Bitbank blocks accounts for transactions with Polymarket: tightening compliance in Japan
Japanese crypto exchange Bitbank has officially notified clients of the possibility of account suspension upon detecting transfers related to prediction market platforms, particularly Polymarket. This decision is not a response to a direct regulatory directive, but a preventive internal compliance measure aimed at adhering to local gambling laws.
According to Bitbank's statement from June 15, prediction markets, which allow trading on event outcomes (from elections to sports matches), pose legal risks for users in Japan. Even if such services operate outside the country, accessing them for financial gain may be considered a violation of the law. As a specific example, the exchange directly cited Polymarket and similar betting platforms.
What users face
If Bitbank confirms the deposit or withdrawal of funds from such services, the account will be completely blocked. This means losing access to all functions: logging in, trading crypto assets, depositing and withdrawing funds, as well as withdrawing Japanese yen. Notably, the exchange disclaims any responsibility for potential losses incurred by clients due to such blocks.
Polymarket's stance and global context
In Polymarket's documentation, Japan is already listed as a jurisdiction with restricted access to the user interface. However, the restriction applies only to the website, not the API, leaving a loophole for technically savvy users. Previously, according to insiders, Polymarket explored the possibility of entering the Japanese market, but strict local regulations on online betting make this task extremely challenging.
Bitbank's warning is just part of a global trend. Earlier in 2026, the Portuguese regulator demanded that Polymarket cease operations after the volume of bets on local elections exceeded €103 million. Spain temporarily blocked the platform due to a lack of a gambling license, and Indonesia imposed a complete ban. Against this backdrop, Japan is taking a preventive approach, forcing local operators to tighten controls on their own.
Analytical conclusion
This move by Bitbank is a signal to the entire market: regulatory pressure on decentralized prediction markets is growing exponentially. Users, especially in countries with strict gambling laws, should reconsider their strategies. The risk of having an account blocked on a centralized exchange due to a transaction with Polymarket is not a hypothetical threat but a working compliance mechanism that will only become stricter.