According to Polymarket, the prediction market platform has denied hacker claims regarding a purported data breach affecting over 300,000 records. The platform called the reports 'complete and utter nonsense' after a dark web actor using the handle 'xorcat' posted on DarkForums claiming to have pulled more than 300,000 records, including 10,000 user profiles with names, profile images and wallet addresses. The post was flagged by Dark Web Informer and cybersecurity firm Vecert Analyzer. Polymarket stated that the data sits behind public endpoints and on-chain records that any developer can pull for free, contradicting the hacker's claims of accessing undocumented API endpoints and exploiting CORS misconfiguration on Gamma and CLOB APIs.
As reported by Polymarket, the platform has published enhanced Market Integrity Rules and highlighted a multi-layered monitoring system on its Polygon-based DeFi venue, where all holders in each contract and their positions are publicly viewable. The enhanced monitoring system targets insider trading, fraud, and market manipulation through anomaly detection tuned to patterns consistent with insider knowledge in prediction markets. The platform states that because every trade, position, and settlement is recorded on a public blockchain, this transparency can now be harnessed to set a new public standard for market integrity in prediction markets. This comes as the platform has established a live bug bounty program that opened on April 16 and has logged 446 reports as of Wednesday, according to its Cantina listing, addressing claims that the platform runs no such program.
According to Polymarket, the integrity rollout follows record trading volumes that are driving the push toward institutional-grade surveillance and compliance. The platform set a new all-time daily volume record of about $425 million on February 28, surpassing its prior high from the 2024 U.S. election, while February's total volume topped $7 billion - roughly a 7.5x year-over-year jump. This explosive growth is happening against a backdrop of regulatory and compliance pressure, with recent analyses noting that by early 2026, platforms like Polymarket and Kalshi were outlining fresh insider trading controls as the broader sector scaled toward roughly $21 billion in monthly volume. The platform framed the enhanced monitoring as sending a clear signal that insider trading is not welcome on Polymarket, positioning it as a test case for what market integrity can look like in an on-chain world.
The integrity rollout follows Polymarket's April 28 exchange stack upgrade, described internally as its most significant overhaul to date. The upgrade introduced CTF Exchange V2 smart contracts, a rewritten central limit order book engine, and Polymarket USD (pUSD) as a new collateral token. According to Polymarket's documentation, pUSD is a standard ERC-20 token on Polygon, backed 1:1 by USDC, with the backing enforced onchain by the smart contract - no algorithmic peg, no fractional reserve. All trading still settles in native USDC to improve capital efficiency at the settlement layer, with the platform migrating off bridged USDC.e toward pUSD issued directly against Circle's USDC to cut failed trades, lower gas costs, and improve order management.
