Anthropic shuts down Fable, Mythos models following Trump admin directive

Anthropic announced the immediate shutdown of its recently launched Fable 5 and Mythos 5 AI models. This came after receiving a directive from the US Commerce Department, which subjected the models to export controls, restricting their use to within the United States. Anthropic stated that abruptly disabling access for all customers was the only way to ensure immediate compliance. Other Anthropic models remain unaffected.

Concerns from the Trump administration reportedly stemmed from a "jailbreak" that bypassed safeguards designed to block prompts related to cybersecurity, chemistry, and biology in Fable 5. The administration requested a pause in the models' release to allow national security measures to be strengthened against such threats, a process expected to take "a few weeks."

Anthropic, however, indicated that the government provided only "verbal evidence of a potential narrow, non-universal jailbreak." The company described the alleged jailbreak as capable of finding only "minor" software vulnerabilities, similar to capabilities in other publicly available models like GPT-5.5.

While complying with the directive, Anthropic expressed disagreement with the government's action. The company argued that a narrow potential jailbreak should not warrant recalling a commercial model deployed to millions, suggesting that such a standard would hinder future AI model deployments across the industry.

This incident follows President Trump's executive order earlier in the month, which encouraged AI model developers to undergo voluntary government security testing.