Anthropic Restores Claude Fable 5 After US Export Controls Lift

Anthropic redeployed Claude Fable 5, its most capable generally available model, on July 1, 2026, after US export controls were lifted. These controls, which had also affected Claude Mythos 5, were put in place on June 12, 2026, following a directive from the US government that restricted the models to non-foreign-nationals. Anthropic suspended both models for all users because it could not verify nationality in real time, a move intended to prevent non-compliance with the directive.

The trigger for the export controls was a report from Amazon researchers detailing a method to bypass Fable 5's safeguards. This bypass allowed the model to identify software vulnerabilities and, in one instance, generate code demonstrating how to exploit a specific vulnerability. Anthropic stated that this vulnerability was not unique to Fable 5 and had been observed in less capable models as well. The company developed a new safety classifier to block the reported bypass technique, which was a key factor in the eventual lifting of the controls.

Claude Fable 5 and Claude Mythos 5 were initially launched on June 9, 2026, sharing the same underlying model architecture. Fable 5 is designed for general use with robust safeguards, while Mythos 5 has some safeguards reduced to support defensive cybersecurity partners. Access to Mythos 5 was restored to a select group of US organizations by June 26, 2026, prior to the full lifting of controls on June 30, 2026.

Following the restoration, Claude Fable 5 is available on the Claude Platform, Claude.ai, Claude Code, and Claude Cowork. The pricing for Fable 5 is set at $10 per million input tokens and $50 per million output tokens. The company also introduced a new cybersecurity classifier as part of the model's updated safety features.