Interview with Thomas Wolter on Plausibility and G2/21 - part II

Jean-Claude: What were your first thoughts when the Enlarged Board of Appeal published its decision in G 2/21? Did you find the decision "plausible"...?

Thomas: My first thoughts? I read the two headnotes and felt relieved and intrigued at the same time. Relieved because the decision clearly permits, in the context of inventive step, the reliance on post-filed evidence to prove a technical effect whose occurrence is disputed. Intrigued because the headnotes do not mention words like plausibility, plausible or implausible at all.

"...of utmost importance to disentangle the topic of evaluation of evidence from the substantive assessment of a technical effect in the context of a patent application."

The decision was not a quick read. Its first part is about the principle of the free evaluation of evidence. Here, the Enlarged Board gives clear-cut guidance. Its second part is, however, much more difficult to understand. I think the Enlarged Board felt it was of utmost importance to disentangle the topic of evaluation of evidence from the substantive assessment of a technical effect in the context of a patent application. I can see why the Board wanted to move away from the concept of plausibility and give a face-lifting to the substantive assessment of whether a given technical effect can be relied upon for the purpose of inventive step. The concept of plausibility had been perceived as conflating the issue of “proof” with the substantive assessment of the technical effect.

Jean-Claude: The EBA considered that the term "plausibility" did not amount to a distinctive legal concept or a specific patent law requirement under the EPC. Would then mean that plausibility is "dead"?

Thomas: This is a good question. Having followed various commentators over the past weeks there is clearly a divide between two camps. One the one side, those who believe that at least in the context of inventive step plausibility is no longer the concept that we are going to refer to in the future when assessing whether patentees and applicants can rely on post-filed evidence to prove a technical effect. On the other side, those who believe that nothing has changed and the gist of plausibility will continue to survive if even its use as a catchword may have fallen out of favour. I am used to be on the innovators’ side and have a structure in mind that will help me to navigate this space on behalf of my clients. However, I am also curious to see how those challenging patents will approach this topic and try to make of use G2/21 in their favour.

Jean-Claude: By which criteria "plausibility" is going to be replaced, and what does that mean in practice?

Thomas: The wording that we see in headnote II does not come out of nowhere. The same words were already used by the Enlarged Board at point 15 of their preliminary opinion that was issued in October last year. During the oral hearing in November, I remember that the questions posed by the Enlarged Board made me think that the Board, while leaning strongly in favour of the ab initio implausibility approach, had not yet agreed on a user-friendly definition of what is meant by ab initio implausibility and how it is to be applied. Perhaps, the questions posed during the hearing were meant to encourage the parties to turn towards the criteria that are now set forth in headnote II.

Most commentators including me were expecting the Enlarged Board of Appeal to choose the ab initio implausibility middle ground and decide that a technical effect that is not shown to be ab initio implausible, can be made credible by relying on post-published evidence. And many of us were hoping to get even more guidance as to what it means for the skilled person to have any significant reason to doubt that the purported technical effect is achieved.

"...looks like a quite convoluted set of criteria."

However, the remarks about significant reasons to doubt in the preliminary opinion did not make it into the final decision. What we now have looks like a quite convoluted set of criteria. The Enlarged Board itself does not provide much guidance as to what it means for an effect to be derivable as being "encompassed by the technical teaching" and to be "embodied by the same invention". The use of the word “derivable” in connection with the application as filed and the skilled person, having the common general knowledge in mind, of course looks familiar to EPO practitioners. However, the full wording of headnote II appears to have been carefully drafted by the Enlarged Board so as to allow applicants and patentees to rely upon technical effects that are not disclosed as such in the application as filed.

Headnote II is reminiscent of a well-established line of EPO case law; that is, for a technical effect to be taken into account in the assessment of inventive step, it must be derivable or deducible from the application as filed. There is scarce explicit guidance in the decision to support the view that they meant to refer to said established line of EPO case law. However, at point (93) of the EBA’s decision there is a remark that can be understood to affirm this view. I understand the Enlarged Board to say that a technical effect that is encompassed by the technical teaching and embodies the same invention is an effect that does not change the nature of the claimed invention. Not changing the nature of the invention would represent a relatively low bar to be met. Moreover, I have noted that the referring decision too discusses the same line of established case law at point 13.7.2 of the Reasons. They refer to the “spirit” of the invention which I would think is meant to be synonymous with the “nature” or “character” of the invention. Interestingly, the referring Board does this as part of the arguments that generally speak against a plausibility requirement. Perhaps this is another hint that the criteria set forth in headnote II are meant to bring us back to an existing line of case law while abandoning the concept of plausibility altogether.

"...assessment of plausibility or implausibility was always strongly case dependent..."

The development of this part of the case law will be interesting to watch over the next years. We all have to keep in mind that the assessment of plausibility or implausibility was always strongly case dependent, and I expect the same to be true to some extent when comes to applying the criteria set forth in headnote II of G2/21.

Jean-Claude: Are the questions around "plausibility" settled for now, or what could/should the EBA have considered in the decision?

Thomas: Well, I expect that there will be a shift away from discussing plausibility. However, we do not need to have a crystal ball in order to see that the criteria of headnote II leave room for interpretation and will trigger a lot of questions and discussions.

I believe the decision has been widely received with disillusionment. Instead of providing specific guidance and select from among the three divergent lines of case law identified by the referring Board, the Enlarged Board of Appeal has taken a step back and settled for providing abstract criteria that they say somehow fit on all previous cases the Board has looked at. So, it will take some time before the trends as to how G2/21 is applied by the EPO will become apparent. On the other hand, it might have been a smart move by the Enlarged Board to keep their guidance on an abstract level, which could offer chance to get rid of unfortunate case law and take at a fresh look at when applicants and patentee can rely on post-filed evidence to persuade the deciding body that a particular technical effect is achieved.

Jean-Claude: As I am about to set up a training on plausibility with you, Amanda Ebbutt and Victoria Coleman , what can attendees expect to master after the course?

"...provide attendees with a structured toolbox that helps them mastering contentious issues in relation to technical effects."

Thomas: G2/21 has not made the EPO practitioner’s life easier. The abstractness of the criteria set forth by the Enlarged Board of Appeal require due consideration. In the training you mention we will explore G2/21 in all its aspects and then re-engineer a number of past cases and their outcomes against the guidance given in G2/21. Attendees can expect to see both sides, the innovator-friendly approach and what opponents in the EPO will try to make out of G2/21. The objective is to provide attendees with a structured toolbox that helps them mastering contentious issues in relation to technical effects. This includes tips on how to draft patent applications with a view on reducing exposure to challenges that might be derived from G2/21.

Jean-Claude: Thank you for your time.

Thomas: My pleasure. Thanks for having me.

About the interviewee: Thomas Wolter qualified as German and European Patent Attorney in 1999 and has practiced at a German patent law firm before joining Mewburn Ellis in 2020. He is particularly interested in plausibility. Thomas represented the patentee in the dasatinib cases at the EPO, gave presentations about plausibility, and ran a workshop on plausibility at the FICPI World Congress 2022. He has a double Master’s degree in chemistry and biology from Ruhr-Universit?t Bochum, Germany, and a PhD from Université Louis Pasteur Strasbourg, France.