"Anthropic said on Friday it will 'abruptly disable' its most advanced AI models for all users,"
reports Reuters, "after the U.S. government ordered it to suspend access to the models for foreign nationals, citing national security concerns. The company received the export control directive to suspend access to Fable 5 and Mythos 5 for all foreign nationals, without being given specific details of its national security concern, Anthropic said in a statement."


Anthropic's blog post writes that the directive applies to foreign nationals "whether inside or outside the United States, including foreign national Anthropic employees. The net effect of this order is that we must abruptly disable Fable 5 and Mythos 5 for all our customers to ensure compliance."
"Access to all other Anthropic models will not be affected."

We received the directive from the government today at 5:21pm (ET)... Our understanding is that the government believes it has become aware of a method of bypassing, or "jailbreaking" Fable 5... We have not even received a disclosure of a concerning non-universal potential jailbreak that led to a harmful result. The potential jailbreaks that have been disclosed to us are either entirely benign responses or are minor findings that provide no Mythos-specific uplift.

To date, the government has only given us verbal evidence of a potential narrow, non-universal jailbreak, which essentially consists of asking the model to read a specific codebase and fix any software flaws. Our understanding is that one potential jailbreak was shared with the government. We have reviewed a report that we believe is the basis of the government's directive and validated that the level of capability displayed there is widely available from other models (including OpenAI's GPT-5.5), and is used every day by the defenders who keep systems safe... We are complying with the government's legal directive and are removing access to Fable 5 and Mythos 5 for all users. However, 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.

As we have stated publicly, we believe the government should have the ability to block unsafe deployments, as part of a statutory process that is transparent, fair, clear, and grounded in technical facts. This action does not adhere to those principles. We apologize for this disruption to our customers. We believe this is a misunderstanding and are working to restore access as soon as possible.

Reuters notes that Amazon's cloud unit AWS "said late on Friday that Anthropic has asked it to revoke access to the models for 'all users in all regions.'"

Dean Ball, a former White House official who contributed to the AI Action Plan the administration issued in the summer of 2025, said in a post on X that the order suggests all "non-Americans" would be restricted from using Anthropic's latest models, including those based in the U.S. "This means you should expect to have to prove your citizenship to use Anthropic models," Ball said.
Several key Anthropic personnel, including co-founder Chris Olah, AI researcher Andrej Karpathy and philosopher Amanda Askell, were born outside the United States.

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