Anthropic, OpenAI, SpaceXAI and Google face a lawsuit filed Friday in the U.S. District Court for the Northern District of California, alleging that the companies violated antitrust laws by coordinating to slow AI development. Four named plaintiffs who pay for ChatGPT, Claude, Grok or Gemini argue that the alleged agreement reduced the value of their subscriptions and seek to represent a nationwide class of other paid users. The complaint centers on Sept. 12, when Anthropic CEO Dario Amodei called for industrywide cooperation to decelerate AI advances in favor of stronger safety measures. The lawsuit says OpenAI's Sam Altman, SpaceXAI's Elon Musk and Google DeepMind's Demis Hassabis publicly supported Amodei's proposal that day. Amodei acknowledged potential antitrust concerns and suggested U.S. government mediation or a narrow waiver for certain safety discussions, while Altman said OpenAI supported consistent federal safety requirements without waiting for an antitrust exemption. President Donald Trump rejected calls to limit AI development and said Saturday that he was forming an AI task force and would appoint an AI czar. Sen. Josh Hawley said he would not support an antitrust exemption allowing major technology companies to collaborate.