Amodei wrote that coordinating on pace would need an antitrust waiver. Altman said OpenAI would not wait for one. Both lines are now in a lawsuit.

Four consumers filed a class action in the Northern District of California on 18 September, alleging that Anthropic, OpenAI, SpaceXAI, and Google entered a horizontal agreement to slow AI development, violating the Sherman Act. The complaint claims the companies publicly proposed, accepted, and confirmed limits on training compute, training runs, and capability checkpoints. Plaintiffs seek treble damages, an injunction, and a jury trial. They argue the coordination was intentional and that no antitrust waiver or exemption applies, while OpenAI’s policy chief confirmed prior collaboration with Anthropic and Google DeepMind.