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1. Quantum Computing Bitcoin Risk Prompts a New Industry Alliance
Nine crypto companies launched the Quantum Alliance on Thursday, October 15, to coordinate preparations for the day quantum computers can break the cryptography that protects blockchains. The group estimates that 6.4 million bitcoin, or 30.2% of the supply, sits at addresses whose public keys are already exposed. Members agree on the danger but disagree on its timing and on whether vulnerable coins should be frozen.
The quantum computing bitcoin debate has long centered on a single question: what happens to coins that cannot be moved to safer addresses because their owners are gone or unreachable? The alliance gives that discussion an organizational home, with the stated aim of developing shared security standards for bitcoin, Ethereum and other blockchains.
No machine in existence is powerful enough to carry out such an attack today, and the coins at issue cannot be stolen at present. The new group's premise is that the time to plan is before the capability exists, not after.
2. How Could a Quantum Computer Threaten Bitcoin?
A sufficiently capable quantum computer could work out the secret key behind a wallet once it knows that wallet's public key. With the secret key in hand, an attacker could sign transactions and move the funds as though they were the owner.
That is why public key exposure matters. The Quantum Alliance counts 6.4 million BTC, about 30.2% of all bitcoin in existence, at addresses where the public key is already visible. Those holdings are the most obvious targets, because an attacker would not need to race against a transaction in progress; the information required is already on the public record.
The debate extends to the best-known holdings of all. Discussion of the issue frequently returns to the roughly 1.1 million BTC associated with Satoshi Nakamoto, bitcoin's pseudonymous creator, and to millions of other coins that have not moved for years. If quantum machines eventually become strong enough to defeat current bitcoin security, the question of who would be in a position to take those coins becomes real.
3. Who Would Get Satoshi's Coins?
Christopher Smith, chief executive of Quantus, a layer-1 blockchain built to resist quantum attacks, argues that the first party to build a cryptographically relevant quantum computer would likely end up with those coins. He added that this would probably happen with the approval of a national government.
His comment on the likely outcome was candid: "Hopefully it's a government that likes bitcoin." The remark captures a concern that runs through the discussion, which is that the power to break bitcoin's signatures could be concentrated in a small number of well-resourced states or companies, whatever the preferences of the bitcoin community.
It also illustrates why the issue is treated as one of network security rather than a narrow technical upgrade. If the coins held by long-dormant addresses were claimed by whoever built the first machine, the effect on confidence in the asset could extend well beyond the holders directly affected.
4. When Will Quantum Computers Be Powerful Enough?
Members of the alliance do not agree on a date. Bryn Bennett, chief revenue officer of The Vault, said that nobody knows when the moment will arrive but that the estimates keep falling, which in his view makes the risk something to plan for now. For custodians, he said, the practical question is whether they could migrate in time if the threat arrived earlier than expected.
Richard Carback, chief technology officer of Postquant Labs, is more pessimistic about the timeline. He disagrees with the more distant forecasts and regards 2028 as a realistic date for a machine able to break today's cryptography.
Recent research has lowered the estimates of the computing power needed to attack bitcoin and Ethereum. Even so, no existing machine can break either network's cryptography, and the forecasts remain disputed among specialists. The disagreement inside the alliance mirrors the uncertainty in the wider field.
5. Should Vulnerable Bitcoin Be Frozen?
The most contentious issue is whether developers should freeze vulnerable holdings before quantum computers can reach them. The idea has attracted attention from prominent figures. Changpeng Zhao, the founder of Binance, has suggested freezing Satoshi's 1.1 million BTC if the coins remain untouched while quantum technology advances, and the bitcoin developer Jameson Lopp has proposed restrictions on vulnerable coins to prevent theft.
Critics respond that freezing anyone's bitcoin violates a founding principle of the network, namely that no one can confiscate holdings. On that view, a rule that disables coins, even for protective reasons, sets a precedent that undermines the property rights the system was built to guarantee.
