CoinShares report argues only 8% of Bitcoin is realistically Quantum-vulnerable, not 34%

Feb 9, 2026

CoinShares published research challenging estimates that 20-50% of Bitcoin faces quantum computing risk, arguing only approximately 1.6 million BTC in legacy P2PK addresses—roughly 8% of supply—is realistically vulnerable. This contradicts Ark Invest and Unchained's March 2026 report estimating 35% of Bitcoin supply sits in theoretically vulnerable address types. CoinShares contends that breaking Bitcoin's cryptography would require quantum computers 100,000 times more powerful than today's systems, which currently demonstrate only 24-28 logical qubits versus the 6,000 needed. The firm narrows the true market-disruption risk to just approximately 10,200 BTC concentrated enough to cause meaningful price impact, with most vulnerable coins likely lost and unmovable.

Estimates of Bitcoin supply exposure and the Satoshi coins question

▪Satoshi Nakamoto's estimated 1.1 million BTC is spread across roughly 22,000 separate addresses at about 50 BTC each
▪Approximately 65% of Bitcoin's supply is held in address types where the public key has never been revealed
▪The Ark Invest/Unchained report estimates approximately 1.7 million BTC sits in P2PK addresses overall
▪Ledger's Donjon research team estimated roughly 25% of Bitcoin's supply by value has exposed public keys
▪A 2025 Chaincode Labs study estimated 6.26 million BTC could be exposed due to reused public keys
▪The Ark Invest/Unchained March 2026 report estimates approximately 35% of Bitcoin's total outstanding supply sits in theoretically vulnerable address types

Perspective of CoinShares

▪CoinShares challenges estimates that 20% to 50% of Bitcoin faces quantum computing risk
▪CoinShares calculates that roughly 8% of Bitcoin's supply faces realistic quantum vulnerability
▪CoinShares estimates only approximately 1.6 million BTC in legacy P2PK addresses is realistically targetable by quantum computers

Perspective of Ark Invest and Unchained

▪Ark Invest and Unchained estimate about 5.2 million BTC sits in reused or P2TR addresses that are migratable if holders act
▪Ark Invest and Unchained estimate that approximately 35% of Bitcoin's total outstanding supply sits in theoretically vulnerable address types