Plausibility and Inventive Step at the EPO - Watch G2/21 live on Thursday 24 November

On Thursday 24 November 2022, the Enlarged Board of Appeal (EBA) will hear the parties in case G2/21 on plausibility. Based on the Board’s preliminary views, commentators seem to have settled on the expectation that plausibility is here to stay, albeit in its milder and more innovator-friendly version. Accordingly, a technical effect that is not shown to be ab initio implausible can be made credible by post-published evidence in order to be taken into account by the deciding body for the assessment of inventive step.

Many have expressed great interest in this case. Fortunately, the EPO will provide the possibility to follow the oral proceedings online via live stream. The link will appear here the day before. The hearing starts at 10am Munich time, 9am UK time.

I will pay particular attention to four points.

  1. While it appears almost unavoidable that the first of the three questions is answered “no”, I am particularly interested in understanding the EBA’s position as regards the Board of Appeal’s previous practice. Have the Boards of Appeal, by disregarding post-published evidence as a matter of principle in case of a finding of lack of plausibility, deprived the parties submitting and relying on such evidence of a basic legal procedural right? In the very end, it was this kind of practice that led Board 3.3.02 to refer the first question.

  2. In expressing its sympathy with an ab initio implausibility test, the EBA suggest that the threshold to be met is not having “any significant reason to doubt”. Obviously, it will be interesting to hear whether the EBA will provide guidance as to when a particular reason is significant. The EBA may have in mind that the assessment of plausibility must be made on a case-by-case basis so that the significance of a particular reason will have to be assessed against the facts of the case at stake.

  3. While a finding of ab initio implausibility might in the future be a relatively rare outcome, there are signs that another strand of existing case law may become more prominent in the EPO’s assessment of inventive step. In its preliminary opinion, the EBA notes that “the technical effect relied upon, even at a later stage, needs to be encompassed by [the technical teaching of the claimed invention from the application as filed] and to embody the same invention”. This seems to allude to the established line of case law that "as a matter of principle, any effect provided by the invention may be used as a basis for reformulating the technical problem, as long as that effect is derivable or deducible from the application as filed. See CLBA I.D.4.4.2. This well-established case law is also discussed in the decision that gave rise to the referral, T0116/18, at 13.7.2 as: "… any effects may be taken into account, so long as they concern the field of use and do not change the character of the invention". I have a feeling that this test may turn into a higher hurdle than it has been hitherto. In my opinion, the referral may result in a lowering of the plausibility hurdle but push the EPO to turn to a test much more similar to the EPO’s strict approach under Article 123(2) EPC in their effort to prevent applicants and patentees from relying on technical effects that the EPO considers inappropriately disclosed.

  4. The EBA does not consider it appropriate to extend the referral beyond the significance of post-published evidence relied upon in respect of inventive step. Is there still a need for another referral to clarify the role of plausibility in the assessment of sufficiency of disclosure?

Watch this space!