Part of the CustodyStress archive of observed Bitcoin custody incidents
Halving Cycle 3 (2017–2020) — Vendor lockout
Exchange failures from Halving Cycle 3 (2017–2020). The post-2017 bull cycle produced a surge of new exchange users, followed by a wave of closures in the 2018–2019 bear market. QuadrigaCX — where the founder died holding sole custody — is the defining institutional failure of this cycle.
54 cases in this intersection. 59% of determinate cases resulted in a blocked outcome and 3% in access survived. The most common recovery path is exchange support.
Archive analysis — 54 cases
Outcomes
59% of determinate cases resulted in blocked access — 10 percentage points below the archive-wide average of 69%. Only 3% resulted in recovered access — one of the lower survival rates in the archive. 38% resulted in constrained recovery.
Documentation coverage
31% of cases have indeterminate outcomes — higher than the archive average of 43%.
Custody type
96% of cases involved exchange custody, followed by software wallet at 4%.
Recovery path
Exchange Support is the most documented recovery path (19 cases, 35% of subset). Of those with a determinate outcome, 92% resulted in recovered or constrained access.
Documentation
59% of cases had present and interpretable documentation — yet still produced a blocked or constrained outcome.
Scale
30% of cases involved large or very large holdings (10+ BTC).
22
Blocked
14
Constrained
1
Survived
17
Indeterminate
97% of determinate cases resulted in blocked or constrained access.
54 observed cases
Blocked
22 (41%)
Constrained
14 (26%)
Survived
1 (2%)
Indeterminate
17 (31%)
Altsbit Exchange Hack (February 2020): Institutional Failure, Partial Recovery
Exchange custody
Altsbit, an Italian cryptocurrency exchange that had been operational for only a few months, suffered a catastrophic security breach in February 2020. Attackers
Coinbase Account Lockout: Multiple Users Denied Access Despite Identity Verification (2016–2020)
Exchange custody
Between December 2020 and the time of posting, multiple Coinbase users reported extended account lockouts that prevented trading, withdrawals, and even portfoli
Six Bitcoin Custody Failures: Exchange Collapse, Laptop Theft, and Deleted Wallets (2020)
Exchange custody
In March 2020, a BitcoinTalk forum thread aggregated six real-world Bitcoin access failures from individual users. User garyrowe reported losing keys to a non-B
Five Old Blockchain.info Wallets Inaccessible: Non-Standard Recovery Phrases Beyond Recovery Tools
Exchange custody
In July 2020, forum user gbola reported discovering five old Blockchain.info recovery phrases originating from approximately 2014, when the user's family were e
Blockchain.com Account Inaccessible: Forgotten Email Address and Missing Recovery Words
Exchange custody
In approximately 2016, the user angly11 created a Blockchain.com hosted wallet account but committed a critical documentation failure: they did not record the e
2.9 BTC in Unidentified Web Wallet from 2012–2013: Provider Unknown, Access Impossible
Exchange custody
In May 2020, a BitcoinTalk user reporting under the handle cyptomania rediscovered Bitcoin documentation while conducting routine record cleanup. The user had s
Livecoin Exchange Compromised by Server Attack — Price Manipulation, Permanent Shutdown
Exchange custody
Livecoin, a Russian cryptocurrency exchange, suffered a critical infrastructure compromise on 23 December 2020 when attackers gained control of the exchange's s
KuCoin Exchange Breach September 2020: $280M Stolen, $204M Recovered
Exchange custody
On September 26, 2020, KuCoin announced a security breach affecting its hot wallets. Attackers with access to private keys stole approximately $280 million in c
Eterbase Exchange Breach: $5.4M Stolen, Limited Recovery
Exchange custody
On September 8, 2020, Eterbase, a Slovakian cryptocurrency exchange, discovered unauthorised transfers totalling approximately $5.4 million from its hot wallets
Hidden wallet discovered — software wallet (2020)
Software wallet
In September 2020, a Bitcoin holder created a paper wallet using bitcoinpaperwallet.com, a website presenting itself as a legitimate tool for generating offline
Pre-2014 Blockchain.info Wallet: Non-Standard Mnemonic Format Blocks Recovery
Exchange custody
In May 2019, a Bitcoin holder identified as pizzdaniel posted to BitcoinTalk describing a multi-year custody failure involving wallets created on blockchain.inf
