South Korean exchange Bithumb won its first unjust enrichment lawsuit, with the court ordering a user who sold mistakenly issued Bitcoin to return the proceeds from the sale.

The incident occurred during a reward distribution event in February. Bithumb originally planned to issue rewards in Korean won but mistakenly credited 620,000 BTC units to a user's account due to a system error; this credited amount did not represent the actual Bitcoin held and deliverable by the exchange.

Upon discovering the error, the platform froze withdrawals and recovered 618,214 mistakenly credited BTC units before they were traded; the remaining 1,786 units had been sold by some users, prompting Bithumb to initiate recovery procedures against four users who did not return the sale proceeds.

On August 27, Judge Kim Yu-seong of the Seoul Central District Court ruled in the first instance, supporting Bithumb's claim for approximately 194 million won, equivalent to about $140,000, in unjust enrichment; this case is the second largest in terms of claim amount among four cases.

The other three cases have claims of approximately 500 million won, 14.8 million won, and 5 million won, totaling about 519.8 million won; this case is subject to first-instance judgment, while the other cases are still pending trial, and the relevant parties may still appeal according to the law.

From a market mechanism perspective, if orders sold from the mistakenly credited accounts enter the order book, it could expose the exchange to asset gaps, abnormal transactions, and counterparty settlement risks. Bithumb mitigated actual outflow by freezing withdrawals and subsequently sought to recover fiat proceeds from those who had sold; the pressure falls on users who exchanged the erroneously credited assets and retained the profits, while the beneficiaries are the exchange and regular customers, as recovery helps restore the platform's financial integrity and prevent losses from being socialized.

Source: Public Information