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Case law 25 Oct 2021

Sufficiency of disclosure: inventions in the mechanical vs chemical field

In this case, the Board discusses an alleged insufficiency of disclosure in the mechanical field. The invention relates to a wind turbine with a cooling device that takes in outside air at an elevation where the air has low water and salt content. According to the opponent, the invention is not disclosed sufficiently over the whole claim scope, because the air intake is defined as located in “the upper part of the tower” while a minimum height for the upper part is not specified. According to the Board, this argument misapplies case law developed in the field of chemistry for range-based inventions wherein the effect may not be proven for large parts of the range. In mechanics, claims often are defined in functional terms allowing the skilled person for some breadth of interpretation.
Drawing outside air with a low water and salt content
The appellant -

The patent relates to a wind turbine with a cooling device which uses outside air. According to the Board, the solution in claim 1 relies on a tower comprising an upper part, a middle part and a lower part wherein the cooling device guides outside air from an inlet located in an upper part of the tower into the lower part of the tower. In this way, the outside air passes via the middle part thereby cooling the heat generated by equipment located there.

The lack of sufficiency of disclosure objection raised by the appellant relates to the expression "upper part of the tower" of claim 1 which is defined in paragraph 022 of the patent as “the part of the tower located above the sea spray zone”.

According to the appellant the claim did not provide minimum size or height dimensions for the lower and upper parts of the tower. In this way, the claim comprises embodiments wherein the inlet is quite low above the sea level and this would not allow to achieve the claimed technical effect of “drawing outside air with a low water and salt content”.

However, the Board, considered this argument as an incorrect application of case law developed in the field of chemistry for inventions related, for instance to compositional ranges wherein the associated effect may not be proven or plausible for large parts of that range.

 According to the Board, claims in the field of mechanics often define mechanical structure (or its operation) in functional terms such that some breadth of interpretation is allowed. In this way, it may be that “on clever construction subject-matter can be found to be covered within that breadth that may not solve the problem or achieve the desired effect”. But according to the Board, this should normally not be an issue of lack of disclosure, which is a purely technical question, but rather of claim construction.

Indeed that inference from the whole disclosure might lead to a more limited construction of the claim.
The Board of Appeal -

In the Board's view:

“if the skilled person upon consideration of the entire disclosure possibly using common general knowledge can infer what will and what will not work, a claimed invention is sufficiently disclosed, even if a broad construction might also encompass what doesn't work. Indeed that inference from the whole disclosure might lead to a more limited construction of the claim.”

According to the Board, in the present case the skilled person, trying to make technical sense of the claim in the context of the whole disclosure, would understand that the idea of the invention is to raise the air inlet in the tower above an already raised position of the heat generating equipment.

The Board also observed that the detailed patent description and figures would provide practical guidance to the skilled person and cited as an example figure 2 in conjunction with paragraph [0019] wherein the inlet is provided above the spray zone Z which is of the order of 30 m above sea level, thereby providing an “exemplary value on the basis of which a person skilled in wind turbine design can find other workable heights depending on the known local climatic conditions of the installation, using routine measures”.

Thus, the Board was of the opinion that the disclosure of the patent would allow the skilled person to identify and disregard locations of the inlet not achieving the sought effect of providing air intake with a low enough salt content.

In view of this, the Board confirmed the Opposition division's positive assessment of sufficiency. The Board also confirmed the Opposition Division's positive assessment of novelty and inventive step.

In view of this, the appeal was dismissed.

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