Carback favors moving coins rather than freezing them. Bennett pointed to a different obstacle, which is authority. Custodians look after the assets of their clients, not abandoned ones, so no party clearly owns the problem. In his words: "Nobody owns that issue, and that's the problem."
Bennett also argued that a freeze is a matter of bitcoin network governance, not something the industry can decide for itself, and he warned that any freeze would trade quantum risk for a precedent on property rights and network neutrality.
6. What Would Quantum-Resistant Bitcoin Require?
Making bitcoin resistant to quantum attack would require replacing the digital signatures that authorize transactions. That change cannot be made by any single party. It needs agreement among developers, miners, wallet providers, exchanges and users, a coordination task that bitcoin's decentralized structure makes slow by design.
On the question of cost, Bennett was blunt: "Nobody has a credible single number, and anyone offering one is guessing." He said the main expense lies in coordinating wallets, exchanges, custodians and protocol developers, not in the cryptography itself.
There is also a capacity question. Replacement signatures would be larger than the ones in use now, which could raise fees or reduce the number of transactions a blockchain can process. Researchers are working on methods to limit that effect, but the trade-off is one of the practical constraints on any migration.
7. Who Is in the Quantum Alliance and What Will It Publish?
The alliance brings together nine crypto companies. Members include Hacken, the Midnight Foundation associated with Charles Hoskinson, Quantus and Postquant Labs. Its stated purpose is to set shared security standards across bitcoin, Ethereum and other blockchains.
Its first work is expected to be practical. The group plans to publish shared security tests and guidance for migrating existing networks to quantum-resistant systems. Common tests would give projects a way to measure their exposure, and common guidance could shorten the time needed to move once a decision is made.
The alliance will not settle the freeze question, since that depends on network governance rather than on any industry body. Its role is to prepare the technical groundwork so that whatever the community decides can be carried out without delay.
8. Trust Proposals and the Unresolved Question
One idea for protecting at-risk coins comes from Carback. He proposes placing vulnerable coins in a trust so that owners who can prove ownership are able to recover their funds. The approach would aim to protect legitimate holders without simply confiscating or abandoning the coins.
Whether any such arrangement would be acceptable to the wider bitcoin community is unclear. The underlying tension is that protecting bitcoin from quantum attack may require changing the rules, and the appeal of bitcoin has always rested in part on the rules not changing.
For now, the alliance's launch shows that parts of the industry no longer treat the threat as a distant abstraction. The timeline is contested, the cost is unknown and the governance path is unsettled, but a group of companies has agreed that preparation should begin before a capable machine exists.
9. Why Coordination Is Harder Than the Cryptography
The technical part of the problem is, in principle, understood. Cryptographers have been working for years on signature schemes designed to withstand quantum attack, and replacing one scheme with another is a familiar kind of engineering. The difficulty is that a blockchain has no central operator who can order a change and see it applied across every participant.
In the case of bitcoin, a new signature type would have to be accepted by the software that nodes run, supported by the wallets that hold keys, handled by exchanges and custodians, and adopted by individual holders who must move their own coins. Each group has different incentives and different timetables, and the process only works if enough of them act before the threat becomes real.
This is the reason several alliance members describe the work as organizational rather than purely scientific. A shared set of tests lets projects compare notes on how exposed they are, and shared guidance lets custodians plan the sequence of moving client assets. Without them, each firm would have to solve the same problems on its own, and the weakest link would set the level of risk for everyone.
The exposure figure also helps frame priorities. Because the alliance puts the share of supply with visible public keys at 30.2%, the migration is not an all-or-nothing project but one that can be staged, beginning with the coins most at risk. How that staging would work depends on the unresolved choices about freezing, moving and recovering coins.
10. What Happens Next?
The immediate milestone is the alliance's first publication of shared security tests and migration guidance, for which no date has been given. Beyond that, the decisive steps will come from the developers and communities that govern each network, which have yet to agree on whether to freeze, move or leave vulnerable coins in place.
Watchers will also follow the research on how much computing power an attack on bitcoin and Ethereum would require, since further falls in those estimates would strengthen the case of those, like Carback, who see 2028 as realistic.