Bitcoin developers have a solution to quantum computing threats. The harder question is whether the network can agree on one in time. The quantum computing threat to Bitcoin is not primarily a technical problem — it is a political one.
Those are the central arguments of a new commentary published by Guillaume Girard, a venture associate at UTXO Management, the Bitcoin-focused investment firm and subsidiary of Nakamoto Inc. In a piece titled “Bitcoin and the Quantum Threat: A Non-Technical Guide,” Girard argues that while a cryptographically relevant quantum computer (CRQC) does not yet exist and may never reach the threshold required to break Bitcoin’s encryption, the community must act now — because the governance process that governs any protocol change moves at the pace of a state legislature.
Bitcoin’s security rests on elliptic curve cryptography, which protects the private keys that control wallet access. A sufficiently powerful quantum computer running Shor’s algorithm could derive a private key from an exposed public key, enabling theft at scale. Google’s Quantum AI team published research in March indicating that a machine with fewer than 500,000 physical qubits — far below earlier estimates of 10 million — could potentially break this encryption, with Google’s own internal target for post-quantum readiness set at 2029. Approximately 1.7 million BTC currently sit in legacy Pay-to-Public-Key (P2PK) addresses where public keys are permanently exposed on-chain, making them the most vulnerable targets.
A quantum solution is on the table for Bitcoin
Bitcoin Improvement Proposal 360 (BIP-360), authored by developer Hunter Beast, introduces a new output type called Pay-to-Merkle-Root (P2MR) that removes public key exposure from standard transactions. The proposal has been merged into Bitcoin’s development repository and is under active review.
A companion proposal, BIP-361, authored by Jameson Lopp, maps a three-phase migration away from vulnerable signature schemes, though Phase B of that plan could freeze coins in wallets that fail to migrate within a five-year window.
A separate proposal called Hourglass would allow quantum attackers to move stolen coins only in limited batches — potentially one BTC per block — throttling the economic damage and transferring fee revenue to miners.
The harder problem involves coins that cannot migrate: lost wallets, inactive holders, and an estimated 1.1 million BTC attributed to Satoshi Nakamoto. Girard identifies two candidate solutions, each with serious drawbacks.
The first would burn coins in quantum-vulnerable addresses after a deadline — an effective fix that critics say sets a dangerous censorship precedent for a protocol built on neutrality. The second, Hourglass, accepts that theft will occur but restricts the flow of stolen coins to dampen the price impact and market disruption.
Neither option is clean, and both require the same thing: broad social consensus across users, miners, developers, and — for the first time — large institutional holders like BlackRock.
Institutions are already reacting
The debate has moved beyond developer mailing lists. Jefferies removed its entire 10% Bitcoin allocation from its pension model portfolio in January 2026, with global equity strategist Christopher Wood citing quantum risk as a potential long-term threat to Bitcoin’s cryptographic foundation.
Strategy’s Michael Saylor announced a Bitcoin Security Program to coordinate with the broader security community on quantum preparedness, framing the issue as an engineering challenge rather than an emergency. Citi’s cybersecurity team has put a multi-trillion-dollar price tag on the quantum threat to crypto broadly.
Girard’s conclusion is measured: the real contest is between the timeline for a CRQC capable of breaking Bitcoin and the timeline for the community to activate a soft fork. Based on current data, he believes Bitcoin is on track — but notes that if developer action is perceived as too slow by sovereign and institutional buyers, those stakeholders have both the motive and the financial weight to accelerate consensus outside existing structures.
The marginal buyer of Bitcoin is no longer retail; it is governments and asset managers who will not tolerate inaction. Most experts still consider a practical attack at least several years away, but as Girard puts it, the fog of war makes the timeline unclear — and in this battle, waiting for certainty is itself a risk.
Bitcoin Magazine is published by BTC Inc, a subsidiary of Nakamoto Inc. UTXO Management is also a subsidiary of Nakamoto Inc. (NASDAQ: NAKA)
