A new report from digital asset manager CoinShares is rejecting the growing narrative that Bitcoin faces a looming quantum computing crisis, arguing that only a small portion of supply is actually at risk in a way that could move markets.
Saturday’s report disputed widely cited estimates suggesting that between 20% and 50% of all bitcoins could eventually be vulnerable to quantum key mining. Those figures, CoinShares said, blur the line between theoretical exposure and coins that could actually be compromised at scale.
CoinShares narrowed its focus to legacy pay-to-public-key (P2PK) addresses, where public keys are permanently visible on-chain and therefore easier targets if quantum computers are able to reverse them.
The company estimates that around 1.6 million BTC, or about 8% of the total supply, is in these older address types.
But CoinShares argued that the number of coins large enough to create an “appreciable market disruption” if stolen is much smaller: around 10,200 BTC. The rest, he said, are spread across more than 32,000 UTXOs averaging around 50 BTC each, making them much less attractive and requiring much more time to crack even under optimistic assumptions.
The key point is that most of the potentially exposed bitcoin is not in a handful of giant, juicy targets. It is dispersed across over 32,000 separate coin shards, with each shard averaging around 50 BTC.
A quantum attacker would have to decipher those fragments one by one to steal them, rather than breaking in in a single direction and making off with market-changing loot. That makes work slower, noisier, and less profitable, even assuming the attacker has unusually strong 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, quoted in the report, noted that Google’s Willow is a 105-qubit machine, while cracking keys would require millions of qubits.
Instead, the company supported a gradual transition toward post-quantum signatures, framing quantum risk not as an emergency but as a foreseeable engineering problem that Bitcoin can absorb over time.
Quantum fears are not new to bitcoin, but they have reappeared 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 distant and unproblematic, arguing that machines capable of cracking bitcoin cryptography are unlikely to exist for decades.
Critics respond that the real problem is not the timeline, but the lack of visible preparation, especially as governments and major technology companies begin to implement quantum-resistant systems.
Proposals like BIP-360 aim to introduce new wallet formats that could allow users to migrate gradually, but the debate has highlighted a growing gap between developers and increasingly institutional capital that wants a clearer long-term plan.
