This week, Polymarket and Kalshi confirmed several cases of insider trading on their platforms – the most prominent being the arrest of Gannon Ken Van Dyke, a US special forces soldier, in connection with Polymarket’s involvement in the January kidnapping of former Venezuelan President Nicolás Maduro.
Major stock market companies say they are pursuing disciplinary action in insider trading cases and cooperating with law enforcement and regulators, but have said nothing about reimbursing everyday people who unknowingly trade in risky markets.
Using first-hand knowledge of the war plans, prosecutors said, Van Dyke placed more than $400,000 in bets of just over $33,000 on the following event markets:
- “Maduro out on January 31, 2026?”
- “Trump Invoking War Powers Against Venezuela on January 31st?”
- “US troops in Venezuela on January 31, 2026?”
- “Will the US invade Venezuela on January 31, 2026?”
As of Friday afternoon, Polymarket had not added any notes to these marketplaces’ pages about refunds, and had no information about refunds on X or Discord, where they usually post updates. The company did not respond to Money’s requests for comment.
On X, several users asked if Polymarket would refund bettors on markets affected by insider trading or manipulation.
“So you’re going to refund the money for the bet right? Since the competition and odds were illegally damaged,” asked another user, responding to Polymarket’s tweet about Van Dyke’s case.
“What happens now? Does Polymarket refund the money?” someone else wrote on Thursday.
That second post actually referred to the Paris weather markets that were allegedly manipulated by a man who used a heating device (like a hair dryer) to influence temperature readings at Charles de Gaulle Airport. Those markets were:
- “The highest temperature in Paris on April 6?”
- “The highest temperature in Paris on April 15?”
Like the other four markets, there were no notes on the Polymarket website on Friday about refunds to traders who bet on the weather in Paris over the two days.
According to its terms of service, Polymarket summarizes its strict policy regarding refunds: “Contracts such as the Contracts available on the Platform are highly testable, risky, and volatile. Transactions entered into in connection with the Contracts are irreversible, final and non-refundable,” it reads.
According to PolymarketGuide, a community-maintained site, Polymarket sometimes issues refunds “when a market is issued with erroneous rules, is submitted too late, is removed before a decision or its rules change after implementation.” The guide adds: “In rare cases, Polymarket may decide to make users whole when the market settles incorrectly.”
Notifications about refunds are usually posted on the Polymarket Discord channel called “market updates.” Refunds were issued in most markets in the month of April alone, according to customer support messages on the channel. But none of them are the markets mentioned above.
On Wednesday, Kalshi announced fines and penalties in three separate cases of betting against Congress candidates for their personal bets. Kalshi did not respond to Mali’s request for comment on the possibility of refunds for traders using those markets.
More from Mali:
Prediction Markets Have an Insider Trading Problem. Are They Still Worth Gambling?
Prediction Markets 101: Read This Guide Before You Start Placing Bets
Online Sports Betting Gains Popularity — At The Cost Of Traditional Investments
