A decision by the EPO Board of Appeal provides guidance for patent applicants on the importance of sufficiency of disclosure, and how opponents can mount an attack on this basis. Sufficiency was denied by the Board of Appeal in a product claim directed to a highly digestible hydrolyzed keratinaceous material defined in both terms of composition and technical effect.
This decision gives useful guidance for opponents to mount a successful sufficiency of disclosure attack, and for patent applicants, in drafting applications, how to include experiments which support the claimed invention.
Background to sufficiency
Article 83 EPC requires that the European patent application (or patent) shall disclose the invention in a manner sufficiently clear and complete for it to be carried out by a person skilled in the art. That means, for a product, that the skilled person must be able to produce the claimed product based on information given in the patent and their common general knowledge, without undue burden.
Typically, the patent application (or patent) must disclose at least one way to repeat the invention.
For an opponent to bring forward a successful attack of insufficient disclosure, the opponent must have serious doubts substantiated by verifiable facts that it is not possible to repeat the claimed invention, for example when repeating the examples of the patent does not lead to a product falling within the scope of the claims.
Facts of the case
The sufficiency attack concerned product claim 10 directed to a highly digestible hydrolyzed keratinaceous material, obtainable with the method of any one of claims 1 to 9 and defined by:
- i. amino acid composition reflecting the amino acid composition of the raw material.
- ii. a low amount of decarboxylated amino acids.
- iii. a high amount of a material having a molecular weight of 5000 Da (Dalton) or lower.
- iv. in vitro digestibility of 98% or more in both an ileal and pepsin digestibility test.
None of the examples of the patent achieved all four of these product requirements.
Moreover, the opponent (appellant) reworked examples 5, 7 and 10 of the patent, in an experimental report, and could not achieve the combination of all the features i to iv, although the experiments were carried out closely in line with the details of the patent.
Some of the reworked examples were not carried out at the same scale as in the patent. Examples 7 and 10 were reworked on a scale of 100 g starting material and not 100 kg as in the patent. However, the Board decided that this was immaterial. Whereas sometimes there may be scale-up problems, there was nothing to indicate that there could be a problem scaling down the test. Therefore, the reworked examples at a smaller scale were comparable with the examples in the patent.
The Board also considered that the experiments provided by the opponent were not “designed to fail”.
Furthermore, reworked example 5 used the same amount of product as in the patent, as well as process conditions in line with conditions taught in the patent. The opponent was still unable to achieve features iii and iv.
The Board therefore concluded that the failed attempt to rework the examples raised serious doubts that the claimed product, having the combination of features i to iv can be obtained without undue burden. According to the Board, the patent did not contain sufficient detail for the skilled person to turn these failures into success. The Board considered that features iii and iv may be achieved with common general knowledge by increasing processing time and acid concentration used. However, obtaining features i and ii seemed to conflict with that, so in the Board’s view it was an undue burden for the skilled person to achieve features i and ii and, at the same time, features iii and iv.
The Board decided that product claim 10 failed to meet the requirements of Article 83 EPC.
The patent proprietor filed an auxiliary request deleting the product claims and the method claims were found to be allowable under Article 83 EPC because only features iii and iv were present in the method, and not conflicting features i and ii. The Board considered that the skilled person could turn failure into success and achieve these features by increasing processing time from common general knowledge.
Guidance from this case
From the point of view of a patent applicant or proprietor, this case highlights the importance of demonstrating “at least one way” of achieving the claimed invention. In this case, there should have been at least one example demonstrating a product which achieved all of features i to iv. Even if some attempts to rework the invention failed, there should at least be guidance from the single working invention (all four parameters) how to turn failure into success.
From the perspective of an opponent, the case demonstrates how an attack of sufficiency of disclosure can be successful if the opponent runs experiments to demonstrate that the alleged invention cannot be repeated. Quite often, opponents try to assert that the invention is not repeatable but, without evidence, this kind of attack is likely to fail. While experiments may be time-consuming and costly, they can be powerful in an insufficiency attack. As the Board in this case noted, any experiments run by the opponent should not be designed to fail; they should use the same processing conditions as in the patent in a bona fide attempt to replicate the patent disclosure.
In the present case it would have been burdensome to carry out a 100 kg test, but the Board here seemed to accept that the scaling down does not affect the validity of the results.
It is also interesting to note that the Board of Appeal allowed the proprietor to file a new auxiliary request during oral proceedings before the Board, corresponding to the main request but with the product claims deleted. While this was a late-filed request, the only amendment made was deletion of claims. The decision and minutes in this case do not indicate that the opponents objected to the lateness of this request. While it is a risk to not have all requests filed before oral proceedings with the Board, this indicates the willingness of the Board to admit late filed requests when they just include deletion of claims.
