Polymarket is widening its partnership with Solidus Labs to deploy the HALO surveillance system to detect market manipulation and insider trading, after Solidus' April 29, 2026 report "Polymarket Under the Polygraph" flagged wash trading and found that fewer than 1% of wallets in key political markets captured about 50% of profits between December 2025 and February 2026. The move comes as prediction-market infrastructure expands more broadly: Kalshi partnered with Solidus in February 2026, Polymarket worked with Palantir and TWG AI around March 10, 2026 on sports-market surveillance, and third-party products such as PredictionBubbles, ProCap Insights and Polymarket's own APIs and WebSocket feeds are packaging market data from Polymarket and Kalshi for easier discovery and analysis. Unreviewed research cited around Kalshi sports contracts, parlay pricing and Polymarket's five-minute Bitcoin markets suggests contract prices can diverge from clean probability signals, especially near settlement, underscoring the growing importance of surveillance, distribution and interpretation tools.