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Latest / Frontier models and safety

Model releaseFrontierDefenceUSConfirmed

Anthropic launches Claude Fable 5 for general use and Mythos 5 for cyber defenders

See how this story connects

Source: Anthropic: Claude Fable 5 and Claude Mythos 5

Anthropic launched Claude Fable 5, a Mythos-class model it said exceeds any model it had made generally available, with conservative safeguards that route some queries to Claude Opus 4.8 and trigger in under 5% of sessions on average. It also launched Claude Mythos 5, the same model with some safeguards lifted, for cyber defenders through Project Glasswing in collaboration with the US government. Both cost $10 and $50 per million input and output tokens.

Why it matters

Anthropic’s most capable generally available model arrived with safeguards that route some requests to an older model, three days before a US export-control order suspended it.

When
9 Jun 2026
ID
WTA-N-2026-0168
Who
Anthropic

Summary by wheresthe.ai, from Anthropic. Checked against the source on 9 Oct 2026.

Read the original at Anthropic

Source copy: download the page as saved on 18 Oct 2026 (PDF). Also held by the Internet Archive.

Next stop on this Storyline: Led toUS export-control order forces global shutdown of Claude Fable 5 and Mythos 5

Cite this story

WTA-N-2026-0168: “Anthropic launches Claude Fable 5 for general use and Mythos 5 for cyber defenders.” wheresthe.ai, 9 Jun 2026. https://wheresthe.ai/d/anthropic-claude-fable-5-mythos-5-launch-2026-06/ (source: Anthropic: Claude Fable 5 and Claude Mythos 5).

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