Bithumb Wins First-Instance Rulings to Recover Proceeds From $40B Fat-Finger Error

A South Korean court has sided with Bithumb in two separate lawsuits the exchange brought against users who sold Bitcoin that was mistakenly credited to their accounts earlier this year, setting a potentially significant legal precedent for how fat-finger errors are adjudicated in Korean jurisdiction.

The error occurred in February 2026, when a system fault caused Bithumb to internally credit 620,000 BTC to hundreds of users. At prevailing prices, that represented somewhere between $40 billion and $43 billion worth of Bitcoin, implying a price range of roughly $64,500 to $69,350 per coin at the time. Some of those users liquidated their windfall before Bithumb could claw it back. The exchange went to court seeking to recover the proceeds from those sales, and this week it won first-instance rulings in both cases.

The legal question at the center of these suits is deceptively simple: when an exchange makes a catastrophic clerical error, who bears the loss? Bithumb's position is that users who sold Bitcoin they knew, or should have known, was not legitimately theirs are obligated to return the proceeds. The courts, at least at this stage, agreed. That outcome matters beyond Bithumb itself. South Korean courts have now signaled that exchange errors do not automatically transfer liability from the platform to the institution, and that users who act on obviously erroneous credits can be compelled to disgorge gains.

Consumer advocates and affected users can reasonably contend that retail participants should not be penalized for failures in exchange infrastructure they have no control over. A user who sees a balance, sells it, and spends the proceeds may be genuinely unable to repay. There is also the question of good faith: if someone received an unexpected credit and had no way to distinguish it from a legitimate deposit, the moral case for recovery weakens considerably. These arguments may carry more weight on appeal. First-instance rulings in South Korea are not final, and the affected users retain the right to escalate to higher courts, where the outcome could shift.

At $40 billion-plus, this stands as one of the largest documented exchange errors in the history of crypto markets. For context, the most notorious fat-finger incidents have typically involved trading systems sending orders at wildly wrong prices, not exchanges directly crediting billions in assets to retail accounts. The scale here is categorically different, which is precisely why the legal resolution carries weight. South Korea is home to some of the world's highest per-capita crypto trading volumes, and regulatory clarity around exchange liability is a live question across multiple jurisdictions globally. A durable ruling here could inform how other markets approach similar disputes.

What remains unanswered is whether Bithumb itself faces any regulatory or civil accountability for the error. Crediting 620,000 BTC to the wrong accounts is not a minor configuration issue. It points to a system control failure of extraordinary magnitude, and Korean financial regulators have not publicly addressed whether the exchange will face sanctions or be required to implement specific safeguards. Recovering funds from users resolves Bithumb's immediate balance sheet problem. It does not resolve the question of how 620,000 BTC ended up in the wrong hands in the first place.

For the broader industry, the ruling reinforces a principle that most exchanges already assert in their terms of service: erroneous credits are not gifts, and users who treat them as such take on legal risk. Whether that principle holds through appeal, and whether it migrates into other jurisdictions, will determine how lasting this week's decision actually proves to be.