# OpenAI IPO Closing Market Cap: 500–750B

> 500–750B leads at 8%, runner-up 5% across 2 winner-take-all outcomes — refreshed 42 min ago.

URL: https://simplefunctions.dev/odds/openai-ipo-closing-market-cap-500750b
Updated: 2026-06-08T06:20:11.957Z
Category: technology · Topic: ai-tech
Status: active
Closes: 2027-12-31

## Headline

- Leader: 500–750B at 8%
- Runner-up: 500–750B at 5%
- Outcomes: 2 (winner-take-all)
- Venue: Polymarket (2 contracts)
- 24h volume: $214

## Bound contracts (2)

| Outcome | Price | 24h | Volume | Venue | Slug |
|---|---|---|---|---|---|
| 500–750B | 8¢ | −1pp | $39 | polymarket | /markets/openai-ipo-closing-market-cap-500750b-polymarket-0x59273d3af89fe2ad2115f15c2102dc3511b246c3ba1960978cd99f7f6c35a09e |
| 500–750B | 5¢ | ±0 | $175 | polymarket | /markets/openai-ipo-closing-market-cap-500750b-polymarket-0x3f9f68feccc892303834833665bf204632438b028254fc2d5bceea757ff61ed3 |

## 30-day trajectory

| Day | 500–750B | 500–750B |
|---|---|---|
| 2026-05-09 | 16 | 3 |
| 2026-05-25 | 5 | 9 |
| 2026-06-01 | 8 | 5 |
| 2026-06-08 | 8 | 5 |

_31 days of price history captured. Each row is the daily mean of intraday 5-min captures._

## What moved the line

- 2026-06-06 · 500–750B +4pp 7→11¢ · polymarket
- 2026-06-01 · 500–750B +3pp 5→8¢ · polymarket

## Analysis

This probability represents the market's assessment that OpenAI will complete an initial public offering with a closing market capitalization between $500 billion and $750 billion. At 19%, traders view this outcome as unlikely relative to other valuation scenarios. The low probability reflects several crosscurrents: OpenAI's stated preference for remaining private, uncertainty about IPO timing (related contracts price "no IPO by December 31, 2026" at 73%), and disagreement about potential valuation if a listing occurs (other contracts show higher valuations commanding only 11% probability). The main factors keeping this specific band depressed are that market participants appear to favor either no near-term IPO or significantly higher valuations ($1.5T+). Resolution depends primarily on OpenAI's actual IPO announcement and subsequent market performance, though there are no scheduled announcements or fixed deadlines currently driving near-term probability movements.

### Key factors

- OpenAI has not announced public IPO plans; 73¢ Polymarket contract pricing "no IPO by end-2026" suggests market expects continued private status through year-end
- If an OpenAI IPO occurs, market participants assign only 11% probability to the $1.5T+ valuation band, implying consensus belief in either lower valuations or no listing at $500–750B range
- The $500–750B band represents a moderate valuation; higher-strike contracts ($1.6T+) trade at 30¢, indicating meaningful probability mass above this range
- Trading volume across OpenAI IPO contracts ($2–2.3K daily) is lower than comparable SpaceX IPO contracts ($2.7–2.5K), suggesting less certainty or conviction among traders
- The 19% probability for this specific band depends on conjunction of two events: (1) IPO occurring before or concurrent with 2026 close, and (2) valuation landing in this narrow $250B band rather than above or below

## Methodology

Headline is the **leader's price**, not an arithmetic mean — averaging disjoint winner-take-all outcomes is meaningless. Per-outcome prices come from the venue's last-traded mid; cross-venue values are simple means across contracts on each venue.

## How to use this data

- HTML: https://simplefunctions.dev/odds/openai-ipo-closing-market-cap-500750b
- JSON: https://simplefunctions.dev/api/public/odds?slug=openai-ipo-closing-market-cap-500750b
- Topic hub: https://simplefunctions.dev/predictions/ai-tech

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