Polymarket has found itself in the spotlight again, and this time it’s not about whether Jesus would come in 2025 or when Bitcoin hits a new high.
A $12 million prediction market bet on whether Ukrainian President Volodymyr Zelensky wore a suit to a NATO meeting has ignited debate, casting doubt on the reliability of decentralized resolution systems and how much influence financially invested voters might really have.
A suit, a snapshot, and a $12M gamble
The market in question, hosted on Polymarket, asked a seemingly simple question: Will Zelenskyy wear a suit before July?
It attracted nearly $150 million in total volume. Blockchain sleuth @defipolice_ as called out Polymarket concerning the situation as it became one of the most-watched event markets on the platform.
The sleuth said UMA voters may resolve the bet as NO because whales have financial incentives to do so.
@defipolice_ mentioned that 40+ news outlets already confirmed Zelensky wore a suit and if UMA resolved the bet as NO, it will be “dangerous” as UMA’s credibility as an oracle will collapse and Polymarket will lose users.
The sleuth urged Polymarket to act accordingly and take a "step of integrity" or replace UMA with another oracle.
Notably, Polymarket, a decentralized prediction market, utilizes UMA's (Universal Market Access) Optimistic Oracle as part of its resolution mechanism to determine the outcomes of its betting markets.
The Optimistic Oracle is designed to provide a decentralized and trustless way to resolve market outcomes by allowing proposers to submit data, which is then subject to a challenge period.
If unchallenged, the submitted data is accepted as truth. However, if disputed, the resolution falls to UMA’s Data Verification Mechanism (DVM), where UMA token holders vote to finalize the outcome.
In the context of the Zelensky suit market, the reliance on UMA’s oracle has been a point of contention, with critics alleging that token holders with financial stakes may manipulate votes.
The bet stems from the fact that Zelensky had previously stated he wouldn’t wear a suit until the war was over, a stance echoed by media outlets like The Kyiv Independent.
However, photos from the June 24 NATO summit in the Netherlands showed Zelensky wearing what many identified as a suit, prompting speculation and argument over the market’s resolution.
That resolution, however, hasn’t been finalized.
UMA’s Optimistic Oracle, which helps determine market outcomes on Polymarket, is under fire after voters, many of whom also had stakes in the bet, began submitting conflicting claims.
Critics point to the overlap between voters and bettors as a structural vulnerability.
The lack of KYC (Know Your Customer) requirements allows anonymous accounts to participate, making it harder to ensure impartiality.
Calls for change and the rise of AI-powered oracles
This isn’t the first time decentralized oracles have come under scrutiny. A 2021 Journal of Financial Economics study warned that oracles run by financially incentivized voters could be manipulated.
With billions of dollars flowing through Polymarket, including $3.2 billion on the 2024 U.S. election alone, calls for reform are gaining traction.
Some in the crypto community are looking to AI for solutions. Solana-based PNP Exchange, for example, promotes LLM-based oracles as a more neutral alternative.
Others like Chaos Labs’ Edge Proofs Oracle are experimenting with AI to verify historical data. Meanwhile, platforms such as Truemarketsorg are exploring more transparent or KYC-compliant mechanisms.
As for Polymarket, it has yet to release an official resolution.
But with trust on the line, the outcome may end up being far more significant than whether or not Zelensky wore a suit.
