How UMA works
The Optimistic Oracle verifies data in stages
Statement
A statement is proposed as true
A natural-language statement is submitted along with a bond. The bond acts as a bounty for anyone to dispute it if they have evidence to the contrary.
Challenge period
Most statements go undisputed
Anyone can propose an answer to a data request, and it is accepted as true if it is not disputed during the challenge period.
Dispute
Anyone can dispute a statement
Each statement submitted for validation is an opportunity for anyone to earn a reward by disputing it successfully. As the game theory would predict, disputes are rare in practice because the incentives are always to be honest. That makes the OO “optimistic”.
Voting
Tokenholders vote on disputes and earn rewards
The UMA token provides economic guarantees to the Optimistic Oracle. The community of tokenholders provide the human component, as voters, for the OO's final resolution on disputes or queries. Those who vote with the majority earn rewards.
Participate as a Voter
Stake, vote & earn up to 16% APR
Stake
Stake your $UMA to help secure UMA's Optimistic Oracle.
Vote
Token holders who vote correctly and consistently earn higher APYs.
Earn
Successful voters will gradually own a higher percentage of the protocol than unsuccessful or inactive voters.
Participate as a Builder
Launch products with theas your backbone
Prediction Markets
The OO can validate natural-language statements and answer questions about real-world events.
This includes arbitrary questions about weather, sports, elections, markets or anything universally verifiable.
Real question used by Polymarket
“Did the Chiefs beat the Eagles in the 2022-2023 NFL Superbowl?”
pragma solidity ^0.8.14;
contract OO_GettingStarted {
bytes32 identifier = bytes32 ("YES_OR_NO_QUERY");
bytes ancillaryData =
bytes("Q: Did the Chiefs beat the Eagles in the 2022-2023 NFL Superbowl? A:1 for yes. 0 for no.");
uint256 requestTime = 0;
function requestPrice() public {
requestTime = block.timestamp;
IERC20 bondCurrency = IERC20(0xB4FBF271143F4FBf7B91A5ded31805e42b2208d6);
uint256 reward = 0;