Anthropic suspends Fable 5 and Mythos 5 AI models after US government directive
Anthropic abruptly shut off access to its most advanced AI models, Fable 5 and Mythos 5, just days after launch, following a US government directive citing national security.
A sudden directive
Anthropic said on Friday it had been ordered by the US government to suspend access for all foreign nationals to its Fable 5 and Mythos 5 artificial intelligence models, citing national security concerns. The directive, issued under export control regulations, came from the Commerce Department, according to Axios. The company stated that it must "abruptly disable Fable 5 and Mythos 5 for all our customers to ensure compliance." Access to other Anthropic models remains unaffected.
The order followed the launch of the two models only three days earlier. Fable 5, a version of the more powerful Mythos 5, had been made available to paying subscribers of Anthropic's Claude service. The company had previously described Fable 5 as its most capable public model, with safeguards to prevent misuse.
The jailbreak claim
Anthropic believes the government acted after learning of a method to bypass, or "jailbreak," Fable 5's safeguards. The company said it had seen evidence only of a "narrow, non-universal jailbreak" that could identify minor software vulnerabilities, and that other publicly available models like GPT-5.5 possess similar capabilities. Anthropic argues the recall is disproportionate.
We disagree that the finding of a narrow potential jailbreak should be cause for recalling a commercial model deployed to hundreds of millions of people. If this standard was applied across the industry, we believe it would essentially halt all new model deployments for all frontier model providers.
The Commerce Department has not publicly detailed specific concerns. An Axios source said the administration wants time "to harden the national security apparatus" against such threats, a process that could take "a few weeks."
A tense relationship
The incident adds to friction between Anthropic and the Trump administration. The two sides are already involved in a lawsuit over an order to stop government agencies from using the company's AI tools. Anthropic CEO Dario Amodei has long advocated for government oversight of AI, including mandatory audits, but insisted such actions should follow a "transparent, fair, clear and technically grounded legal process." The company called Friday's directive a "misunderstanding" that did not meet those principles.
I can't determine whether this is legal harassment or an overzealous security reflex. It's simply grotesque.
Dean Ball, a former White House AI adviser, voiced his bewilderment on social media.
- Anthropic launches Fable 5 and Mythos 5 for subscribers, promoting advanced safeguards against misuse.
- US Commerce Department directs Anthropic to suspend foreign access; Anthropic shuts off both models for all customers.
Global repercussions
The suspension could have long-term consequences for Europe. European companies and governments heavily rely on American AI models. If the most advanced systems become restricted, they risk falling behind, using outdated or less capable technology, with implications for competitiveness, security, and digital autonomy. Anthropic said it is working to restore access as soon as possible.
