Quantum Alliance forms amid warnings 6.4 million bitcoin face future quantum threat

Who gets Satoshi Nakamoto’s 1.1 million bitcoin, and, for that matter, millions more that are at risk if quantum computers become powerful enough to break the security protecting it, has been a topic of intense debate for quite some time.

Christopher Smith, CEO of quantum-resistant layer-1 blockchain Quantus, believes whoever develops that technology first could take those tokens worth billions, potentially with government backing.

“The most likely scenario is that whoever gets the first CRQC (Cryptographically Relevant Quantum Computer) will take them, probably with the blessing of whichever national government,” Smith told CoinDesk. “Hopefully it’s a government that likes bitcoin.”

The security researcher and protocol engineer’s warning comes as nine crypto companies unveiled the Quantum Alliance on Thursday to develop common security standards for bitcoin, Ethereum and other blockchain networks.

The concern is that future quantum computers could reverse-engineer a wallet’s publicly visible key to uncover its secret key, allowing attackers to steal funds. The Alliance estimates that 6.4 million bitcoin, or 30.2% of the supply, have public keys already exposed. Those coins, it clarified, cannot be stolen this way today because no existing quantum computer is yet powerful enough.

The first question many are asking today is when quantum computers will actually be a threat to bitcoin. Bryn Bennett, chief revenue officer at The Vault, responded: “Nobody knows the date, but the estimates keep falling, and the risk is one we can already plan for. The question for custodians isn’t whether the date is 2028 or 2035; it’s whether you can migrate in time if it arrives early.”

Richard Carback, chief technology officer of Postquant Labs, disagreed, saying he believes 2028 is a realistic date for a machine capable of breaking today’s cryptography.

Recent research has reduced estimates of the computing power needed to attack bitcoin and Ethereum. But no existing machine can break their cryptography, and predictions about when one might arrive remain disputed.

The prospect of those BTC tokens being stolen raises yet another difficult question: should developers freeze vulnerable assets, such as Bitcoin holdings, before quantum computers can reach them? Carback says he prefers that they be moved rather than frozen, while Bennet sees a different problem.

“Nobody owns that issue, and that’s the problem,” Bennett told CoinDesk. “A custodian protects its clients’ assets, not abandoned ones. Freezing coins is a governance decision for the Bitcoin network, not for the industry.”

“Any freeze would trade quantum risk for a precedent on property rights and neutrality,” he added.

The debate has been ongoing. Binance founder Changpeng Zhao suggested freezing Satoshi’s estimated 1.1 million bitcoin if the coins remain untouched as quantum technology advances. Bitcoin developer Jameson Lopp has also proposed restrictions on vulnerable coins to prevent future theft. But critics argue that freezing someone’s bitcoin goes against the promise that no one can confiscate it.

Making bitcoin quantum-resistant would mean replacing the digital signatures used to authorize transactions. That requires agreement among developers, miners, wallet providers, exchanges and users.

“Nobody has a credible single number, and anyone offering one is guessing,” Bennett said of the cost. “The real cost isn’t the cryptography; it’s coordinating wallets, exchanges, custodians and protocol developers.”

The replacement signatures could also take up more space on the blockchain, potentially increasing fees or reducing the number of transactions bitcoin can process. Researchers are already working on ways to limit that impact.

The Quantum Alliance, whose members include Hacken, Charles Hoskinson’s Midnight Foundation, Quantus and Postquant Labs, plans to publish common security tests and guidance for moving existing networks to quantum-resistant systems.

Carback also proposed placing vulnerable coins in a trust, allowing owners who can prove ownership to recover their funds. For bitcoin holders, the unresolved question is whether the network can protect their money without changing the rules that made the number one cryptocurrency so appealing in the first place.