South Korean cryptocurrency exchange Coinone has filed a lawsuit against the Financial Intelligence Unit (FIU) seeking to overturn a partial business suspension and halt its enforcement. The FIU had previously fined Coinone 5.2 billion won for violations of the Specific Financial Information Act, citing issues related to transactions with unregistered operators, KYC, and transaction restrictions. Following Coinone's legal action, major South Korean exchanges including Upbit and Bithumb have also entered legal disputes concerning FIU sanctions.