The US Government Banned Anthropic's Fable 5 AI. I Tried It Before It Disappeared

On June 12, 2026, the US government issued an export-control directive forcing Anthropic to suspend all access to Fable 5 and Mythos 5 by foreign nationals. Anthropic quickly cut off access pending clarification, arguing safeguards prevent misuse, and suggesting the ban followed a jailbreak demonstration that is neither new nor significant. The company notes that other publicly available models, including GPT-5.5, can reveal similar vulnerabilities. Nearly 150 cybersecurity experts co-signed an open letter to Commerce Secretary Howard Lutnick and national cyber director Sean Cairncross, urging reconsideration and arguing the ban benefits criminals. The letter, sent to the White House, warns that Fable bans could hinder defenders as open-weight models near Mythos-level capabilities.