Prediction markets are supposed to be the wisdom of the crowd distilled into cold, hard probabilities. But at Polymarket, the world’s largest crypto prediction platform, the “crowd” deciding contested outcomes is really just nine wallets.
A Wall Street Journal analysis found that the ten largest UMA token holders control over 50% of voting power in most Polymarket disputes. When traders disagree about whether a market should pay out, the resolution process is dominated by a handful of whales whose financial interests may not align with getting the answer right.
The oracle problem nobody can fix fast enough
Polymarket relies on UMA’s Optimistic Oracle, a system where token holders vote to settle contested market outcomes. At least 60% of active UMA voters over the past year have been linked to Polymarket accounts, according to the Journal’s reporting. These aren’t dispassionate arbiters. They’re participants with skin in the game, voting on outcomes that directly affect their own positions.
Past interventions by whale voters have already surfaced in high-stakes geopolitical bets, including markets tied to Ukraine and Zelenskyy.
Reforms passed on paper, stalled in practice
In August 2025, UMA passed UMIP-189, also known as MOOV2, a governance update that introduced a whitelist of roughly 37 addresses eligible to participate in voting. The idea was to limit who can propose and vote on dispute resolutions to seasoned, vetted participants, and reduce the noise from trivial disputes clogging the system.
Polymarket, meanwhile, has been exploring a more dramatic structural shift. The platform has floated launching its own POLY token, which would internalize oracle functions and reduce dependence on UMA’s voting apparatus entirely.
The MOOV2 whitelist, while a step toward filtering bad actors, doesn’t fundamentally solve the concentration issue. Whitelisting 37 addresses doesn’t help much if the same whales simply appear on that list. And the POLY token remains in the “considering” phase.
What this means for traders and the broader market
For retail participants, the governance concentration creates an asymmetric playing field. If you’re betting on a contentious outcome, your payout may ultimately depend on how nine whales vote.
Polymarket’s exploration of a native POLY token signals that the platform recognizes UMA’s architecture as a liability rather than an asset. Internalizing oracle functions would give Polymarket direct control over its dispute resolution design.