Anthropic’s June 2026 release of the safeguarded Claude Fable 5 and restricted Mythos 5 variants set the current Mythos-class performance baseline on the Text Arena leaderboard at lmarena.ai. With no official announcements, leaks, or new capability demonstrations since then, trader sentiment for the next model’s arena debut rests on the lab’s historical three-to-five-month frontier cadence, tempered by ongoing safety evaluations, compute limits, and regulatory scrutiny around agentic and cybersecurity features. Competitive pressure from OpenAI and other labs, combined with easing U.S. oversight after initial restrictions, supports market-implied odds favoring an early-to-mid September public release that could quickly qualify at 1470+ Elo. Key near-term catalysts include any Anthropic developer updates or benchmark rumors that could accelerate or delay the timeline before the December 31, 2026 resolution.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated$14,251 Vol.
Dec 31, 2026
1470+
94%
1480+
89%
1490+
78%
1500+
54%
1510+
15%
$14,251 Vol.
1470+
$2,234 Vol.
94%
1480+
$751 Vol.
89%
1490+
$5,064 Vol.
78%
1500+
$2,889 Vol.
54%
1510+
$3,312 Vol.
15%
This market will resolve to "Yes" if the next Anthropic Mythos-class model added to the Arena.AI Leaderboard (https://arena.ai/leaderboard/text/overall-no-style-control) has at least the specified score at 12:00 PM ET on the calendar date following the date on which it first appears on the leaderboard. Otherwise, this market will resolve to "No".
Any model whose official name includes "Mythos," or "Fable" (e.g., Claude Fable 5.1 or Claude Fable 6), or that Anthropic officially describes as a "Mythos-class" model or similar, will qualify for this market's resolution. Anthropic's other model tiers, such as Opus, Sonnet, or Haiku, will not qualify.
Results from the "Score" column under the "Text Arena | Overall" Leaderboard tab at https://arena.ai/leaderboard/text/overall-no-style-control with style control off will be used to resolve this market. This market will resolve solely based on the specified score in the Score column of the leaderboard, regardless of any underlying granular or unrounded data presented elsewhere.
A model marked "AutoEval" will not be considered added to the leaderboard. Only scores displayed without the "AutoEval" label will be considered.
If multiple models are added to the leaderboard on the same calendar date (ET), the highest-scoring model will be used for resolution. Models added to the leaderboard on the calendar date following the initial qualifying model's first appearance will not be considered. If a model is first added to the Arena.AI Leaderboard but is subsequently removed and not re-added, such that it is not displayed on the leaderboard at 12:00 PM ET on the calendar date following its first appearance, its appearance will not qualify as added to the Arena.AI Leaderboard.
A qualifying model must be newly added to the Arena.AI Leaderboard. Whether the model was previously released, publicly accessible, in beta, or otherwise available before appearing on the leaderboard is irrelevant for this market.
The resolution source for this market is the Chatbot Arena LLM Leaderboard found at https://arena.ai/leaderboard/text/overall-no-style-control. If this resolution source is unavailable at 12:00 PM ET on the calendar date following the date on which the qualifying model first appears on the leaderboard, this market will resolve based on the first subsequent instance at which such a score becomes available on the leaderboard. If it remains unavailable through the end of the seventh day after the qualifying model first appears on the leaderboard or if no qualifying model release occurs by December 31, 2026, 11:59 PM ET, this market will resolve to "No".Anthropic’s June 2026 release of the safeguarded Claude Fable 5 and restricted Mythos 5 variants set the current Mythos-class performance baseline on the Text Arena leaderboard at lmarena.ai. With no official announcements, leaks, or new capability demonstrations since then, trader sentiment for the next model’s arena debut rests on the lab’s historical three-to-five-month frontier cadence, tempered by ongoing safety evaluations, compute limits, and regulatory scrutiny around agentic and cybersecurity features. Competitive pressure from OpenAI and other labs, combined with easing U.S. oversight after initial restrictions, supports market-implied odds favoring an early-to-mid September public release that could quickly qualify at 1470+ Elo. Key near-term catalysts include any Anthropic developer updates or benchmark rumors that could accelerate or delay the timeline before the December 31, 2026 resolution.
