Next Mythos-Class Model released by…?

Platform comparison

Market context

Anthropic has already shipped the first Mythos-class release, so the live question is whether a second qualifying model lands before 1 October. Claude Fable 5 went public on 9 June 2026 as a Mythos-class model, with Claude Mythos 5 held back for restricted access and later redeployed more broadly after export controls were lifted on 30 June; that makes the current market a pure follow-on timing bet rather than a binary “will they ever do it” case.

For framing, similar markets around numbered model families usually spend long periods near zero until a launch page, changelog, or pricing update appears, then re-rate fast once the release is public and accessible. A programmatic approach would watch Anthropic’s model docs, release notes, and API model list for a new official name or a fresh “Mythos-class” label, then cross-check whether access is general or only via limited partner channels; a restricted preview would not qualify here.

The main catalysts are scheduled product posts, documentation changes, and any mention of availability on Claude, API partners, or cloud marketplaces. The clearest recent signal was the 1 July redeployment notice restoring Fable 5 globally and reopening Mythos 5 to approved US organisations, which shows Anthropic can move quickly when access constraints change. Traders using alerts or conditional orders would want triggers on Anthropic newsroom updates, the developer docs page, and any partner-cloud release notes, because a qualifying launch must be public by the settlement deadline, not merely announced.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Polymarket Bot UK, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

UK Frequently Asked Questions

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Polymarket Bot UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.