Stop AI is an American activist organization formed in 2024. Based in Oakland, California, it seeks to ban the development of artificial general intelligence, a hypothetical technology being researched by some companies, including OpenAI.
Some Stop AI members have been arrested for blocking doors to OpenAI offices as protest. According to a Stop AI leader, in late 2025, Stop AI co-founder Sam Kirchner punched him due to disagreement about the organization and suddenly disappeared. OpenAI and local police feared potentially violent intentions and locked down San Francisco offices. Kirchner was expelled from Stop AI.