Japan's Top Court Rules AI Can't Be Named as a Patent Inventor

Japan’s highest court has held that only a human can be listed as the inventor on a patent application, rejecting attempts to credit an artificial intelligence system as the originator of an invention. The decision settles the question under current Japanese law: inventorship is reserved for natural persons, and an AI, however autonomous its output, does not qualify.

The ruling places Japan alongside courts in the United States, the United Kingdom, and the European patent system, all of which have reached similar conclusions in the wave of test cases seeking to name AI systems as inventors. The consistent thread is that existing patent statutes were written around human inventors and cannot simply be reinterpreted to accommodate machine-generated inventions.

The practical effect is that anyone seeking patent protection for work produced with heavy AI involvement must still identify a human inventor. It also pushes the harder policy question—how, or whether, to reward inventions where a machine did the creative heavy lifting—back to legislators rather than the courts.