Fidelity Digital says quantum-proofing Bitcoin is possible but challenging

Fidelity Digital Assets has published a research report titled 'Bitcoin's Path to Quantum Resistance,' concluding that making Bitcoin immune to quantum computing threats is technically feasible but socially and politically challenging. The report details how future Cryptographically Relevant Quantum Computers (CRQCs) running Shor's algorithm could potentially break Bitcoin's current ECDSA and Schnorr digital signature schemes, allowing attackers to derive private keys from public keys. While no such quantum computers exist today, the report examines post-quantum solutions, notably Blockstream's SHRINCS BIP proposal formalized in 2026. The primary technical tradeoff of quantum-resistant algorithms is significantly larger signature sizes, which consume more block space and lower transaction throughput per block. However, Fidelity highlights that the most significant obstacle is achieving social consensus across Bitcoin's decentralized ecosystem of developers, miners, and node operators to implement these changes via soft forks. To address long-term cryptographic challenges, institutional heavyweights including Fidelity Digital Assets, BlackRock, and Coinbase formed the Bitcoin Security Consortium in July 2026 to fund post-quantum security research.