Verify a decision

{"actor":"system:backfill","investigation_id":"29b9a461-3727-4b10-821f-f43a6c59a9da","kind":"publish","page_slug":"bithumb","published_at":"2026-10-22T04:12:50.781Z","sequence_num":1,"snapshot":{"content_type":"investigation","entity_name":"Bithumb","sections":[{"content":"In early February 2026, a Bithumb employee processing a promotional payout entered the reward amount in bitcoin (BTC) instead of Korean won (KRW), causing roughly 620,000 won worth of intended rewards to instead be credited as 620,000 BTC — worth over $40 billion at the time — across customer accounts. Reports on the number of affected users vary: some outlets cite approximately 249 recipients, others up to 695. Bithumb said it detected the error and froze trading and withdrawals for the affected accounts within roughly 20 to 35 minutes, and that the erroneous credits existed only on its internal ledger, with no actual on-chain bitcoin transfer taking place. Bithumb stated the incident was not linked to any external hacking or security breach. The exchange recovered approximately 99.7% of the mis-credited BTC (reported as 618,214 BTC recovered against a total of roughly 620,000 BTC credited), leaving a shortfall of about 1,786–1,788 BTC that had already been sold by recipients before accounts were frozen. Bithumb covered this shortfall using company reserves and stated no customer assets were lost. The exchange offered affected users compensation, including a flat payment to connected accounts, full reimbursement plus a 10% bonus to traders who sold at unfavorable prices during the incident, and a week of waived trading fees across all markets. South Korea's Financial Supervisory Service (FSS) opened a full-scale investigation into the incident.","heading":"February 2026 Mistaken 620,000 BTC Credit","severity":"critical","sources":[{"credibility":2,"name":"South Korean crypto firm mistakenly transfers US$40bil in bitcoin to users - New Straits Times","type":"news_article","url":"https://www.nst.com.my/amp/business/corporate/2026/02/1373429/south-korean-crypto-firm-mistakenly-transfers-us40bil-bitcoin"},{"credibility":2,"name":"Bithumb claws back 99.7% of overpaid Bitcoin, covers remaining shortfall - Cointelegraph","type":"news_article","url":"https://cointelegraph.com/news/bithumb-claws-back-99-7-of-overpaid-bitcoin-covers-remaining-shortfall"},{"credibility":2,"name":"Korean crypto firm accidentally sends $44 billion in bitcoin to users - WAM","type":"news_article","url":"https://www.wam.ae/en/article/bymd62c-south-korean-crypto-firm-accidentally-sends-44"}]},{"content":"Following the February 2026 payout error, Bithumb filed lawsuits in March 2026 against users who sold the mistakenly credited BTC and refused to return the proceeds, seeking repayment under South Korea's legal doctrine of unjust enrichment. On August 26 and 27, 2026, the Seoul Central District Court ruled in Bithumb's favor in two of these cases, ordering defendants to repay amounts of approximately 5 million won (about $3,600) and 194 million won (about $140,000). Two further cases, involving claims of about 14.8 million won (about $10,700) and 500 million won (about $362,000), remained undecided as of the August 2026 reporting.","heading":"Litigation Against Users Who Sold Mistakenly Credited Bitcoin","severity":"medium","sources":[{"credibility":2,"name":"Bithumb wins two lawsuits over erroneous distribution of 620,000 BTC - Forklog","type":"court_filing","url":"https://forklog.com/en/news/bithumb-wins-two-lawsuits-over-erroneous-distribution-of-620000-btc"}]},{"content":"On March 16, 2026, South Korea's Financial Intelligence Unit (FIU), under the Financial Services Commission, announced it had fined Bithumb 36.8 billion won (approximately $24.5 million) and ordered a six-month partial business suspension following a sanctions deliberation committee review. Regulators cited roughly 6.65 million violations of South Korea's Act on Reporting and Use of Specific Financial Transaction Information, including about 3.55 million failures to verify customer identities and about 3.04 million instances where transactions that should have been blocked were allowed to proceed. The FIU also found that Bithumb facilitated 45,772 crypto transfers involving 18 unregistered overseas virtual asset service providers (VASPs), despite the regulator having repeatedly warned the exchange to halt such transactions. The fine was described by multiple outlets as the largest AML penalty ever imposed on a South Korean virtual asset exchange, surpassing