Trump Forces Anthropic to Shut Down Fable 5 and Mythos 5 Globally

In an unprecedented move, the Trump administration has ordered Anthropic to immediately shut off access to its two most powerful AI models, Fable 5 and Mythos 5, for every user on the planet. The directive, delivered by Commerce Secretary Howard Lutnick to Anthropic CEO Dario Amodei, invokes national security export control authorities to block any foreign national from accessing the models, whether they are inside or outside the United States. Because Anthropic cannot technically segregate its user base that cleanly, the practical result is a full global shutdown of both models.

Anthropic says it received the letter at 5:21pm ET and is complying, while publicly pushing back hard on the reasoning behind it.

The Jailbreak That Triggered a Shutdown

The government's stated concern is a reported method for bypassing, or "jailbreaking," Fable 5. A jailbreak, in this context, means a technique that tricks a model into ignoring its built-in safety guardrails. An administration official told Axios the Commerce Department decided to take the action after another company claimed it was able to jailbreak Mythos, alarming the administration about possible national security risks.

Anthropic reviewed the reported technique and says the threat is being dramatically overstated. Anthropic's understanding is that the government believes it has become aware of a method of bypassing Fable 5, but when Anthropic reviewed a demonstration of the technique, it found a small number of previously known, minor vulnerabilities that other publicly-available models can also discover. In its statement, Anthropic pointed directly at OpenAI as a comparison: the level of capability displayed is widely available from other models, including OpenAI's GPT-5.5, and is used every day by the defenders who keep systems safe.

Anthropic also drew a clear technical distinction between what was found and what would actually be dangerous. A universal jailbreak is a technique that broadly disables a model's safety filters across all topics. A non-universal jailbreak only works in narrow, specific contexts. Anthropic says it has not received a disclosure of a concerning non-universal potential jailbreak that led to a harmful result, and that the potential jailbreaks disclosed are either entirely benign responses or minor findings that provide no Mythos-specific uplift.