Sources: Kalshi has probed and flagged 400+ suspicious trades YTD, more than 2x the number it investigated in all of 2025; Polymarket has seen a similar uptick (Anirban Sen/Reuters)

Anirban Sen / Reuters: Sources: Kalshi has probed and flagged 400+ suspicious trades YTD, more than 2x the number it investigated in all of 2025; Polymarket has seen a similar uptick — Top prediction market platforms Kalshi and Polymarket have witnessed a surge in suspicious trades this year …