Quantum Alliance forms as group says 6.4 million bitcoin have exposed keys
In brief
- Nine crypto companies unveiled the Quantum Alliance to build common blockchain security standards.
- 6.4 million BTC, or 30.2% of supply, have exposed public keys, the alliance estimates.
- Those coins can't be stolen this way today, the alliance said.
- Richard Carback, Postquant Labs CTO, named 2028 as a realistic date for a capable machine.
- Freezing vulnerable coins remains disputed among Zhao, Lopp, Carback and Bennett.
Who's in and what's at risk
CoinDesk named four of the alliance's members: Hacken, Charles Hoskinson's Midnight Foundation, Quantus and Postquant Labs. The group plans to publish common security tests and migration guidance.
The worry itself is simple. Future quantum computers could derive a wallet's secret key from its publicly visible key, and that would let attackers steal funds. Recent research has reduced estimates of the computing power needed to attack bitcoin and Ethereum, but no existing machine can break their cryptography (and the timelines are still disputed).
Experts don't agree on the clock
Quantus CEO Christopher Smith said whoever builds a cryptographically relevant quantum computer first could take vulnerable coins, potentially with government backing. That's his speculation. Nobody has built that machine yet.
Postquant Labs CTO Richard Carback said he believes 2028 is a realistic date for a machine capable of breaking today's cryptography. Bryn Bennett, chief revenue officer at The Vault, wouldn't commit to a year.
“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.”
The freeze question
Then there's Satoshi.
Who'd get Satoshi Nakamoto's estimated 1.1 million bitcoin if quantum computers break its security has been debated for some time. Binance founder Changpeng Zhao has suggested freezing those coins if they stay untouched as quantum tech advances, and Bitcoin developer Jameson Lopp has proposed restrictions on vulnerable coins to prevent future theft. Critics argue that freezing anyone's bitcoin goes against the promise that nobody can confiscate it.
Carback said he'd prefer vulnerable coins be moved rather than frozen. Bennett said freezing is a governance decision for the Bitcoin network, not for the industry.
Migration won't be simple either. Making bitcoin quantum-resistant means replacing the digital signatures that authorize transactions, and that needs agreement among developers, miners, wallet providers, exchanges and users. The replacement signatures could also take up more space on the blockchain (potentially raising fees or reducing throughput), though researchers are working to limit that impact. Bennett said nobody has a credible single figure for what migration costs; in his view, the real cost is coordination.
Frequently asked questions
How could quantum computers threaten bitcoin?
The concern is that future quantum computers could derive a wallet's secret key from its publicly visible key, letting attackers steal funds. The Quantum Alliance estimates 6.4 million BTC, or 30.2% of supply, have exposed public keys. It said those coins can't be stolen this way today because no existing quantum computer is powerful enough.
When will quantum computers be able to break bitcoin's cryptography?
Nobody knows, and the timelines are disputed. Postquant Labs CTO Richard Carback said he believes 2028 is realistic, while The Vault's Bryn Bennett said nobody knows the date but estimates keep falling. Recent research has reduced estimates of the computing power needed to attack bitcoin.
What would it take to make bitcoin quantum-resistant?
It would mean replacing the digital signatures that authorize transactions, which needs agreement among developers, miners, wallet providers, exchanges and users. The new signatures could take more blockchain space, potentially raising fees or reducing throughput. Bennett said the real cost is coordination.