This market will resolve to "Yes" if the next Anthropic Mythos-class model added to the Arena.AI Leaderboard (https://arena.ai/leaderboard/text/overall-no-style-control) has at least the specified score at 12:00 PM ET on the calendar date following the date on which it first appears on the leaderboard. Otherwise, this market will resolve to "No".
Any model whose official name includes "Mythos," or "Fable" (e.g., Claude Fable 5.1 or Claude Fable 6), or that Anthropic officially describes as a "Mythos-class" model or similar, will qualify for this market's resolution. Anthropic's other model tiers, such as Opus, Sonnet, or Haiku, will not qualify.
Results from the "Score" column under the "Text Arena | Overall" Leaderboard tab at https://arena.ai/leaderboard/text/overall-no-style-control with style control off will be used to resolve this market. This market will resolve solely based on the specified score in the Score column of the leaderboard, regardless of any underlying granular or unrounded data presented elsewhere.
A model marked "AutoEval" will not be considered added to the leaderboard. Only scores displayed without the "AutoEval" label will be considered.
If multiple models are added to the leaderboard on the same calendar date (ET), the highest-scoring model will be used for resolution. Models added to the leaderboard on the calendar date following the initial qualifying model's first appearance will not be considered. If a model is first added to the Arena.AI Leaderboard but is subsequently removed and not re-added, such that it is not displayed on the leaderboard at 12:00 PM ET on the calendar date following its first appearance, its appearance will not qualify as added to the Arena.AI Leaderboard.
A qualifying model must be newly added to the Arena.AI Leaderboard. Whether the model was previously released, publicly accessible, in beta, or otherwise available before appearing on the leaderboard is irrelevant for this market.
The resolution source for this market is the Chatbot Arena LLM Leaderboard found at https://arena.ai/leaderboard/text/overall-no-style-control. If this resolution source is unavailable at 12:00 PM ET on the calendar date following the date on which the qualifying model first appears on the leaderboard, this market will resolve based on the first subsequent instance at which such a score becomes available on the leaderboard. If it remains unavailable through the end of the seventh day after the qualifying model first appears on the leaderboard or if no qualifying model release occurs by December 31, 2026, 11:59 PM ET, this market will resolve to "No".
Any model whose official name includes "Mythos," or "Fable" (e.g., Claude Fable 5.1 or Claude Fable 6), or that Anthropic officially describes as a "Mythos-class" model or similar, will qualify for this market's resolution. Anthropic's other model tiers, such as Opus, Sonnet, or Haiku, will not qualify.
Results from the "Score" column under the "Text Arena | Overall" Leaderboard tab at https://arena.ai/leaderboard/text/overall-no-style-control with style control off will be used to resolve this market. This market will resolve solely based on the specified score in the Score column of the leaderboard, regardless of any underlying granular or unrounded data presented elsewhere.
A model marked "AutoEval" will not be considered added to the leaderboard. Only scores displayed without the "AutoEval" label will be considered.
If multiple models are added to the leaderboard on the same calendar date (ET), the highest-scoring model will be used for resolution. Models added to the leaderboard on the calendar date following the initial qualifying model's first appearance will not be considered. If a model is first added to the Arena.AI Leaderboard but is subsequently removed and not re-added, such that it is not displayed on the leaderboard at 12:00 PM ET on the calendar date following its first appearance, its appearance will not qualify as added to the Arena.AI Leaderboard.
A qualifying model must be newly added to the Arena.AI Leaderboard. Whether the model was previously released, publicly accessible, in beta, or otherwise available before appearing on the leaderboard is irrelevant for this market.
The resolution source for this market is the Chatbot Arena LLM Leaderboard found at https://arena.ai/leaderboard/text/overall-no-style-control. If this resolution source is unavailable at 12:00 PM ET on the calendar date following the date on which the qualifying model first appears on the leaderboard, this market will resolve based on the first subsequent instance at which such a score becomes available on the leaderboard. If it remains unavailable through the end of the seventh day after the qualifying model first appears on the leaderboard or if no qualifying model release occurs by December 31, 2026, 11:59 PM ET, this market will resolve to "No".
