By Attorney & Patent Attorney Masatoshi Tanaka

1.The Significance of Copyrightability of AI-Generated Works

The use of AI to create designs, music, and other works has become increasingly common. Accordingly, whether these outputs qualify as “copyrightable works” has become a significant issue. For example, if an individual creates a design or piece of music using AI and the copyright is recognized, then that individual could exercise rights, including collecting licensing fees when others wish to use it, or seeking injunctions and damages if it is copied or modified without permission. However, it may be argued that it was not actually the individual, but AI that created the work, so the individual should not have any rights over such work.

Under both Japanese and U.S. law, only humans (or legal persons, like corporations) can hold a copyright. Therefore, if AI alone creates a work, that work is not subject to copyright protection. This question lies at the heart of the U.S. Copyright Office reports and has long been debated in Japan as well.

If a work is determined to have been created by AI and not by an individual, the individual cannot demand license fees or damages, nor can the individual stop others from modifying or using it.

A famous precedent is the 2018 case in the U.S, Naruto v. Slater, often referred to as the ‘Monkey Selfie’ case. A monkey pressed the shutter of the camera to take a selfie, resulting in a striking picture of the monkey. The court held that, since the photo was taken by an animal, neither the monkey nor the human who merely provided the camera could claim copyright. As a result, the photo was not protected under the law.
(See photo: Monkey Selfie, source: Newsweek, Aug 21, 2024)

2.U.S. Copyright Office Report Part 2

On January 29, 2025, the U.S. Copyright Office published its second report: “Copyright and Artificial Intelligence, Part 2: Copyrightability”.’ Although the report is not legally binding, it provides guidance and is expected to influence future interpretation and practice. The core findings of the report are as follows:

(1) Content/works created entirely by AI are not eligible for copyright protection.
(2) If AI is used only as a supporting tool, human contributions may be recognized as copyrightable.
(3) Copyright protects original human expression; AI-generated content/output alone is excluded.
(4) If human contributions are sufficiently substantial, parts of AI-assisted outputs may qualify for protection, but this is judged on a case-by-case basis.
(5) A prompt alone is insufficient to claim copyright.
(6) Human creativity in selecting, adjusting, or editing AI outputs may apply for copyright protection on a case-by-case basis.
(7) At present, no new copyright laws or systems are necessary for AI-generated content.

In other words, AI itself cannot be considered as an author, and its outputs are excluded from protection, even if the human inputs detailed prompts. However, if the human using the AI further refines or edits the AI output that reflects creative choices, it may be recognized as copyrightable work. Similarly, works created with AI as a tool, and not as the sole author, are more clearly attributable to human authorship and are protected. Interestingly, the report also clarified that prompts themselves are generally not copyrightable, because AI interprets them, and the resulting outputs can vary infinitely.

3.Practical Considerations when Using AI for Creative Works

This interpretation leads to a practical warning. If one simply provides a simple prompt, generates multiple AI outputs, and selects the best output, that work will likely not be protected. In such a case, other individuals can copy or modify such work without legal recourse.

On the other hand, if the human provides detailed prompts with a clear creative vision, essentially using the AI as a tool to execute that vision, the result/work is more likely to be protected. Moreover, it is advisable not to use AI outputs as-is, but to finalize them under human direction through selection, adjustment, or editing. This eventually increases the likelihood of protection.

As the report notes, current copyright law is capable of addressing these questions. Unless new technology emerges, the prevailing interpretation that protection depends on meaningful human creative involvement is expected to remain the global standard.

4.Proof of Authorship in AI-Generated Works

In theory, copyright protection depends on the degree of human involvement. The burden of proof lies with the claimant, who must prove their creative contribution. Practically, however, simply publishing a work and declaring ‘I created this’ may suffice, unless someone can prove that AI was the true creator of such work. As a result, even works created entirely by AI may end up being registered or enforced as copyrighted works.

There are cases where large numbers of works suspected of being AI-generated have been registered. For example, the Japanese Society for Rights of Authors, Composers and Publishers (JASRAC) recorded nearly 180,000 new songs in 2023, almost double the figure from three years earlier. This surge was unusual, and many songs were suspected to be AI-generated. In August 2023, JASRAC issued guidelines stating that works autonomously created by AI cannot be registered. Nevertheless, in practice, if an applicant can guarantee authorship, registrations would still be accepted. As JASRAC’s director, Tatsuya Shimatani, explained, if applications are abnormally high, they may inquire regarding the creative process of such work, but ultimately, the system must rely on the applicant’s assurance.

In litigation, the central question would be whether humans truly created the work, but for third parties, proving that the work in question was actually created by AI is extremely difficult.
In conclusion, creators using AI should take precautions by documenting the creative process, retaining evidence of human involvement, and, most importantly, avoiding leaving the entire act of creation entirely to AI.