A growing narrative that bitcoin faces an imminent quantum computing crisis is being challenged by a new report from digital asset manager CoinShares, which argues that only a small fraction of bitcoin supply is realistically exposed in a way that could meaningfully impact markets.
The firm’s central argument is that potentially vulnerable bitcoin is not concentrated in a few large, high-value targets. Instead, it is spread across tens of thousands of separate wallets, making large-scale exploitation far more difficult, slower, and less economically attractive than commonly assumed.
CoinShares, the world’s fourth-largest manager of digital asset exchange-traded products behind BlackRock, Grayscale, and Fidelity, estimates it holds a 34% share of the EMEA market and managed more than $10 billion in assets as of September 2025.
In its report, published Saturday, CoinShares pushed back against widely cited estimates suggesting that between 20% and 50% of bitcoin supply could eventually be vulnerable to quantum-enabled key extraction. According to the firm, those figures conflate theoretical exposure with coins that could plausibly be compromised at scale.
Instead, CoinShares focused on legacy Pay-to-Public-Key (P2PK) addresses, where public keys are permanently visible on-chain and therefore more exposed if sufficiently powerful quantum computers were to emerge. Roughly 1.6 million BTC — about 8% of total supply — remains in these older address types, the report said.
However, the firm argued that the portion capable of causing “appreciable market disruption” if stolen is far smaller, at roughly 10,200 BTC. The remainder is distributed across more than 32,000 individual unspent transaction outputs (UTXOs), each averaging about 50 BTC. This dispersion significantly reduces their attractiveness to an attacker.
Rather than breaching a single wallet and extracting a market-moving sum, a quantum attacker would need to compromise thousands of separate coin fragments one by one. Even under optimistic assumptions about quantum capabilities, CoinShares said, such an effort would be slower, noisier, and far less profitable.
The report also emphasized the technological gap between today’s quantum hardware and what would be required to threaten bitcoin’s cryptography. CoinShares estimated that fault-tolerant quantum systems roughly 100,000 times more powerful than existing machines would be needed, placing any credible threat at least a decade away. Ledger CTO Charles Guillemet, cited in the report, noted that Google’s Willow system currently operates at 105 qubits, while key extraction would require machines with millions of qubits.
Rather than framing quantum computing as an emergency, CoinShares described it as a foreseeable engineering challenge. The firm endorsed a gradual migration toward post-quantum signature schemes that bitcoin could adopt over time without disrupting the network.
Concerns about quantum risk are not new, but they have resurfaced as bitcoin prices have weakened and investors search for deeper structural explanations. In December, CoinDesk reported that most bitcoin developers consider quantum computing a distant, largely theoretical issue, with machines capable of breaking bitcoin’s cryptography unlikely to exist for decades.
Skeptics argue that the greater risk lies not in the timeline, but in the lack of visible preparation, particularly as governments and major technology firms begin deploying quantum-resistant systems. Proposals such as BIP-360, which would introduce new wallet formats enabling gradual migration, reflect that tension and highlight a widening gap between developer caution and institutional investors seeking clearer long-term assurances.
