AI and Copyright Developments in 2025

In 2025, discussions about AI and intellectual property rights continued to be widespread in Japan, as in many other jurisdictions. The following cases relating to AI and copyright have been notable in Japan in 2025. Note that the sources of the cases below are news articles and the authors have not independently verified them for their accuracy.

Major Japanese newspaper companies filed a civil lawsuit against a generative AI business due to copyright infringement and unfair competition

In August 2025, major Japanese newspaper companies announced that they filed civil lawsuits against a US company providing generative AI-powered search services that reproduce plaintiffs’ articles and generate answers involving all or part of the creative expression thereof. The Asahi Shimbun Company and Nikkei Inc. jointly filed a civil lawsuit against the US company (the “Asahi and Nikkei case”), and three Yomiuri Shimbun Group entities filed another lawsuit against the same US company (the “Yomiuri case”). For both cases, the newspaper companies claimed that the generative AI business infringed their copyright by reproducing and storing their articles on their servers (including paywalled articles) without authorisation, and by repeatedly providing answers which included the contents of these articles to its users. For the Asahi and Nikkei case, the newspaper companies alleged that, although the newspaper companies took technical measures to block access from the crawler by using “robots.txt”, the generative AI business ignored them and continued to use the contents of the articles. For the Asahi and Nikkei case, it was also alleged that the generative AI business provided false answers to its users while displaying their companies’ names and their articles as the reference sources, which constitute “unfair competition” under the Unfair Competition Prevention Act of Japan. For both cases, the amount of damages claimed was around JPY2.2 billion (about USD14 million) in connection with the alleged copyright infringement and/or alleged unfair competition, and an injunction was demanded to enjoin the reproduction and delivery of the articles by the said business.

According to the Report on AI and Copyright Issues (published by the Legal System Subcommittee of the Copyright Subdivision of the Council for Cultural Affairs of the Cultural Agency, on 15 March 2024), if the infringer ignores the copyright holder’s technical measures to prevent the reproduction of works for the training of AI, such action may constitute one of the elements whereby the interests of the copyright owner are unreasonably prejudiced.

This is the first case in Japan in which major news media have filed a lawsuit against a generative AI business, and, therefore, future developments in this matter will be closely monitored.

Criminal case regarding reproduction of images created by another person using AI

In November 2025, a case was referred to prosecutors involving a man who had reproduced images that were originally made by another person using a generative AI called Stable Diffusion. The person who made the generative AI output stated that he had provided detailed instructions to the generative AI and entered more than 20,000 prompts, and, therefore, the police determined that the images are copyrightable works and he owns the copyright that subsists in the images. It seems that this case was the first time that Japanese investigative authorities considered AI-generated outputs to be within the scope of copyrightable works. As there have been no cases in which courts have found that AI-generated outputs are copyrightable, if a criminal case is filed with a court, a cardinal legal precedent could be established.

Recent important court precedents on the validity of general tort claims in the absence of copyright protection

Introduction

The issue of whether or not a person can seek compensation of damages under a general tort law when that person cannot make a claim under intellectual property law has long been disputed in Japan. With respect to the issue, the Supreme Court of Japan rendered a ruling on 8 December 2011, with regards to a case where a television company broadcasted a portion of a film whose author is a North Korean citizen (Japan does not recognise North Korea as a state, therefore, such film does not fall under a “work” under the Copyright Act of Japan), that an act of using work that does not fall within any of the categories of works under the Copyright Act of Japan does not constitute a general tort unless there are “special circumstances”, such as the infringement on any legally protected interest by the said act other than the interest to be enjoyed through the use of works that are subject to regulation under the Copyright Act (“Supreme Court Judgment”). Following the Supreme Court Judgment, almost all of the lower courts have denied general tort claims where the court did not find an infringement of intellectual property rights. However, more recently, there have been some cases where courts have affirmed general tort claims even when a plaintiff was not protected by the Copyright Act.

“Band Score” case (Tokyo High Court Decision on 19 June 2024)

In this case, the defendant had purchased about 600 band scores (musical scores for band music containing performance information for all parts, including vocals, guitar, keyboard, and drums) made by the plaintiff, produced band scores closely resembling those made by the plaintiff, and then published them on the website for free without the plaintiff’s authorisation. The main issue of this case was whether or not the defendant’s acts constituted a tort under the Civil Code of Japan.

