The US government directed Anthropic to immediately suspend access to its Fable 5 and Mythos 5 AI models on Friday. The company complied with a full global shutdown after receiving the national security order at 5:21 p.m. ET.
The directive requires suspension for all foreign nationals inside and outside the United States. It marks the first recall of a widely deployed commercial frontier AI model.
Anthropic reviewed the cited jailbreak and described it as narrow. The company said the technique involves identifying previously known minor vulnerabilities already detectable by models such as OpenAI's GPT-5.5 without any bypass.
Traders reacted swiftly. The Anthropic perpetual contract on Hyperliquid fell 3.7 percent to around $1,627 on Saturday. Decentralized AI tokens including Bittensor's TAO rose as much as 13.4 percent.
Anthropic stated it will release further technical details within 24 hours and argued that a zero-exploit standard would halt frontier model development across the industry.