When evaluating the patentability of claims, the question often comes up of how to deal with documents revealing prior art the disclosure of which does not seem to be reproducible. A recent nullity decision by the Xa. civil senate of the BGH (Federal Supreme Court, Bundesgerichtshof) shows nicely how to proceed in this case: The question of whether or not prior art is reproducible plays no role when determining the novelty of an invention. However, documents revealing non-reproducible prior art are to be disregarded for the evaluation of the inventive step.

The specific example concerned the fabrication of plastic components with cavities. The attacked patent in suit was protecting a method by which good surface quality of the component was realized through a process in which the molding material was pressed out against a counter pressure profile, such that a plug formed in the injection nozzle. With the exception of the creation of the counter pressure profile, all aspects of the procedure to be protected were found in a previously published French patent.

The Federal Patent Court (Bundespatentgericht) issued a declaration of nullity against the patent in suit, since a skilled person would be expected to adapt the teaching disclosed in the French document to inevitably create a counter pressure profile. Furthermore, the formation of a plug was also anticipated by a US patent.

During the appeal, the BGH consulted an expert who concluded that the procedure disclosed in the French publication could not work. It was taken from the technical field of shaping metals but could not be transferred to molding plastics due to the difference in viscosities. – The BGH concluded the examination at that point. In contrast to the Federal Patent Court, it did not consider possible thoughts of a person skilled in the art or combinations with other disclosures. The underlying thought was that a skilled person would realize that the invention could not work, and subsequently dismiss it, at the latest when attempting to reproduce the disclosed invention.

According to the examination system of the BGH, shortcomings of the prior publication do not come into play during the determination of novelty, however. This makes sense, since if the subject of the patent is reproducible, it must contain at least one aspect that distinguishes it from the non-functioning prior art.

For future practical considerations, it should be noted that only the opinion of the consulted expert helped the patent holder on the path to success. According to the new procedural law for nullity actions, in effect since one month, experts are no longer regularly consulted during the appeal process, as was previously the case (see contribution from 10/01/2009). Rather, questions like reproducibility and prior art generally need to be addressed in the court of the first instance. For such cases that means the added expenditure of performing experiments and seeking expert opinions, in order for the parties to convince the technical judges of the nullity senates of the Federal Patent Court.