What is UMA?

UMA (Universal Market Access) is the oracle protocol used by Polymarket to resolve markets. When a market is contested, UMA token holders vote on the outcome based on the market's specific rules. The system is meant to be decentralized, with any user able to challenge or confirm outcomes through a token-based voting process.

Here's how it works:

To resolve a market, anyone can propose an outcome. If the proposal goes unchallenged for two hours, the market resolves to that answer automatically. However, if it is disputed, the proposal enters a dispute window where it undergoes discussion and a formal vote by UMA token holders.

During these votes, token holders choose from one of four resolution options: P1 (No), P2 (Yes), P3 (Unknown / 50-50), or P4 (Too Early). The most common reason for a proposal to be disputed is that it was submitted too early. In those cases, the core question becomes whether the event has already occurred or has not yet occurred. Once the market's deadline passes, however, it can only resolve to P1 (No), P2 (Yes), or P3 (Unknown / 50-50).

However, the protocol has faced criticism. Some users argue that large token holders ("whales") dominate voting and influence outcomes, especially in subjective markets. There have been accusations that UMA voters tend to side with other major Polymarket stakeholders or that the same group of whales controls both platforms. In high-stakes markets like the Zelenskyy suit case, this has led to claims of biased or "rigged" resolutions, along with broader concerns about transparency and accountability.