U.S. lifts block on Anthropic's Mythos 5 for trusted partners

Commerce Secretary Howard Lutnick wrote Friday that “appropriate safeguards” were in place, lifting Washington’s block on Anthropic’s Mythos 5 and allowing the model to reach about 100 companies and federal agencies that the Commerce Department now treats as trusted partners. The approval extends to foreign national employees of those entities and to Anthropic’s foreign national employees. The letter did not restore access to Fable 5, leaving Anthropic’s most powerful models under different rules.

The reversal followed a June 12 directive that reached Anthropic at 5:21 p.m. ET and ordered the company to suspend access to Fable 5 and Mythos 5 for any foreign national, whether inside or outside the United States. It disabled both models globally to comply, and the government cited national security authorities and believed it had found a “jailbreak” path into Fable 5. The company had already spent thousands of hours with U.S. and U.K. government red-teamers and private testers before launch and had not seen a universal jailbreak.

President Donald Trump ordered federal agencies on February 27, 2026, to stop using Anthropic technology, and Defense Secretary Pete Hegseth moved to designate Anthropic a “Supply-Chain Risk to National Security.” In June 2024, Anthropic was the first AI company to deploy frontier models in classified U.S. government networks, and in July 2025 the Defense Department awarded up to $200 million each to Anthropic, Google, OpenAI and xAI to speed adoption of advanced AI.

OpenAI has also limited the initial rollout of a new model to a small group of government-approved or trusted partners. Mythos 5 can return to vetted users, but Fable 5 remains outside the gate.