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icon for OpenAI IPO Closing Market Cap
Finance·IPO

OpenAI IPO Closing Market Cap

icon for OpenAI IPO Closing Market Cap
Finance·IPO

OpenAI IPO Closing Market Cap

Jan 1, 2027

Jan 1, 2028

Jan 1, 2027

Jan 1, 2028

No IPO by December 31, 2026 97.4%

1.5T+ 1.5%

1T–1.25T <1%

750B–1T <1%

Polymarket

$2,157,643 Vol.

No IPO by December 31, 2026 97.4%

1.5T+ 1.5%

1T–1.25T <1%

750B–1T <1%

Polymarket

$2,157,643 Vol.

<500B

$309,241 Vol.

<1%

500–750B

$170,329 Vol.

<1%

750B–1T

$183,037 Vol.

<1%

1T–1.25T

$224,388 Vol.

<1%

1.25T–1.5T

$531,117 Vol.

<1%

1.5T+

$161,198 Vol.

1%

No IPO by December 31, 2026

$578,334 Vol.

97%

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.Sam Altman’s September 12, 2026, statements to Fortune that an OpenAI IPO this year would be “ill-advised” due to the need for AI safety and alignment work represent the dominant catalyst behind the 97.4% market-implied probability of no listing by December 31, 2026. The company’s June confidential S-1 filing and earlier banker discussions of a potential $1 trillion valuation have given way to explicit prioritization of regulatory coordination and risk mitigation over near-term access to public capital, reinforced by comparable delays seen in other high-growth tech floats. Trader consensus reflects the absence of any committed timeline or roadshow activity, plus ongoing scrutiny from lawmakers on frontier model risks. While a rapid resolution of safety issues or shifting market conditions could theoretically reopen a 2026 window, Altman’s comments and internal focus make such an outcome improbable.

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.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.
Volume
$2,157,643
End Date
Jan 1, 2027
Market Opened
Sep 22, 2025, 8:18 PM ET

Resolver

0x2F5e3684c...
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.Sam Altman’s September 12, 2026, statements to Fortune that an OpenAI IPO this year would be “ill-advised” due to the need for AI safety and alignment work represent the dominant catalyst behind the 97.4% market-implied probability of no listing by December 31, 2026. The company’s June confidential S-1 filing and earlier banker discussions of a potential $1 trillion valuation have given way to explicit prioritization of regulatory coordination and risk mitigation over near-term access to public capital, reinforced by comparable delays seen in other high-growth tech floats. Trader consensus reflects the absence of any committed timeline or roadshow activity, plus ongoing scrutiny from lawmakers on frontier model risks. While a rapid resolution of safety issues or shifting market conditions could theoretically reopen a 2026 window, Altman’s comments and internal focus make such an outcome improbable.

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.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.
Volume
$2,157,643
End Date
Jan 1, 2027
Market Opened
Sep 22, 2025, 8:18 PM ET

Resolver

0x2F5e3684c...

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Frequently Asked Questions

"OpenAI IPO Closing Market Cap" is a prediction market on Polymarket with 7 possible outcomes where traders buy and sell shares based on what they believe will happen. The current leading outcome is "No IPO by December 31, 2026" at 97%, followed by "1.5T+" at 1%. Prices reflect real-time crowd-sourced probabilities. For example, a share priced at 97¢ implies that the market collectively assigns a 97% chance to that outcome. These odds shift continuously as traders react to new developments and information. Shares in the correct outcome are redeemable for $1 each upon market resolution.

As of today, "OpenAI IPO Closing Market Cap" has generated $2.2 million in total trading volume since the market launched on Sep 22, 2025. This level of trading activity reflects strong engagement from the Polymarket community and helps ensure that the current odds are informed by a deep pool of market participants. You can track live price movements and trade on any outcome directly on this page.

To trade on "OpenAI IPO Closing Market Cap," browse the 7 available outcomes listed on this page. Each outcome displays a current price representing the market's implied probability. To take a position, select the outcome you believe is most likely, choose "Yes" to trade in favor of it or "No" to trade against it, enter your amount, and click "Trade." If your chosen outcome is correct when the market resolves, your "Yes" shares pay out $1 each. If it's incorrect, they pay out $0. You can also sell your shares at any time before resolution if you want to lock in a profit or cut a loss.

The current frontrunner for "OpenAI IPO Closing Market Cap" is "No IPO by December 31, 2026" at 97%, meaning the market assigns a 97% chance to that outcome. The next closest outcome is "1.5T+" at 1%. These odds update in real-time as traders buy and sell shares, so they reflect the latest collective view of what's most likely to happen. Check back frequently or bookmark this page to follow how the odds shift as new information emerges.

The resolution rules for "OpenAI IPO Closing Market Cap" define exactly what needs to happen for each outcome to be declared a winner — including the official data sources used to determine the result. You can review the complete resolution criteria in the "Rules" section on this page above the comments. We recommend reading the rules carefully before trading, as they specify the precise conditions, edge cases, and sources that govern how this market is settled.