Quantum computing's growing processing capabilities have prompted discussions within cryptocurrency circles about whether Bitcoin addresses — among them the long-dormant holdings attributed to Satoshi Nakamoto — might one day become vulnerable to decryption. Several of the industry's biggest names, Coinbase among them, have begun directing funding toward addressing what could be a vulnerability in the underlying security architecture.
The exchange platform provided additional detail in its latest disclosure. On Tuesday, Coinbase published a blog post detailing the specific protections it wants built into any plan to shield Bitcoin against quantum-computing threats. The firm outlined its position across seven points, calling for a transition approach that would shield both existing and newly formed funds, make efficient use of Bitcoin's constrained block space, allow full nodes to validate transactions independently within resource limits, function within institutional custody arrangements, remain accessible to standard wallets, and offer the broader ecosystem a credible path forward for coins that are unable or unwilling to move.
The architecture Coinbase is pushing for would keep the coin-storage layer and the signature mechanism as distinct components, allowing post-quantum cryptographic methods to be introduced or replaced without rebuilding the broader structure. The cryptocurrency exchange has indicated openness to a phased approach for any transition. One variant under consideration would allow the same pool of funds to be unlocked by either a conventional cryptographic key or a quantum-resistant alternative — a so-called 1-of-2 arrangement — alongside signing schemes built to work alongside multi-party computation (MPC), the private-key distribution method that Coinbase and a number of its institutional clients rely on to protect holdings from theft.
Among the items addressed are advance groundwork undertaken well before quantum hardware reaches the threshold of cryptographic relevance, the retention of a stateless signature mechanism as a fallback, implementation robustness, and a defined migration pathway for wallets that have not yet transitioned. Coinbase's published position holds that unresolved questions around dormant, previously exposed funds can be addressed on a separate track — with the company's post describing legacy assets as a distinct challenge for both governance and engineering, one that does not need to be resolved before other work advances.
Wallets relying on older address formats where the underlying public keys have never been concealed fall into this grouping, alongside other holdings from the network's earliest days — among them, the coins attributed to Satoshi. Cryptocurrency holdings tied to lost or inaccessible private keys form a pool of inactive assets that a sufficiently advanced quantum-decryption system could, in theory, unlock and redirect to whoever controls it.
Questions around whether bitcoin held in addresses exposed to quantum-computing vulnerabilities ought to be restricted have taken hold within the cryptocurrency community. BIP-361 — a draft technical specification that Jameson Lopp, co-founder and Chief Security Officer at Casa, contributed to developing — would bar outbound transfers to wallet addresses carrying exposure to quantum computing attacks, while also placing restrictions on future spending tied to those same addresses unless their holders go through a designated quantum-safe recovery procedure.
A document released in June by Coinbase's quantum advisory board examined the question of what ought to happen to holdings that remain in non-quantum-safe addresses, walking through the tradeoffs among outright freezing, leaving those assets untouched, and various intermediate positions — all without endorsing any particular path. Figures put forward by the board placed approximately 1.7 million bitcoin within the oldest address type flagged as exposed to risk, with the broader pool of potentially affected holdings reaching around 7 million bitcoin across all such categories.
Coinbase has expressed a preference, at this stage, for extending protections to users already prepared to make the transition. The post itself was framed by Coinbase as a contribution to open dialogue rather than any directive — language that stands apart from the company's posture during the block size dispute of 2015–2017, when Brian Armstrong, then as now the firm's chief executive, publicly backed alternative Bitcoin software clients designed to raise the network's block size cap through a hard fork.
Coinbase later put its name to the New York Agreement, which backed SegWit2x — a proposal that ultimately went unimplemented and drew pushback from critics who contended it would concentrate too much sway over Bitcoin's direction in the hands of corporate players. In a 2016 email, Armstrong indicated that Coinbase was collaborating with several development teams behind the scenes to support protocol scaling, expressing a preference that those efforts not be constrained by what he called "early idealists"; separately, the report noted that Coinbase holds custody over roughly 5% of all bitcoin in circulation, while the company has been building its own bitcoin reserves through a programme of weekly purchases.
Two design directions have entered the conversation around BIP-360 — the Pay-to-Merkle-Root output type at the heart of the proposal, alongside a community-floated alternative designated P2TRv2. An August demonstration by a StarkWare researcher — executing what appears to be the first quantum-resistant transaction to clear the Bitcoin mainnet — relied on a technique compatible with the network's existing consensus rules, though specialists note the approach functions more as a contingency mechanism than a comprehensive fix.
For the signature layer of its evaluation request, Coinbase has put forward a list that takes in ML-DSA, SLH-DSA, and FN-DSA alongside SHRINCS — a space-efficient, hash-based contender that Blockstream Research originally put forward, threading a stateful path together with a stateless fallback mechanism derived from SLH-DSA. The Bitcoin Security Consortium — a body drawing membership from BlackRock, Fidelity Digital Assets, and Strategy, among other institutions — attracted Coinbase as a participant, with the group having committed $15 million across a three-year window in July toward funding developers and researchers focused on strengthening Bitcoin's underlying security infrastructure. Post-quantum protections are an area where developers within the Bitcoin technical community are already putting in active work, according to the consortium's own characterisation.
Shifting Bitcoin's consensus rules and moving the broader ecosystem in new directions can take years to unfold, and Coinbase has pointed to that timeline as the reason it believes the groundwork should be laid without delay. In a post on X, Ethereum Foundation researcher Justin Drake put forward the view that AI-driven advances in mathematics could compromise ECDSA — the signature scheme underpinning bitcoin private-key security and the same protocol at the heart of quantum-computing concerns — ahead of any quantum machine managing to do so. In a scenario Drake described as a worst case, the transition from safety to exposure could unfold over months rather than a longer horizon, prompting an advisory to those holding funds to transfer them, without undue alarm, to addresses whose public keys have not previously been disclosed.
Objections came from Yehuda Lindell, Coinbase's head of cryptography, along with a number of other specialists in the field. Lindell contended that recent AI advances on longstanding mathematical challenges carry no bearing on whether the computational problems underpinning cryptographic security are genuinely intractable, characterising the suggestion as unfounded alarm given the total absence of demonstrated capability — and went on to note that a system's ability to establish proofs for previously resistant theorems offers no logical basis for concluding that problems conventionally treated as computationally hard are anything other than that.
