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Part of the CustodyStress archive of observed Bitcoin custody incidents
Undocumented Recovery ProcedureExchange custody

Undocumented Recovery Procedure — Exchange custody

Cases where no documentation existed for how to access an exchange account. Exchange account recovery typically requires specific identity documents, email access, and procedural knowledge that heirs frequently lack.

32% of all Exchange custody cases in the archive involve this structural dependency. The blocked rate among them is 74% — 5 points above the archive-wide blocked rate of 69%. The most common recovery path is exchange support.

Archive analysis — 85 cases
Outcomes
74% of determinate cases resulted in blocked access — 5 percentage points above the archive-wide average of 69%.
Documentation coverage
54% of cases have indeterminate outcomes — higher than the archive average of 43%.
Primary stress condition
47% of cases involve vendor lockout. Passphrase unavailable accounts for a further 25%.
Recovery path
Exchange Support is the most documented recovery path (20 cases, 24% of subset). Of those with a determinate outcome, 86% resulted in recovered or constrained access.
Documentation
81% of cases had partial documentation — insufficient to complete recovery without the holder's direct involvement.
Time distribution
Cases span 2013–2025. Only 9% occurred in 2022 or later — concentrated in earlier periods.
29
Blocked
6
Constrained
4
Survived
46
Indeterminate

90% of determinate cases resulted in blocked or constrained access.

