OpenAI IPO closing market cap above ___ ?

This market will resolve to “Yes” if the official closing price for OpenAI's market capitalization on its first trading day is above the listed value. Otherwise, it will resolve to “No”. If no IPO occurs by December 31, 2027, 11:59 PM ET, this market will resolve to “No”. Market capitalization is defined as the total number of outstanding shares multiplied by the closing share price on the first trading day. Resolution will be based on the primary exchange’s official listing page. In the event that the relevant figure is not displayed, another reliable source will be used. In the event of an interruption in the course of the normal trading session on OpenAI's first day of trading (e.g., a circuit breaker or half-day), the market will resolve according to the official closing price of the abbreviated session. If no such official closing price is published, the market will resolve according to the next trading day on which an official closing price is published, treating that as the first day of trading.

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Polymarket uses a central limit order book (CLOB) model — you can buy or sell shares of any outcome at the current market price, or place limit orders. Prices represent implied probability: a $0.65 contract means the market prices a 65% chance of that outcome.