Polymarket says it briefly halted trading over third-party security incident

Polymarket said it temporarily halted trading on Thursday, 29 October 2026, because of a security incident involving a third-party provider. The company said trading resumed later that day. It also said it would fully reimburse affected traders. The Guardian and Reuters both reported these statements. Both reports rely on Polymarket's own statements.

Details reported by The Guardian

According to The Guardian, the halt affected Polymarket's international platform. The newspaper reported that trading was paused for about an hour and resumed on Thursday afternoon. It did not specify a time zone.

The Guardian quoted Polymarket as saying it halted trading "out of an abundance of caution". According to The Guardian, Polymarket said in a post on X: "We’ll make this right and are fully reimbursing all affected traders". The newspaper also reported that Polymarket said affected traders "will be made whole". According to The Guardian, Polymarket said it referred the incident to a law enforcement agency in the United Kingdom.

Possible link to DebugBear

The Guardian reported that unnamed reports have linked the incident to DebugBear, a UK-based company that offers website performance-monitoring tools. The reports reviewed by Vocemundi do not show Polymarket naming the third-party provider. They do not include confirmation from either company that the two incidents are connected.

According to The Guardian, DebugBear said in a post 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. The newspaper reported that DebugBear's website was unavailable on Thursday afternoon. DebugBear did not immediately respond to a request for comment from The Guardian.

What each side says

• Polymarket: It halted trading as a precaution after identifying and fixing the issue affecting its international platform. It says anyone affected will be fully reimbursed.
• DebugBear: It was affected by an ongoing security incident. It says clients using one of its products should remove the embed code from their websites.

What remains unclear

According to The Guardian, it was not immediately clear to what extent traders were affected or how broad the impact was. The reports reviewed by Vocemundi do not say how many traders were affected, or how much money or how many assets were involved. They do not describe the nature of the incident. They do not identify which UK agency received the referral. They do not say whether any Polymarket platform other than the international one was affected. They do not describe how or when reimbursements will be made, and they do not give exact halt and resumption times.

Analysis

The episode shows how an online platform's operations can depend on outside software providers. If the reported link to DebugBear were confirmed, it could raise questions about how websites vet embedded third-party code. That link is not verified in the reports reviewed by Vocemundi. Polymarket's reimbursement pledge may limit direct losses for traders. However, its practical scope is unclear without details on how many people were affected and how payments will work. The UK referral could produce further information, or it could yield no public findings. Which scenario applies depends on disclosures not included in the reports so far.

Produced by the Vocemundi newsroom with AI assistance.