Market Opened: Aug 27, 2026, 6:39 PM ET
Volume
$14,251End Date
Dec 31, 2026Market Opened
Aug 27, 2026, 6:39 PM ETResolution Source
https://arena.ai/leaderboard/text/overall-no-style-controlResolver
0x65070BE91...This market will resolve to "Yes" if the next Anthropic Mythos-class model added to the Arena.AI Leaderboard (https://arena.ai/leaderboard/text/overall-no-style-control) has at least the specified score at 12:00 PM ET on the calendar date following the date on which it first appears on the leaderboard. Otherwise, this market will resolve to "No".
Any model whose official name includes "Mythos," or "Fable" (e.g., Claude Fable 5.1 or Claude Fable 6), or that Anthropic officially describes as a "Mythos-class" model or similar, will qualify for this market's resolution. Anthropic's other model tiers, such as Opus, Sonnet, or Haiku, will not qualify.
Results from the "Score" column under the "Text Arena | Overall" Leaderboard tab at https://arena.ai/leaderboard/text/overall-no-style-control with style control off will be used to resolve this market. This market will resolve solely based on the specified score in the Score column of the leaderboard, regardless of any underlying granular or unrounded data presented elsewhere.
A model marked "AutoEval" will not be considered added to the leaderboard. Only scores displayed without the "AutoEval" label will be considered.
If multiple models are added to the leaderboard on the same calendar date (ET), the highest-scoring model will be used for resolution. Models added to the leaderboard on the calendar date following the initial qualifying model's first appearance will not be considered. If a model is first added to the Arena.AI Leaderboard but is subsequently removed and not re-added, such that it is not displayed on the leaderboard at 12:00 PM ET on the calendar date following its first appearance, its appearance will not qualify as added to the Arena.AI Leaderboard.
A qualifying model must be newly added to the Arena.AI Leaderboard. Whether the model was previously released, publicly accessible, in beta, or otherwise available before appearing on the leaderboard is irrelevant for this market.
The resolution source for this market is the Chatbot Arena LLM Leaderboard found at https://arena.ai/leaderboard/text/overall-no-style-control. If this resolution source is unavailable at 12:00 PM ET on the calendar date following the date on which the qualifying model first appears on the leaderboard, this market will resolve based on the first subsequent instance at which such a score becomes available on the leaderboard. If it remains unavailable through the end of the seventh day after the qualifying model first appears on the leaderboard or if no qualifying model release occurs by December 31, 2026, 11:59 PM ET, this market will resolve to "No".Anthropic’s June 2026 release of the safeguarded Claude Fable 5 and restricted Mythos 5 variants set the current Mythos-class performance baseline on the Text Arena leaderboard at lmarena.ai. With no official announcements, leaks, or new capability demonstrations since then, trader sentiment for the next model’s arena debut rests on the lab’s historical three-to-five-month frontier cadence, tempered by ongoing safety evaluations, compute limits, and regulatory scrutiny around agentic and cybersecurity features. Competitive pressure from OpenAI and other labs, combined with easing U.S. oversight after initial restrictions, supports market-implied odds favoring an early-to-mid September public release that could quickly qualify at 1470+ Elo. Key near-term catalysts include any Anthropic developer updates or benchmark rumors that could accelerate or delay the timeline before the December 31, 2026 resolution.
This market will resolve to "Yes" if the next Anthropic Mythos-class model added to the Arena.AI Leaderboard (https://arena.ai/leaderboard/text/overall-no-style-control) has at least the specified score at 12:00 PM ET on the calendar date following the date on which it first appears on the leaderboard. Otherwise, this market will resolve to "No".
Any model whose official name includes "Mythos," or "Fable" (e.g., Claude Fable 5.1 or Claude Fable 6), or that Anthropic officially describes as a "Mythos-class" model or similar, will qualify for this market's resolution. Anthropic's other model tiers, such as Opus, Sonnet, or Haiku, will not qualify.
Results from the "Score" column under the "Text Arena | Overall" Leaderboard tab at https://arena.ai/leaderboard/text/overall-no-style-control with style control off will be used to resolve this market. This market will resolve solely based on the specified score in the Score column of the leaderboard, regardless of any underlying granular or unrounded data presented elsewhere.
A model marked "AutoEval" will not be considered added to the leaderboard. Only scores displayed without the "AutoEval" label will be considered.
