WHY THIS MATTERS
Three days after launch, the US government ordered Anthropic to suspend foreign nationals' access to the Fable 5 and Mythos 5 models, citing national security.In this article
The order
On Friday, June 12, 2026, Anthropic received an export-control directive from the US government ordering the suspension of all access to the Fable 5 and Mythos 5 models by any foreign national, inside or outside the US — including Anthropic's own foreign employees.
The stated reason
According to news reports, the government believed a method had been found to bypass ("jailbreak") Fable 5's safeguards, potentially turning the model into an unrestricted cyber tool.
Anthropic's response
Anthropic complied with the order but publicly disputed the stated reason, arguing the cited vulnerability is simple and already reproducible in other publicly available models, such as GPT-5.5.