Patents
Posted on 25/8/2022

G2/21 referral – Plausibility

We consider the G2/21 referral currently pending before the European Patent Office.

There are currently three referrals pending before the European Patent Office’s (EPO’s) Enlarged Board of Appeal (EBoA). This article looks at the earliest of these referrals – G2/21 – made by a Technical Board of Appeal.

The G2/21 referral centres around the filing of evidence to support an application, particularly evidence filed after the application in question is filed.

It is common in the prosecution of chemical and pharmaceutical patent applications to file evidence (such as experimental data) to support arguments that the invention in question possesses an inventive step.

In such cases, the data is filed to show that the technical effect achieved by the alleged invention is unexpected, which therefore indicates that the invention would not be obvious to the skilled person.

However, merely being unexpected is not the only requirement for such data to overcome obviousness objections. It is seen in various cases decided by previous Boards of Appeal that the technical effect must also be plausible. However, in the EPC itself, there is no mention of plausibility, and so the exact standard of plausibility required is hard to establish, as all previous definitions of said standard are dependent entirely upon individual decisions of various Boards of Appeal. As such, a decision of the Enlarged Board will hopefully settle this matter and give a definitive standard for plausibility.

The Referred Questions

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)?

Analysis

The first question relates to whether or not it is permissible to rely on evidence published after the filing of the application, when the only evidence for the inventive effect is in said evidence. In many cases, applicants are limited in their ability to argue for inventiveness to what is disclosed in the application as filed. This question seeks to establish if this is also the case for evidence published after the filing of the application. In many cases, patent applications are filed before all of the test data can be accumulated. A negative answer to this question would greatly impact many cases where data obtained after filing is important to demonstrating an advantageous technical effect.

The second question is dependent upon the first question, in the event where it is not permitted to rely only on post-published evidence. The second questions seeks to clarify that if it is not permitted to rely only on post-published evidence, can the evidence be relied upon if the skilled person would find the inventive effect plausible at the filing date of the application?

The final question mirrors the second, in that it is only relevant if the first question is answered such that it is not permitted to rely only on post-published evidence. The third question seeks to clarify whether the post-published evidence can be relied upon if there is no reason to consider the effect implausible in the application as filed.

These questions could have significant ramification on the usefulness of post-published evidence, as they could be answered raise, lower, or even remove the plausibility requirement within the established case law.

Whilst this is not commonly seen in the mechanical and electronic fields, this referral could have massive implication for the prosecution of chemical and pharmaceutical patent applications.

As always, we shall keep you updated of any decision in this referral, and of any other referrals to the Enlarged Board, if you have any questions please contact us to speak to one of our patent attorneys.

Wilson Gunn