Method 01 · prediction market
Prediction-market IPO ladder — 2027
Polymarket · 1 source event · 7 outcomes
- Difference from Rai estimate
- -4.0%
- Share of combined estimate
- 25.0%
- Updated
- Aug 12, 2026, 10:22 AM EDT
IPO-cap current equivalent
$1.15TPublic market cap based on outstanding sharesConditional IPO valuation
$1.35TAssuming an IPO by the deadlineDiscounted IPO scenario
$1.19TIPO branch discounted 1.39 yearsProbability of IPO
90.1%By Dec 31, 2027Probability distribution
Normalized market probabilities
The chart shows the probability Rai uses for each possible outcome. Source values and adjustment details are in the audit table.
Open audit table
| Outcome | Raw | Normalized | Assigned value | Contribution |
|---|---|---|---|---|
| Below $500B | 0.8% | 0.8% | $400B | $3.5B |
| $500B–$750B | 3.3% | 3.4% | $625B | $23.9B |
| $750B–$1T | 11.5% | 12.0% | $875B | $116.5B |
| $1T–$1.25T | 20.7% | 21.6% | $1.13T | $269.7B |
| $1.25T–$1.5T | 17.5% | 18.3% | $1.38T | $278.7B |
| Above $1.5T | 32.6% | 34.0% | $1.75T | $660.7B |
| No IPO by deadline | 9.5% | 9.9% | N/A | — |
| Probability total | 95.9% | 100.0% | — | — |
Why Rai normalizes the raw total
These independently traded market prices add up to 95.9%, rather than 100%. Rai scales each probability proportionally so the outcomes form a complete distribution.
This gap is not a Polymarket fee. It can reflect bid–ask spreads, uneven liquidity, or prices recorded at different times. When the gap is relatively large, normalization can meaningfully affect the estimate.
Calculation details
IPO-ladder calculation
All monetary values are calculated internally in millions of US dollars.
- 01100.0%
Normalize the ladder
Each raw probability ÷ 95.9%
- 02$1.35T
Weight IPO outcomes
Σ conditional probability × assigned bracket value
- 03$1.19T
Discount the future IPO branch
IPO scenario ÷ (1 + 10.0%)^1.39
- 04$1.15T
Mix current-equivalent branches
IPO odds × discounted IPO cap + residual odds × current private scenario value of $852B
Assumptions
Configured valuation assumptions
Closed brackets use arithmetic midpoints. Open brackets and the no-IPO scenario use configured values. The no-IPO value is already a current private-company scenario, so it is not discounted again.
Assumptions as of Jul 24, 2026: source and rationale . Scenario inputs translate the source IPO capitalization ladder into current-equivalent dollars. They are not additional market observations.
- Annual discount rate
- 10.0%
- Expected valuation date
- Dec 31, 2027
- Lower open bracket
- $400B
- Upper open bracket
- $1.75T
- Current no-IPO scenario value
- $852B
- Probability method
- Bid–ask midpoint, then last trade
Sensitivity
One-variable sensitivity analysis
Each check varies one configured assumption from its base value.
5.0% discount rate
$1.22T20.0% discount rate
$1.03T$639B no-IPO scenario
$1.13T$1.06T no-IPO scenario
$1.17TSource markets
Polymarket source quotes
Below $500B
Will OpenAI’s market cap be less than $500B at market close on IPO day by December 31, 2027?
- Bid / ask
- 0.7% / 0.8%
- Volume
- $6,079
- Provider / fetched
- Aug 12, 2026, 10:16 AM EDT / Aug 12, 2026, 10:22 AM EDT
$500B–$750B
Will OpenAI’s market cap be between $500B and $750B at market close on IPO day by December 31, 2027?
- Bid / ask
- 3.2% / 3.4%
- Volume
- $8,096
- Provider / fetched
- Aug 12, 2026, 10:16 AM EDT / Aug 12, 2026, 10:22 AM EDT
$750B–$1T
Will OpenAI’s market cap be between $750B and $1T at market close on IPO day by December 31, 2027?
- Bid / ask
- 11.0% / 12.0%
- Volume
- $8,975
- Provider / fetched
- Aug 12, 2026, 10:16 AM EDT / Aug 12, 2026, 10:22 AM EDT
$1T–$1.25T
Will OpenAI’s market cap be between $1T and $1.25T at market close on IPO day by December 31, 2027?
- Bid / ask
- 19.9% / 21.5%
- Volume
- $13,974
- Provider / fetched
- Aug 12, 2026, 10:16 AM EDT / Aug 12, 2026, 10:22 AM EDT
$1.25T–$1.5T
Will OpenAI’s market cap be between $1.25T and $1.5T at market close on IPO day by December 31, 2027?
- Bid / ask
- 17.0% / 18.0%
- Volume
- $7,763
- Provider / fetched
- Aug 12, 2026, 10:16 AM EDT / Aug 12, 2026, 10:22 AM EDT
Above $1.5T
Will OpenAI’s market cap be $1.5T or greater at market close on IPO day by December 31, 2027?
- Bid / ask
- 32.2% / 33.0%
- Volume
- $20,040
- Provider / fetched
- Aug 12, 2026, 10:16 AM EDT / Aug 12, 2026, 10:22 AM EDT
No IPO by deadline
Will OpenAI not IPO by December 31, 2027?
- Bid / ask
- 9.0% / 10.0%
- Volume
- $19,231
- Provider / fetched
- Aug 12, 2026, 10:16 AM EDT / Aug 12, 2026, 10:22 AM EDT
Important limitations
Scope and limitations
Prediction prices may be illiquid, stale, or distorted. Open-ended brackets require judgment. First-day IPO market capitalization is not intrinsic value, and this model does not account for future dilution, capital raised, or operating fundamentals.
This estimate is not an ownership interest in OpenAI, an offer to buy or sell securities, or investment advice.