Quantum Warning Raises Questions About Bitcoin’s Ownership Model

An unnamed Coinbase head of cryptography warned that quantum computing could weaken the link between signing authority and ownership of Bitcoin (BTC).

A person able to sign a transaction may not necessarily be the owner. Bitcoin’s protocol may no longer be able to guarantee proof of ownership if that distinction breaks down.

The warning challenges the principle that control of signing keys establishes ownership. It frames quantum computing as a possible test of that principle.

Coinbase has outlined post-quantum signature options for Bitcoin, including flexible designs for a transition that could take years, as part of its post-quantum Bitcoin plans.