subjective elements depending on the person carrying out the analysis. Each step along the way of the “problem-solution approach” aims to take out of the equation this subjective element when assessing inventive step.
While the Boards of Appeal have decided that the application of this approach is not mandatory, they have also repeatedly found that it is the best way of avoiding a subjective ex post facto analysis and therefore in principle the approach should be used. The Boards of Appeal even held that if one exceptionally deviates from this established approach, reasons for deviation must be provided. Furthermore, it is simply a fact that both the departments of first instance of the EPO and the Boards of Appeal in practical life insist on a “problem-solution approach”-analysis when arguing inventive step, whether it is as an applicant during examination proceedings, as a patent proprietor during opposition proceedings or as an opponent. Not following the “problem-solution approach” by the letter is often very much to the detriment of the party involved. Therefore, it is important to familiarize oneself with the general way the “problem-solution approach” works and the peculiarities that come with it.
Navigating the intricacies of the “problem-solution approach” can be a challenging task, even for European patent attorneys, for whom the EPO’s “problem-solution approach” is second nature. Therefore, in the next couple of weeks, I will go in detail through each of the three stages of the “problem-solution approach”, in a series of blog posts at this venue, titled “Navigating the EPO’s “problem-solution approach”—Part I-IV”. Next up: How to find the closest prior art? Stay tuned.