Polymarket has resumed trading on its flagship international prediction-market platform after a hack at a UK-based third-party vendor drained funds from some users’ wallets. Blockchain analysts estimate that about 700 users were affected and roughly $2.7 million was stolen, while Polymarket says it will refund affected traders.
Third-party vendor linked to breach
Polymarket said the prediction-market website itself was not compromised. Instead, the incident involved a third-party vendor based in the UK. The company said UK law enforcement agencies had been notified.
Trading was initially paused while Polymarket investigated the incident for several hours. The company later announced that trading had resumed.
Several prominent traders reported losses on X. Blockchain analysis firm Bubblemaps reported that approximately 700 users were affected and that approximately $2.7 million was believed to have been stolen.
When WIRED asked Polymarket how many traders were affected and how much they had lost, the company declined to comment. It did say, however, that it would provide refunds to affected traders.
Polymarket US was not affected
The hack did not affect users of Polymarket US, the company’s newer platform for people in the United States. Polymarket operates two separate prediction markets.
Polymarket US functions as a federally regulated financial exchange in the United States. Its flagship international platform is cryptocurrency-based and is banned in the United States and many other countries.
Previous security and controversy concerns
This is not the first security issue to affect Polymarket traders. In June 2026, traders experienced another incident in which affected users suffered losses of more than $2 million.
Polymarket has also faced controversy since it was founded in 2020. In recent years, the platform has been at the center of several high-profile alleged insider-trading scandals that led to arrests.
One case involved a special forces soldier accused of betting on the capture of a former Venezuelan leader. Another involved a Google employee who allegedly made millions of dollars using confidential information. The suspects in both cases have maintained their innocence.
Company valued at $21 billion
In August 2026, Polymarket raised $1 billion in a funding round led by venture capital firm 1789 Capital, where Donald Trump Jr. is a partner. The funding round valued the company at $21 billion.
Source: www.wired.com