On 15 April 2025, the EPO Board of Appeal issued its decision on case No. T 1193/23, concerning the interpretation of the technical claims of a patent consisting of a safety mechanism for rotor spinning machines. In particular, the patent’s novelty depended on the interpretation of its technical claims compared to those of a priorly disclosed invention. The patentee argued that the disputed claims did not fall within the scope of the prior invention, claiming that artificial intelligence tools confirmed this interpretation when questioned about the meaning of such claims. The Board of Appeal revoked the patent, arguing that the answers provided by artificial intelligence tools do not necessarily reflect the understanding of a skilled person in the relevant technical field and at the relevant time, in that such answers may vary depending on multiple factors (such as the context and exact formulation of the questions) and are based on training data unknown to the user, and therefore, could not be used alone to interpret a patent claim.