More than 6.26 million BTC—31.2% of circulating supply—now sits behind public keys visible onchain, according to a new update from Glassnode co-founder Rafael Schultze-Kraft published on October 8, 2026.
The figure measures public-key exposure rather than active compromise, meaning no practical attack that could break Bitcoin wallet keys has been demonstrated. Still, the exposed share has climbed from 24.8% in early 2021 and is back at levels last seen in 2016. Since Glassnode's May report, exposed supply increased by 222,000 BTC, even though total Bitcoin supply grew by only 64,000 BTC over the same period. Exchanges added 123,000 BTC to that exposed pool and now hold 1.79 million BTC behind visible public keys.
The exposure is uneven across major custodians. Coinbase has 10% of its tracked BTC exposed, while Binance stands at 83%. Fidelity holds about 375,000 BTC with only 2% exposed, Grayscale is at 49%, Revolut at 99% and Robinhood at 100%. U.S., U.K. and El Salvador government holdings showed no exposure under Glassnode's methodology.
Schultze-Kraft framed the data as relevant to the quantum-risk debate. Public keys can become visible through address reuse, early pay-to-public-key outputs, or Taproot. A sufficiently advanced quantum computer could theoretically derive private keys from exposed public keys, but no such breakthrough has been demonstrated. The report therefore positions the growing exposed balance as a long-term migration and legacy-address policy issue, not evidence that Bitcoin's security has already failed.
