T 1090/21 - Breadth of claim and closest prior art

Key points

•  "On the question of whether only one piece of prior art should be selected for the purpose of assessing inventive step, it is settled case law that there are often several reasonable starting points, each offering a different route that might lead to the invention without the need of hindsight (see Case Law, I.D.3.1). In that case, the rationale of the problem and solution approach requires that the invention be assessed relative to all these possible routes, before an inventive step can be acknowledged, even if in some cases the number of routes might be substantial."

• "For example, the number of suitable prior art documents may depend on the breadth of a claim, so that a broad claim may lead to a situation where several documents are equally valid starting points. The same is true in a highly competitive technical field where many closely related prior art documents have been published. However, as mentioned above, the fact that several documents are proposed as the closest prior art is not incompatible with the problem-solution approach."

•  "For these reasons, the Board considers that D19, and in particular its example 4, is a reasonable starting point for assessing inventive step."

• The claimed subject matter of the request is found to be obvious. Turning to an auxiliary request, the Board notes the following: "the Board cannot follow the respondent's argument that, given the large number of possible starting points, it could not be required to provide evidence of effect in each case. As noted previously (see point 1.1.5), the number of suitable prior art documents may, for example, depend on the breadth of a claim, so that a broad claim may lead to a situation where several documents are equally valid starting points. The same applies in a highly competitive technical field where many closely related prior art documents have been published. In such a situation, the Board considers that it would be an unjustified advantage to exempt an applicant or proprietor from providing evidence of a technical effect merely because the claims are broad and/or the number of possible starting points is relatively high."

• Turning to a further auxiliary request: "According to established case law, the objective technical problem must be derived from effects directly and causally related to the distinguishing features of the claimed invention. In particular the comparison with the closest prior art has to show convincingly that the effect is attributable to the feature distinguishing the invention. The aim of such a comparison is to demonstrate that the technical effect has its exclusive origin in the feature characterising the invention in the claims" 

• "the question to be answered is whether a technical effect can be inferred from the available experimental evidence that is related to distinguishing feature (iii), i.e. the presence of a fast-reacting crosslinker and a slow-reacting as defined in claim 1 (instead of the fast-reacting crosslinker as disclosed in D19)."

• "In order to provide evidence of an effect over the closest prior art, the parties do not necessarily have to reproduce embodiments of the closest prior art. It is true that, according to the boards' established case law, tests comparing the invention with the prior art have to be conducted in such a way that any effect can be attributed to the distinguishing feature. However, it is also permitted - and might even be necessary - to modify prior-art embodiments in line with the invention to such a degree that the only remaining difference was the feature distinguishing the claim"

• This claim request is held to be inventive.

EPO 

The link to the decision is provided after the jump, as well as (an extract of) the decision text.

https://www.epo.org/en/boards-of-appeal/decisions/t211090eu1

1.1 Closest prior art

1.1.1 The appellant considered that example 4 of document D19 could be selected as the closest prior art for the subject-matter of present claim 1.

1.1.2 The respondent, in agreement with the opposition division, held that D13 and not D19 was the closest prior art for operative claim 1. In particular, it was pointed out that D13 had more in common with the invention of the opposed patent than the other cited prior art. While documents such as D19 used a "chemical" approach to the preparation of silicone hydrogels, D13 took a "processing" approach using visible light and UV absorbers similar to the one claimed the patent. In addition, the opponent had presented eight possible starting points in their notice of opposition. To use these multiple lines of attack based on numerous alternative starting points ("shotgun approach") would not be the way in which the problem-solution approach should be applied.

1.1.3 Irrespective of whether or not D19 is closer to the subject-matter of claim 1 than D13, the relevant question for the Board is whether D19 represents a realistic starting point for a skilled person aiming at the claimed invention (see Case Law of the Boards of Appeal, 10th edition, 2022, hereinafter "Case Law", I.D.3.4.1). In that respect, a central consideration in selecting the closest prior art is that it must be directed to the same purpose or effect as the invention (see Case Law, I.D.3.2).

The opposed patent pertains to silicone hydrogels for use in contact lenses (see paragraphs [0001] and [0002]). In view of the fact that D19 is directed to the same purpose (see D19, paragraphs [0029] and claim 15), the Board is of the opinion that D19 is not an unreasonable starting point and can therefore be chosen as springboard to analyse inventive step of the subject-matter of claim 1.

1.1.4 Moreover, in response to the respondent's arguments, the Board does not see a clear distinction between the so called "processing" and "chemical" approaches. Indeed, it was not disputed by the parties that the monomer formulation (and therefore the "chemistry") influences the kinetics (and therefore the "process" in the sense of the respondent). Although D19 does not necessarily mention that the hydrogel is obtained by controlling the kinetics, it cannot be denied that the monomers used in the formulations of D19 have different reactivities so that the kinetics must have an effect on the hydrogel structure. In other words, it is not because D19 does not use the term kinetics that kinetic phenomena do not occur or are not relevant in the formulations disclosed therein.

1.1.5 On the question of whether only one piece of prior art should be selected for the purpose of assessing inventive step, it is settled case law that there are often several reasonable starting points, each offering a different route that might lead to the invention without the need of hindsight (see Case Law, I.D.3.1). In that case, the rationale of the problem and solution approach requires that the invention be assessed relative to all these possible routes, before an inventive step can be acknowledged, even if in some cases the number of routes might be substantial.

For example, the number of suitable prior art documents may depend on the breadth of a claim, so that a broad claim may lead to a situation where several documents are equally valid starting points. The same is true in a highly competitive technical field where many closely related prior art documents have been published. However, as mentioned above, the fact that several documents are proposed as the closest prior art is not incompatible with the problem-solution approach.

1.1.6 For these reasons, the Board considers that D19, and in particular its example 4, is a reasonable starting point for assessing inventive step.