- Recent investigations show that Polymarket’s trades are being counted twice on most public dashboards.
- The issue arises from redundant maker-taker events emitted by the smart contracts.
- According to the findings, actual volumes may be roughly half of what dashboards report.
Polymarket, a leading prediction market platform, has come under scrutiny after an analysis by Storm Slivkoff suggested that the trading volumes reported by the platform may be systematically overstated across most public analytics dashboards.
The controversy has attracted attention from industry experts, data analysts, and market participants, raising questions about how trading activity is measured and reported on decentralized prediction markets.
Polymarket emits separate OrderFilled events for makers and takers
Storm Slivkoff, a partner at Paradigm, identified a technical discrepancy in Polymarket’s on-chain smart contract data. Slivkoff’s findings — later highlighted by cofounder Matt Huang — point to the platform emitting separate OrderFilled events for both the maker and taker sides of each trade.
While each individual event is accurate, most public dashboards aggregate all events indiscriminately, effectively double-counting the same trade.
found a pretty major data bug
it turns out almost every major dashboard has been double-counting Polymarket volume (not related to wash trading)
this is because Polymarket’s onchain data contains redundant representations of each trade. receipts ⬇️⬇️ pic.twitter.com/rQJEzs2Rfl
— storm (@notnotstorm) December 8, 2025
A simple transaction demonstrates the problem. A trade of YES tokens for $4.13 produced two identical events for the same amount, which dashboards summed to report $8.26 in trading volume.
Slivkoff pointed out that this bug affects both notional contract volume (the number of contracts traded) and cash-flow volume (the dollar value exchanged), inflating the representation of each trade.
Importantly, the discrepancy is not related to wash trading; it arises solely from how Polymarket’s contracts emit event data.
Polymarket disputes the double-counting claims
Polymarket’s internal team responded quickly to the accusations, stating that the official site reports collector-pool volume without double-counting, following standard industry practice.
The platform emphasized that the issue mainly affects third-party dashboards that rely on raw contract event feeds without applying deduplication logic for redundant entries.
Notably, several major data providers, including DefiLlama, Allium Labs, and Blockworks, confirmed they are updating their dashboards to account for the discrepancy.
Some data providers defended their existing methodologies, noting that more sophisticated dashboards have already handled this distinction since 2024, although they have not formally documented their approach.
Other providers criticized Paradigm for potential bias, pointing out that the firm holds investments in Kalshi, a U.S.-based competing prediction market.
Broader implications for the market
Beyond the immediate question of reported volume, the controversy highlights wider challenges in accurately measuring activity on prediction market platforms.
Low-priced contracts can produce disproportionately large notional volumes relative to the actual capital at risk, which may make traditional volume metrics misleading.
Experts have suggested that metrics such as open interest and fee revenue can provide a clearer picture of platform activity.
The timing of the revelation is also notable, coinciding with Polymarket’s plans for a full relaunch in the United States following CFTC regulatory approval and a potential valuation in the $12–15 billion range.
The platform is also exploring an internal market-making operation that could trade against customers, further increasing scrutiny and comparisons with competitors like Kalshi.