BGH on Using Cancerogenic Substances

Incentive to use?

In the decision “Glasfasern”, the German Bundesgerichtshof (BGH) had to rule in the novelty and inventivess of a “use” claim. The patent had been granted on the idea of using a particular kind of glass fibre material as glass fibre “not having cancerogenic potential”.

The glass fibre as such was (besides of some very minor differences not giving rise to an inventive step) known from at least one document in the prior art. In the same document, it was noted that the glass fibre would presumably have cancerogenic properties (in particular when  minute fragments accumulate in the lung of workers using the material for building insulation) and that two independent institutes had been entrusted to carry out an investigation on this issue.

According to the established case-law in Germany, the anticipation of “use” claims does not require evidence that the “use” has actually taken place. Rather, it is sufficient if the product or substance has been evidently prepared (“sinnfällig hergereichtet”) for such a use, e.g. by using a design adapted to that use or by supplementing the product or substance with a user manual or package leaflet disclosing the possible use.

In the case at issue, the presumption of cancerogenic properties was not considered sufficient to establish a lack of novelty.

Further, this presumption together with the information that studies in this regard had already been commissioned did not constitute an incentive for the skilled person to carry out these (expensive and complex) studies by himself.

An interesting point in this decision is that the “use” was not limited to a particular technical application of the glass fibre such as building insulation but rather covered all applications where cancerogenic potential was undesired (difficult to imaging where this is not the case). The discovery of a yet unknown property (here: lack of cancerogenic potential) of a known substance gives the discoverer the exclusive right to use the substance in applications where this property is relevant.