Coinbase said in a November 4 security explanation that it was not affected by the reported Binance hot-wallet incident and that more than 99% of customer assets were held in cold storage. The source gives no year for the explanation. Coinbase also described distributed signing keys, withdrawal limits, anomaly detection and emergency controls that can stop transaction signing.
The storage figure is Coinbase’s stated practice, not a guarantee that every customer balance is protected from every risk. Account takeovers, fraud, software defects and legal restrictions remain separate risks. Distributed keys can prevent one compromised system from authorising a large transfer only if the rules governing them are properly implemented.
