Four nonprofit organizations have sued OpenAI, Anthropic, Google, Meta, and SpaceX, seeking an immediate ban on developing or deploying more powerful AI systems. The lawsuit was filed Thursday in San Francisco Superior Court and asks that each company’s models be limited to the capabilities of its most advanced models as of November 12, 2026. The plaintiffs also want to ban autonomous AI research aimed at improving models. The groups argue that existing California law is sufficient to address development activities that could allegedly cause catastrophic harm. The defendants have not been found legally liable, and warnings about potential catastrophes alone do not prove a violation of California law.