- Recent research shows that most publicly available dashboards have been double-counting a large portion of Polymarket’s trades.
- The issue stems from redundant maker-taker events emitted by the smart contracts.
- According to the allegation, the true call volume is roughly half of what dashboards report.
Polymarket, the well-known prediction market platform, has come under scrutiny after research by Storm Slivkoff indicated that the trading volume reported on many public analytic dashboards may be systematically overstated.
The controversy has drawn attention from industry experts, data analysts, and market participants, raising questions about how trading activity should be measured and reported in decentralized prediction markets.
Polymarket emits separate OrderFilled events for makers and takers
Research by Paradigm partner Storm Slivkoff, later highlighted by Paradigm co-founder Matt Huang, found a technical discrepancy in Polymarket’s on-chain smart contract data.
Slivkoff reported that the platform emits an OrderFilled event for both the order maker and the order taker for each trade.
While each event is accurate in itself, most public dashboards aggregate all events without distinguishing their roles, 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
A single example illustrates the problem: a YES token trade for $4.13 generated two identical events for the same amount, leading dashboards to report a combined volume of $8.26.
Slivkoff noted that the bug affects both nominal trade volume (contract counts) and cash flow (the dollar value exchanged), inflating the representation of each trade.
Importantly, this error is not related to wash trading; it is caused purely by the way Polymarket’s contracts output event data.
Polymarket disputes the double-counting claim
Polymarket’s internal team quickly rebutted the allegation, stating that the official website does not double-count maker or taker volumes when reporting, and that this approach conforms with industry practice.
The platform emphasized that the issue mainly impacts third-party dashboards that rely on raw contract event data without correcting for redundant entries.
Notably, several major data providers, including DefiLlama, Allium Labs, and Blockworks, have confirmed they are updating dashboards to account for the discrepancy.
Some providers defended their prior methods, saying that since 2024 more sophisticated dashboards have distinguished maker and taker events, though those practices were not always formally documented.
Other data vendors criticized Paradigm as potentially biased, pointing out the firm’s investment in the U.S. competitor Kalshi.
Broader market implications
Beyond the immediate reporting discrepancy, the debate highlights broader challenges in accurately measuring activity on prediction market platforms.
Low-price contracts can produce nominal trading volume that is large relative to actual capital at risk, so conventional volume metrics may be misleading.
Experts suggest alternative indicators — such as open interest, number of settled contracts, and fee revenue — may better reflect true platform activity.
The timing of this disclosure is notable: Polymarket is preparing a full relaunch in the U.S. following CFTC regulatory clearance, with reported valuation expectations in the $12 billion to $15 billion range.
The platform is also exploring internal market-making operations that could involve trading with customers, inviting further comparison and scrutiny against competitors like Kalshi.