Nearly 10% of Bitcoin’s total supply is considered “structurally insecure” due to discoveries in quantum computing, as their type of output reveals the public key by design, regardless of address management practices, according to data analytics platform Glassnode.
Totaling around 1.92 million Bitcoins (BTC), the group includes BTC from early Satoshi-era Pay-to-Public-Key (P2PK) exits, legacy multi-sig structures such as Pay-to-Multisig (P2MS) and modern Pay-to-Taproot (P2TR) exits, which reveal a public key or a public key equivalent by design, Glassnode wrote on Wednesday X publish.
Bitcoin creator Satoshi Nakamoto’s coins represent about 1.1 million or 5.5% of the vulnerable supply, followed by another 620,000 coins from the Satoshi era or 3.1% of the supply and about 200,000 coins or 1% of the supply on Taproot addresses.
The choice of how to implement PQC (post-quantum cryptography) and its on-chain implementation should remain separate from the question of what to do with coins that remain quantum vulnerable. However, these two things are often mixed up, and controversies about the second one often obscure discussions about the first one – ARK Invest
The findings highlight the need to implement a quantum-resistant pathway for Bitcoin, such as adopting BIP-360’s proposed Pay-to-Merkle-Root (P2MR) exit type, which seeks to remove Taproot’s quantum-vulnerable key consumption, although it does not itself add post-quantum digital signatures.
While 9.6% of the total supply remains structurally exposed, a significant portion of that exposure “could be reduced if wallet infrastructure, address standards and user behavior evolve,” Glassnode added.
However, this supply would only be vulnerable to quantum theft if quantum computers can crack Bitcoin’s Elliptic Curve Cryptography (ECC), which would require about 2,330 logical qubits and tens of millions to billions of quantum gates, according to White March paper announced by American investment manager Ark Invest.
Source: Glass node
Almost 70% of the Bitcoin supply is safe from the threats of quantum computing
Glassnode estimates that around 13.99 million Bitcoins, representing 69.8% of the total supply, remain unexposed to the threat of quantum computing, which is largely in line with figures from Ark Invest, which showed that 65% of the supply was secure, Cointelegraph reported in March.
However, the analytics service provider notes that around 4.12 million BTC, or 20.6% of the total supply, are “operationally insecure”, meaning that these coins are exposed due to key or address management issues.
Source: Glass node
Entity-level data show that some large corporate entities are exposed to shares. This includes 100% of BTC held by Franklin Templeton, WisdomTree and Robinhood, 99% of Bitcoin by neobank Revolut, 52% of Grayscale’s holdings and just 2% of Fidelity’s Bitcoin.
Related: Bernstein says the Bitcoin market is already priced in by quantum risk
Looking at crypto exchange tokens exposed, only about 5% of the BTC held on Coinbase is exposed, compared to 85% of Binance’s BTC and about 100% of holdings on the Bitfinex exchange.
To reduce exposure, exchanges and custodians are advised to reduce key reuse, improve address hygiene and plan to migrate to a quantum-resistant format to prepare for a future quantum breach, Glassnode wrote.
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