How Are Prediction Markets Resolved? Oracles and Disputes

You can be right about what happened and still lose the market. A prediction market does not pay on the event. It pays on what its written rules say, read from the source they name, by whoever the platform trusts to read it. The title is a summary. The rules are the contract.

Quick answer

Every market has rules that name the question, the deadline and the source of truth. After the deadline, an oracle, a data feed or the platform’s own team sets the outcome. Winning shares redeem for $1 and losing shares for nothing. A challenged result can take days, and some rules allow a 50-50 outcome that pays $0.50 per share.

What decides the outcome?

The rules, not the title. Polymarket puts it plainly: “The market title describes the question, but the rules define how it resolves.” Kalshi works the same way: a rules summary with the value measured, the timeline and the verification source, and full rules below it.

Defaults matter as much as the question. On Limitless, unless the criteria say otherwise, a market where Yes is not met resolves No. When an event happens in a way the rules did not foresee, the default decides, not common sense.

Who sets the result?

• Optimistic oracle. A proposer posts a bond and the answer stands unless someone challenges it. UMA does this for Polymarket and Predict.fun.
• Price or data feed. A feed reports a value at the deadline and the market settles on its own: Chainlink on Polymarket and Predict.fun price markets, Pyth on most Limitless markets.
• Exchange determination. The markets team applies the rules to data from a named source. This is Kalshi.
• Team review. The team checks the result against the criteria, as Limitless does for markets with no feed.
• Proposal plus staked dispute. A result is published and one user can dispute it by staking tokens. This is Opinion.

How does an optimistic oracle work?

“Optimistic” means a proposed answer is assumed correct unless challenged. On Polymarket, a proposer picks the outcome and posts a bond. A correct, undisputed proposal gets the bond back plus a reward; a wrong or early one loses it. For 2 hours anyone can dispute with a counter-bond of the same size. The first dispute starts a second round. A second dispute sends the question to UMA’s Data Verification Mechanism, a vote by UMA token holders, and the winning side gets its bond back plus half of the loser’s.

Polymarket puts it at about 2 hours undisputed and 4 to 6 days disputed. Predict.fun says a vote can take as long as a week. UMA’s docs add that an automated review can extend the challenge period for flagged proposals.

What happens if a result is disputed?

• UMA markets: a new round, then a vote. On Polymarket the vote can let the proposal stand, reject it, or call it “Too Early” or “Unknown/50-50.”
• Opinion: one dispute per resolution. The disputer stakes OPN, gets it back with an equal reward if the dispute is accepted, and loses it if rejected. If the review times out, the dispute succeeds automatically.
• Limitless: no vote. You contact the team through support, email or Discord. A misresolved market refunds the bet amount, not the $1 payout.
• Kalshi: no public vote. If a market has not settled after the source agency published, you can use “Request to Settle” or contact support.

What is a 50-50 resolution?

A result where neither side wins, so every share pays $0.50. Limitless gives an example: 100 Yes and 50 No shares pay (100 x $0.50) + (50 x $0.50) = $75. Its warning is the part to remember: “A 50-50 resolution is not a refund.” You are paid per share, not what you spent.

How do price markets resolve?

Short up or down markets use feeds, not votes. Polymarket uses a Chainlink TWAP (time-weighted average price): the TWAP at the start sets the price to beat, the TWAP at the end sets the result. Limitless uses Chainlink TWAP for its 5 and 15 minute crypto markets, so a spike at the boundary does not decide the market on its own.

Ties are where venues differ. A flat close is Up on Limitless, which resolves Up when the close is greater than or equal to the price to beat. Predict.fun’s up/down rounds have a third outcome, Flat.

How to read a market’s rules before you trade

1. Read the full rules, not the title. Note any word the outcome hangs on.
2. Find the named source. Will it publish in time, and could it be ambiguous?
3. Find the default. What happens if nothing clearly meets Yes?
4. Check ties, cancellations and “Other.” For price markets, note the feed, the window and how a flat close counts.
5. Check whether a 50-50 is possible. It changes the value of a cheap long shot.
6. Know the dispute path. Hours on a feed, days on a vote.

What this means for a farmer

• Resolution time is locked capital. A stake waiting out a dispute earns nothing, and a market that can go to a vote can hold it for most of a week.
• The edge is in the rules. When the rules say something narrower than the title, that gap is where you get paid or caught.
• Resolved is not paid. Limitless notes that a market can appear resolved in its API before the payout is settled on-chain.

Each prediction market’s project page links its current rules and sources.

Frequently asked

Who decides the outcome of a prediction market? An oracle like UMA, a feed like Chainlink or Pyth, or the platform’s own team, always applying the market’s written rules.

How long does a disputed market take? On Polymarket, 4 to 6 days. Predict.fun says up to a week if it goes to a UMA vote.

What if a market is resolved wrongly? On UMA markets, dispute during the challenge period. On Limitless, contact support; a misresolved market refunds the bet amount.