Navigating the EPO’s “problem-solution approach”— Part III
Previously in this series we have learned how the European Patent Office (EPO) selects the closest prior art in the context of the problem-solution approach for assessing inventive step. A further important step in the problem-solution approach is the definition of the objective technical problem, which serves as a basis for how the notional skilled person analyses the prior art with regard to obviousness.
The formulation of the objective technical problem first requires the identification of the differences between the disclosure of the closest prior art and the subject matter of the claim, i.e. the determination of the distinguishing technical features. The distinguishing features must be technical features in the sense that they make a contribution, either independently or in combination with other features, to the technical character of the invention. Purely non-technical features that do not make a contribution to the technical character of the invention are not taken into account for the assessment of inventive step. Once the distinguishing technical features have been determined, one identifies the technical effects that result from these distinguishing technical features. Technical effects that are only derived from features that are also disclosed in the closest prior art cannot serve as a basis for formulating the technical problem.
While in principle the EPO requires that the technical problem is formulated as the aim or the task of modifying or adapting the closest prior art to provide the technical effects that are derived from the distinguishing technical features. In reality, there is a wide range of possible formulations of the objective technical problem, depending on the circumstance of the case. However, a crucial limitation for the formulation of the technical problem is that the problem must not contain pointers to the solution, i.e. the subject matter of the claim, to prevent an ex post facto analysis. In particular, the technical problem should not include a pointer to the distinguishing technical features, specifically, it should not explicitly mention them.
Similarly to the selection of the closest prior art, the formulation of the objective technical problem seeks to objectify the assessment of obviousness. Another reason for basing the assessment of inventive step on a technical problem, according to the Boards of Appeal, is that the skilled person does not simply act out of idle curiosity but proceeds with a specific technical purpose in mind. This technical purpose is provided by the objective technical problem.
Based on the general principle that the granted patent monopoly should correspond to the actual contribution to the art, it has been held by the Boards of Appeal that the objective technical problem can only be taken into account for the assessment of inventive step if it is actually solved by the claimed invention over the entire ambit of the claim. For demonstrating that the technical problem has been actually solved, i.e., that the technical effect underlying the technical problem has been actually achieved, the applicant may include experimental data in the patent application. For instance, for pharmaceutical inventions, patent applications regularly contain in vitro or in vivo data that demonstrate a therapeutic effect.
However, at the point of drafting the application the relevant technical effect for establishing inventive step over cited prior art may not even be known or the relevant data may not yet be available. In these cases, applicants and patent proprietors often have to rely on post-published evidence in support of the technical effect in examination or opposition proceedings.
A large body of case law has been developed over recent years, defining under which circumstances such post-published data can be taken into account for establishing an inventive step, i.e. for demonstrating that the objective technical problem has been solved. Without summarising this case law in detail, in principle the standard that has been developed by the Boards of Appeal is that post-published data can support an inventive step if it already has been plausibly shown in the original filing documents that the objective technical problem is solved, in particular if there are doubts that the invention can solve the objective technical problem (see, e.g., T 1329/04 and T 578/06).
This jurisprudence recently culminated in decision T 116/18 of the Technical Board of Appeal 3.3.02, in which the Board decided to refer the following questions to the Enlarged Board of Appeal:
If for acknowledgement of inventive step the patent proprietor relies on a technical effect and has submitted evidence, such as experimental data, to prove such an effect, this evidence not having been public before the filing date of the patent in suit and having been filed after that date (post-published evidence):
1. Should an exception to the principle of free evaluation of evidence (see e.g. G 3/97, Reasons 5, and G 1/12, Reasons 31) be accepted in that post-published evidence must be disregarded on the ground that the proof of the effect rests exclusively on the post-published evidence?
2. If the answer is yes (the post-published evidence must be disregarded if the proof of the effect rests exclusively on this evidence), can the post-published evidence be taken into consideration if, based on the information in the patent application in suit or the common general knowledge, the skilled person at the filing date of the patent application in suit would have considered the effect plausible (ab initio plausibility)?
3. If the answer to the first question is yes (the post-published evidence must be disregarded if the proof of the effect rests exclusively on this evidence), can the post-published evidence be taken into consideration if, based on the information in the patent application in suit or the common general knowledge, the skilled person at the filing date of the patent application in suit would have seen no reason to consider the effect implausible (ab initio implausibility)?
This referral is now pending before the Enlarged Board of Appeal with the case number G 2/21.
As can be seen from the referred questions, the key issues are whether post-published evidence can be disregarded at all for assessing inventive step, considering the principle of free evaluation of evidence. And if the post-published evidence in principle can be disregarded, in standing with the case law of the Technical Boards of Appeal, what are the requirements for taking into account post-published evidence for inventive step, the presence of “ab initio plausibility” or the absence of “ab initio implausibility”?
Given the long line of case law on the relevance of post-published evidence on inventive step, it seems rather unlikely that the Enlarged Board will answer the first question in the negative (of course, provided that Enlarged Board answers the questions as they were presented). However, it will be interesting to see whether the Enlarged Board will emphasise the applicant’s burden to positively show in the original filing documents that the problem is solved—a problem that the applicant might not even know at the date of filing—or whether the Enlarged Board will put more weight on the absence of serious doubts that the invention solves the problem.
In any case, the decision of the Enlarged Board in G 2/21 will be of great relevance for the EPO’s assessment of inventive step. We will keep you updated.