the 35.2 billion won fine issued to rival exchange Upbit in 2025. The partial suspension bars Bithumb from processing external crypto transfers for new customers from March 27 to September 26, 2026; existing users faced no trading restrictions, and new customers could still trade and deposit or withdraw Korean won during the suspension. Bithumb's CEO received a reprimand warning, and the exchange's compliance reporting officer was suspended for six months. The FIU had issued a preliminary notice of the suspension on March 9, 2026.","heading":"Record AML Fine and Partial Business Suspension (March 2026)","severity":"high","sources":[{"credibility":1,"name":"South Korea fines Bithumb $24.5M, orders six-month partial suspension over AML - Cointelegraph","type":"regulatory","url":"https://cointelegraph.com/news/south-korea-fines-bithumb-24-5m-six-month-partial-suspension-aml"},{"credibility":2,"name":"South Korea fines Bithumb $24M, orders 6-month partial business suspension - FXStreet","type":"news_article","url":"https://www.fxstreet.com/cryptocurrencies/news/south-korea-fines-bithumb-24m-orders-6-month-partial-business-suspension-202603170559"},{"credibility":2,"name":"South Korea fines Bithumb over AML - Bitcoin Magazine","type":"news_article","url":"https://bitcoinmagazine.com/news/south-korea-fines-bithumb-over-aml"}]},{"content":"South Korea's Personal Information Protection Commission (PIPC) fined Bithumb 210 million won (about $136,000) in a plenary decision made June 24, 2026 and announced June 25, 2026, for transferring users' personal data overseas without proper consent, and ordered corrective measures. The regulator found that between September and November 2025, Bithumb shared order-book data paired with USDT with a foreign exchange; although Bithumb had obtained user consent to share data with a platform called Stellar, it instead sent the data to a platform operated by BingX. A separate violation involved Bithumb sharing users' names, wallet addresses, and dates of birth with 13 other overseas exchanges to facilitate transfers without obtaining full user consent. The PIPC also issued broader guidance recommending that blockchain firms avoid recording personally identifying information on-chain.","heading":"Privacy Regulator Fine for Unauthorized Overseas Data Transfers","severity":"medium","sources":[{"credibility":1,"name":"Privacy watchdog fines Bithumb $135,700 for violating overseas data transfer rules - The Korea Times","type":"regulatory","url":"https://www.koreatimes.co.kr/economy/cryptocurrency/20260625/privacy-watchdog-fines-bithumb-135700-for-violating-overseas-data-transfer-rules"},{"credibility":2,"name":"South Korea fines Bithumb for sharing user data overseas without consent - The Block","type":"news_article","url":"https://www.theblock.co/post/406082/south-korea-bithumb-information-penalty"}]},{"content":"Bithumb had previously targeted a public listing as early as the second half of 2025, with a subsequent plan for a Nasdaq listing in the first half of 2026. In reporting published around April 1–2, 2026, Bithumb's CFO and a company spokesperson said the IPO timeline had been pushed back, with listing now expected in 2028 or later ('highly likely' after the start of 2028, per one report). The company cited ongoing work on accounting policies, internal controls, and internal verification. Multiple outlets linked the delay in part to the regulatory fallout from the February 2026 BTC payout error and the March 2026 AML fine and suspension, which outlets reported were under scrutiny as the company revised its listing plans.","heading":"Delayed IPO","severity":"low","sources":[{"credibility":2,"name":"Bithumb crypto exchange stretches IPO timeline to 2028 - The Block","type":"news_article","url":"https://www.theblock.co/post/396088/bithumb-crypto-exchange-stretches-ipo-timeline-2028"},{"credibility":2,"name":"Crypto exchange Bithumb postpones IPO bid amid economic uncertainty - DL News","type":"news_article","url":"https://www.dlnews.com/articles/markets/crypto-exchange-bithumb-postpones-ipo-bid-economic-uncertainty/"}]},{"content":"Bithumb has a history of security breaches predating the 2026 incidents. In July 2017, the exchange reported a breach, variously described as compromising an employee's personal computer and exposing personal data of over 30,000 users; estimates of financial losses from this incident vary widely across sources and could not be independently reconciled. In June 2018, hackers stole cryptocurrency reported at approximately 35 