Key facts
- Project Eleven introduced a post-quantum proof designed to verify Bitcoin wallet ownership after quantum attacks.
- The technique allows users to prove ownership by demonstrating knowledge of the parent key, which quantum computers cannot reconstruct.
- This offers a fallback for users who miss future migrations to quantum-safe addresses.
- The implementation builds on 'signature lifting' research and uses the Binius zero-knowledge proof system.
- Bitcoin improvement proposal BIP-360, aimed at quantum resistance, is in formal review.
Project Eleven has introduced a new cryptographic technique aimed at securing Bitcoin ownership in a post-quantum computing era. The proposal, developed with Binius maintainer Jim Posen, addresses the concern that quantum computers could forge digital signatures, making it impossible to prove wallet ownership.
The core challenge, according to Project Eleven CEO Alex Pruden, is not preventing quantum attacks but verifying ownership once private keys can be derived from public keys. After "Q-Day"—the hypothetical moment quantum computers can break current cryptography—a valid signature would no longer reliably prove ownership, potentially allowing attackers to steal funds.
Project Eleven's proposed solution leverages a wallet's key derivation path. It enables users to prove they control the parent key from which a private key is generated, without revealing the parent key itself. Since quantum computers cannot reconstruct this parent key, it allows legitimate owners to distinguish themselves from attackers even if their private key is compromised.
This recovery mechanism is designed as a fallback for users who might miss a future migration to quantum-safe addresses. The development comes as the broader industry is accelerating efforts toward quantum resistance. Bitcoin developers have advanced BIP-360, a proposal for quantum-resistant upgrades, into the formal review process. BTQ Technologies has also released a working implementation on its Bitcoin Quantum testnet.
Coinbase's quantum advisory council has warned that millions of Bitcoin could be vulnerable if owners fail to migrate to quantum-safe addresses. The push for quantum preparedness has also received a boost from government action, with President Donald Trump signing executive orders to speed the federal government's transition to post-quantum cryptography.