Recent release of Claude Fable 5.1 on September 1 has anchored trader consensus around claude-fable-5.1-max at 85% implied probability for the September 14 resolution. Anthropic positioned the update as its strongest publicly available large language model for complex coding, long-running agentic workflows, and knowledge work, with efficiency gains and benchmark gains over prior Fable 5 and Opus 5 variants on evaluations such as Frontier-Bench and automation tasks. Older Opus 5 and earlier Opus 4.6 releases trail significantly in the latest capability comparisons, leaving little room for reversal before resolution. No major competing model launches or capability shifts have emerged in the interim, reinforcing the market’s view of Fable 5.1 as the clear leader.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updatedclaude-fable-5.1-max 85%
Other 15%
claude-opus-5-high <1%
claude-opus-5-max <1%
$19,930 Vol.
$19,930 Vol.
claude-fable-5.1-max
85%
Other
15%
claude-opus-5-high
1%
claude-opus-5-max
<1%
claude-opus-4-6-high
<1%
claude-fable-5.1-max 85%
Other 15%
claude-opus-5-high <1%
claude-opus-5-max <1%
$19,930 Vol.
$19,930 Vol.
claude-fable-5.1-max
85%
Other
15%
claude-opus-5-high
1%
claude-opus-5-max
<1%
claude-opus-4-6-high
<1%
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".
Market Opened: Sep 3, 2026, 10:16 AM ET
Resolution Source
https://arena.ai/leaderboard/text/overall-no-style-controlResolver
0x69c47De9D...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".
Resolution Source
https://arena.ai/leaderboard/text/overall-no-style-controlResolver
0x69c47De9D...Recent release of Claude Fable 5.1 on September 1 has anchored trader consensus around claude-fable-5.1-max at 85% implied probability for the September 14 resolution. Anthropic positioned the update as its strongest publicly available large language model for complex coding, long-running agentic workflows, and knowledge work, with efficiency gains and benchmark gains over prior Fable 5 and Opus 5 variants on evaluations such as Frontier-Bench and automation tasks. Older Opus 5 and earlier Opus 4.6 releases trail significantly in the latest capability comparisons, leaving little room for reversal before resolution. No major competing model launches or capability shifts have emerged in the interim, reinforcing the market’s view of Fable 5.1 as the clear leader.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated


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