According to Polymarket data as of June 9, traders assign a 60% probability to Anthropic's Claude Mythos model launching publicly by end of today, with $42,212 in volume on the June 9 contract. Polymarket's broader cumulative market shows an 81% probability of release by June 10, rising to 90% by June 30, accumulating $1.578 million in total volume.
On Kalshi, the "Before July 1, 2026" contract sits at 43% implied probability, down 30% as traders cite speculation that Anthropic may release the model under a different name, possibly "Claude Fable." Combined volume across all three contracts has exceeded $2.2 million.