30% of Bitcoin Supply Has Exposed Public Keys — Exchanges Are the Weakest Link, Glassnode Finds

Glassnode data reveals that roughly 6.04 million Bitcoin — 30.2% of circulating supply — sit in wallets with publicly visible cryptographic keys, making them theoretically vulnerable to a future quantum-computing attack. The exposure is not evenly distributed: exchanges hold the worst-managed balances, with about half of all exchange-held Bitcoin classified as exposed, versus less than 30% of non-exchange supply.

The breakdown is stark at the individual platform level. Binance has 85% of its labeled Bitcoin balances exposed, placing over $34 billion of customer assets in the at-risk category. Bitfinex, Crypto.com, and Gemini each sit at 100% exposure. Coinbase stands out as the clear outlier, with just 5% exposure across its reserves. Government wallets tied to the US, UK, and El Salvador show near-zero exposure, with safety rates above 99%.

Glassnode separates the vulnerable supply…