Subscribers sue over a promise to slow AI: defendants hold 80% of paid subscriptions in the US

That same day, Sam Altman, Elon Musk, and Demis Hassabis publicly endorsed the essay. Four subscribers saw this as an agreement on pace. They estimate that the four companies account for at least 80% of the US market for paid consumer AI subscriptions.

What they seek. The lawsuit was filed on 18.09.2026 in the US District Court for the Northern District of California under Section 1 of the Sherman Antitrust Act. The class includes US residents who have bought a paid individual subscription to ChatGPT, Claude, Grok, or Gemini since 12.09.2026. The plaintiffs seek treble damages, an injunction against agreements on the pace of AI development, and a jury trial.

Amodei's plan itself has three steps and proposes that the industry slow down by an "extra year or two." Anthropic would take the first step unilaterally: a team of external evaluators would work inside the company with employee-level access, office space, and the right to publish its findings without Anthropic's approval.

Public evidence only. The complaint contains neither leaks nor internal correspondence. Amodei wrote that coordination would require an antitrust exemption, Altman replied that OpenAI would not wait for such an exemption, and OpenAI's Chris Lehane confirmed that the company had already been working with Anthropic and Google DeepMind for several weeks.

The complaint describes the subject of the alleged collusion specifically: limiting computing resources and the use of AI to improve AI. The plaintiffs do not challenge any company's right to slow down on its own; they call only the shortcut of a joint agreement unlawful.

None of the four companies had commented on the lawsuit as of 19.09.2026.