30% of Bitcoin Already Exposed to Quantum Attack Risk, Glassnode Reports
According to a research report released by blockchain analytics firm Glassnode, over 30% of all Bitcoin in circulation—approximately 6.04 million BTC worth over $469 billion—has had its public key exposed on-chain, making it theoretically vulnerable to a future quantum computer attack. The study categorizes exposure into two types: structural (1.92 million BTC) from script designs like pay-to-public-key and Taproot outputs that inherently reveal public keys, and operational (4.12 million BTC) caused by address reuse. Exchanges account for roughly 40% of operationally exposed Bitcoin (1.66 million BTC), with significant variance across platforms: Coinbase shows only 5% exposure, while Binance and Bitfinex display 85% and 100% exposure respectively. The analysis notes that sovereign holdings from the US, UK, and El Salvador show zero quantum risk. The findings come amid accelerating quantum computing advances and ongoing discussions within the Bitcoin community about protocol-level defenses, including BIP-360 and proposals to freeze unmigrated coins. Glassnode emphasizes the report should be viewed as a baseline for improving wallet hygiene and custody design, not as an immediate threat.
Key facts
- 6.04 million BTC (30.2% of total supply) has exposed public keys, per Glassnode.
- Structural exposure: 1.92M BTC from script designs that reveal keys.
- Operational exposure: 4.12M BTC from address reuse, 40% held by exchanges.
- Coinbase only 5% exposed; Binance 85%, Bitfinex 100%.
- Quantum attack feasibility depends on 'Q-Day' estimated between 2030-2032.