Anthropic disables its most powerful AI models worldwide after US government order
Anthropic has disabled its two most advanced AI models, Fable 5 and Mythos 5, for all users worldwide.
Anthropic has disabled its two most advanced AI models, Fable 5 and Mythos 5, for all users worldwide.
The AI giant shut down the models after the US government issued an export control directive citing national security authorities.
The company said the directive, received at 5:21pm ET on Friday, ordered it to suspend all access to both models by any foreign national, whether inside or outside the United States, including Anthropic’s own foreign national employees.
In a statement on its website, Anthropic said the order is so broad that the only way to comply is to disable both models entirely for every customer, regardless of nationality. Access to all other Anthropic models remains unaffected.
Anthropic said it reviewed a demonstration of the technique the government cited and found it could only find a small number of previously known, minor vulnerabilities.
It said these issues are simple enough that other publicly available models, including OpenAI’s GPT-5.5, can identify them without requiring any bypass, and which security defenders use every day to find and fix software flaws.
The company also insisted that has implemented robust safeguards designed to significantly limit the risk of Fable being misused
Anthropic said it disagrees that the discovery of a narrow, non-universal jailbreak should be grounds for recalling a commercial model already deployed to hundreds of millions of users.
The company warned that if this standard were applied across the industry, it would effectively halt new model deployments for every frontier AI developer.
The company said it supports the government having the ability to block unsafe AI deployments, but only as part of a statutory process that is transparent, fair, clear, and grounded in technical facts, and said this directive does not meet that standard. The company also said it is working to return online.
Anthropic said that in the weeks leading up to Fable 5’s launch, it worked with the US government, the UK’s AI Security Institute, multiple private third-party organisations, and internal teams to red-team the model’s safeguards for thousands of hours.
Those tests, the company said, showed Fable 5’s protections were substantially more effective than any previously deployed model, and no tester found a “universal jailbreak” capable of broadly unlocking the model’s restricted cyber capabilities.
Nairametrics had earlier reported that Anthropic called on developers of advanced AI systems to establish a coordinated and verifiable framework for slowing or temporarily pausing AI development if future models begin improving themselves faster than society can effectively manage the associated risks.
The company made the appeal in a detailed post published on its website, warning that increasingly capable AI systems could eventually reach a point where humans lose meaningful oversight and control.
Anthropic argued that the industry should agree in advance on clear conditions and mechanisms for halting development if such risks begin to materialize.