billion won (about $31.6 million); Bithumb moved remaining funds to cold storage and temporarily suspended deposits and withdrawals in response. In March 2019, Bithumb disclosed a theft of EOS and Ripple (XRP) tokens initially valued near $20 million (later reports cited roughly $17 million), which the company attributed to an insider rather than an external intrusion. These incidents are documented primarily by cybersecurity and crypto news outlets and Wikipedia; this section is included for historical context on the exchange's security track record and is lower-confidence than the 2026 events due to inconsistent figures across sources.","heading":"Prior Security Incidents (2017–2019)","severity":"medium","sources":[{"credibility":2,"name":"Bithumb cryptocurrency exchange hacked - The Hacker News","type":"news_article","url":"https://thehackernews.com/2019/03/bithumb-cryptocurrency-hacked.html?m=0"},{"credibility":2,"name":"Bithumb - Wikipedia","type":"other","url":"https://en.wikipedia.org/wiki/Bithumb"}]}],"sources_used":[{"credibility":2,"name":"South Korean crypto firm mistakenly transfers US$40bil in bitcoin to users - New Straits Times","type":"news_article","url":"https://www.nst.com.my/amp/business/corporate/2026/02/1373429/south-korean-crypto-firm-mistakenly-transfers-us40bil-bitcoin"},{"credibility":2,"name":"Bithumb claws back 99.7% of overpaid Bitcoin, covers remaining shortfall - Cointelegraph","type":"news_article","url":"https://cointelegraph.com/news/bithumb-claws-back-99-7-of-overpaid-bitcoin-covers-remaining-shortfall"},{"credibility":2,"name":"Korean crypto firm accidentally sends $44 billion in bitcoin to users - WAM","type":"news_article","url":"https://www.wam.ae/en/article/bymd62c-south-korean-crypto-firm-accidentally-sends-44"},{"credibility":2,"name":"Bithumb wins two lawsuits over erroneous distribution of 620,000 BTC - Forklog","type":"court_filing","url":"https://forklog.com/en/news/bithumb-wins-two-lawsuits-over-erroneous-distribution-of-620000-btc"},{"credibility":1,"name":"South Korea fines Bithumb $24.5M, orders six-month partial suspension over AML - Cointelegraph","type":"regulatory","url":"https://cointelegraph.com/news/south-korea-fines-bithumb-24-5m-six-month-partial-suspension-aml"},{"credibility":2,"name":"South Korea fines Bithumb $24M, orders 6-month partial business suspension - FXStreet","type":"news_article","url":"https://www.fxstreet.com/cryptocurrencies/news/south-korea-fines-bithumb-24m-orders-6-month-partial-business-suspension-202603170559"},{"credibility":2,"name":"South Korea fines Bithumb over AML - Bitcoin Magazine","type":"news_article","url":"https://bitcoinmagazine.com/news/south-korea-fines-bithumb-over-aml"},{"credibility":1,"name":"Privacy watchdog fines Bithumb $135,700 for violating overseas data transfer rules - The Korea Times","type":"regulatory","url":"https://www.koreatimes.co.kr/economy/cryptocurrency/20260625/privacy-watchdog-fines-bithumb-135700-for-violating-overseas-data-transfer-rules"},{"credibility":2,"name":"South Korea fines Bithumb for sharing user data overseas without consent - The Block","type":"news_article","url":"https://www.theblock.co/post/406082/south-korea-bithumb-information-penalty"},{"credibility":2,"name":"Bithumb crypto exchange stretches IPO timeline to 2028 - The Block","type":"news_article","url":"https://www.theblock.co/post/396088/bithumb-crypto-exchange-stretches-ipo-timeline-2028"},{"credibility":2,"name":"Crypto exchange Bithumb postpones IPO bid amid economic uncertainty - DL News","type":"news_article","url":"https://www.dlnews.com/articles/markets/crypto-exchange-bithumb-postpones-ipo-bid-economic-uncertainty/"},{"credibility":2,"name":"Bithumb cryptocurrency exchange hacked - The Hacker News","type":"news_article","url":"https://thehackernews.com/2019/03/bithumb-cryptocurrency-hacked.html?m=0"},{"credibility":2,"name":"Bithumb - Wikipedia","type":"other","url":"https://en.wikipedia.org/wiki/Bithumb"}],"summary":"Bithumb is one of South Korea's largest centralized cryptocurrency exchanges. In 2026 it suffered a major operational failure — a promotional payout error that briefly credited roughly 620,000 BTC (over $40 billion in book value) to customer accounts — and was separately hit with South Korea's largest-ever anti-money-laundering fine against a virtual asset exchange, plus a smaller privacy-related penalty. The exchange has also pushed its long-planned IPO back to 2028 or later. Bithumb says it fully covered the shortfall from the payout error and is pursuing litigation against