Tokyo court extends publicity rights to the voice in Kenjiro Tsuda's AI clone suit against TikTok

What the user actually built was a persona. The narration had a delivery Tsuda described as unmistakably deep and "lustrous" ^[12], and the profile picture resembled a Jujutsu Kaisen character he voices ^[9]. The account kept it up for about 15 months ^[15], roughly a dozen videos a month ^[16]. His lawyers said it gained traction only because a popular actor's voice was narrating ^[8].

TikTok described the same videos the way platforms like to picture their users' choices. It argued in court that the narration was a "generic male voice" and that any similarity to Tsuda was subjective, according to court records AFP reviewed ^[7].

The court's test looks at how a voice is used. AFP believes this is Japan's first lawsuit defending a person's vocal identity against AI copies ^[4]. In it, the Tokyo district court found that publicity rights cover a voice used purely for its commercial appeal ^[2]. Takahashi compared a voice to a portrait, as a symbol of personality ^[2]. "The unauthorised use of a performer's voice ... can be considered an infringement on publicity rights," Takahashi said ^[1].

The ruling matters most to the product managers who run voice libraries and clone features, and to the trust teams at platforms that host what users make with them. Making a clone takes very little audio. Google's latest Gemini text-to-speech models can clone a voice from 30 seconds of audio ^[14].

Tsuda got the principle and not much else. His lawyer, Takashi Hirano, told reporters the ruling "ended up making both sides look victorious" ^[13]. The reports do not say whether the court awarded damages. The judge's "can be considered" wording ^[1] gives later courts room to narrow the finding, and TikTok said it would study the judgment before deciding its next steps ^[10].

If I were shipping synthetic narration in Japan, I'd require consent and a license for any voice a listener could put a name to whenever the output makes money. That goes further than one district court's wording ^[2]. It costs slower launches and license fees. The alternative is defending a "generic" label after the videos are up, which is where TikTok ended up ^[7].

Two axes sort a voice catalog. One is whether an ordinary listener could name the person. The other is whether the output earns money from that recognition. Voices nobody could name ship in either case, with a record of how each was built. Nameable voices in unpaid, personal use fall outside the commercial-appeal test as AFP reported it ^[2], and on this evidence that corner carries less risk. Put a nameable voice in paid output and it needs consent and a license before launch. I'd count the packaging toward recognition. A character avatar beside a sound-alike narrator puts a voice in the named column, and this account used exactly that pairing ^[9].