On April 15, 2025, the Board of Appeal of the European Patent Office held in a challenge to a patent that comments generated by ChatGPT do not qualify as the “understanding of a person skilled in the relevant technical field.” It agreed with the appellant that the invention at issue lacked novelty and revoked the patent.
Applicable Law
The European Patent Convention (EPC) forms the basis for granting European patents, which are awarded for “any inventions, in all fields of technology, provided that they are new, involve an inventive step and are susceptible of industrial application.” (EPC, art. 52, para. 1.) An invention is new if it does not form part of the state of the art. An invention involves an inventive step if, regarding the state of the art, the inventive step is not obvious to a person skilled in the art. (Arts. 54, 56.) Persons opposed to a patent grant may notify the patent office within nine months of the publication of the grant. (Art. 99.)
Facts of the Case
The appellant opposed the patent granted by the patent office to the patent holder for a process to safely start or stop the rotor of a rotor spinning machine. He submitted that the patent lacked novelty and did not involve an inventive step. The patent holder, in support of his interpretation of the state of the art, submitted responses received from ChatGPT, a large language model, or LLM.
Ruling
The Board of Appeal annulled the patent office’s decision and revoked the patent. It held that the patent lacked novelty. (Decision, para. 1.) It stated that the interpretation of patent claims must be based on the understanding of a person skilled in the relevant technical field. In its opinion, the proliferation and growing use of chatbots based on large language models and/or artificial intelligence does not by itself support the assumption that a generated response necessarily reflects the understanding of such a skilled person.
It pointed out that generated responses are based on unknown training data and may vary depending on the context and the exact phrasing of the question presented. Proving how a person skilled in the art interprets a term may instead be done by, for example, submitting articles from relevant specialist literature. In this case, the patent holder submitted no such proof to support his interpretations. (Para. 1.1.1.)
Background
The European Patent Organization is an intergovernmental organization separate from the European Union (EU). It was established in 1977 under the European Patent Convention. Patent protection may be obtained in one of the organization’s 39 member states, which include all EU member states, and in one extension and six validation states. The European Patent Office, as the executive arm of the European Patent Organization, grants European patents. Its decisions may be appealed to its boards of appeal. (EPC, art. 21.)
Jenny Gesley, Foreign Law Specialist, Law Library of Congress
June 18, 2025
Read more Global Legal Monitor articles.