30% of Bitcoin's Supply Already Has Its Public Key Exposed to Quantum Risk

A new Glassnode analysis maps Bitcoin's quantum-exposed supply with precision: 6.04M BTC — 30.2% of issued supply — already has its public key visible on-chain, making it theoretically targetable by a sufficiently capable quantum computer without waiting for the owner to move the coins. The remaining 13.99M BTC shows no public-key exposure at rest.

The exposure breaks into two distinct buckets. Structural exposure accounts for 1.92M BTC (9.6%): outputs where the script type itself reveals the public key by design — early P2PK coins from the Satoshi era, legacy bare multisig, and modern Taproot outputs. Some of this cohort may be effectively immobile, meaning it cannot voluntarily migrate to safer address structures without a contentious protocol-level response. Operational exposure is the larger share at 4.12M BTC (20.6%), driven by address reuse, partial spending, and custody…