In the first half of this year, the total value of suspicious transactions flagged by the market is expected to be about $200 million.

PANews July 21, a report by Bloomberg Businessweek said that as prediction markets such as Kalshi and Polymarket become increasingly popular and scaled, instances of trading using insider information are surging. Bloomberg’s analysis of about 34k suspicious trades marked by Polysights shows that from January 2026 to June 2026, the total amount of marked suspicious trades was about $200 million. Geopolitical and war-related bets were the main drivers, with Iran-related bets peaking in the last half of February. Among the marked trades, the proportion of funds deposited through U.S.-regulated crypto exchanges was as high as 71%. Profits from the marked suspicious trades were highly concentrated: the top 1% of profitable wallets took more than half of the profits, and 57% of the wallets were created within 24 hours before the trades.

Multiple cases have prompted investigations: U.S. soldiers were accused of using military secrets to profit more than $400k on Polymarket; Israeli reservists were accused of using secret intelligence to bet on events related to Iran. Although Polymarket bans U.S. users, users can bypass the restrictions via VPNs. Goldman Sachs has banned employees from trading prediction markets, and the U.S. Senate has banned members and staff from participating.