Bitcoin’s Quantum Risk Is Real but Not Immediate, Galaxy Says

Overview

• Galaxy Digital frames quantum computing as a credible long-term threat to Bitcoin’s signatures while stressing that the network has time to respond.
• Current vulnerability concentrates in coins with onchain public keys due to address reuse, older formats, or custodial practices, leaving most holdings not immediately exposed.
• Project Eleven estimates roughly 7 million bitcoin could be vulnerable under a long-exposure definition, though exposure estimates vary widely across analyses.
• Technical work includes Pay-to-Merkle-Root (BIP-360) to avoid always-visible public keys, plus research into post-quantum schemes like SPHINCS+ despite larger signature sizes.
• Additional proposals such as an hourglass spending limiter, commit-and-reveal protections, and zero-knowledge approaches reflect a layered defense, with an immediate 'Q-day' attack seen as unlikely given the small set of capable actors.