Sep 21, 2026
Probability rose from 59.7% to 65.8% — a 6.2-point move over the past day.
OpenAI IPO Closing Market Cap: Odds & Probability
Prediction markets price Will OpenAI’s market cap be $1.5T or greater at market close on IPO day by December 31, 2027 at 65.8%.
65.8%-0.1 pts 24h
Will OpenAI’s market cap be $1.5T or greater at market close on IPO day by December 31, 2027?
Updated · Volume $335.6K
| Outcome | Probability | 24h |
|---|---|---|
| Will OpenAI’s market cap be $1.5T or greater at market close on IPO day by December 31, 2027? | 65.8% | -0.1 |
| Will OpenAI not IPO by December 31, 2027? | 17.3% | -0.1 |
| Will OpenAI’s market cap be between $1.25T and $1.5T at market close on IPO day by December 31, 2027? | 10.5% | +0.5 |
| Will OpenAI’s market cap be between $1T and $1.25T at market close on IPO day by December 31, 2027? | 4.0% | 0.0 |
| Will OpenAI’s market cap be between $750B and $1T at market close on IPO day by December 31, 2027? | 2.5% | 0.0 |
| Will OpenAI’s market cap be less than $500B at market close on IPO day by December 31, 2027? | 0.7% | -0.0 |
| Will OpenAI’s market cap be between $500B and $750B at market close on IPO day by December 31, 2027? | 0.5% | 0.0 |
The top 5 outcomes account for 98.8% of the total probability.
Context
Sep 16, 2026
Probability fell from 78.0% to 65.5% — a 12.5-point move over the past day.
Sep 14, 2026
Probability fell from 80.3% to 73.7% — a 6.6-point move over the past day.
Around this time: OpenAI IPO won't happen this year, says Sam Altman — CoinDesk
Sep 13, 2026
Probability fell from 80.3% to 78.8% — a 1.6-point move over the past day.
Around this time: OpenAI IPO won't happen this year, says Sam Altman — CoinDesk
Sep 9, 2026
Probability rose from 68.8% to 79.5% — a 10.7-point move over the past day.
Show earlier updates
Sep 8, 2026
Probability rose from 67.3% to 79.5% — a 12.2-point move over the past day.
Sep 3, 2026
Probability rose from 60.0% to 62.4% — a 2.4-point move over the past day.
Sep 2, 2026
Probability rose from 56.2% to 62.9% — a 6.7-point move over the past day.
Aug 16, 2026
Probability rose from 34.6% to 44.0% — a 9.4-point move over the past day.
This probability comes from live prices on prediction markets, where a contract's price equals the implied chance of the outcome. It updates continuously as trading occurs.
This market has 7 tracked outcomes and $335.6K in total trading volume.
The most closely contested outcome, Will OpenAI’s market cap be $1.5T or greater at market close on IPO day by December 31, 2027, is priced at 65.8%.
Data: Polymarket · Methodology · Not financial advice