A class-action antitrust lawsuit was filed on September 18, 2026, in the Northern District of California against Anthropic, OpenAI, Google, and xAI. The plaintiffs, who are users of paid AI services, allege that these companies coordinated to deliberately slow down the advancement of artificial intelligence models.
The legal complaint, filed by the firm Trial Lawyers for Justice, claims that this coordination restricts competition in product development, technological innovation, and investment. The plaintiffs argue that such actions violate US antitrust laws by limiting the quality and capabilities of competing AI products.
The core of the accusation relies on public statements made by industry leaders. On September 12, 2026, Anthropic CEO Dario Amodei proposed slowing down the development of powerful AI systems to improve safety and control. This stance was subsequently supported by OpenAI CEO Sam Altman, xAI founder Elon Musk, and Google DeepMind co-founder Demis Hassabis.
The plaintiffs interpret these sequential public endorsements as evidence of a formal agreement between competitors. However, legal experts note that public calls for caution do not inherently prove a binding legal pact. OpenAI had previously investigated the potential antitrust implications of such industry-wide coordination.
