Approximately 350 protesters rallied at the headquarters of OpenAI before marching on the offices of Google DeepMind and Anthropic on Saturday in what became the largest demonstration against the development of AI in American history. The peaceful demonstration, dubbed “The AI Protest,” saw no confrontation with police as the San Francisco Police Department cleared streets for the marching crowd. Organized by a coalition including Stop The AI Race, QuitGPT, AI Action, PauseAI, Evitable and Stop AI, the protest centered on concerns that unrestricted development by “frontier labs” may result in artificial superintelligence, or ASI. “AI poses an existential threat to humanity; it will only get smarter and almost certainly more powerful than us,” said Stop The AI Race founder Michaёl Trazzi, a former AI researcher who embarked on a hunger strike in September 2025 outside Google’s DeepMind office. The protest commenced at noon outside OpenAI headquarters, with marchers snaking up by Oracle Park and descending on downtown San Francisco to rally outside Anthropic and Google DeepMind. Organizers handed out free slushies and a brass band marched as attendees called for a moratorium on AI development.