Anthropic IPO bets draw tens of millions to prediction markets

Prediction-market traders poured tens of millions of dollars into contracts tied to Anthropic’s proposed initial public offering after the artificial-intelligence company filed its S-1 registration statement with the Securities and Exchange Commission. The contracts let participants wager on the timing, size, valuation and mechanics of an offering whose share count and price range have yet to be set.

Anthropic said on Oct. 26 that it intended to list Class A common stock on the Nasdaq Global Select Market under the symbol ANT. Reuters reported that the proposed flotation could value the company between $1.5 trillion and $2 trillion.

More than a dozen Polymarket markets were created around the IPO, covering the fundraising total, listing exchange and valuation at the debut. By 9:30 a.m. ET on Oct. 28, Polymarket’s contract on the timing of the IPO had traded $6 million, while a separate contract on Anthropic’s closing market capitalization had generated about $3 million.

Kalshi drew bets on which bank would lead the offering and how sector-index providers would classify the company.

The markets use yes-or-no event contracts rather than Anthropic shares. Their prices change as traders buy and sell claims tied to real-world outcomes, creating a way to take a view on an IPO’s features without buying shares. IPO investing has historically been dominated by institutions, even as retail participation has broadened in recent years and issuers still reserve only a small share of offerings for individual investors.

Michael Ashley Schulman of Cerity Partners described the interest as “the financial equivalent of people lining up outside the Apple Store before a new iPhone release.” He said the wagers could help the market narrow estimates of Anthropic’s eventual opening price, while Steve Sosnick of Interactive Brokers called the IPO a test of individual and institutional appetite for AI.

The activity illustrates prediction markets’ expansion from politics and macroeconomic data into company-specific Wall Street events. In a June proposal, the Commodity Futures Trading Commission said the number and variety of event contracts had increased significantly, and that market-set prices can aggregate information about an event’s probability. CFTC-registered prediction markets recorded more than $25 billion in trading volume in 2025, though that remained small beside the roughly $31 trillion notional value of the overall futures market that year.