Governance Attack Strikes Polymarket: UMA Tycoon Manipulates Vote for Profits

Last night, a governance issue on Polymarket was reported, where a large UMA holder allegedly used last-minute voting to manipulate the system, avoid losses, and profit from an inaccurate market outcome.

A governance attack occurred on Polymarket, where a UMA tycoon used his voting power to manipulate the oracle, allowing the market to settle false results and successfully profit. The tycoon cast 5 million tokens through three accounts, accounting for 25% of the total votes.… pic.twitter.com/3xFuzdRfWJ

— Wu Blockchain (@WuBlockchain) March 26, 2025

The market in question was about whether Ukraine would sign a mineral agreement with Trump before April. As of the market settlement, no official agreement had been made. While Trump said he “expected” to sign the deal soon, it was never formally signed or announced.

Despite this, Polymarket decided the result as ‘YES’, which raised concerns about fairness, as the rules seemed to allow changing outcomes to prevent losses.

UMA Tycoon Controls 25% of Votes to Profit

A UMA tycoon used their voting power to manipulate the oracle, causing the market to settle on false results and make a profit. By casting 5 million tokens across three accounts, they controlled 25% of the votes.

Polymarket acknowledged the issue with the Ukraine Rare Earth Market, where the outcome didn’t match user expectations. Since it was not a market failure, Polymarket shared that they cannot offer refunds. Polymarket is working with the UMA team to prevent this from happening again and is focused on improving their systems, rules, and clarification processes.

Negligence or Manipulation? Polymarket and UMA’s Last-Minute Actions Lead to Controversy

However, an X user noted that there was no governance attack and this was just extreme negligence from both Polymarket and UMAprotocol.

It started with a user proposing a “Yes” answer to a market about Ukraine giving Trump rare earth metals before April, which was disputed, starting the UMA vote process. After all votes were committed, Polymarket issued a last-minute clarification saying the market wasn’t ready to resolve yet. Despite this, UMA whale voters revealed “Yes” votes to avoid penalties, as they could have abstained or rolled the vote.

The “Yes” vote prevailed, and the market ultimately resolved in line with UMA’s decision, rather than Polymarket’s last-minute clarification. The user highlighted that the confusion stemmed from Polymarket’s late intervention, which would have been more effective if issued earlier. The UMA whales, who consistently participate in these disputes, voted strategically to protect their rewards, rather than attempting to manipulate the system.

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