Einstein Exchange Vancouver: $16M CAD Claimed Liabilities, Insolvent Collapse 2019
Exchange custody
Einstein Exchange, a Vancouver-based cryptocurrency platform founded by Michael Ongun Gokturk, marketed itself as Canada's fastest-growing digital currency exch
Upbit Exchange Hot Wallet Breach — 342,000 ETH Stolen, November 2019
Exchange custody
On November 27, 2019, the South Korean exchange Upbit discovered that 342,000 ETH—valued at approximately $49 million USD at the time—had been transferred from
Bitrue Singapore Exchange Security Breach — $4.2M Theft, Full User Refund
Exchange custody
On June 27, 2019, Singapore-based exchange Bitrue discovered a $4.2 million security breach affecting 90 user accounts. An attacker had exploited a weakness in
CoinBene Exchange Hack — $100M+ Stolen, Maintenance Cover-Up, March 2019
Exchange custody
CoinBene, a cryptocurrency exchange, abruptly went offline in March 2019 citing scheduled maintenance. Within days, blockchain analysts at multiple firms detect
QuadrigaCX Exchange Collapse: $190M Bitcoin Lost After Owner's Death
Exchange custody
QuadrigaCX was a Canadian cryptocurrency exchange that collapsed in 2019 following the sudden death of its founder and sole operator. The exchange held approxim
QuadrigaCX Exchange Collapse (April 2019): Mass Custody Loss
Exchange custody
QuadrigaCX, founded in 2013 and one of Canada's largest cryptocurrency exchanges, ceased operations on April 15, 2019, with approximately 115,000 users unable t
Bithumb $13M EOS Insider Theft April 2019: Platform Lockout and Third Security Breach
Exchange custody
On April 1, 2019, South Korean exchange Bithumb detected abnormal withdrawal patterns in its internal monitoring systems and halted all deposit and withdrawal s
Blockchain.info Hosted Wallet: Valid Backup Defeated by Email Authentication Failure
Exchange custody
In September 2019, a BitcoinTalk user identified as patparry reported a custody access failure involving a Blockchain.info hosted wallet. The account had remain
QuadrigaCX Exchange Collapse: CEO Death Blocks Access to $190M in Customer Cryptocurrency
Exchange custody
QuadrigaCX, founded in 2013 and operating as one of Canada's largest cryptocurrency exchanges, ceased operations in January 2019 following the death of CEO and
Cryptopia Exchange Hack and Liquidation: 960,000 Frozen Accounts, $400M Distributed Over 5 Years
Exchange custody
Cryptopia, a Christchurch-based cryptocurrency exchange serving 1.4 million registered users across approximately 900 trading pairs, suffered a critical securit
DragonEx Singapore Exchange Compromised by Lazarus Group — User Funds Stolen March 2019
Exchange custody
DragonEx, a Singapore-based cryptocurrency exchange, suffered a critical security breach on March 24, 2019, when attackers gained access to internal systems and
BITPoint Exchange Hack — $23M Customer Cryptocurrency Stolen, July 2019
Exchange custody
On July 12, 2019, BITPoint, operated by Tokyo-listed Remixpoint Inc., discovered unauthorised outflows totalling approximately 3.5 billion yen ($32 million USD)
Block.io Dashboard Access Failure: User Unable to Move BTC Despite Holding Private Keys
Exchange custody
In September 2019, a Bitcoin user holding funds on Block.io encountered a critical access barrier. When attempting to log into the custodial wallet dashboard, t
MapleChange Exchange Collapse: $5M Missing, Hack Unverified, No Recovery
Exchange custody
MapleChange, a Canadian cryptocurrency exchange, announced on October 28, 2018, that it had suffered a security breach resulting in the loss of approximately $5
Browse by halving cycle and stress
Halving Cycle 4 (2021–2024) — Vendor lockout
Halving Cycle 4 (2021–2024) — Seed phrase unavailable
Halving Cycle 4 (2021–2024) — Passphrase unavailable
Halving Cycle 4 (2021–2024) — Device loss
Halving Cycle 4 (2021–2024) — Coercion
Halving Cycle 3 (2017–2020) — Passphrase unavailable
Halving Cycle 3 (2017–2020) — Seed phrase unavailable
Halving Cycle 3 (2017–2020) — Device loss
Halving Cycle 3 (2017–2020) — Coercion
Halving Cycle 2 (2013–2016) — Passphrase unavailable
Halving Cycle 2 (2013–2016) — Seed phrase unavailable
Halving Cycle 2 (2013–2016) — Vendor lockout
Halving Cycle 2 (2013–2016) — Device loss
Halving Cycle 1 (2009–2012) — Seed phrase unavailable
Halving Cycle 1 (2009–2012) — Passphrase unavailable
Halving Cycle 1 (2009–2012) — Vendor lockout
Halving Cycle 1 (2009–2012) — Device loss
All cases