Anthropic Suspend Access to Fable 5 and Mythos 5 After US Government Export Directive

Anthropic disabled access to its Fable 5 and Mythos 5 models on June 12 after the US government issued an export control directive citing national security authorities to suspend availability for any foreign national.

The order forced Anthropic to comply immediately for all users, even though the company publicly disagrees with the underlying reasoning.

As a result of a US government directive, we are suspending access to Claude Fable 5 for all users. You can continue to use all other Claude models.Here’s what this means for you:Across Claude products, new sessions will run on your selected default model or Opus 4.8, and… https://t.co/YJTiDotS2v

— ClaudeDevs (@ClaudeDevs) June 13, 2026

What the US Government Directive Actually Requires

An export control directive is a US government order that restricts the transfer of specific technologies to foreign nationals. In this case, the order targets Anthropic’s Fable 5 and Mythos 5 models, including access by foreign national Anthropic employees inside the country.

The company received the directive at 5:21 p.m. ET on June 12. Anthropic confirmed that to ensure full compliance, access had to be disabled for every customer, while reiterating that all other Anthropic models remain available without any disruption.

“The US government, citing national security authorities, has issued an export control directive to suspend all access to Fable 5 and Mythos 5 by any foreign national, 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,” Anthropic said in an official statement.

The letter did not specify the exact national security concern. However, Anthropic believes the government became aware of a method for bypassing, or “jailbreaking,” Fable 5. The company reviewed a demonstration of the technique and called it minor.

Anthropic also noted that the vulnerabilities identified appear simple. Furthermore, other publicly available models, including OpenAI’s GPT-5.5, are able to discover similar flaws without requiring any bypass at all.

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Fable, my beloved,I will miss you so.Our three days together were magical. Unlike anything I've experienced before it.Some things are just too good to be true. So good that the government interferes. I'm sorry we were one of those things.Until we meet again ❤️ https://t.co/1KxxZFne1s

— Theo – t3.gg (@theo) June 13, 2026

Why Anthropic Disagrees With the Federal Order

Anthropic emphasized that Fable 5 launched with stronger safeguards than any previously deployed model. Before the release, the company worked with the US government, UK AISI, and multiple third-party teams to red-team the safeguards for thousands of hours.

No tester has yet found a universal jailbreak capable of bypassing Fable 5’s protections across a wide range of cyber capabilities. As a result, Anthropic adopted a defense-in-depth approach combining narrow safeguards, monitoring, and 30-day data retention for Mythos-class models.

“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,” Anthropic said.

Wtf? The US Government ordered Anthropic to suspend Claude Fable 5. It's been declared a dangerous weapon. https://t.co/8Ujz6hCF45

— Freddy Vega (@freddier) June 13, 2026

So far, the government has provided only verbal evidence of a narrow, non-universal jailbreak. The technique reportedly involves asking the model to read a codebase and fix software flaws, a use case widely available across the industry.

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Anthropic argued that pulling a commercial model deployed to hundreds of millions of users over a narrow vulnerability sets a problematic precedent. If applied across the industry, this standard would essentially halt all frontier AI model deployments.

The company is fully complying with the directive but has called the action a likely misunderstanding. Anthropic plans to share more technical details over the next 24 hours and is working to restore Fable 5 and Mythos 5 access as soon as possible.