The US government lifted its export block on Anthropic's Claude Mythos 5 on Friday, clearing the model for release to more than 100 US institutions including major companies and government agencies. Commerce Secretary Howard Lutnick determined that appropriate safeguards are in place to permit trusted partners to access the model, according to a letter sent to Anthropic compute chief Tom Brown. The decision reverses a two-week standoff between the Trump administration and Anthropic that had forced both Mythos 5 and its consumer counterpart Fable 5 offline after Amazon raised concerns about jailbreak risks.
Commerce Secretary Clears Claude Mythos 5 for Named Institutions
Commerce Secretary Howard Lutnick set out the decision in a Friday letter to Anthropic compute chief Tom Brown. A license is no longer required to export Mythos 5 to the entities named in Annex A. "I have determined that appropriate safeguards are in place to permit certain trusted partners to access the Claude Mythos 5 Model," Lutnick stated, according to Semafor.
Senior Anthropic staff had flown to Washington to meet administration officials during the dispute, according to CNBC. The reversal frees the model behind the Mythos and Fable rollout from controls imposed this month. The block had forced both models offline after Amazon, one of Anthropic's largest investors, raised the alarm. Its researchers had warned that Fable 5 could be jailbroken for harmful use.
Until then, Mythos sat inside Project Glasswing, a vulnerability-hunting program spanning about 150 organizations across more than 15 countries. The model had earlier found flaws in classified systems within hours of government testing.
Executive Order Establishes Voluntary Federal Review Channel
Fable 5 remains offline as sources near the talks said a release is advancing, though the timeline stays unclear. Unlike Mythos, Fable 5 had been open to anyone with a subscription. It briefly stood as the most powerful AI tool available to the public.
A June 2 executive order set up a voluntary channel for federal review of frontier models. Developers can submit models for a cyber check up to 30 days before release. Washington has spent the past year tightening AI chip exports to China. Extending that authority to a model's access marks a new front.
OpenAI followed the same path on Friday. It limited its most powerful GPT-5.6 tier, Sol, to about 20 government-approved partners. The weaker Terra and Luna versions went to the public.
The block first grew from fears over Chinese access. Reporting tied the concern to SK Telecom, a South Korean carrier added to Glasswing in early June before losing access. SK Telecom has denied any China ties.
Dozens of cybersecurity leaders had pressed the administration to drop the controls. The open letter, organized by former Facebook security chief Alex Stamos, drew signatures from firms including Nvidia, Adobe, and Zoom.
FAQ
What did the US government do with Claude Mythos 5 on Friday?
The US government lifted its export block on Anthropic's Claude Mythos 5 on Friday, clearing the model for release to more than 100 US institutions including major companies and government agencies. Commerce Secretary Howard Lutnick sent a letter to Anthropic compute chief Tom Brown stating that appropriate safeguards are in place to permit trusted partners to access the model without a license.
Why was Claude Mythos 5 blocked before this decision?
The block was imposed this month after Amazon, one of Anthropic's largest investors, raised concerns that Fable 5 could be jailbroken for harmful use. The controls forced both Mythos 5 and Fable 5 offline during a two-week standoff between the Trump administration and Anthropic. Reporting tied the concern to fears over Chinese access, specifically related to SK Telecom's involvement in Project Glasswing.
What is the status of Fable 5 compared to Mythos 5?
Fable 5 remains offline while Mythos 5 has been cleared for release to named institutions. Sources near the talks said a Fable 5 release is advancing, though the timeline stays unclear. Unlike Mythos 5, which was restricted to Project Glasswing participants, Fable 5 had been open to anyone with a subscription before the block.
