Prediction markets are not always right, but they are rarely quiet. Polymarket traders have pushed the probability of Anthropic releasing its next Mythos-class AI model by September 9, 2026, to 74 percent, a number that reflects real money, real conviction, and a growing read on how quickly the frontier AI lab moves.

Trading volume on the “next Mythos-class model released by” contract family has crossed $233,000. The broader AI model race markets on Polymarket have pulled in more than $6 million in cumulative volume.

What the markets are actually pricing

The September 9 contract sits at 74 percent, but that is just one data point in a cascade of related bets. The odds of a Mythos-class release by September 15 have reached 81 percent, and end-of-month estimates sit at 87 percent.

Beyond the near-term Mythos question, Polymarket traders are also eyeing Anthropic’s broader model lineup. A new Opus model arriving by December 31, 2026, carries 96 percent odds. A new Sonnet model by the same date sits at 85 percent.