Sufficiency of disclosure in recent European case law

September 25, 2023

The "whole area claimed" criterion for sufficiency of disclosure is increasingly being applied to inventions in the fields such as mechanics and electrical engineering at the European Patent Office (EPO). We take a look at this criterion and how to mitigate risks associated with it in more detail.

The “fundamental patent bargain” requires a detailed public disclosure of an invention in exchange for a time-limited monopoly on the commercialisation of this invention of a scope defined by the patent claims.

In Europe, the public disclosure is required to be to a level of detail which is sufficiently clear and complete for it to be carried out by a person skilled in the art (Article 83 of the European Patent Convention).

An interpretation of this point of law, developed mainly in the field of chemistry for inventions where a central aspect of the claimed invention is a range of compositions or of parameter values, is that the disclosure must provide sufficient detail to render it apparent to the skilled person how to put substantially any embodiment falling within the scope of the patent claim into practice. This is sometime called the "whole area claimed" criterion. It is closely related to “Biogen Sufficiency” (Biogen Inc. v Medeva plc [1996] UKHL 18) in the UK.

There can be a temptation to believe that the criterion will not apply to the more “predictable” arts of electrical engineering, physics, and mechanics and the application of this criterion to fields other than chemistry has indeed been criticised by some Boards of Appeal of the EPO (e.g., in T 2773/18, T 500/20, and T 1983/19).

However, this view is not shared by all of the Boards of Appeal. The board in the recent decision T 0149/21 saw no reason why this criterion should be restricted to the field of chemistry.

As all European patent practitioners will be aware, it is challenging to overcome sufficiency objections raised by the EPO without impermissibly adding subject-matter into the patent application. Therefore, sufficiency of disclosure needs to be borne in mind when the application is initially drafted. It is useful to consider the facts and the reasoning in T 0149/21 to understand better how to mitigate against sufficiency objections from the EPO.

The patent in T 0149/21 relates to a method for reducing the energy consumption in a rolling mill.

In the event of a malfunction in a rolling mill, breaks in the rolling occur. During these breaks, mill components which are not directly affected by the malfunction are not shutdown and so continue to consume energy. In the event of long breaks, some of these may be manually shutdown at the discretion of the (human) operator, but generally only those which are easy for them to shutdown.

The invention involves:

identifying the type of malfunction that has caused an unscheduled break;

determining an expected duration of the break on the basis of the identified type of malfunction using a controller;

automatically shutting down (or putting into some energy saving mode) the mill components whose combined shutdown and start-up time is shorter than the expected duration of the break, again using the controller.

The specification describes a human operator (“roller operator”) manually identifying the type of malfunction and the expected duration being determined using a database (“malfunction matrix”). In regard to the latter, the board takes the view that this means that the expected duration cannot be determined for malfunctions of an unknown type.

The claims are not limited in respect of the former or the latter. The claims therefore (perhaps inadvertently) encompass automatic identification and the ability to determine an expected duration of a break caused by an unknown type of malfunction.

The board found that the patent gave no disclosure which was sufficient to enable a skilled person to implement automatically identification of a malfunction and determination of an expected duration of a break caused by an unknown type of malfunction. Accordingly, the board considered that the claim was not enabled over its whole breadth and that the application was therefore contravened Article 83 EPC.

Though it would not appear to make a difference to the outcome in the present case, it is noteworthy that the board does not appear to have made a distinction between those features relevant to the core inventive concept of the claimed invention and those which are not.

For instance, the means or method of identifying the malfunction does not appear to represent a deviation from existing mill shutdown procedures. In those, as in the present case, the malfunction is identified by the human operator. How the malfunction is identified therefore does not appear to be part of the contribution to the art made by the claimed invention. It seems as though a harsh enablement standard has been applied in respect of this feature.

On the other hand, the determination of the expected duration of the break on the basis of the type of malfunction does appear to be at the core of the contribution made by the invention. It seems unlikely that shutting down those mill components which can be shutdown and started back up within an expected duration of an unscheduled break would be commensurate with the actual contribution made. For one, in the abstract, this seems rather obvious (if not already known). It seems, rather, that the actual contribution would be how this could be automated. And in that regard, how the expected duration is determined does seem to be essential.

If the invention only needed to be disclosed over the whole scope of the claim with respect to features relevant to the core inventive concept of the claimed invention (as is the case in the UK e.g., Illumina Cambridge Ltd v Latvia MGI Tech SIA & Ors [2021] EWHC 57 (Pat)), then perhaps the patent could have survived with claims drafted to include something along the lines of:

identifying the type of malfunction that has caused an unscheduled break;

determining whether the type of malfunction corresponds to an entry in a database, which associates types of malfunction with expected durations of a break;

if the type of malfunction corresponds to an entry in the database, determining an expected duration of a break from the database on the basis of the identified type of malfunction

Unfortunately, making such a distinction between features in the application of "whole area claimed" criterion does not appear to be a practice which is widely adopted by EPO.

While it will often be worth arguing that such a distinction should be applied or even that the "whole area claimed" criterion should not be applied at all in certain fields of technology, it would appear sensible to ensure that patent applications which are intended to be filed in Europe are drafted bearing in mind that the "whole area claimed" criterion may be applied in respect of all features of the claims.

In the present board’s view, all technically reasonable choices for a feature in the claims should be enabled by the patent application.

Therefore, when drafting, it is recommended that the scope of terms used to define a feature should be considered in terms of the technically reasonable choices it encompasses and, if there is doubt that working of the invention with any of these may be enabled, then thought is given to generating fallbacks which enable the exclusion of such choices for which there may be doubt.