Kalshi and Polymarket trading volumes face scrutiny amid rapid growth

Trading activity on some Kalshi and Polymarket products is drawing scrutiny from industry observers who say the numbers may be inflated or distorted. The concerns center on unusual volume patterns in Polymarket’s international exchange and on Kalshi’s ether perpetual futures contract, though both companies deny that wash trading is taking place. On Polymarket, observers pointed to markets where lowerprobability contracts attracted more trading than higherprobability ones, including in elections, sports, and central bankrelated markets. On Kalshi, CNBC and outside analysts noted a concentration of trades near a specific dollar amount on its ether perpetuals, along with a high ratio of reported volume to resting liquidity. The questions matter because both companies have used rising trading volumes to support claims of growth as they seek higher privatemarket valuations and consider possible public listings. Some experts said the activity could reflect market incentives, arbitrage, or the behavior of active traders rather than clear manipulation, but they also warned that the patterns can make liquidity and demand look stronger than they are. Regulators and market structure experts said exchanges have a responsibility to monitor unusual activity, while Kalshi and Polymarket said they have controls in place and reject claims of inorganic trading. CNBC reported that the CFTC is also examining trades on Kalshi’s ether perpetual contract, although the agency has not confirmed any investigation.