The complaint says BitMEX designed a system to retain customer collateral and alleges an internal desk accessed private user data during server freezes.

The platform, co-founded by Arthur Hayes, has notified users they have until Sept. 23 to withdraw their assets or face penalty charges.

BitMEX faces a proposed class action alleging it engineered customer liquidations and seized nearly 623 BTC, filed the day BitMEX announced its shutdown.