← All newsPrediction Markets

Kalshi and Polymarket Under Review Regarding Trading Activity

Two prominent prediction market platforms, Kalshi and Polymarket, are reportedly facing scrutiny concerning unusual trading volumes observed on their respective sites.

PredictionSites Newsroom · 30 September 2026

Prediction market platforms Kalshi and Polymarket are reportedly attracting attention over certain trading patterns. The platforms, which allow users to bet on the outcome of future events, are understood to be under review due to what has been described as 'odd volume' in some markets.

Prediction markets operate by enabling participants to buy and sell contracts whose value is tied to a specific future event. The price of these contracts, typically ranging from 0 to 100 cents, can be interpreted as a crowd-sourced probability of that event occurring. When a contract settles at 100 cents (if the event happens) or 0 cents (if it doesn't), profits or losses are distributed.

While the precise nature of the 'odd volume' remains unspecified, such scrutiny often arises when trading activity deviates from expected norms, potentially signalling unusual market dynamics or behaviours. This could relate to significant, unexplained shifts in contract prices, unusually high liquidity in niche markets, or other irregularities that warrant closer examination.

Both Kalshi, which is regulated by the CFTC for event contracts, and Polymarket, a decentralised prediction market, facilitate trading on a diverse range of topics, from economic indicators to political outcomes. Reviews into trading activity are a common part of maintaining market integrity across various financial sectors, ensuring transparency and fairness for all participants.

Reported first by Briefs Finance — read the original report. This article was written by the PredictionSites newsroom from that report.