Chiba Prefectural Police in Japan have decided to refer a 27-year-old man to the prosecution as of November 20. He is suspected of violating copyright law by using an AI-generated image without the original “creator’s” permission. According to Japanese media, this is the first nationwide case in which an AI-generated image was deemed to qualify as a copyrighted work, and thus its use a potential violation of The Copyright Act.
As reported by Yomiuri Shimbun, the original creator of the image generated it using Stable Diffusion in late August 2024. The suspect appropriated this image and allegedly used it as a cover for a commercially sold book without the creator’s consent.
In a document titled “General Understanding on AI and Copyright in Japan,” Japan’s Agency for Cultural Affairs states that whether AI-generated outputs qualify as creative works depends on a holistic assessment of factors such as the quantity and content of prompts given to the AI and how many iterations were produced.
The AI creator, whose copyright was allegedly infringed upon, told police that he gave over 20,000 prompts to Stable Diffusion when creating the image in question, including several detailed instructions and revisions. Based on this testimony, the police decided to refer the case to the prosecution on suspicion of copyright ingfingement. They will attach an opinion calling for “strict punishment,” effectively recommending indictment.
While there is currently no verdict, attorney Kensaku Fukui, an expert on AI and copyright claims quoted by Yomiuri Shimbun, believes that if the prompts used contain sufficiently concrete and detailed specifications, the output can qualify as copyrighted work. While giving vague instructions to a generative AI tends to lead to diverse and unpredictable results, more detailed prompts can produce images that match the user’s intended vision. In such cases, Fukui says, “What’s crucial is whether the human is giving instructions while being able to specifically anticipate the result.”
