- Will claude-fable-5.1-max be the best AI model on September 14, 2026?64¢
- Will claude-opus-5-high be the best AI model on September 14, 2026?2¢
- Will claude-opus-5-max be the best AI model on September 14, 2026?2¢
- Will claude-opus-4-6-high be the best AI model on September 14, 2026?<1¢
- Will any other model be the best AI model on September 14, 2026?37¢
This market will resolve according to the model that has the highest arena rank based on the arena.ai Text Arena (Overall) when the table under the "Leaderboard" tab is checked on the specified date, 12:00 PM ET. Results from the "Rank" column under the "Text Arena | Overall" Leaderboard tab at https://arena.ai/leaderboard/text/overall-no-style-control with style control off (Adjustments: None) and filtered for "Models" will be used to resolve this market. Note: Models marked “AutoEval” at the applicable check time will not be considered, regardless of whether they display a rank or score. No new model will be added to this market after market creation. Any model not explicitly listed in this market will be encompassed under the "Other" option. Models will be ordered primarily by their leaderboard rank at the market’s check time. If two or more models are tied on rank, they will be ordered by their Arena score, including any underlying, unrounded, granular values reflected in the data below the leaderboard. If a tie still remains, alphabetical order of model names as listed in this market group (full string, including suffixes such as “-high” and “-max”) will be used as a final tiebreaker (e.g., if two models remain tied, “claude-opus-5-high” would be ranked ahead of “claude-opus-5-max”). This market will resolve to the model that comes first according to this order. The resolution source for this market is the arena.ai Text Arena (Overall). If this resolution source is unavailable at check time, this market will remain open until the leaderboard comes back online and will resolve based on the first check after it becomes available. If it becomes permanently unavailable, this market will resolve to "Other".
Anthropic’s September 1 release of Claude Fable 5.1-max, which immediately topped independent benchmarks such as the Artificial Analysis Intelligence Index with leading scores on coding, reasoning, and agentic tasks, drives the 62% market-implied odds for that outcome. Traders view the upgrade’s gains in long-horizon performance and knowledge work as sufficient to maintain frontier status through mid-September, ahead of earlier Claude Opus 5 variants. The low single-digit probabilities on Opus models reflect their strong but secondary positioning relative to the newest Fable iteration, while the sizable “Other” share accounts for the slim chance of a surprise release or benchmark shift from competitors before the September 14 snapshot. Resolution criteria focus on demonstrated capabilities at that date, leaving limited time for further model launches to alter the current trader consensus.