On 12 June at 5:21pm ET, Anthropic received an export-control directive ordering it to block any foreign national, inside or outside the US, from using Fable 5 and Mythos 5. Complying meant disabling both models for every customer. All other Claude models stay live.
The government's stated concern, per Anthropic, is a jailbreak that lets Fable find software vulnerabilities. Anthropic says the demonstrated technique surfaced only a few previously known, minor bugs that other public models locate without any bypass. According to the Wall Street Journal, the alarm came from Amazon CEO Andy Jassy, Anthropic's own largest backer, who told Treasury Secretary Scott Bessent that Amazon researchers had used Fable 5 to obtain information that could be used in cyberattacks.
Anthropic is complying while disputing the basis, warning that pulling a model over one narrow jailbreak would, applied evenly, halt new model deployments across the whole industry. The timing stings: it lands just as Anthropic readies a planned IPO.