The Tokyo High Court firstly stated that band scores do not constitute works protected under the Copyright Act of Japan. The said court then cited the Supreme Court Judgment, ruling that for a tort to be established, “special circumstances” are needed, such as the infringement on any legally protected interest by the acts other than the interest to be enjoyed through the use of works.

The court further pointed out the following facts. Firstly, producing band scores requires the labour-intensive process of transcription, which includes listening to performances of band music pieces and transcribing them into scores. Secondly, permitting the act of free-riding on the substantial time, effort, and costs for making transcriptions could lead to a decline in sales of commercially available band scores, preventing band score producers from sufficiently recouping their investment in transcription-based production, which would significantly undermine the incentive to produce such scores, potentially eliminating producers altogether and thereby cutting off the supply of transcribed band scores. Thirdly, permitting free-riding on transcribed works would discourage individuals from investing substantial time, effort, and expense to master transcription skills, which would cause the number of individuals transcribing band scores to decrease, and also impair the production of all musical scores produced through transcription, potentially resulting in the decline of the music publishing industry itself and hindering the development of musical culture.

Based on the above facts, the court concluded that the defendant’s act of producing and selling band scores by imitating others’ band scores infringed the plaintiff’s legally protected interest other than the interest to be enjoyed through the use of works, and, thus, the court found the existence of the “special circumstances” referred to in the Supreme Court Judgment, given that the act was (i) an act of free-riding on the time, effort, and expense invested in transcription, as well as the time, effort, and expense required to acquire highly specialised transcription skills, (ii) competitive behaviour in the market for profit that harms fair and free competition, and (iii) an act of business interference that harms another’s business interests by maliciously poaching customers.

“Shogi (Japanese Chess) YouTuber” case (Tokyo District Court Decision on 21 May 2025)

In this case, the defendant, a YouTuber, watched live the paywalled streaming of professional shogi (Japanese chess) games by a newspaper company, obtained live information related to the games, and streamed his own live videos that reproduced moves on a shogi board almost simultaneously with the paywalled streaming. Japan Shogi Association and the newspaper company filed a lawsuit to claim damages against the defendant due to the infringement of their business profit by the defendant’s act under a general tort claim.

The Tokyo District Court firstly noted that the plaintiffs did not argue that making records of shogi games constituted works protected under the Copyright Act. The said court cited the rule established by the Supreme Court Judgment and pointed out that, although business interests represent a legally protected interest other than the interest to be enjoyed through the use of works, it is not appropriate to immediately deem the unauthorised use of information acquired by one person in one’s own business operations, which compete with that of another person, as constituting a tort under the Civil Code of Japan. The court ruled that the “special circumstances” exist only when such use exceeds the scope of permissible free competition, taking into consideration the necessity of protecting the other person’s business interests, the nature and extent of the disadvantage suffered by the victim due to the use, and the purpose and manner of the use.

As for applications of the rule above, the court pointed out the facts below. Firstly, providing professional shogi games requires costs and efforts such as the payment of contract fees by the sponsoring newspaper company, expenditure on various PR activities, various co-ordination efforts by Japan Shogi Association, and payment of prize money. Secondly, the plaintiffs generate income through the licensing of game records and broadcasting of tournaments, and the defendant also made profits from streaming game records on YouTube, and, therefore, the plaintiffs and the defendant are in a competitive relationship. The defendant’s act could result in the plaintiffs losing future revenue from contract fees, given that the value of shogi records would decrease, making it impossible for the plaintiffs to continue their current business model. Third, the game record information used by the defendant was obtained by the plaintiffs’ paywalled streaming, and the defendant’s distribution thereof was an act of free-riding on the costs and efforts invested by the plaintiffs to utilise the game records.

As the defendant used the entirety of the game records on the actual day of the game on which the value of information was at its highest, the defendant’s act significantly interfered with the plaintiff’s business. Moreover, the court found that the defendant had malicious intent to the plaintiffs. The defendant demonstrated an attitude of non-compliance with the guidelines for use of the shogi games records created by the plaintiffs by posting that the collection of fees based on the guidelines constituted extortion and unscrupulous business practices. The defendant also seemed to encourage others to engage in non-compliance with the guidelines through the posts.

Based on the above facts, the court concluded that, the defendant’s act had infringed the plaintiffs’ legally protected interest other than the interest to be enjoyed through the use of works, and, thus, found the existence of the “special circumstances” referred to in the Supreme Court Judgment, given that the act was (i) an act that competed with and caused significant adverse effects on the plaintiffs’ business activities, which they undertook at considerable expense and effort, (ii) an act of free-riding on the results of the plaintiffs’ substantial expense and effort, and (iii) an extremely malicious act that greatly diminished the value of using the shogi game records by utilising all the records on the same day. This matter is still being disputed at the Tokyo High Court as a result of an appeal.

