A coalition of nine blockchain organizations launched the Quantum Alliance on October 15 in Lisbon to develop open standards for protecting cryptocurrency networks, wallets and infrastructure from future quantum computing threats. The group estimates that between 6.04 million and 6.4 million bitcoin, or about 30.2 percent of the total supply, already have public keys visible on the blockchain that sufficiently powerful quantum machines could one day exploit.

That total includes an estimated 1.1 million bitcoin linked to early holdings associated with Bitcoin’s creator. The alliance stresses that no quantum computer currently exists with the capability to derive private keys from those public keys or move the funds. The concern centers on the long-term possibility that machines running Shor’s algorithm could break the elliptic-curve digital signatures that secure ownership today.

Members and Mandate

Founding contributors include Quantus, American Fortress, Intmax, Keystone, Midnight Foundation, Postquant Labs, Abelian, The Vault and Hacken. The alliance will not create a new blockchain. Instead it plans to publish publicly available criteria for evaluating quantum readiness, security testing guidelines and migration pathways that individual networks can adopt.

Work is organized into four areas: moving existing funds and keys to stronger cryptography, assessing post-quantum zero-knowledge systems, strengthening wallet security practices, and ensuring compatibility across different chains. The structure draws from the open, consensus-driven model used by the Internet Engineering Task Force rather than decisions controlled by any single company or token holder.

Why Public Keys Create Exposure

Bitcoin wallets prove ownership through digital signatures. When certain addresses spend coins, the corresponding public keys become permanently visible on the ledger. Classical computers cannot reverse those public keys to recover private keys in any practical timeframe. Advanced quantum systems, however, could theoretically perform that calculation once they reach sufficient scale and reliability.

The alliance’s estimate of 6.04 million to 6.4 million exposed bitcoin represents coins already in that state. Experts note that additional public keys may exist outside the blockchain itself, including in hardware devices, partially signed transactions, logs and backups, which could expand the potential surface.

Timeline Estimates and Technical Progress

Postquant Labs co-founders developed a Quantum Doom Clock that tracks progress in physical qubits. Their model identifies roughly 856,000 physical qubits as a threshold and points to March 2028 as an early possible window for a machine capable of threatening current cryptocurrency cryptography. Other researchers place the more likely timeframe in the 2030s. The clock is presented as a monitoring tool rather than a firm prediction of an attack.

Recent research has added urgency. Google Quantum AI reported results from its Willow processor using a technique called magic state cultivation that reduced errors by a factor of 40 and achieved 99.99 percent accuracy in specialized quantum states needed for larger systems.

Richard Carback, chief technology officer at Postquant Labs, views 2028 as a realistic possibility and favors proactive movement of vulnerable bitcoin. Bryn Bennett, chief revenue officer at The Vault, stated that precise timing remains uncertain but custodians must prepare for an earlier arrival than expected. Bennett added that any decision to freeze coins should rest with Bitcoin network governance rather than external mandates.

Migration Challenges Beyond Active Wallets

Even if networks adopt quantum-resistant cryptography, coins held in lost, forgotten or inaccessible wallets present a separate difficulty. Owners who cannot or will not move funds leave those addresses exposed indefinitely. The problem extends beyond bitcoin to stablecoin systems, bridges and other infrastructure that rely on the same signature schemes.

The alliance intends to supply migration guidelines and common tests rather than prescribe solutions for any single network. Preparing an entire ecosystem for new cryptographic standards requires coordination among developers, miners, exchanges, wallet providers and users, a process that could take years once concrete proposals emerge.

For the moment the threat remains theoretical. Current quantum hardware lacks the scale and error correction needed to compromise bitcoin or other major networks. The Quantum Alliance’s formation signals an industry effort to define readiness criteria and practical upgrade paths while the window for preparation remains open.