OpenAI has been sued in a class action in the United States over allegations it shared ChatGPT user data with Meta and Google.

According to blockchain outlet BeInCrypto on May 14 local time, the lawsuit filed in a U.S. federal court in California claims OpenAI embedded tracking technology on the ChatGPT website without consumer consent and transmitted personal information to outside parties.

The lawsuit covers U.S. residents who entered questions on ChatGPT.com. Plaintiffs claim OpenAI passed personal questions and account-related information to Meta and Google, and that the companies' advertising networks reach billions of people daily. OpenAI is the only named defendant, but Meta and Google are also cited as recipients of the data.

At issue is analytics and ad-targeting tracking technology that Meta and Google provide to website operators. Plaintiffs believe OpenAI inserted the code into the ChatGPT site to automatically transmit user information. They claim the transmitted data included query topics, account identifiers and email addresses linked to individual users.

Plaintiffs stressed that users reasonably expected a certain level of privacy protection when using the chatbot. They pointed out that sensitive questions related to finance, healthcare and law are often entered into ChatGPT. They also cited a Cyberhaven report estimating that about 1 percent of the data employees paste into ChatGPT is confidential. The figure refers to leaked internal corporate material, but plaintiffs claim the same concern applies to individual users seeking health, money or legal advice.

Plaintiffs sought monetary damages and an injunction to stop the practice. The complaint also said whether the court accepts the plaintiffs' arguments depends on how it interprets the level of privacy protection users expect from AI services. It also raised as an issue how much information OpenAI disclosed during the sign-up process.

The lawsuit also intersects with existing privacy disputes involving OpenAI. In 2023, a class action was filed alleging the use of personal data for model training. Japan's privacy regulator and the European non-governmental organisation NOYB have also continued to raise issues related to the General Data Protection Regulation, or GDPR.

Earlier this year, Perplexity AI was also sued separately over allegations of similar conduct involving the use of Meta and Google trackers. That suggests pixel-based monitoring in consumer AI services has emerged as a new privacy litigation issue. Google has also faced a lawsuit over allegations it improperly used personal data for AI training.

Timing could also be a burden for OpenAI. OpenAI is reportedly preparing an initial public offering, and claims have also been raised that it fell short of this year's revenue and user targets. A prolonged class action could become a variable in that process. The complaint also mentioned the possibility of additional scrutiny in markets where data protection rules are stricter than in the United States.

No hearing schedule has yet been set, and OpenAI has not issued a public position on the filing of the lawsuit.