85 observed cases
Blocked
29 (34%)
Constrained
6 (7%)
Survived
4 (5%)
Indeterminate
46 (54%)
2 BTC Vanished from Blockchain.com Wallet: Legacy Address Migration Gone Wrong
Exchange custody
Indeterminate 2025
In February 2025, a BitcoinTalk user reported that 2 BTC deposited to a Blockchain.com wallet from a mining computer in 2016 had become inaccessible. The wallet
Blockchain.com Imported Address Recovery: Funds Visible but Inaccessible
Exchange custody
Indeterminate 2024
Cryptflower created a Bitcoin wallet on Blockchain.com in 2014 and retained a 12-word BIP39 seed phrase saved in 2018. By January 2024, the user confirmed the o
BRD Wallet Access Loss: Incomplete Backup, Missing Seed Phrase
Exchange custody
Blocked 2024
MLNiemczyk2411 created a BRD wallet several years before November 2024 but neglected to properly document the recovery materials. During wallet initialization,
Blockchain.com Account Access Failure: 2014 Wallet, Dormant 10 Years, Support Unresponsive
Exchange custody
Indeterminate 2024
Between 2014 and early 2024, at least three users encountered custody access failures on Blockchain.com (formerly Blockchain.info). Osiris100 created a wallet o
Blockchain.com Account Frozen for Inactivity – User Unable to Recover Forgotten Wallet
Exchange custody
Indeterminate 2023
In February 2023, a user reported being contacted by an entity claiming to represent Blockchain.com. The message stated that the user had created a Bitcoin wall
Incomplete Seed Phrase and Lost Email Access Lock Blockchain.info Wallet
Exchange custody
Indeterminate 2023
In September 2023, a forum user posted on behalf of an elderly relative seeking recovery assistance for a Bitcoin wallet created on Blockchain.info in 2015 or 2
Legacy Blockchain.com Wallet Inaccessible: Private Keys Don't Match Funded Address
Exchange custody
Blocked 2022
In November 2022, a user (Gemwolf) discovered an old hard drive containing a wallet.dat file and notes from his 2012 Bitcoin experimentation period. Mining acti
Blockchain.com and Exchange Account Loss: Two Cases of Forgotten Credentials and Theft
Exchange custody
Blocked 2022
Two separate custody failures surfaced on BitcoinTalk in January 2022, both rooted in lost access to hosted wallet platforms. Kortez011 reported losing access t
Valid Seed Phrase, Inaccessible Address: Coinbase Derivation Path Incompatibility
Exchange custody
Indeterminate 2021
In January 2021, forum user Folio sought help accessing Bitcoin held in a friend's Coinbase wallet. The friend had provided the seed phrase, but Folio could not
Blockchain.info Legacy Wallet Access Loss: Password Forgotten, Recovery Phrase Format Incompatible
Exchange custody
Indeterminate 2021
In April 2021, a Bitcoin holder discovered they could no longer access a Blockchain.info wallet opened in 2014 after forgetting the account password. The platfo
Blocktrail Wallet Recovery: Lost Password, Multiple Backup Seeds, Platform Tool Failure
Exchange custody
Constrained 2021
LSU777, a BitcoinTalk forum user, attempted recovery of a Blocktrail-hosted wallet created in the pre-fork era (circa 2016) after losing the primary password. T
Ninki Wallet Recovery Failure: Seed Phrase Insufficient Without Derivation Path Documentation
Exchange custody
Indeterminate 2021
Ninki was an online wallet service that ceased operation, trapping user funds behind a discontinued platform. The user Sycorax21 held the theoretically complete
Coinbase Wallet Lockout with Corrupted Google Drive Backup
Exchange custody
Blocked 2021
In June 2021, a Coinbase Wallet user reported being locked out of their account but believed recovery was possible because they had exported a backup file to Go
Five Old Blockchain.info Wallets Inaccessible: Non-Standard Recovery Phrases Beyond Recovery Tools
Exchange custody
Indeterminate 2020
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
Indeterminate 2020
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
Blockchain.info Wallet Access Lost: Destroyed Phone Note, Discarded Seed Paper, Partial Password
Exchange custody
Indeterminate 2020
In April 2020, a forum user described a friend's custody access failure involving a Blockchain.info hosted wallet (the platform later rebranded to Blockchain.co
Blockchain.com Dormant Accounts: Lost Passwords and Missing Backup Files
Exchange custody
Blocked 2019
Between approximately 2013 and 2019, multiple users of Blockchain.com (formerly Blockchain.info) experienced permanent loss of Bitcoin held in dormant accounts.
Pre-2014 Blockchain.info Wallet: Non-Standard Mnemonic Format Blocks Recovery
Exchange custody
Indeterminate 2019
In May 2019, a Bitcoin holder identified as pizzdaniel posted to BitcoinTalk describing a multi-year custody failure involving wallets created on blockchain.inf
Blockchain.com Web Wallet Access Failures: Lost Passwords and Inaccessible Email Recovery
Exchange custody
Blocked 2019
Between 2013 and 2019, several users created Bitcoin wallets on blockchain.com (formerly blockchain.info), a web-based custodial platform popular during early B
Passphrase unavailable — exchange custody, unknown (2019)
Exchange custody
Blocked 2019
A 2019 BitcoinTalk thread documented a recurring custody failure pattern affecting blockchain.com (formerly blockchain.info) users from the 2011–2014 era. The o
QuadrigaCX Exchange Collapse: CEO Death Blocks Access to $190M in Customer Cryptocurrency
Exchange custody
Blocked 2019
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
Block.io Dashboard Access Failure: User Unable to Move BTC Despite Holding Private Keys
Exchange custody
Indeterminate 2019
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
Blockchain.info Wallet Access Lost After Signup—Recovery Phrase Known
Exchange custody
Indeterminate 2018
On March 16, 2018, a user with the handle ilovegambling created a new Blockchain.info wallet to receive Bitcoin from an online betting platform. The user record
QuadrigaCX Gerald Cotten Death: C$190M in Cold Storage Permanently Inaccessible
Exchange custody
Blocked 2018
Gerald Cotten, 30, founded and operated QuadrigaCX as Canada's largest cryptocurrency exchange. He managed the platform's operations, customer support, and crit
Mt. Gox Account Access Permanently Blocked Following Owner Death and Credential Reset
Exchange custody
Blocked 2018
Mt. Gox ceased operations in February 2014 following the loss of approximately 850,000 Bitcoin. Users with dormant accounts on the platform faced an immediate c
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Related pages
Terms guide
Survived
Access remained possible under the reported conditions.
Constrained
Access remained possible, but only with delay, dependence, or significant difficulty.
Blocked
Access was not possible under the reported conditions.
Indeterminate
There was not enough information to determine the outcome.
Survivability
The degree to which a custody system maintains the possibility of authorized recovery under stress.
Archive inclusion criteria

This archive documents cases where a legitimate owner, heir, or authorized party encountered barriers accessing or recovering Bitcoin due to a failure in the custody arrangement. The central question for inclusion is: did the custody structure fail a legitimate access or recovery attempt?

