Anthropic pauses Claude Fable 5, Mythos 5 citing national security
Technology
Anthropic has put its Claude Fable 5 and Mythos 5 AI models on pause after a US government order flagged national security worries.
The concern? There's a chance someone could find a way around the built-in safety systems.
Other Claude models are still up and running.
Anthropic cites GPT-5.5, meets US officials
Anthropic says these vulnerabilities aren't unique: other models, like OpenAI's GPT-5.5, have similar issues.
To sort things out, Anthropic met face-to-face with US officials in Washington over the weekend (mid-June 2026) and discussed the matter so they can bring Fable 5 and Mythos 5 back online soon.