Coinbase Council: Bitcoin Must Prep for Quantum Threats Now

A Coinbase-convened advisory council of leading cryptographers says Bitcoin should begin technical planning for post-quantum signatures now, while declining to take a position on whether the roughly 6.7 million bitcoin exposed to a future quantum attack should eventually be frozen. The panel includes Scott Aaronson of UT Austin, Dan Boneh of Stanford and Justin Drake of the Ethereum Foundation, and shared its report with CoinDesk this week.

The exposure is concentrated in early addresses. About 1.7 million BTC sit in roughly 20,000 pay-to-public-key addresses that publish the owner's public key directly on-chain, most assumed to belong to Satoshi Nakamoto and other holders who lost their keys. Another 5 million BTC are exposed through address reuse, according to Project 11, though most of those are thought to be active holdings inside exchange wallets. ECDSA and Schnorr, the signature schemes Bitcoin uses today, are not quantum-resistant.

Why it matters

The council's starting point is that quantum computers are not a threat to blockchains today, and nobody knows when they will be. The risk model is asymmetric: the engineering work to migrate to post-quantum signatures takes years, and a surprise arrival of a sufficiently powerful machine would expose every legacy address at once. The council says that migration work is independent of the abandoned-coins debate and should not wait for it to be resolved.

Market impact

The fight the council refuses to join is over the coins nobody moves. One camp argues for a hard deadline after which unmigrated coins become unspendable, on the grounds that leaving roughly 6.7 million BTC in reach of a future attacker — potentially a state actor like North Korea — would let a single party crash the price and taint Bitcoin's legitimacy. The other camp calls that confiscation and a violation of the absolute property rights the network was built on.