US government lifts restrictions on Anthropic’s Mythos 5

On Friday, the US government authorized Anthropic to release Claude Mythos 5 to over 100 organizations, including major corporations and government agencies. The authorization was formalized in a letter from Secretary of Commerce Howard Lutnick to Anthropic Chief Compute Officer Tom Brown.

Export licenses and domestic transfer restrictions no longer apply to organizations listed in Annex A or to Anthropic’s foreign national employees.

Two weeks ago, the administration imposed export controls on Mythos following warnings from Amazon regarding potential model jailbreaks. This move halted both Mythos and the smaller Fable 5. The letter does not mention Fable 5, though sources indicate progress toward its release without a specific timeline.

On the same day, OpenAI released GPT-5.6 to a restricted list of government-approved partners.