Japan's Supreme Court refuses the DABUS appeal, leaving a natural person as the only possible inventor

2026-03-04Japan

Supreme Court of Japan, Second Petty Bench (Okamura, J., presiding), decision of March 4, 2026 declining to accept the appeal in the DABUS case, leaving in place Intellectual Property High Court (Second Division), judgment of January 30, 2025, 2024 (Gyo-Ko) 10006 (Shimizu, presiding), affirming Tokyo District Court, 2023 (Gyo-U) 5001 (May 16, 2024)

Japan's Supreme Court, Second Petty Bench, with Justice Kazumi Okamura presiding, decided on March 4, 2026 not to accept Stephen Thaler's appeal in the DABUS case, without giving reasons. Japanese Patent Application No. 2020-543051 entered the national phase from International Application PCT/IB2019/057809, which named the artificial intelligence system DABUS as inventor. When the applicant did not amend the national document to name a natural person, as Article 184-5 of the Patent Act requires, the Commissioner of the Japan Patent Office dismissed the application, and the Tokyo District Court upheld the dismissal on May 16, 2024. The Intellectual Property High Court affirmed on January 30, 2025. Reading the grant provision of Article 29(1) with the employee-invention provision of Article 35 and the requirements of Articles 36 and 66 that the inventor's name be stated and published, it held that the Patent Act "presupposes that the inventor is a natural person," so that no patent may be granted under the current statute for an invention made by artificial intelligence. It held that the inventor's name "is the mandatory information to be stated in a national document," that the Agreement on Trade-Related Aspects of Intellectual Property Rights imposes no obligation to protect such inventions, and that whether to grant them patents "is an issue that requires a discussion for legislation."

What it changesJapan now stands with the United States, the United Kingdom, Germany and Australia, whose courts of last resort have each left in place or imposed a natural-person requirement for inventors, and the Japanese courts have said that any change belongs to the legislature. The practical point in Japan is procedural. The inventor's name is a required entry in the domestic document filed at national phase entry, a defective entry draws a correction order, and an applicant who will not name a human loses the application without examination. For a portfolio that enters Japan from international applications, confirm before the thirty-month national phase deadline that every inventor designation names the people who made the claimed invention, and settle any internal dispute about whether a model rather than an engineer produced a claimed feature before entry, not after a correction order arrives. The Supreme Court gave no reasons, so the High Court's judgment is the authority to cite.

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Burbage Law is the practice of Jon Burbage, a registered patent attorney. 342 United States patents have issued from applications he wrote; the full list is on the Patents page. More about Jon Burbage.

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