Analysis of the two precedents

As mentioned in the introduction, the Supreme Court Judgment ruled that an act of using a work that does not fall within any of the categories of works under the Copyright Act of Japan does not constitute a general tort unless there are “special circumstances”, such as an infringement on any legally protected interest by the said act other than the interest to be enjoyed through the use of works that are subject to regulation under the Copyright Act. Based on the above two precedents, it can be said that the following were identified as relevant factors for a finding of “special circumstances”:

• (i) the nature of the plaintiff’s profit that was infringed by the defendant;
• (ii) the time, effort, and cost invested by the plaintiff;
• (iii) the contents and extent of disadvantage suffered by the plaintiff;
• (iv) the purpose and manner of the defendant’s use; and
• (v) the defendant’s harmful intention to the plaintiff.

The authors’ analysis of the importance of each factor is as follows.

Regarding factor (i), the plaintiff must demonstrate its legally protected interests other than interests protected by intellectual property law, such as the interest of exclusively using goods or works, based on the Supreme Court Judgment. Notably, in both cases, the plaintiff did not argue that the information used by the defendants was copyrighted work and did not raise an intellectual property claim. If the plaintiff had added an intellectual property claim, and the court had not found the information to be copyrightable, the plaintiff would have faced difficulty proving a general tort claim because it would have had to prove that the interest asserted in the intellectual property claim differs from that asserted in a general tort claim, in accordance with the ruling by the Supreme Court. Considering these circumstances, it might be appropriate for the plaintiff not to raise an intellectual property claim if it is likely to be unable to prove such claim.

Regarding factor (ii), although the amount of invested time, effort, and cost is a basis of establishment of a general tort claim, it is not enough for the courts to affirm such a claim merely because the plaintiff took much time, effort, and cost, since there are some precedents in Japan which presented such ruling.

Regarding factor (iii), both cases mentioned the effect of the defendant’s act on the plaintiff (act of free-riding on information provided by the plaintiff), and were judged from the perspective of the necessity to protect the business profits of the infringed party and the content and extent of disadvantage suffered by the infringing party. The Band Score case pointed out that the incentive for creating band scores through transcription would disappear, leading to a decline in the production of transcribed sheet music and the deterioration of the music publishing industry. The Shogi YouTuber case highlighted that the establishment of business models involving licensing fees for broadcasts, streaming, and game record usage to broadcast/streaming service providers, as well as paid distribution through these providers, would be hindered. It can be said that what both cases have in common is that if the act of free-riding on information were to be left unchecked, the business structure comprising the production and distribution of information would collapse, resulting in the harmful effect of the said type of information ceasing to exist in circulation in the future. Therefore, this factor is considered to be of great importance in determining whether or not a general tort claim can be established.

Regarding factors (iv) and (v), the above cases described the nature of the infringing party’s actions from the perspective of free competition. For example, in the Shogi YouTuber case, the court determined that the defendant, while aware of the competitive relationship among the plaintiffs, obtained real-time game record information and used the entire game record in a video stream on the actual day of the game to obtain revenue. These two factors are also significant, and in particular, the harmful intention in (v) is a big circumstance that supports the finding that the act was committed outside of the scope of free competition, though it is generally not the requirement of a general tort claim.

Conclusion

As mentioned earlier, after the Supreme Court Judgment, almost all of the lower court precedents denied general tort claims in cases not protected by intellectual property law. Under such circumstances, the Band Score case and the Shogi YouTuber case were two cases in which general tort claims were affirmed. One perspective is that the emergence of the two precedents reflects a change in the judgmental tendencies of the courts, and it is possible to predict that similar rulings affirming general tort claims will continue to appear in the future. On the other hand, it is also possible to view these rulings as merely affirming general tort claims because the cases presented facts that warranted such a finding, suggesting no change in the court’s overall tendencies. For example, it could be understood that a general tort claim was affirmed in these cases solely because the infringing party’s conduct in both cases was particularly egregious, for example, by jeopardising the infringed party’s business continuity.

Ultimately, it is difficult to make an immediate determination on whether the court judgment trends have changed solely based on the Band Score case and the Shogi YouTuber case. The number of court rulings affirming the establishment of general tort claims following the Supreme Court Judgment remains limited, and it will be necessary to continue monitoring future trends in court rulings.