CustodyStress
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Part of the CustodyStress archive of observed Bitcoin custody incidents
Single-Person KnowledgeExchange custody

Single-Person Knowledge — Exchange custody

Cases where only one person understood how to access an exchange account. When that person became unavailable — through death, incapacity, or absence — no one else could navigate the account recovery process.

38% of all Exchange custody cases in the archive involve this structural dependency. The blocked rate among them is 80% — 11 points above the archive-wide blocked rate of 69%. The most common recovery path is exchange support.

47
Blocked
6
Constrained
6
Survived
41
Indeterminate

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

100 observed cases
Blocked
47 (47%)
Constrained
6 (6%)
Survived
6 (6%)
Indeterminate
41 (41%)
Kevin Durant Locked Out of Coinbase Bitcoin Account for 9 Years After 2016 Purchase
Exchange custody
Constrained 2016
Kevin Durant purchased Bitcoin on Coinbase in September 2016 at approximately $650 per coin, following repeated conversations with Golden State Warriors teammat
Blockchain.info Wallet Password Loss: No Recovery Options — February 2016
Exchange custody
Indeterminate 2016
In February 2016, a BitcoinTalk user posted on behalf of a friend who had lost the password to a Blockchain.info hosted wallet. The friend retained only an iden
Blockchain.com Wallet (2016): Partial Password Recovery Attempt, Seed Phrase Absent
Exchange custody
Blocked 2016
The subject created a Blockchain.com account in 2016 and deposited approximately 0.03 BTC (valued at roughly $20 at 2016 exchange rates of $600/BTC). Immediatel
Online Wallet Password Lost Without Seed Phrase Backup
Exchange custody
Indeterminate 2016
In November 2017, a BitcoinTalk user (mattmaxx) discovered they had lost access to an online Bitcoin wallet created approximately one year earlier on a laptop t
Blockchain.info Wallet Access Lost After SD Card Automatic Format During Device Migration
Exchange custody
Indeterminate 2016
In June 2016, a Blockchain.info user with the handle 'Graver' lost access to their Bitcoin holdings following a device migration that exposed the fragility of s
KipCoin Exchange Linode Hosting Compromise: October 2014 Breach, February 2015 Disclosure
Exchange custody
Indeterminate 2015
KipCoin operated as a custodial Bitcoin exchange running infrastructure on Linode virtual private servers. In June 2014, Linode suffered a security breach that
Institutional lockout — exchange custody, Australia (2015)
Exchange custody
Constrained 2015
In August 2015, the Australian Bitcoin exchange igot ceased all operations and communications, leaving customers unable to access their holdings or funds. Reddi
Forgotten Blockchain.info Password: Client-Side Encryption Locks €100 Bitcoin Permanently
Exchange custody
Blocked 2015
On September 17, 2015, a Blockchain.info user with the forum username Seporstia posted requesting help recovering access to a hosted wallet after forgetting the
0.3 BTC Lost After Uninstalling Blockchain.info Desktop Wallet Without Backup
Exchange custody
Blocked 2015
In June 2015, a user identified as Williams2017 received approximately 0.3 BTC (then valued at roughly $70 USD) from an entity called 'www.instantgold.ng' to th
Recovery of Dormant Blockchain.info Wallet via Legacy 20-Word Mnemonic (2017)
Exchange custody
Survived 2014
Roland808, a BitcoinTalk user, discovered a text file on their computer in March 2017 dated from 2014 containing a label 'bitcoin nmemonic' followed by 20 rando
Password Safe Crash Leaves Blockchain.info Wallet Inaccessible
Exchange custody
Indeterminate 2014
In January 2014, a BitcoinTalk user identified as StinkyS4L discovered that their Password Safe application had crashed, rendering all stored passwords inaccess
Lost Access to 2014 blockchain.info Wallets: Non-Standard Recovery Mnemonics, No Support Response
Exchange custody
Indeterminate 2014
In July 2020, forum user gbola reported locating five recovery mnemonics created circa 2014 when blockchain.info was in its early operations. The user's entire
BitInstant Exchange Collapse: Charlie Shrem Arrest Freezes Customer Funds
Exchange custody
Blocked 2014
BitInstant operated as one of the earliest and most prominent custodial Bitcoin exchanges in the United States, co-founded by Charlie Shrem with backing from th
Mt. Gox Collapse Overshadows Father's Estate: Unrecover­able Bitcoin Loss
Exchange custody
Blocked 2014
Around 2012, a Reddit user posted in a Mt. Gox horror story thread describing a custody failure layered with family loss. His father had died approximately one
Forgotten Password on Blockchain.info Web Wallet: 0.22 BTC Inaccessible
Exchange custody
Indeterminate 2014
In October 2014, a Bitcoin Forum user (findftp) sought technical assistance for a friend who had lost access to a Blockchain.info wallet containing 0.22 BTC (ap
Blockchain.com 2014 Hosted Wallet: Password and Seed Phrase Loss
Exchange custody
Indeterminate 2014
A Blockchain.com customer acquired approximately 0.5 BTC in 2014 using the platform's hosted wallet service. Over the years, the original password and recovery
0.5 BTC Lost in Blockchain.info Encrypted Wallet (2014)
Exchange custody
Indeterminate 2014
In January 2014, an early Bitcoin adopter purchased BTC on LocalBitcoins and transferred 0.5 BTC to a public address in August of that year. The user recorded o
Forgotten Password on Blockchain.info: 0.22 BTC Access Lost, Brute-Force Recovery Attempted
Exchange custody
Indeterminate 2014
In October 2014, a BitcoinTalk forum user reported that their friend had become locked out of a blockchain.info wallet containing 0.22 BTC after forgetting the
Matthew Moody: Early Bitcoin Miner Dies in Plane Crash, Estate Inaccessible
Exchange custody
Blocked 2013
Matthew Philip Moody, 26, of San Ramon, California, was an early Bitcoin miner who accumulated coins during the network's early years using his home computer. O
2013 Blockchain.info AES-Encrypted Wallet: Password Lost, Recovery Tooling Exhausted
Exchange custody
Indeterminate 2013
In March 2013, during a two-month personal mining experiment, a user registered a wallet on blockchain.info and received an AES-encrypted backup file via email
Blockchain.info Web Wallet (2013): Silent Login Failure, Unresolved After 3 Months
Exchange custody
Blocked 2013
In late 2013, a user created a Bitcoin wallet on blockchain.info, then one of the most popular web-based custodial platforms. The wallet remained accessible dur
Blockchain.info Web Wallet: Imported Private Key Vanished After Sync Popup
Exchange custody
Blocked 2013
In February 2013, a BitcoinTalk user (BurtW) generated a vanity address using vanitygen and imported the private key into his Blockchain.info web wallet account
Blockchain.info Hosted Wallet Recovery: Password Reset via Seed Phrase (2013)
Exchange custody
Survived 2013
PandaNL opened a Blockchain.info hosted wallet in 2013 and over several years forgot the account password. The user retained three critical pieces of recovery i
Blockchain.info 2013–2014 Wallet Access Failure: Encrypted Files, Lost Password, Functional Recovery Phrase
Exchange custody
Indeterminate 2013
User 'marvin42' created Bitcoin wallets via blockchain.info in 2013 or 2014 and retained two AES-encrypted backup files dated 28 February 2014 and 22 April 2013
Intersango Exchange Collapse: 2000 BTC User Funds Retained by Operator — Norman v. Strateman
Exchange custody
Blocked 2012
Intersango, a UK-based Bitcoin exchange co-founded by Amir Taaki and Patrick Strateman, ceased operations in 2012 after losing its banking relationship. At the
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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.

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