Japanese crypto exchange Bitbank has warned its users that trading on the prediction market platform Polymarket could result in account suspensions. The warning, issued this week, raises fresh questions about how Japanese gambling laws apply to crypto-based prediction markets — and whether users face legal risks for engaging with them.
What the warning says
Bitbank didn't mince words. In a notice posted to its platform, the exchange said participating in Polymarket may violate local regulations. Users who engage with the platform, Bitbank warned, risk having their accounts suspended or restricted. The exchange didn't specify a cutoff date or list specific bets that triggered the alert — just a blanket caution against any Polymarket activity.
Japan's gambling law question
The core issue is straightforward: Japan's criminal code bans most forms of gambling, but it's never been entirely clear whether prediction markets fall under that ban. Polymarket lets users place bets on everything from election outcomes to sports results using cryptocurrency. Japanese authorities have taken a hard line on unlicensed gambling in the past — but prediction markets operate in a gray zone. Bitbank's warning suggests the exchange sees real legal exposure for itself and its users.
What users should watch for
For now, Bitbank account holders who have used Polymarket should expect heightened scrutiny. The exchange didn't say whether it's actively scanning wallets or relying on self-reporting. But the message is clear: if you've traded on Polymarket, you could lose access to your Bitbank account. That's a painful prospect for anyone who uses the exchange for regular crypto trading or storage.
What comes next
Bitbank's move could put pressure on other Japanese exchanges to issue similar warnings — or on regulators to step in with clearer guidance. The Financial Services Agency hasn't publicly commented on Polymarket or prediction markets more broadly. Until it does, users are left weighing the convenience of these platforms against the risk of losing their exchange accounts.
