Will OpenAI close its first day of public trading in 2026 with a market cap of $1 trillion+?
As of Oct 3, 2026, 3:20 PM ET, Manifold priced this market at 5.4% (down from 12.2% 24 hours earlier). It had Ṁ150 traded in the past 24 hours and Ṁ100 of order-book liquidity. probcast.co rates the support behind this price as moderate.
A repricing with partial backing — read the new probability with some caution.
The pricing has partial support: moderate trading volume.
How credible was the move?
Three separate questions — a move can be genuine while the latest price is still settling. Methodology →
Move validity
Is the move backed by real trading and depth?
ModerateThe pricing has partial support: moderate trading volume.
Consensus stability
Has the market settled at the new probability?
StableThe probability has held near its current level over the past several hours.
Contract clarity
Will the rules resolve without ambiguity?
HighThe resolution rules are relatively specific, with a named source and a defined deadline.
From the latest trade tape (most recent 200 prints) — a live activity sample, not a lifetime total.
What this market actually measures
Resolves YES if: OpenAI common stock begins trading on a public exchange on or before December 31, 2026, AND its market capitalization at the close of its first full trading day is ≥ $1.00 trillion USD. Terms: • Resolves NO if trading has not begun by Dec 31, 2026 (delay, withdrawal, or acquisition all count as NO).
This summary shows the opening of the venue's official rules. ProbCast has not yet generated an independent plain-English interpretation for this contract — review the full rules before relying on it.
View full official resolution rules
Resolves YES if: OpenAI common stock begins trading on a public exchange on or before December 31, 2026, AND its market capitalization at the close of its first full trading day is ≥ $1.00 trillion USD. Terms: • Resolves NO if trading has not begun by Dec 31, 2026 (delay, withdrawal, or acquisition all count as NO). This is deliberate — the market prices both timing risk and valuation. • Market cap = first-day closing price × total shares outstanding as reported by at least two of: Bloomberg, Reuters, WSJ, or the exchange itself. If outlets split on basic vs. diluted share count, use basic shares outstanding per the final prospectus. • Direct listing counts the same as a traditional IPO. A listing of a parent/successor entity counts if it’s the primary vehicle for OpenAI’s business. • First-day close means the regular-session close, ignoring after-hours.
Why the odds moved
The probability fell 6.8 percentage points over the last 24 hours (12.2% → 5.4%).
No verified catalyst has been linked to this move yet. ProbCast does not attribute moves to news without evidence connecting the timing of a specific report to the repricing.
What could move this market next?
- The market's deadline arrivesDecember 31, 2026 at 6:59 PM ET
The contract must resolve based on what has happened by this date.
Derived from the contract's own mechanics as of Oct 3, 3:33 PM ET. ProbCast does not list scheduled meetings, announcements, or data releases it cannot verify.
Advanced analysis (experimental)
Research signals — these models are still accumulating the history needed for full validation, and they can disagree with the headline read. Model confidence: low · expected error ±22 pts.
What's happening
Thin book and/or wide spread. Small orders can move this price disproportionately, so any single print is noisy and easily overread.
- Thin book and/or wide spread.
Read with caution —Read the latest price with caution; conditions make it an unreliable summary right now.
More details — reliability score, dynamics, durability
- Illiquid / quiet99%
Short-term motion of the price line (~1h), distinct from the environment above — not a prediction of the final outcome.
A read-only classification of the market environment — how much weight the current price deserves as a read of consensus. It describes conditions, never a trade.
Market data
24h volume
Ṁ150
Liquidity
Ṁ100
Total volume
Ṁ512.6
- Category
- AI / Tech
- Venue
- Manifold
- Open interest
- —
- Current probability
- 5.4%
- 7-day range
- 5.4% – 12.2%
- Resolves
- Dec 31, 2026