users who will not return mistakenly obtained funds.","timeline":[{"date":"2017-07","event":"Bithumb discloses a security breach, with reports describing compromise of an employee's personal computer and exposure of personal data; loss estimates vary widely across sources.","source":"The Hacker News / Wikipedia","source_url":"https://en.wikipedia.org/wiki/Bithumb"},{"date":"2018-06","event":"Hackers steal approximately 35 billion won (about $31.6 million) in cryptocurrency from Bithumb; exchange moves funds to cold storage and suspends deposits/withdrawals.","source":"The Hacker News","source_url":"https://thehackernews.com/2019/03/bithumb-cryptocurrency-hacked.html?m=0"},{"date":"2019-03","date_evidence":"On March 29, Bithumb said it had been hacked, blaming insiders, with nearly $20 million in EOS and Ripple tokens stolen.","date_original":"2019-03-29","event":"Bithumb discloses theft of EOS and XRP tokens worth nearly $20 million (later reduced to roughly $17 million), attributed to an insider.","source":"The Hacker News","source_url":"https://thehackernews.com/2019/03/bithumb-cryptocurrency-hacked.html?m=0"},{"date":"2026-02","event":"A Bithumb employee mistakenly enters a promotional payout in BTC instead of KRW, crediting roughly 620,000 BTC (over $40 billion in book value) to customer accounts; trading and withdrawals are frozen within about 20–35 minutes.","source":"New Straits Times / Cointelegraph","source_url":"https://www.nst.com.my/amp/business/corporate/2026/02/1373429/south-korean-crypto-firm-mistakenly-transfers-us40bil-bitcoin"},{"date":"2026-03","event":"Bithumb files lawsuits against users who sold the mistakenly credited BTC and refused to return the proceeds.","source":"Forklog","source_url":"https://forklog.com/en/news/bithumb-wins-two-lawsuits-over-erroneous-distribution-of-620000-btc"},{"date":"2026-03","date_evidence":"The FIU had issued a preliminary notice of the partial suspension on March 9.","date_original":"2026-03-09","event":"South Korea's FIU issues preliminary notice of a partial business suspension against Bithumb.","source":"Cointelegraph","source_url":"https://cointelegraph.com/news/south-korea-fines-bithumb-24-5m-six-month-partial-suspension-aml"},{"date":"2026-03-16","date_evidence":"The reports date the decision to March 16, 2026.","event":"South Korea's FIU fines Bithumb 36.8 billion won (about $24.5 million) and orders a six-month partial business suspension over roughly 6.65 million AML violations — the largest such fine ever imposed on a Korean virtual asset exchange.","source":"Cointelegraph / FXStreet / Bitcoin Magazine","source_url":"https://cointelegraph.com/news/south-korea-fines-bithumb-24-5m-six-month-partial-suspension-aml"},{"date":"2026-03","date_original":"2026-03-27","event":"Bithumb's six-month partial business suspension (barring external crypto transfers for new customers) begins, running through September 26, 2026.","source":"Cointelegraph","source_url":"https://cointelegraph.com/news/south-korea-fines-bithumb-24-5m-six-month-partial-suspension-aml"},{"date":"2026-04","event":"Bithumb discloses its IPO timeline has slipped to 2028 or later, citing internal controls work and regulatory fallout.","source":"The Block / DL News","source_url":"https://www.theblock.co/post/396088/bithumb-crypto-exchange-stretches-ipo-timeline-2028"},{"date":"2026-06-24","date_evidence":"The plenary decision was made on June 24, 2026, and announced the next day.","event":"South Korea's Personal Information Protection Commission fines Bithumb 210 million won for unauthorized overseas transfer of user data.","source":"The Korea Times","source_url":"https://www.koreatimes.co.kr/economy/cryptocurrency/20260625/privacy-watchdog-fines-bithumb-135700-for-violating-overseas-data-transfer-rules"},{"date":"2026-08-26","date_evidence":"The court ruled in Bithumb's favor on August 26 and 27, 2026, in two lawsuits.","event":"Seoul Central District Court rules in Bithumb's favor in the first of two lawsuits against users who sold mistakenly credited BTC.","source":"Forklog","source_url":"https://forklog.com/en/news/bithumb-wins-two-lawsuits-over-erroneous-distribution-of-620000-btc"},{"date":"2026-08-27","date_evidence":"The court ruled in Bithumb's favor on August 26 and 27, 2026, in two lawsuits.","event":"Seoul Central District Court rules in Bithumb's favor in the second lawsuit; two further cases remain pending.","source":"Forklog","source_url":"https://forklog.com/en/news/bithumb-wins-two-lawsuits-over-erroneous-distribution-of-620000-btc"}]},"v":1}