TL;DR
- More than 6 million BTC, or 31.2% of circulating supply, sit behind public keys already visible onchain, according to Glassnode co-founder Rafael Schultze-Kraft.
- Exposed supply rose by 222,000 BTC since May, with exchanges accounting for 123,000 BTC and holding 1.79 million BTC behind visible public keys.
- The figures measure public-key exposure rather than active compromise, and no practical attack capable of breaking Bitcoin wallet keys has been demonstrated.
Bitcoin now has more than 6 million BTC sitting behind public keys already visible onchain, according to Glassnode co-founder Rafael Schultze-Kraft. In an October 8 update, he said the exposed amount represents 31.2% of circulating supply, around 5 to 6 percentage points above the 2023 low. The figures describe public-key exposure, not an active compromise or proof that those coins can currently be stolen. No practical attack capable of breaking Bitcoin wallet keys has been demonstrated.
6.26M #BTC, or 31.2% of supply, sits behind a public key that is already visible on-chain.
At least that much would have to move in a migration to addresses whose keys are still hidden behind a hash.
The share is up from 24.8% in early 2021 and back at 2016 levels.
🧵 1/6 https://t.co/a98gA5ybek pic.twitter.com/mpQw99i9ap
— Rafael (@n3ocortex) October 8, 2026
Public-Key Exposure Has Risen Since May
The exposed total has increased by 222,000 BTC since Glassnode’s May report, even as overall Bitcoin supply grew by only 64,000 BTC over the same period. Exchanges accounted for 123,000 BTC of that increase and now hold 1.79 million BTC behind visible public keys. The divergence suggests that public-key exposure has expanded materially faster than Bitcoin’s supply itself, concentrating attention on how large custodial balances are structured onchain. Because the metric tracks whether a public key is visible, it should not be read as an estimate of coins that are immediately vulnerable to theft today. The data adds a fresh measurement to the quantum-risk debate around dormant and exposed Bitcoin.
Exposure varies sharply across major entities. Coinbase has 10% of its tracked BTC exposed under the methodology, compared with 83% at Binance. Fidelity holds about 375,000 BTC with just 2% exposed, while Grayscale stands at 49%, Revolut at 99% and Robinhood at 100%. U.S., U.K. and El Salvador government holdings show no exposure under the same methodology. Those differences show that the 31.2% network-wide figure is not evenly distributed and depends heavily on address practices and wallet structures. That distinction also matters in the broader discussion over preparing Bitcoin for quantum computing.
Public keys can become visible through address reuse or appear directly in certain output types, including early pay-to-public-key outputs and Taproot. A sufficiently capable quantum computer, or a hypothetical mathematical breakthrough, could potentially derive private keys from exposed public keys. The warning has gained urgency as researchers discuss whether AI could accelerate discoveries in cryptanalysis, although no such breakthrough has been demonstrated. The current issue is therefore preparedness for a future cryptographic threat, not evidence that Bitcoin’s security has already failed. The growing exposed balance keeps post-quantum migration and legacy-address policy central to the network’s long-term security debate.
