South Korea Probes 26 Polymarket Users Over $12.7M Bets

South Korean police have opened criminal cases against 26 Polymarket users over alleged illegal gambling, with 18 of those cases already referred to prosecutors, according to Asia Economy and information shared by Wu Blockchain.

The users allegedly placed bets totaling 17.6 billion won, equivalent to $12.7 million. Police reportedly identified participants using publicly available blockchain transaction records alongside open-source intelligence, or OSINT.

Police Identify Polymarket Users Through Blockchain Records

According to the report, investigators traced activity connected to Polymarket through public blockchain data and combined those records with other publicly available information to identify individuals in South Korea.

One person allegedly accounted for as much as 5.7 billion won in wagers, representing a substantial portion of the total amount under investigation.

The cases concern allegations that the users participated in illegal gambling through Polymarket. The investigation has already moved beyond the initial police stage for 18 individuals, who have been referred to prosecutors, according to Asia Economy.

The figures cited in the report concern alleged wagering activity and do not establish that every transaction or participant resulted in a criminal conviction.

South Korea Had Blocked Polymarket Access

The investigation follows South Korea's decision to block access to Polymarket, described as the world's largest prediction-market platform, on Aug. 18.

Polymarket allows users to trade contracts linked to the outcomes of events. Its markets have covered areas including politics, economics, sports and other real-world events. In South Korea, authorities have taken action against access to the platform amid concerns surrounding its use for betting.

The latest police investigation demonstrates that restricting direct access to a platform does not necessarily eliminate the ability of investigators to examine related activity. Blockchain transactions can remain publicly visible even when access to a particular website or service is restricted.

Blockchain and OSINT Used in Investigation

The reported investigation also highlights the role of publicly available digital information in identifying users of blockchain-based platforms.

Unlike traditional financial transactions that may require access to records held by financial institutions, many blockchain transactions can be examined directly through public ledgers. Investigators can then combine wallet activity with information available elsewhere to establish potential links to individuals.

In this case, South Korean police reportedly used blockchain records together with OSINT to identify Polymarket users suspected of participating in the alleged illegal betting activity.

The investigation involves 26 users in total, while 18 cases have already been sent to prosecutors. The remaining cases remain at the police investigation stage based on the information reported by Asia Economy.

Cases Move Toward Prosecutorial Review

The referral of 18 individuals to prosecutors markets the next stage of the reported criminal proceedings. Prosecutors will assess the cases under applicable South Korean law.

The reported wagering total stands at 17.6 billion won, or $12.7 million, while the largest individual amount cited by police is 5.7 billion won.

Writer: Victoria Hale
Technology & Blockchain Writer

Victoria Hale writes about blockchain technology, digital infrastructure, and the intersection of emerging technologies with finance. Her articles explore how new protocols and systems are shaping the evolving digital economy.

She prioritises clarity and accuracy when explaining technical developments to a general audience.