OpenAI’s market cap between $500B and $750B at market close on IPO day by December 31, 2027
500–750B is priced at 9¢ on Polymarket. Current book: 4¢ bid, 14¢ ask, 10¢ spread. This outcome ranks #4 of 7 inside OpenAI IPO Closing Market Cap.
Price history
9¢ current
−8¢Contract brief
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, 2027, 11:59 PM ET, the market will resolve to "No IPO by December 31, 2027". 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.
Outcome
500–750B
Rank
#4 of 7
Leader
1.5T+ 41¢
Range
4¢-41¢
Family volume
$21K
Identifier
0x59273d3a...a09e
Jun 7, 2026, 9:38 PM UTC · 16m ago
Implied probability
Bid
4¢
Ask
14¢
Spread
10¢
24h volume
$39
Family rank
#4 of 7
7 outcomes · OpenAI IPO Closing Market Cap
Closes
Dec 31, 2027
Family volume
$21K
Orderbook snapshot
4 / 14¢
Contract terms
What resolves this market.
YES condition
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, 2027, 11:59 PM ET, the market will resolve to "No IPO by December 31, 2027". 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.
Venue
Polymarket
Closes
Dec 31, 2027
Identifier
0x59273d3a…a09e
Event family
OpenAI IPO Closing Market Cap.
The same race as a probability stack: rank, volume, and where this contract sits against the other outcomes.
Total volume
$21K
Outcomes
7
Highest price
1.5T+ 41¢
Current share
3%
1.5T+
polymarket · 0x258cf80073b2deb3b08b53bd96715db3924458eb6d80ad670089cc639aa00260
1.25T–1.5T
polymarket · 0x0d03656e2a8161736c1165ad844c40d636e240804c220fc7d63565cfbe79422e
1T–1.25T
polymarket · 0x3d876fb6a2136d8aeabb3f6b3c5129af020b8bf3139175c27e94d3c11cfad8c3
500–750B
polymarket · 0x59273d3af89fe2ad2115f15c2102dc3511b246c3ba1960978cd99f7f6c35a09e
No IPO by December 31, 2027
polymarket · 0x761b434b358af3e666e36d33a6c3dbfe05bd151957729f62f6820c1c2f98e9b8
750B–1T
polymarket · 0x8e2476aedbf95b6abfc78987b24e4404b02ee3b0609c1a254938a95bdadbeef4
<500B
polymarket · 0x94f5db837b2d95d30fde488e64f5582b9e6ec0554a0d79a5e1715f3c3e42584f
Indicators
Yield, cliff risk, volatility, and regime.
Regime
neutral
Score
0.5
Full indicator table
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How we compute these odds
SimpleFunctions aggregates live prediction-market contracts from Kalshi and Polymarket. Each slug groups contracts that resolve on the same underlying event, identified by venue event_id.
For binary slugs, the headline probability is the liquidity-weighted mid-price across all bound contracts. For multi-outcome slugs (e.g. elections with 3+ candidates), the headline is the leader’s price; we never arithmetically average disjoint outcomes — that would produce a number with no real-world meaning.
Snapshots refresh every 5 minutes during market hours; daily aggregates are computed at 04:00 UTC. The 30-day sparkline is drawn from per-ticker daily means stored in market_indicator_daily; 24h delta and movement events are derived from the same source.