- Recent research indicates that trades on Polymarket are being counted twice on most public dashboards.
- The issue stems from redundant maker-taker events emitted by the platform’s smart contracts.
- As a result, actual volumes may be roughly half of what many dashboards report.
Polymarket, a leading prediction market platform, has come under scrutiny after research by Storm Slivkoff suggested that reported trading volumes may be systematically overstated across many public analytics dashboards.
The controversy has drawn 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, published research — later highlighted by Paradigm cofounder Matt Huang — revealing a technical inconsistency in Polymarket’s on-chain smart contract data.
According to Slivkoff, the platform emits distinct OrderFilled events for both the maker and the taker in each trade.
While each event is individually accurate, most public dashboards aggregate all events without differentiating between them, effectively counting the same trade twice.
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
One simple transaction illustrates the problem. A single trade swapping YES tokens for $4.13 produced two identical events for the same amount. Dashboards summing both events reported a trading volume of $8.26.
Slivkoff noted that this bug affects both nominal volume (number of contracts traded) and value volume (dollar value exchanged), inflating the representation of each trade.
Importantly, the issue is not related to wash trading; it arises solely from how Polymarket’s contracts emit event data.
Polymarket disputes the double-counting allegation
Polymarket’s internal team quickly rejected the accusation, stating that the official site reports volume from the taker side only and does not double-count, which aligns with standard industry practices.
The platform emphasized that the issue primarily affects third-party dashboards that rely on raw smart contract event data without applying corrections for redundant records.
Notably, several major data providers, including DefiLlama, Allium Labs, and Blockworks, confirmed they are updating their dashboards to account for this discrepancy.
Some data providers defended their current methodologies, arguing that more sophisticated dashboards have accounted for this distinction since 2024, although they had not formally documented their approaches.
Other providers criticized Paradigm for potential bias, noting Paradigm’s investments in Kalshi, a competing U.S. prediction market.
Wider market implications
Beyond the immediate question of reported volume, the controversy highlights broader challenges in accurately measuring activity on prediction market platforms.
Low-cost contracts can produce disproportionately large theoretical volumes relative to actual at-risk capital, making conventional volume-based metrics potentially misleading.
Experts suggest that alternative metrics such as open interest and fee revenue may provide a clearer picture of platform activity.
The timing of the revelation is notable: it coincides with Polymarket’s plans for a full relaunch in the U.S. following CFTC regulatory approval and an anticipated valuation in the $12–15 billion range.
The platform is also investigating an internal market operation that may have traded against customers, further increasing scrutiny and comparisons with competitors like Kalshi.