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Gaming Edge’s TL;DR
- A Bloomberg video report has put fresh attention on insider-trading concerns in prediction markets.
- A review found that thousands of Polymarket trades during 2025 and 2026 were flagged as possibly suspicious.
According to a Bloomberg video segment, a review found that at least 34,000 Polymarket trades between August 2025 and June 2026 were flagged as potentially suspicious.
Unusual betting activity across prediction markets also included a reported $200 million surge in suspicious bets.
Bloomberg cross-asset reporter Denista Tsekova said the activity often showed patterns such as precise timing, short-lived wallets, and unusually high accuracy. One example cited in the report involved 38 connected wallets with 100% accuracy.
Polymarket has made changes
The report frames the issue as a market-integrity problem for a fast-growing corner of gambling-adjacent trading. It also notes that platforms and regulators are trying to identify suspicious activity as prediction markets become more prominent.
Tsekova said Polymarket has changed its approach over time, stating that “the market has changed their opinion a lot on what constitutes insider trading.” The transcript says Polymarket put formal insider-trading rules in place in March and has been more thorough since then.
The segment also points to US oversight. It says the CFTC has a large team tracking these cases, and that some matters have already led to investigations and prosecutions. Examples mentioned in the transcript include a Google engineer case and a case involving alleged trading tied to Venezuela-related outcomes.
For players and market users, the main takeaway is not that every flagged trade was proven misconduct. The review described the trades as potential insider trading, and the source does not say how many were ultimately confirmed.
Still, the report suggests integrity enforcement is becoming a bigger issue for major prediction market operators, including Polymarket and Kalshi.
Based on reporting by Bloomberg Podcasts.
