Quantum Alliance Flags 6.4M BTC at Risk from Future Quantum Attacks

What happened: Nine blockchain companies have launched the Quantum Alliance, an open standards body focused on post-quantum security for blockchains. The group estimates that 6.4 million BTC—about 30% of the total supply—have exposed public keys and could be vulnerable to a future cryptographically-relevant quantum computer (CRQC), including approximately 1.1 million BTC attributed to Satoshi Nakamoto. There is disagreement among members about the timeline for quantum threats, with some citing 2028 as a possible inflection point, and debate over whether vulnerable coins should be frozen.

Why it matters: The formation of the Quantum Alliance marks the first coordinated industry response to the quantum computing threat, which, while not imminent, is now considered more plausible after a March 2026 Google Quantum AI paper lowered the estimated hardware requirements. The debate over freezing coins highlights unresolved tensions between technical security and Bitcoin’s foundational principle of seizure resistance. Notably, most founding members are infrastructure or altcoin projects, not Bitcoin Core developers, signaling a gap between the alliance and the Bitcoin protocol’s stewards.

Source: CoinDesk