After virtual asset exchange Bithumb paid 620,000 bitcoins to 249 event winners, it treated 1,788 of them as "normal" transactions during the cleanup and bought them externally to balance the quantity. Bithumb had planned to pay each winner 20,000 to 50,000 won, but an employee mistakenly entered "bitcoin" instead of "won." The 620,000 bitcoins amount to about 62 trillion won.
According to the virtual asset industry on the 9th, Bithumb paid 620,000 bitcoins to 249 event winners at 7 p.m. on the 6th. After recognizing the mispayment, Bithumb corrected the ledger by canceling the payment of 618,212 (99.7%).
The remaining 1,788 were transacted before the payment cancellation. Some customers tried to cash out by selling the mispaid bitcoins and attempted withdrawals, and some reportedly transferred the bitcoins to overseas exchanges. Bithumb recognized these as official transactions and belatedly purchased 1,788 externally to match the quantity. Bithumb plans to recover the bitcoins by obtaining consent from the traders to cancel the transactions.
Virtual asset exchanges like Bithumb conduct ledger transactions similar to banks or securities. Virtual assets are traded frequently, and since the physical asset cannot be exchanged each time a transaction occurs, the transaction history is recorded and later reflected in the ledger.
For example, when a bitcoin transaction is executed, it is recorded only in the ledger and the bitcoin does not move. Spot bitcoins are stored in Bithumb's wallet. A transaction in which ownership of the bitcoins held by Bithumb changes is recorded on the Blockchain. Bitcoins are withdrawn only when a customer requests that the purchased bitcoins be sent to a personal wallet. Through payment and settlement procedures, Bithumb must verify that the numbers on the ledger match the assets held.
If Bithumb had not purchased 1,788 bitcoins externally to match the quantity, it would mean that "ghost bitcoins" that do not exist were transacted.
Bithumb depositing 620,000 bitcoins into customer accounts amounts to a promise to pay 620,000 bitcoins; it does not mean bitcoins were created out of thin air. As Bithumb recorded the payment in the ledger, the system showed it as if payment had been made to customer accounts.
In the virtual asset industry, it is presumed that Bithumb either lacked even basic internal control systems or had a technical issue. Bithumb holds about 46,000 bitcoins (including client-entrusted amounts), yet there were no restrictions on paying out more than that. A Bithumb official said, "It is difficult to disclose the cause of the mispayment because the financial authorities are investigating."