The biggest prediction market controversies weren't bad luck. They came from how the markets are built. Here is each one, replayed.
| PolymarketKalshi | KLEOS | |
|---|---|---|
| Who creates markets | The platform's team | The team and tier-V traders, with a bond they lose if the question is ruled ambiguous |
| Who sets the price | Money only | Money, plus a reputation-weighted price beside it |
| Who resolves | Token holders or the platform | Earned reputation, no position in the market |
| Resolution rules | Often clarified after the fact | Written on-chain before the first bet, shown before you confirm |
| A whale's edge | Moves the headline odds | Moves the money price; the signal holds |
| Forecaster track record | Invisible | Public, on-chain, auditable per bet |
| Insider long shots | Paid out, caught later if at all | Flagged, reputation gains held for review |
| Payout per dollar | Same for everyone | Same for everyone, plus a bonus for beating the market |
| Disputes | Token-weighted votes, voters may hold positions | Kleos Court: 5 random tier-V jurors, no stake, hidden votes, can refund ambiguous markets |
| Opinions | Comments, detached from bets and never scored | Calls tied to real bets, public before the outcome, scored after it |
| Getting started | Wallet extension, seed phrase, bridge funds | A passkey. Gas and test money are sponsored |
Flip each case to see what changes on Kleos, and what doesn't.
“Will Zelensky wear a suit before July?” At the June 24 NATO summit he wore a black blazer, collared shirt and suit trousers; many outlets called it a suit.
First resolved “Yes”. After challenges it went to a UMA token-holder vote, which ruled “No” on July 1, citing a lack of consensus in credible reporting.
After Khamenei was killed, Kalshi did not pay “Yes”. It settled at the last traded price before his death, citing a rule against profiting from death.
The exchange rulebook, through a carve-out many traders say they hadn't seen. Kalshi said it would reimburse all fees and fully refund anyone who bet after the death. A class action followed.
SourcesForbes ↗The Block ↗