On May 7, 2019, Binance's hot wallet was hacked for about 7,000 Bitcoins, later rejecting Bitcoin reorganization
On May 7, 2019, Binance's hot wallet was hacked for about 7,000 Bitcoins, valued at around $40 million at the time, accounting for about 2% of its Bitcoin reserves. The attackers bypassed withdrawal risk controls through phishing, trojans, and multiple accounts, triggering an alert after a single transfer, leading the platform to suspend deposits and withdrawals while trading continued.
Jeremy Rubin, a core contributor to Bitcoin, publicly suggested that disclosing the stolen private keys or a subset could coordinate a zero-cost reorganization of the blockchain to reverse the theft. CZ stated that this idea was not initially proposed by the platform, and while the team discussed it, the external perception of the "discussion" itself was viewed as a mistake.
The next day, he confirmed that they would not pursue reorganization: it could damage Bitcoin's reputation and lead to network and community splits, miners would find it hard to coordinate, and it conflicted with the premise of decentralization. At that time, the community's debate over reorganization was more heated than the theft itself.
The losses were covered by the User Security Asset Fund (SAFU) established in 2018, funded by 10% of trading fees. CZ later wrote that the scale of about 7,000 Bitcoins was close to a quarterly burn from a year prior, and the proportion of cash reserves at that time was already lower than earlier decisions to fill gaps with their own funds.
User accounts were not recorded as losses; the platform used reserves to separate exchange risks from on-chain irreversible settlements. The stolen coins did not return to the original address due to reorganization, and subsequent flows were tracked according to normal UTXO.
In market mechanics, what was sold was centralized custody for instant withdrawals, and what was bought was reserves hedging against hot wallet theft. Funds were supplemented to user liabilities from SAFU and company cash, rather than purchasing a historical rewrite from the entire network's hash power; beneficiaries were users holding coins who did not have to bear the risk of chain forks, while the pressured party was the exchange treating the hot wallet as the final settlement layer. The event was driven by governance choices after the theft, rather than a single-day price fluctuation.
Source: Public Information
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This issue in 2019 placed two outcomes on the same table: rewriting the ledger or recognizing liabilities with fiat currency reserves. Rubin's proposal technically turned the theft into a coordinated miner vote, which CZ rejected because Binance does not have the final interpretation rights over Bitcoin, only user liabilities. Once reorganization sets a precedent, the next theft will demand the same political mobilization.
The capital path is that the fee collection is preemptively deposited into SAFU, transferring low-probability large losses from user accounts to the platform or liabilities. The hot wallet theft proved that custody itself is a single point of failure, while reserves demonstrated the platform's willingness to purchase "non-consensus" reputation with equity value. Two years later, industry insurance and reserve disclosures have followed this path rather than the reorganization route.
Comparable cases include the 2016 Ethereum fork for The DAO and traditional banks using deposit insurance instead of rollback liquidation systems. The Bitcoin community views DAO-style forks as oppositional; if exchanges strongly push for them, they will lose the neutrality of the settlement layer. The industry phase is that exchanges now require a scale greater than the coordination ability of a single miner alliance, and on-chain governance can no longer convene for a single company.
Structural judgments belong to self-restraint before regulatory changes, fundamentally separating the settlement layer from the application layer. The mechanism is that whoever can alter history owns the currency, and whoever can only write reserves only owns customers; leaving theft to UTXO and gaps to the fund retains pricing power on the longest chain.
ABAB News · Cognitive Laws
Those who can alter the ledger own the currency; those who can only write reserves own the customers.
Discussing reorganization itself can harm consensus more than the theft.
The fund accumulated from fees is the toll for centralization against irreversible settlements.