On-chain analytics firm Glassnode has flagged that 31. 2% of the Bitcoin supply is associated with addresses that have exposed public keys, a condition that could become relevant if sufficiently powerful quantum computers ever emerge.
On-chain analytics firm Glassnode has flagged that 31.2% of the Bitcoin supply is associated with addresses that have exposed public keys, a condition that could become relevant if sufficiently powerful quantum computers ever emerge. The finding draws attention to a structural vulnerability in a portion of the Bitcoin network that has existed since the protocol’s earliest days.
What the 31.2% Figure Measures
Bitcoin addresses fall into several types, and not all of them keep the underlying public key hidden. Pay-to-public-key (P2PK) outputs, as well as any address that has already sent a transaction and therefore broadcast its public key to the network, have what researchers call an exposed public key. Glassnode’s analysis puts the share of circulating supply held in such outputs at 31.2%. For related coverage, see Bitcoin Options Market Signals Calm; On-Chain Data Warns Volatility.
The distinction matters because Bitcoin’s security model relies on two separate cryptographic layers. The first, a hash function, protects addresses that have never sent funds; the second, the elliptic-curve digital signature algorithm (ECDSA), protects the private key once the public key is known. An address with an exposed public key has already passed through the first layer, leaving only ECDSA standing between an attacker and the funds. For related coverage, see Bitcoin Options Market Faces Potential Volatility Amid Mixed Signals.
This is not a new observation. Some of the coins sitting in P2PK outputs date to 2009 and 2010, the Satoshi-era period when the protocol used that address format by default. The question of what happens to those coins as computing power advances has circulated among cryptographers and Bitcoin developers for years. Glassnode’s figure puts a specific scale on the exposure, which is useful for evaluating the scope of any future remediation effort. Separately, one of Bitcoin’s oldest wallets became active recently, a reminder that coins locked in early address formats remain a live topic for the network. For related coverage, see Remixpoint Bitcoin Treasury Shift Sells ETH and XRP.
Why Public-Key Exposure Connects to the Quantum Risk Discussion
Quantum computers capable of running Shor’s algorithm at scale could, in theory, derive a private key from a known public key. Current quantum hardware is orders of magnitude too limited to threaten ECDSA in practice, and no credible timeline for a cryptographically relevant quantum computer exists in the public record. Glassnode’s warning is therefore a risk-framing exercise, not an imminent threat alert.
The practical concern is a race condition: if a quantum computer capable of breaking ECDSA were built before Bitcoin migrated to a post-quantum signature scheme, the 31.2% of supply with exposed keys would be more vulnerable than the remainder. Coins in standard P2WPKH or P2TR outputs that have never been used to send funds would still benefit from the hash-function layer, buying additional time for an emergency migration. Glassnode has previously used on-chain data to separate structural signals from short-term noise in the Bitcoin market, and the quantum-exposure metric follows the same methodology: measure the actual state of the UTXO set rather than speculate.
What the Finding Means for Bitcoin Holders and the Network
For individual holders, the immediate implication is straightforward: coins held in addresses that have never broadcast a transaction, particularly native SegWit (bc1q) or Taproot (bc1p) outputs, retain the hash-function protection layer. Moving funds to a new, never-used address after each spend is standard Bitcoin hygiene and directly reduces exposure to this class of risk.
At the network level, a migration to post-quantum cryptography would require a soft or hard fork and broad developer and miner consensus, a process that would take years even if the timeline for quantum threats became clearer. The 31.2% figure gives protocol developers a concrete measure of how much of the supply would need to be considered in any such upgrade. Coins in exposed outputs whose owners are unreachable, including presumed lost coins and early miner rewards, complicate that calculus further.
The Bitcoin network’s difficulty adjustment and the incentive structure around mining remain unaffected by public-key exposure; the vulnerability, if it ever becomes material, would target specific UTXOs rather than consensus mechanics. On-chain data has increasingly become a primary tool for surfacing Bitcoin network risks before they become market events, and Glassnode’s quantum-exposure metric fits that pattern. The open question is whether Bitcoin’s development community will treat the 31.2% figure as a catalyst for accelerating post-quantum research or as a background concern to revisit when quantum hardware progresses further.
Additional source references: source document 1, source document 2.
Disclaimer: This article is for informational purposes only and does not constitute financial or investment advice. Cryptocurrency and digital asset markets carry significant risk. Always do your own research before making decisions.
