OpenAI IPO Closing Market Cap: live odds and probabilities
The market favorite is No IPO by December 31, 2026 at 97.3%, ahead of 1.5T+ at 0.9%. $2.6M traded across 7 outcomes.
Favorite
24h move
Volume
Closes
IPOBig TechOpenAIIPOsOpenAI IPO
All outcomes
| Outcome | Probability | 24h |
|---|---|---|
| No IPO by December 31, 2026 | 97.3% | +0.1 |
| 1.5T+ | 0.9% | 0.0 |
| <500B | 0.7% | 0.0 |
| 750B–1T | 0.6% | 0.0 |
| 1T–1.25T | 0.4% | -0.1 |
| 500–750B | 0.4% | 0.0 |
| 1.25T–1.5T | 0.3% | +0.1 |
Prices are the Polymarket mid or last trade at 2026-11-06 02:18 UTC. A price of 64¢ implies roughly a 64% chance. Prices include spread and are not forecasts by BetG8.
Price history
Market rules and resolution
This market will resolve based on OpenAI's market capitalization at the closing price on its first day of trading. If no IPO occurs by December 31, 2026, 11:59 PM ET, the market will resolve to "No IPO by December 31, 2026". Market capitalization expresses the monetary value of a company’s outstanding shares, stated in its pricing currency. It is calculated as the number of shares outstanding multiplied by the closing share price on the first trading day. If the relevant value falls exactly between two brackets, then this market will resolve to the higher range bracket. 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 for purposes of this market.
How to read this market
Frequently asked questions
- Who is favored in "OpenAI IPO Closing Market Cap"?
- As of November 6, 2026, No IPO by December 31, 2026 is the favorite at 97.3%, followed by 1.5T+ at 0.9%.
- When does this market resolve?
- The market is scheduled to close on January 1, 2027. It resolves under Polymarket's rules once the outcome is known, which can be earlier or later than the listed date.
- How much has been traded?
- $2.6M in total and $4K in the last 24 hours, with about $201K of resting liquidity.
- Can I trade this market?
- Polymarket restricts access by location; the US version (Polymarket US) and the offshore site have different rules and fee schedules. Check availability in your jurisdiction. BetG8 earns a referral fee from the Polymtrade links on this page.
Related on BetG8
Data: Polymarket Gamma and CLOB APIs, fetched by BetG8 at the time shown above. Venues may restrict access by location. 18+ only.