If multiple models are added to the leaderboard on the same calendar date (ET), the highest-scoring model will be used for resolution. Models added to the leaderboard on the calendar date following the initial qualifying model's first appearance will not be considered. If a model is first added to the Arena.AI Leaderboard but is subsequently removed and not re-added, such that it is not displayed on the leaderboard at 12:00 PM ET on the calendar date following its first appearance, its appearance will not qualify as added to the Arena.AI Leaderboard.
A qualifying model must be newly added to the Arena.AI Leaderboard. Whether the model was previously released, publicly accessible, in beta, or otherwise available before appearing on the leaderboard is irrelevant for this market.
The resolution source for this market is the Chatbot Arena LLM Leaderboard found at https://arena.ai/leaderboard/text/overall-no-style-control. If this resolution source is unavailable at 12:00 PM ET on the calendar date following the date on which the qualifying model first appears on the leaderboard, this market will resolve based on the first subsequent instance at which such a score becomes available on the leaderboard. If it remains unavailable through the end of the seventh day after the qualifying model first appears on the leaderboard or if no qualifying model release occurs by December 31, 2026, 11:59 PM ET, this market will resolve to "No".
Any model whose official name includes "Mythos," or "Fable" (e.g., Claude Fable 5.1 or Claude Fable 6), or that Anthropic officially describes as a "Mythos-class" model or similar, will qualify for this market's resolution. Anthropic's other model tiers, such as Opus, Sonnet, or Haiku, will not qualify.
Results from the "Score" column under the "Text Arena | Overall" Leaderboard tab at https://arena.ai/leaderboard/text/overall-no-style-control with style control off will be used to resolve this market. This market will resolve solely based on the specified score in the Score column of the leaderboard, regardless of any underlying granular or unrounded data presented elsewhere.
A model marked "AutoEval" will not be considered added to the leaderboard. Only scores displayed without the "AutoEval" label will be considered.
If multiple models are added to the leaderboard on the same calendar date (ET), the highest-scoring model will be used for resolution. Models added to the leaderboard on the calendar date following the initial qualifying model's first appearance will not be considered. If a model is first added to the Arena.AI Leaderboard but is subsequently removed and not re-added, such that it is not displayed on the leaderboard at 12:00 PM ET on the calendar date following its first appearance, its appearance will not qualify as added to the Arena.AI Leaderboard.
A qualifying model must be newly added to the Arena.AI Leaderboard. Whether the model was previously released, publicly accessible, in beta, or otherwise available before appearing on the leaderboard is irrelevant for this market.
The resolution source for this market is the Chatbot Arena LLM Leaderboard found at https://arena.ai/leaderboard/text/overall-no-style-control. If this resolution source is unavailable at 12:00 PM ET on the calendar date following the date on which the qualifying model first appears on the leaderboard, this market will resolve based on the first subsequent instance at which such a score becomes available on the leaderboard. If it remains unavailable through the end of the seventh day after the qualifying model first appears on the leaderboard or if no qualifying model release occurs by December 31, 2026, 11:59 PM ET, this market will resolve to "No".
Volume
$14,251End Date
Dec 31, 2026Market Opened
Aug 27, 2026, 6:39 PM ETResolution Source
https://arena.ai/leaderboard/text/overall-no-style-controlResolver
0x65070BE91...Anthropic’s June 2026 release of the safeguarded Claude Fable 5 and restricted Mythos 5 variants set the current Mythos-class performance baseline on the Text Arena leaderboard at lmarena.ai. With no official announcements, leaks, or new capability demonstrations since then, trader sentiment for the next model’s arena debut rests on the lab’s historical three-to-five-month frontier cadence, tempered by ongoing safety evaluations, compute limits, and regulatory scrutiny around agentic and cybersecurity features. Competitive pressure from OpenAI and other labs, combined with easing U.S. oversight after initial restrictions, supports market-implied odds favoring an early-to-mid September public release that could quickly qualify at 1470+ Elo. Key near-term catalysts include any Anthropic developer updates or benchmark rumors that could accelerate or delay the timeline before the December 31, 2026 resolution.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated
Beware of external links.
Beware of external links.
Frequently Asked Questions