A cluster of Polymarket accounts won 41 of 42 bets on company earnings results, The Wall Street Journal reported on Friday. All 18 companies involved were audited by KPMG.
Bubblemaps, the blockchain data firm that supplied the numbers, traced 19 connected accounts with a 98% win rate on the KPMG names.
The bets began in November 2025 and ran for several months, returning roughly $22,000. Wells Fargo, DoorDash, General Mills and Home Depot were among the companies involved.
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Polymarket’s earnings markets resolve against a Wall Street consensus estimate fixed when each market opens. Traders buy yes or no shares on whether the reported figure clears it.
KPMG said it has “zero tolerance” for employees who use nonpublic client information, including on prediction markets. No KPMG employee has been charged.
The firm also advises the trading industry on these venues, telling brokers that prediction markets will not scale inside mainstream finance on narrative alone.
Traders Found the Same Pattern in February
On-chain researchers flagged the cluster seven months before the Journal did. In late February, posts on X and a Substack write-up listed wallet addresses betting heavily and almost only on KPMG-audited names.
Those included Home Depot, DoorDash, CarMax, Thor Industries and StoneX, and one researcher noted that the Wells Fargo market flipped the night before the results came out.
Polymarket rewrote its market integrity rules in March, banning trades on stolen confidential information, trades on illegal tips, and trades by anyone able to influence an outcome.
A spokesperson said Polymarket does not discuss specific law enforcement matters, adding that “we regularly refer matters to law enforcement and support ongoing investigations.”
Two Insider Cases Are Already in Court
Federal authorities have brought two criminal prediction market cases so far, the first of them against a US soldier, Gannon Ken Van Dyke, who was indicted in April over Polymarket trades tied to classified intelligence on Venezuela.
The Commodity Futures Trading Commission (CFTC) charged a Google software engineer in May over $1.2 million in bets on Google’s Year in Search list.
The Journal reported in late August that a KPMG employee and a US service member were targets of a further round of cases. Prosecutors in Manhattan and Washington had not made final charging decisions, and charges could come this fall.
Whether the account cluster described on Friday belongs to that employee has not been established.
Banks Started Rewriting These Policies in March
JPMorgan began reviewing whether its employee trading rules reach Kalshi and Polymarket in March, a review covering roughly 320,000 staff, according to Barron’s.
Attorneys at Debevoise & Plimpton said prediction markets “are not an insider trading safe zone,” naming employees, contractors, lawyers, bankers, consultants and board members among those exposed.
Partners Charu Chandrasekhar, Daniel Gitner and Douglas Zolkind said the theories the Justice Department and the CFTC have advanced reach past classified information, to confidential corporate data misused in breach of a duty.
Polymarket put its surveillance operation on display last month ahead of the US midterms. It described machine learning, blockchain tracing, open-source research and referrals to authorities, and said it had passed more than 100 cases to law enforcement.
The earnings contracts sit on Polymarket’s international platform, where trades settle on a public blockchain. Polymarket relaunched a CFTC-regulated US venue in December 2025.
