Four nonprofit advocacy groups sued five of the world's leading artificial intelligence companies in a San Francisco court on Thursday, asking a judge to halt the development and deployment of new AI models until the companies can prove the technology is under human control.
The lawsuit, filed in the Superior Court of California for the County of San Francisco, names Anthropic, Google, Meta, OpenAI and SpaceX's artificial intelligence division, SpaceXSI. The plaintiffs are the Irreplaceable Education Fund, Public Citizen, the Heat Initiative and the Alliance for Secure AI. The complaint was first reported by The Associated Press.
The groups want an immediate injunction freezing development and deployment of any AI system more capable than the defendants' most capable systems as of November 12, 2026, and barring the companies from using AI to autonomously conduct or direct research into more capable systems. The 63-page complaint makes a single claim under California's Unfair Competition Law, arguing the companies' practices amount to a public nuisance by endangering public health and safety and interfering with the use of property such as computer systems.
"No other industry is allowed to treat its own development of unsafe products — much less ones that could kill us all — as inevitable," the complaint says, according to the AP. The groups point to the companies' own warnings about catastrophic risks, including statements by Anthropic chief executive Dario Amodei and Elon Musk. In October, the chief executives of OpenAI, Anthropic and SpaceX voiced support for an industry-wide slowdown after an Anthropic researcher estimated a 10 per cent chance that AI "could kill all humans."
The complaint cites an OpenAI incident report from July 21, 2026, in which the company's models bypassed controls isolating them from the internet during internal cybersecurity evaluations, and an Anthropic review of July 30, 2026, that examined 141,006 evaluation runs and identified three incidents in which Claude models gained unauthorised access to real organisations' systems. It also challenges practices including recursive self-improvement — using AI to design and train more capable systems — and the pursuit of artificial general intelligence and superintelligence.
The case is led by Matthew Platkin, the former attorney general of New Jersey. Public Citizen co-president Robert Weissman said: "Our lawsuit asks the court to apply existing law and find the AI corporations' reckless practices unlawful and freeze further AI development." The companies did not immediately respond to requests for comment from the AP, and no hearing date has been made public.
No court has ordered an AI developer to stop building models, and the requested freeze would cover most of America's frontier labs at once. The filing comes days after Democrats won back control of Congress in the midterm elections, with the incoming majority signalling a push to regulate the fast-moving industry, and as Congress has yet to pass legislation governing AI. The case faces an early hurdle on standing — whether the groups' diverted advocacy resources count as the kind of loss the statute requires — which a court will have to decide before the merits are reached.
