A Decade Ago, a $6.3 Billion Hack Would Have Sunk Binance & BTC, Bitwise CIO Says

Proof-of-reserves became standard practice across exchanges after FTX's 2022 collapse exposed how little customers knew about what backed their balances, with Merkle-tree snapshots as the first generation. Binance's zero-knowledge method is a cryptographic step beyond that, letting any of its 335 million users check one-to-one backing for ten major tokens without exposing individual account data. The October 29 hack and the October 31 snapshot gave that system its first real stress test.

Withdrawals reopening let customers pull $10.97 billion over roughly 46 hours, with hourly outflows peaking at $936 million before Binance led exchanges with $2.3 billion in net inflows as confidence returned. Binance says 98% of the tokens drained in the hack have been replenished, meaning most holders can now move funds freely again. The remaining 2% leaves a defined group of users still waiting on restitution rather than a fully closed case.

A reserves snapshot proves assets existed at a point in time; Binance itself calls this no solvency audit, so it says nothing about liabilities, obligations elsewhere, or the fact that one company still controls the keys behind the ten verified tokens. Reporting that insurance may cover little of the $6.3 billion loss sharpens that gap: if a state-backed attack of this scale leaves the exchange largely self-insured, the real backstop for depositors is Binance's own balance sheet, not a third party.

The unresolved 2% of impacted tokens is the concrete marker to watch, since full replenishment would close the restitution question that proof-of-reserves alone cannot answer. Equally telling will be whether net flows settle after the swings between $5.28 billion in outflows and $2.3 billion in inflows, or whether withdrawal pressure resumes once more users test the restored system. Any insurer determination on the $6.3 billion claim would also clarify who ultimately absorbs this loss.