In a leading decision dated 29 July 2025 (Case No. X ZR 99/23), the Xth Senate of the Federal Court of Justice (BGH) commented on the determination of the state of the art.

The decision focused on how to assess the disclosure of presentation slides used to illustrate a public workshop and provided to participants as printouts.

The BGH clarified that the disclosure of such slides must be assessed independently of any additional restrictive information provided during the presentation.

This reasoning is logical and relevant to practice: While oral explanations may shape the understanding of those present, they are not accessible to individuals who did not participate in the workshop and merely received the slides.

As the workshop was open to the public and the participants were not subject to any confidentiality obligations, the slides were deemed part of the state of the art from the date of the event.

In this case, this related to a patent for the automated detection and robot-assisted processing of defects in a workpiece surface. The plaintiff had challenged the patent on the grounds of lack of patentability. The Federal Patent Court invalidated the disputed patent, and the BGH has now dismissed the appeal against that ruling. The content disclosed in the presentation slides (D14) played a key role in the assessment of inventive step.

This decision highlights the importance of careful documentation and handling of publications prior to patent applications. Information made publicly available, including in the form of presentation slides, can influence the prior art, even if verbal restrictions have been imposed.

In summary, this decision underscores the absolute necessity of deliberate and strategic handling of information prior to filing a patent application. Any public disclosure, even in the form of presentation slides at a workshop, can have far-reaching consequences for the patentability of an invention.