
--
Will Microsoft be the largest company in the world by market cap on June 30?
24h Vol
$538.5K
Liquidity
$259.5K
Spread
0%
6/30/2026
View marketFinance
Polymarket market
Track live probability, outcome prices, volume, liquidity, and resolution details for Will OpenAI have the highest IPO Market Cap 2026?. The market currently shows a live probability of 4%, $1.2K in 24h volume, and $13.5K in liquidity.
Probability
4%
24h Volume
$1.2K
Liquidity
$13.5K
This market asks whether OpenAI will end 2026 with the highest market capitalization among all companies that go public during the year. Because OpenAI is one of the most closely watched private companies in AI, any IPO would attract attention well beyond the tech sector. The key question is not just whether OpenAI lists, but whether its first-day valuation tops every other 2026 IPO.
For this market to resolve Yes, OpenAI would need to complete an initial public offering between January 1 and December 31, 2026, and then have the largest U.S.-dollar market cap based on its official closing price on the first trading day. Market cap here means outstanding shares multiplied by that first-day closing price, using the primary exchange’s official listing page as the main source. If OpenAI does not IPO in that window, or if another 2026 IPO finishes its first trading day with a larger market cap, the market resolves No.
OpenAI matters because it is a high-profile artificial intelligence company with an unusually large private-market profile, so its public debut could be one of the biggest corporate listings of the year. The uncertainty is twofold: whether an OpenAI IPO happens at all in 2026, and how its debut valuation compares with other companies that list that same year. The market is effectively pricing disagreement about both the timing of any listing and the size of the opening valuation.
The biggest event-specific drivers are signals that OpenAI is preparing to list, such as filing activity, comments from the company, or any indication of timing and exchange venue. News about other 2026 IPO candidates can also matter, because OpenAI only wins this market if its first-day market cap exceeds every other eligible IPO’s. Changes in expected share count, pricing range, or demand for the offering would be especially important because the resolution depends on the first official close, not later trading.
Related markets

--
24h Vol
$538.5K
Liquidity
$259.5K
Spread
0%
6/30/2026
View marketThe current market price implies roughly a 4% chance for the leading outcome, based on live Polymarket pricing. That number is not a prediction from PredictionNinja and it is not a guarantee; it is the current crowd-priced view of the market and can change quickly when new information appears.
Readers should verify whether OpenAI actually completes an IPO by the end of 2026 and, if it does, what the official first-day closing price and outstanding share count are on the primary exchange listing page. The market uses the company’s first trading day, not later performance, and any currency conversion would follow the Federal Reserve H.10 rate if needed. It is also worth checking the comparison set carefully: only companies that IPO during 2026 count, and a tie is broken alphabetically by listed name.
Track live probability, outcome prices, volume, liquidity, and resolution details for Will OpenAI have the highest IPO Market Cap 2026?. The market currently shows a live probability of 4%, $1.2K in 24h volume, and $13.5K in liquidity.
Track live finance prediction markets focused on interest rates, inflation, stock market events, central bank decisions, and global financial forecasting trends.
Yes
3.9%
No
96.2%
This market is currently listed with an end date of Dec 31, 2026. Market timelines can change if the underlying event is postponed, rescheduled, or resolved early.
This market will resolve to the company that achieves the highest market capitalization in U.S. dollars based on the official closing price on its first trading day in 2026. This market will resolve to a company that completes an Initial Public Offering (IPO) between January 1 and December 31, 2026, 11:59 PM ET. Market capitalization is defined as the total number of outstanding shares multiplied by the closing share price on the first trading day. If two or more companies have exactly equal highest closing market capitalizations, this market will resolve to the company whose listed name comes first alphabetically. 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 case the respective company's primary exchange’s official listing page does not report in U.S. dollars, it will be converted to U.S. dollars using the U.S. Federal Reserve Board’s H.10 foreign exchange reference rate for the relevant currency pair on the company’s first trading day (https://www.federalreserve.gov/releases/h10/). If no such rate is available for the relevant trading day, the most recent previously published rate will be used. If the relevant currency is not listed, another credible exchange rate source will be used. A listed company may resolve to "No" as soon as it becomes unable to complete an IPO, including due to acquisition, merger, or absorption by an entity that is already publicly traded. In the event of an interruption in the course of the normal trading session on the respective companies’ 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.
Probability signal
The current price implies a lower-probability outcome, which can make the market more sensitive to surprise news.
Liquidity context
Liquidity is relatively deep for a prediction market page, so quoted prices may be more reliable than very thin markets.
Spread
The bid-ask spread is tight, which usually points to a more actively priced market.
Recent movement
The 24h move is modest, suggesting the market has not repriced dramatically in the latest feed.
The current displayed probability is 4%, based on the latest normalized Polymarket data available to PredictionNinja.
The rules and resolution criteria are pulled from the market description provided by Polymarket when available.
Prediction markets can move whenever traders react to new information, liquidity changes, injuries, announcements, news, or other event-specific developments.
No. PredictionNinja displays market data and context for research only. It is not financial, legal, betting, or investment advice.

+12.9%
24h Vol
$168.2K
Liquidity
$177.3K
Spread
0%
12/31/2026
View market
-1%
24h Vol
$77.6K
Liquidity
$57.6K
Spread
1%
7/1/2026
View market
--
24h Vol
$33.2K
Liquidity
$128.3K
Spread
0%
12/31/2026
View market
-0.3%
24h Vol
$18.7K
Liquidity
$28.3K
Spread
1%
Live
View market
-0.3%
24h Vol
$22.5K
Liquidity
$29K
Spread
0%
6/30/2026
View market