Oracle

When a Decentralized Prediction Market reaches its Market Expiry, someone must report the real-world outcome to the smart contract. An oracle handles this by accepting a bonded assertion from any participant claiming a specific outcome. On Polymarket, the UMA Optimistic Oracle accepts a $750 USDC bond from the proposer and opens a 2-hour challenge window. If no one disputes the assertion, the outcome is accepted as correct and Settlement proceeds automatically. This "optimistic" design means the vast majority of markets resolve quickly and cheaply because disputes are rare. The bond mechanism aligns incentives: a correct proposer recovers their bond plus a reward, while an incorrect proposer loses the entire bond.

Oracles solve the fundamental problem of importing trusted data into trustless systems. The security of an optimistic oracle rests on the economic cost of manipulation. For UMA, an attacker would need to acquire a majority of UMA tokens to override DVM voting, which costs far more than any realistic profit from corrupting a single market. The Resolution Source referenced in the Resolution Criteria provides the factual anchor that disputers use when challenging incorrect proposals. When a genuine disagreement arises about the Resolution Criteria, the dispute escalates to token-holder voting, ensuring that no single entity controls the final outcome. This architecture distinguishes decentralized platforms from centralized ones where a company team holds sole resolution authority.