Claude Mythos released by…?

Platform comparison

Active sub-markets

Market context

Anthropic confirmed on 26 March 2026 that a data breach had exposed details of Claude Mythos, an unreleased model the company describes as a significant capability step forward in coding, reasoning, and cybersecurity tasks. The leak forced the company's hand on disclosure, though Mythos remains in early access testing rather than public release. The resolution hinges on whether Anthropic formally launches this specific model—or an officially confirmed equivalent—before the end of April 2026.

Historical precedent suggests caution around leaked model timelines. When OpenAI's o1 model details surfaced early, the company maintained its planned release schedule rather than accelerating, citing testing rigour over market pressure. Similarly, Anthropic's track record shows deliberate release cycles: Claude 3 family models arrived months after internal development milestones became known. The current 0% crowd probability reflects scepticism that a four-week window suffices for moving from early access to full release, particularly given Anthropic's stated commitment to safety evaluations before broader deployment.

Traders should monitor Anthropic's official announcements and developer platform updates closely. The company typically signals availability through its website and API documentation; any shift from "early access" to "generally available" status would constitute settlement-triggering evidence. Funding flows into the market depend on clarity around release timelines—traders depositing via Klarna or SEPA rails will want confirmation of Anthropic's public statements before committing capital, as the compressed settlement window leaves minimal room for interpretation disputes.

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). The odds column is filled only where we have clean data — that avoids the made-up numbers that get a network demoted when search engines cross-check against the source venue.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Where can I trade this market with the lowest fees?

On Polymarket Klarna UK, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does it cost to trade on Polymarket Klarna UK?

Zero. Polymarket Klarna UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, Polymarket Klarna UK triggers a quick verification flow that finishes in minutes.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.