About 7.12 million Bitcoin, or 35.4 per cent of the network's total issued supply, now sits in addresses whose public keys are already visible on the blockchain, according to new data from on-chain analytics firm Glassnode — a potential target if quantum computers ever mature enough to break today's cryptography. The figure, published on 10 November, is the highest in the series Glassnode tracks.
The core finding is about visibility. Every Bitcoin wallet has a private key, which signs transactions, and a public key, which can be derived from it. Under the cryptography Bitcoin uses today, working backward from a public key to a private key is considered impractical. A sufficiently powerful quantum computer, running an algorithm known as Shor's algorithm, could in theory change that maths — and if that happens, any coin whose public key is already sitting on the blockchain becomes the low-hanging fruit.
Glassnode breaks the exposure into two main sources. Address reuse accounts for 25.8 per cent of supply, covering wallets where earlier transactions have already revealed the key, and balances held by exchanges account for 11.6 per cent. The exposed share has risen steadily: it stood at 24.8 per cent in early 2021, climbed to 30.2 per cent by May 2026 and 31.2 per cent by October 2026, before reaching the latest reading of 35.4 per cent.
Legacy P2PK outputs, an early transaction format that records the public key directly in the output script, hold approximately 1.71 million Bitcoin, and a significant share of those coins is attributed to Satoshi Nakamoto, Bitcoin's pseudonymous creator, whose early-mined coins have never moved. Taproot outputs also expose their public keys by design, since the tweaked public key serves directly as the address.
Glassnode is not the only firm seeing this. Independent data from ChainQuery puts exposed supply at around 35.6 per cent as of early November 2026, close enough to Glassnode's reading to suggest the figure is not a quirk of one firm's methodology. ChainQuery's own count, from a snapshot at block 975,029 on 8 November, puts 7.16 million Bitcoin at risk, split between about 1.94 million that are always exposed and 5.22 million exposed through reuse.
There is no quantum emergency, at least not yet. Quantum computers capable of breaking Bitcoin's current encryption standards do not exist today, and there is no settled timeline for when, or whether, such machines will arrive. The risk Glassnode is measuring is about what is sitting in the blast radius if the threat materialises, not a countdown to a known attack date — and Google's own estimates imply tens of millions of physical qubits would be needed, far beyond today's hardware.
The community has been preparing for this for years. The authors of BIP 360, a draft Bitcoin improvement proposal, describe a different attack path and propose pay-to-Merkle-root outputs through a soft fork, while a separate draft, BIP 361, proposes migration away from legacy signatures after a post-quantum output type becomes available. Both remain drafts, and the debate over how and when to move continues.
Glassnode co-founder Rafael Schultze-Kraft pointed to a straightforward fix for the largest bucket of exposure: moving coins from reused addresses to freshly generated ones eliminates the exposure tied to reuse. For holders, the practical advice is simple — do not reuse addresses, and move long-held coins to a fresh address if their public key has already been revealed by a previous spend.
The data lands at a nervous moment for the market. Bitcoin is trading around $73,700 to $74,700 after a hotter-than-expected US inflation report pushed traders to price in a possible Federal Reserve rate increase, US spot Bitcoin ETFs have recorded heavy outflows, and the Crypto Fear and Greed Index stands in Fear territory. The quantum figures do not explain the price action, but they add a longer-term question to a market already focused on the short term: how much of the world's most valuable cryptocurrency is, in principle, within reach of a machine that does not yet exist.
Figures in this post were checked at 11:06 PKT on Wednesday, 11 November 2026. This post is market news information only, not financial advice.
