Author: Attorney/Patent Attorney Masatoshi Tanaka

1. Growing Need for Protection of “Voice” Rights

The emergence of generative AI has made it possible to “train” AI with a specific person’s voice allowing it to “speak” or “sing” any words with the voice or tone as if it were that specific person itself. This is something that generative AI is good at and can easily do.

In reality, platforms like YouTube and TikTok, feature numerous contents called “AI covers” in which unrelated songs are sung in the voice of anime characters or popular singers. The Japan Actors Union, which represents voice actors, conducted a survey on the unauthorized use of “voices” from December 2023 to February 2024. The survey revealed that the voices of 267 voice actors had been used without authorization.

For voice actors, their “voice” is both the product and an expression of their artistic talent. Therefore, such unauthorized use not only has a significant economic impact but also damages the reputation of their “voice”, which may potentially cause a serious problem.

In response to this situation, the Japan Actors Union issued a proposal titled “Proposal on the Utilization of Generative AI Technology“, on June 13, 2023, expressing their concern regarding the unrestricted use of generative AI using voices and calling for the establishment of “voice portrait rights”.

2. Is “Voice” Legally Protected Under the Current Legal Systems?

(1) Protection Under Publicity Rights

Publicity rights are the rights to exclusively use an individual’s name, likeness, etc. when such attributes have the ability to attract customers and promote the sales of products, etc. (Supreme Court Judgment, February 2, 2012, Civil Case Collection Vol. 66, No. 2, p. 89 (Pink Lady case)). The establishment of such publicity rights for the names and likenesses of celebrities is a well-established legal theory based on judicial precedent.

However, since the requirements for publicity rights are not clearly defined in statutory law, their boundaries are ambiguous, and at present, it is unclear whether “voice” is directly protected by publicity rights (although it is possible that future judicial precedent may clarify that “voice” is included in publicity rights).

(2) Protection Under the Unfair Competition Prevention Act

The Unfair Competition Prevention Act prohibits “using an indication of goods or business (meaning a name, trade name, trademark, marks, containers or packaging for goods belonging to a person’s business, or any other indication of a person’s goods or business; the same applies hereinafter) that is identical or similar to another person’s indication of goods or business that is widely-recognized among consumers as belonging to that person” (Unfair Competition Prevention Act, Article 2, paragraph 1, item (i)).

Whether “voice” falls under the category of these “indications of goods or business” is currently unclear. However, in responding to questions in the Diet on April 15, 2024, the Ministry of Economy, Trade and Industry stated that they “would like to consider the review of the Unfair Competition Prevention Act as necessary“, indicating a potential for future legal protection under the Unfair Competition Prevention Act.

(3) Conclusion

As mentioned above, regarding “voice” rights, protection under publicity rights or the Unfair Competition Prevention Act is currently only a “possibility”, and therefore, the situation does not allow for a definitive statement that “legal protection exists”. It is necessary to closely monitor future developments in judicial precedents, guidelines, legislation, etc.

3. In the United States, Certain Legal Protections Apply to “Voice”

In California, “voice” rights have a certain degree of protection under both statutory law and common law.

Specifically, Section 3344 of the California Civil Code stipulates that an individual’s name, signature, photograph, likeness, and “actual voice” are protected. However, this provision only protects the “actual voice” and not the tone of the voice, and therefore the unauthorized use of an “AI-generated voice similar to the person” does not necessarily directly violate the statute. Nevertheless, the fact that “voice” is afforded a certain degree of protection is noteworthy.

Furthermore, under common law, “voice” is also considered to be protected. A well-known judicial precedent in this regard is Midler v. Ford Motor Co. Singer Bette Midler filed a lawsuit claiming that an imitation of her voice was used in an advertisement without authorization, and the court recognized the infringement of her publicity rights. In this case, the issue was not the actual voice itself, but the imitation of her unique singing style being used for commercial purposes.

Additionally, in the case of Tom Waits v. Frito-Lay, Inc., singer Tom Waits, known for his distinctive voice, filed a lawsuit against Frito-Lay for using a song in their advertisement that imitated his voice. The court ruled that, as a common rule, the infringement of publicity rights is established when a voice is (1) distinctive, (2) widely known, and (3) intentionally imitated for commercial purposes, and ordered Frito-Lay, Inc. to pay damages.

Therefore, in California, certain legal rights regarding “voice” are protected and legal action can be taken against unauthorized commercial use. However, these protections are not unrestricted and are subject to appropriate restrictions in consideration of other rights such as freedom of expression and copyright.

4. Future Protection of “Voice” Rights

As mentioned above, at present in Japan, it is unclear whether “voice” will be legally protected, but this does not mean that “voice” is not protected under the current legal system. In the future, there is a possibility that protection under publicity rights or the Unfair Competition Prevention Act may be recognized depending on individual cases.

Furthermore, while infringement of rights through “imitation” has been a problem, as seen in the California cases mentioned above, generative AI will likely lead to a much larger scale of “voice rights infringement” cases in the future, and such cases may have likely already occurred. It is difficult to justify legal protections for such unrestricted “imitations”, especially when the necessity to protect “voice” rights is increasing.

In the future, it is expected that certain legal protections will be provided to “voice” rights through legal interpretation, formulation of guidelines, new legislation, etc.

In my opinion, an appealing “voice”, like other forms of expression, should be protected as a cultural asset of humanity. There is an urgent need to establish a legal framework for the protection of “voice” rights before it is too late.