House Oversight Chair Launches Insider Trading Probe into Kalshi and Polymarket!

The chair of the House Oversight Committee has formally launched a probe into potential insider trading activity on prediction markets Kalshi and Polymarket, according to reports. The investigation signals that congressional scrutiny of the fast-growing prediction market sector has moved from rhetoric to formal oversight action.

Both platforms have seen explosive volume growth around major political and economic events, raising longstanding questions about whether participants with non-public information — political insiders, lobbyists, or connected traders — have been able to profit ahead of public announcements. A formal congressional probe carries subpoena power and can compel platform disclosures that voluntary cooperation would not.

The timing matters: Kalshi recently won a landmark legal battle to offer event contracts in the US, and Polymarket has been expanding its US-facing…