A case must satisfy all three of the following to be included:

  1. Legitimate access attempt. The person attempting to access or recover the Bitcoin was the owner, a designated heir, an executor, a legal authority, or another party with a legitimate claim — not a thief, attacker, or unauthorized third party.
  2. Custody structure failure. The failure was caused by a property of the custody arrangement — missing credentials, structural dependencies, documentation gaps, knowledge concentration, legal barriers, or institutional constraints — not market conditions, individual-level fraud or theft, or protocol-level issues. Platform-level failures that block legitimate user access are in scope regardless of their cause.
  3. Documentable outcome or access constraint. The case must have a stated or inferable outcome: access blocked, access constrained, access delayed, or access eventually achieved through a recovery path. Cases with entirely unknown outcomes are included only where the structural failure is documented and the constraint is unambiguous.
  • Owner death or incapacity — Bitcoin held in self-custody that becomes inaccessible to heirs or designated parties because credentials, documentation, or operational knowledge were not transferred
  • Passphrase loss — BIP39 passphrase forgotten or unavailable, blocking access to a funded wallet even where the seed phrase is present
  • Seed phrase or wallet backup unavailable — no independent recovery path existed or the backup was destroyed, lost, or never created
  • Device loss without independent backup — hardware wallet, phone, or computer lost or destroyed with no recovery path outside the device
  • Documentation absent or ambiguous — heirs or executors cannot determine that Bitcoin exists, which wallet holds it, or how to access it
  • Knowledge concentration — only one person knew the procedure, passphrase, or access method; that person is dead, incapacitated, or unreachable
  • Multisig quorum failure — a threshold signature arrangement cannot be completed because signers are unavailable, uncooperative, incapacitated, or have lost their keys
  • Legal authority / access mismatch — a court order, probate ruling, or power of attorney establishes legal entitlement but provides no technical path to access
  • Institutional custody barrier — exchange or platform hacks, insolvency, regulatory seizure, or operational failure that caused a access constraint or failure for legitimate users, whether temporary, prolonged, or permanent. The failure of the custodian to remain available or solvent is itself the in-scope event.
  • Forced relocation or geographic constraint — physical access to a device or location required for recovery is blocked by displacement, border restrictions, or political circumstances
  • Coercion — the holder was compelled under threat to transfer Bitcoin or disclose credentials during an access event
  • Hidden asset discovery — heirs or executors locate a wallet or account but cannot access it due to missing credentials or operational knowledge
  • Market losses, investment losses, yield scheme losses, or Ponzi scheme losses
  • Hacks or theft targeting an individual's personal security (phishing, SIM swap, social engineering, malware) where the custody architecture itself did not fail
  • Unauthorized transfers where the holder's custody system was not the cause of the failure
  • Ordinary transaction mistakes — wrong-address sends, fee errors, mistaken amounts
  • Protocol-level failures — cryptographic vulnerabilities, consensus bugs, firmware integrity failures
  • Deliberate burns or tribute burns
  • Cases where the stated loss is unverifiable and no structural custody failure is described

Cases are drawn from public sources including forum posts, news reporting, court documents, academic research, and direct submissions. Each case is reviewed against the inclusion criteria above before publication. Source material is retained and available on request for documented cases.

The archive is observational and descriptive. It does not attempt to document all Bitcoin custody failures — only those meeting the criteria above with sufficient documentation to describe the structural failure and its outcome.