Polymarket pauses international trading for about an hour after vendor security breach

A pause of about an hour

Polymarket halted trading on its international platform for roughly an hour on 29 October, after a security incident compromised a third-party provider. Trading resumed that afternoon. Wired described the pause as lasting several hours, although other reports put it at about an hour. The company said it paused trading "out of an abundance of caution" once it had identified and fixed the problem. Some users reported that their accounts had been drained shortly before the stoppage, and Polymarket said it had referred the incident to a law enforcement agency in the United Kingdom.

How the incident unfolded

Users in Polymarket's official Discord began to panic around 1:30 p.m. after reports that some wallets had been emptied. Around 2 p.m., the platform moved into cancel-only mode, which lets traders cancel pending transactions but blocks new orders. After trading resumed, Polymarket posted on X to say that affected traders would be made whole.

“We'll make this right and are fully reimbursing all affected traders.”

The vendor at the centre of the breach

Reports linked the incident to DebugBear, a UK-based company that sells website performance monitoring tools. A person familiar with the matter, who spoke on condition of anonymity, told the Washington Post that the issue involved DebugBear, which describes its product as a performance and debugging platform. DebugBear's own website was unavailable on the afternoon of 29 October, and the company said on social media that it was affected by an ongoing security incident. It asked clients using one of its embedded web-monitoring tools to remove the code from their sites. DebugBear did not immediately respond to requests for comment. Wired reported that the breach hit the vendor rather than Polymarket's own website, and that Polymarket US, the separate platform for people in the United States, was not affected.

Scale of losses still unclear

It is not yet clear how many traders were hit or how much money was lost. Blockchain analytics firm Bubblemaps put the number of affected users at around 700 and the stolen amount at approximately $2.7 million. Wired reported that Polymarket declined to comment on those figures when asked, but said impacted traders will be refunded. Prominent traders complained on X that they had lost money during the disruption.

Earlier breaches and insider-trading cases

Wired reported that Polymarket had suffered another breach in June 2026, which caused more than $2 million in losses for affected traders. The platform, launched in 2020, has also been at the centre of several high-profile alleged insider trading cases, some of which led to arrests. One involved a special forces soldier accused of betting on the capture of Venezuela's former leader. Another involved a Google employee who allegedly used confidential information to make millions. In both cases the suspects have pleaded not guilty.

Funding and structure

In August 2026, Polymarket raised $1 billion in a round led by 1789 Capital, a venture capital firm where Donald Trump Jr. is a partner. The company is valued at $21 billion. Its markets cover everything from the midterm elections to the release date of Grand Theft Auto VI. Polymarket runs two separate platforms: the international one is a cryptocurrency-based platform banned in the United States and several other countries, while Polymarket US operates as a federally regulated financial exchange within the country.