Bithumb wins first court ruling in South Korea over mistaken bitcoin payout from February event

Bithumb has won the first trial-court ruling in a set of lawsuits seeking to recover sales proceeds from users who sold bitcoin that was mistakenly paid out during a customer event in February. For exchanges and PSPs, the case is a clean reminder that payout errors do not end when the ledger is corrected; if the asset has already been sold, recovery turns into a civil claim.

1. On 27 August 2026, Kim Yu-seong, a single-judge civil panel of the Seoul Central District Court (Civil 90), ruled in favor of Bithumb in its unjust enrichment claim against a user identified as A. The amount in dispute was 1.94000443 billion won.
2. The court case proceeded by public service of process, which the Seoul Central District Court used because the defendant’s address or workplace was unknown and ordinary service of litigation documents was difficult. In other words: the defendant was not being served in the usual way, so the court treated notice as delivered through posting or similar methods.
3. The dispute traces back to 6 February, when Bithumb mistakenly paid compensation in bitcoin instead of won during a customer event reward process. The total mispaid bitcoin was 620,000. According to financial authorities, Bithumb blocked transactions and withdrawals after noticing the error and recovered 618,214 before any transaction took place; it then pursued separate recovery procedures for the remaining 1,786 that had already been sold.
4. Bithumb filed separate lawsuits in March against four users who sold the mistakenly paid bitcoin and did not return the proceeds. The case decided on 27 August is the second-largest claim among the four, after a case of about 500 million won; the other two claims are about 14.8 million won and 5 million won.
5. Two of the remaining cases are set for first hearings between the end of this month and early next month, while one still has no hearing date. The court also noted that the remaining suits may turn on different defenses and facts, so this ruling does not automatically decide the others.

For the industry, the more interesting part is what came after the payout error. In April, the Financial Services Commission required exchanges to maintain a continuous balance reconciliation system that compares user ledgers with actual crypto holdings every five minutes, and proposed automated verification plus multi-level approval for manually handled transactions such as event rewards. It also moved compliance oversight and risk management standards closer to the level used for financial companies.