Polymarket, a prominent prediction market platform, temporarily suspended trading on its international platform on Thursday after a security incident compromised a third-party provider, the company confirmed. Trading was paused for approximately one hour before resuming in the afternoon, with Polymarket committing to fully reimburse affected traders.
The company stated it halted operations out of an abundance of caution after identifying and addressing the issue. In a post on X (formerly Twitter), Polymarket said: ‘We’ll make this right and are fully reimbursing all affected traders.’ The company also reported the incident to law enforcement in the United Kingdom.
Polymarket did not specify the exact number of users impacted but reiterated that anyone affected would be ‘made whole.’ Reports from users on Polymarket’s Discord channel suggested some wallets had been drained, though the company did not confirm financial losses. Crypto news outlet The Block, citing blockchain analysis group Arkham, reported that approximately $2.65 million in cryptocurrencies had been siphoned from the platform.
The breach was linked to DebugBear, a UK-based company providing website performance monitoring tools. DebugBear’s own website became unavailable on Thursday, and the company posted on X that it was ‘impacted by an ongoing security incident.’ It advised clients using one of its products to remove the embed code from their websites but did not immediately respond to requests for comment.
Polymarket’s U.S.-based platform remained unaffected by the incident, according to the company. The platform, which has faced regulatory scrutiny in the U.S., was valued at $21 billion in September 2023 following a $1 billion investment led by Donald Trump Jr. Earlier on Thursday, Bloomberg News reported Polymarket was under investigation for potential insider trading threats.
Prediction markets like Polymarket and rival Kalshi have become central to a broader debate over regulation, with U.S. states and the Trump administration clashing over jurisdiction. The platforms have also faced challenges related to market integrity and compliance with financial regulations.