A new report from digital asset manager CoinShares pushes back against the growing narrative that Bitcoin faces a looming quantum computing crisis, arguing that only a small portion of supply is realistically at risk in a way that could move markets.
Saturday’s report challenged widely cited estimates suggesting that up to 20% to 50% of all bitcoins could eventually be vulnerable to quantum key mining. According to CoinShares, these numbers blur the line between theoretical exposure and coins that could actually be compromised on a large scale.
CoinShares has focused on legacy Pay-to-Public-Key (P2PK) addresses, where public keys are permanently visible on-chain and therefore easier targets if quantum computers become capable of reversing them.
The company estimates that around 1.6 million BTC – or around 8% of the total supply – is in these older address types.
But CoinShares argued that the number of coins large enough to create “appreciable market disruption” if stolen is much lower: around 10,200 BTC. The rest, he says, is spread across more than 32,000 UTXOs averaging around 50 BTC each, making them much less attractive and much longer to resolve, even under optimistic assumptions.
The key point is that most of the potentially exposed bitcoins are not found in a handful of giant, juicy targets. It is scattered across more than 32,000 separate pieces of coins, and each piece represents on average around 50 BTC.
A quantum attacker would have to break these pieces off one by one to steal them, instead of breaking into a single address and leaving with market-moving loot. This makes the work slower, noisier, and less profitable, even assuming the attacker has unusually powerful quantum hardware.
CoinShares said breaking Bitcoin’s cryptography would require fault-tolerant quantum systems about 100,000 times more powerful than today’s largest machines, putting the threat at least a decade away. Ledger CTO Charles Guillemet, cited in the report, noted that Google’s Willow is a 105-qubit machine, while cracking keys would require millions of qubits.
Instead, the company endorsed a gradual transition to post-quantum signatures, describing quantum risk not as an emergency, but as a predictable engineering problem that Bitcoin can absorb over time.
Quantum fears are not new to Bitcoin, but they have resurfaced in market conversations as prices falter and investors look for structural risks to blame.
In December, CoinDesk reported that most Bitcoin developers view quantum computing as a distant and unproblematic problem, arguing that machines capable of cracking Bitcoin’s cryptography are unlikely to exist for decades.
Critics counter that the real problem is not the timeline, but the lack of visible preparation, especially as governments and big tech companies begin to deploy quantum-resistant systems.
Proposals such as BIP-360 aim to introduce new wallet formats that could allow users to gradually migrate, but the debate has highlighted a growing gap between developers and increasingly institutional capital that wants a clearer long-term plan.
