Binance has filed a $470M lawsuit accusing crypto payment-card startup RedotPay of poaching its own users.

RedotPay, a Hong Kong card issuer, had integrated Binance Pay as a funding option. Binance's suit says it then improperly diverted those users to itself.

It is a rare public clash between Binance and a partner that plugged straight into its payment rails, turning on who really owns the customer in crypto payments.