Japanese crypto exchange Bitbank has warned customers that accounts connected to prediction market platforms such as Polymarket could face suspension.
- Bitbank warned that accounts linked to Polymarket and other prediction market platforms could be suspended under its compliance policies.
- The exchange said users may lose access to trading, withdrawals, and account functions if transfers to prediction market services are detected.
- The warning comes as Polymarket faces growing scrutiny from regulators and law enforcement agencies in Japan, South Korea, and the U.S.
According to a notice published by Japanese cryptocurrency exchange Bitbank, users who deposit to or withdraw from prediction market services may be subject to account restrictions if the activity is linked to platforms that could be considered gambling under Japanese law.
The exchange said prediction markets allow users to trade on the outcome of future events, including elections, sporting events, and other real-world developments using cryptocurrencies. While many of these platforms are operated overseas, Bitbank stated that accessing and using them from Japan for financial gain could potentially fall under gambling-related offenses.
Under the policy outlined by the exchange, accounts found to have transferred funds to prediction market services or related platforms may be suspended. Bitbank said affected users would lose access to account logins, cryptocurrency deposits and withdrawals, yen withdrawals, and trading functions.
The exchange also stated that it would not be responsible for losses resulting from account suspension measures. Users who believe their accounts were restricted in error have been directed to contact the company through its support channels for a review.
Japan joins growing list of jurisdictions scrutinizing prediction markets
Bitbank’s warning arrives as prediction market platforms continue drawing attention from regulators and law enforcement agencies across multiple countries.
Back in May, Polymarket clarified that it was not introducing mandatory identity verification requirements across its main platform after reports suggested stronger compliance measures were under consideration. At the time, Polymarket vice president of engineering Josh Stevens said KYC checks applied only to a limited beta product and would not become a requirement for existing users on polymarket.com.
Polymarket continues to list Japan among jurisdictions subject to frontend restrictions, while several other countries remain blocked or limited to close-only trading activity because of regulatory obligations and compliance requirements.
Outside Japan, authorities in South Korea have already moved beyond compliance concerns and opened the country’s first known investigation into domestic Polymarket users. The Gangwon Provincial Police Agency is examining whether participation on the platform violated local gambling laws after a request from the national police headquarters.
Attorney Ahn Chang-bo, who represents some of the users under investigation, told Chosun Biz that the legal elements required for a gambling offense appear to be present, although he noted that no domestic precedent currently exists involving punishment for Polymarket users.
Regulatory attention has also intensified in the United States, where federal authorities have pursued several cases tied to activity on prediction markets.
Most recently, a Manhattan court scheduled a Dec. 7 trial for Army soldier Gannon Van Dyke, who prosecutors accuse of using classified military intelligence linked to an operation involving Venezuelan President Nicolás Maduro to place profitable wagers on Polymarket. Federal prosecutors allege Van Dyke turned roughly $33,000 into more than $410,000 through a series of event-based trades before attempting to conceal the activity.
Separate from that criminal case, the Commodity Futures Trading Commission has continued emphasizing that fraud, manipulation, and insider trading rules apply to prediction markets operating under its jurisdiction.
Questions surrounding Polymarket’s operations have extended beyond trading activity. Earlier this month, a POLITICO investigation reported that the platform paid at least $350,000 to social media influencers over a 14-month period, with many promotional posts allegedly appearing without disclosures identifying paid relationships.
