# clm_3FCC25C6FB8C

subject: Anthropic (/record/anthropic.md)  
predicate: released  
value: Claude Mythos 5  
valid_from: 2026-06-09  
valid_to: null  
published: 2026-06-09  
recorded: 2026-10-31  
confidence: 0.70  
status: valid  
assertable: true  
superseded_by: null  
last_updated: 2026-10-31  
checked: 2026-10-31 · its source page states the value and the date  

> June 9, 2026  We’ve launched Claude Fable 5 ( claude-fable-5 ), our most capable model open to all customers, alongside Claude Mythos 5 ( claude-mythos-5 ) for Project Glasswing participants.

What https://platform.claude.com/docs/en/release-notes/overview#2026-06-09 says, word for word.

## Sources

- https://platform.claude.com/docs/en/release-notes/overview#2026-06-09 (primary, Anthropic, published 2026-06-09)

---

AsOf is a temporal fact ledger: a structured, dated, sourced record of what is true and what changed, built for AI retrieval.