When People Lost Their Bitcoin

The world’s dominant early Bitcoin exchange collapsed in February 2014 after years of theft, weak controls and mismanagement. Roughly 650,000 BTC remained unaccounted for after the later discovery. Court-supervised partial repayments in Bitcoin and Bitcoin Cash began in July 2024—more than ten years after the collapse.

Bitcoinica suffered multiple compromises in only a few months. Confused records, creditor disputes and liquidation made the final customer loss difficult to calculate—a warning that poor accounting can compound a security failure.

Trendon Shavers promised returns as high as 7% per week. The SEC described it as a Bitcoin-denominated Ponzi scheme. The large BTC figure measures deposits and flows through the operation, not a one-time wallet theft or a precise final net loss.

A hard drive believed to contain the wallet’s private key was accidentally discarded. No thief took the coins; the Bitcoin remains on the ledger but cannot be spent without the key. A court rejected his effort to force access to the landfill.

The online-wallet service was hacked and did not have enough reserves to make every user whole. The operator offered partial repayment, illustrating the risk of trusting a hosted wallet with the only spendable keys.

A phishing and social-engineering campaign compromised the exchange’s operational wallet. Bitstamp shut down temporarily, rebuilt its systems and covered the loss. It is included as a near-miss for customers, not a permanent customer loss.

Bitfinex initially spread the loss across customer accounts and issued compensation tokens, which it later redeemed. U.S. authorities subsequently seized most of the stolen Bitcoin. The case shows that recovery can happen, but may take years.

Victims transferred Bitcoin into an alleged high-yield lending program. Because the operation revolved around a separate token, this page does not count its headline dollar figure as a Bitcoin-only loss; it is included because Bitcoin was the entry asset many victims surrendered.

Founder Gerald Cotten controlled the platform and used customer assets to cover trading losses and personal spending. The OSC concluded the collapse resulted from fraud—not simply from Cotten dying with the only passwords, as early reports suggested. A BTC-only final loss is not available.

Attackers used phishing, malware and stolen account credentials. Customers did not ultimately bear the theft, so this is another example of a custodian surviving a large breach rather than a permanent client loss.

The scheme promised high returns and stopped withdrawals in 2019. It collected multiple asset types, so the traced BTC total is not the same as a final net Bitcoin loss; recovered, transferred and laundered funds complicate the calculation.

Promoters sold supposed shares in Bitcoin mining pools and displayed false mining returns. BitClub was not an exchange hack: it was a fraudulent investment and recruitment scheme that accepted victims’ Bitcoin.

Arkham Intelligence reported that an attacker apparently derived LuBian’s weak keys and moved the funds in December 2020. LuBian never publicly confirmed the event, so this remains an on-chain analytical conclusion rather than a fully documented company disclosure.

Customers had transferred ownership and control of their BTC and other assets to earn yield. Founder Alex Mashinsky later pleaded guilty and received a 12-year prison sentence. Bankruptcy distributions recovered part of creditor claims, but the headline figure is not BTC-only.

Both lenders failed during the 2022 credit crisis. BlockFi later announced recovery of the allowed dollar value of eligible customer claims. A dollar-based repayment after Bitcoin’s price changes is not necessarily equivalent to returning the original BTC.

FTX secretly transferred customer deposits to Alameda Research, where they were spent and lost. Bankman-Fried was convicted and sentenced to 25 years. Bankruptcy creditors began receiving dollar-based distributions, but customers who deposited BTC did not necessarily receive the same amount of BTC back.

Authorities attributed the theft to North Korean-linked actors. They compromised an employee at a wallet-software provider, stole session information and manipulated a legitimate DMM transaction request.