Why Is Mythos Restricted? Two Distinct Reasons Explained

Reason one: safety design (Glasswing-only Mythos 5)

Mythos-class capability sits a tier above Opus. To manage the risk, the public model — Fable 5 — keeps safety classifiers switched on, while the classifier-lifted version — Mythos 5 — is restricted by design to vetted users through Project Glasswing. This is not a temporary outage; it is the intended architecture. Lifting the safeguards is reserved for screened cyberdefense and critical-infrastructure work under oversight.

Reason two: the June 12, 2026 export-control suspension

Separately and more recently, a US government export-control directive issued June 12, 2026 suspended all access to both Fable 5 and Mythos 5. This is an external regulatory action, not a product decision, and it is currently active. It is the reason even Fable 5 — normally available on subscription plans — is unavailable right now. Anthropic has stated it intends to restore Fable 5 to subscription plans when capacity and clearance allow.

Why the distinction matters

Conflating the two reasons leads to confusion. Mythos 5 would be Glasswing-only even without the directive. Fable 5, by contrast, is normally available and is restricted today only because of the export-control suspension. When the directive lifts, Fable 5 is expected to return; Mythos 5 remains a Glasswing-gated product regardless.