US Government Tightens Access to Anthropic Mythos 5 and OpenAI GPT‑5.6 AI Models

In June 2026 the U.S. Department of Commerce issued an export‑control order that barred foreign nationals from Anthropic’s most advanced AI models, Mythos 5 and Fable 5, citing national‑security risks. After weeks of negotiations, the government partially lifted the restriction, allowing Mythos 5 to be redeployed to a limited list of U.S. cybersecurity and critical‑infrastructure organizations. Discussions are ongoing about restoring Fable 5, which is intended for broader public use.

At the same time, the White House formally requested that OpenAI curb the public rollout of its new GPT‑5.6 series – Sol, Terra and Luna – limiting preview access to a small group of pre‑approved U.S. partners. OpenAI says the models offer advanced cybersecurity capabilities but must be released under “case‑by‑case” government review to prevent misuse. Both companies have said the temporary restrictions are undesirable but necessary while safety and export‑control frameworks are finalized.

European regulators, including ENISA, have been seeking limited access to Anthropic’s Mythos model, but the U.S. export‑control list remains the decisive factor for any broader deployment.