Coinbase Calls for Flexible Designs as Bitcoin Prepares for the Post Quantum Era

Coinbase has shared its technical priorities for moving Bitcoin to post quantum security and is urging the community to start preparing now, since the process will be complex and could take several years. The exchange, which holds 5% of all bitcoin, says it is already readying its own systems. In its view, defending the network against quantum threats takes more than picking a quantum-resistant signature scheme.

The ideal approach should protect both exposed and newly created funds, fit within limited block space, keep full nodes able to validate independently, work with institutional custody, support ordinary wallets and offer a credible path for coins that cannot or will not move. Coinbase says preparation should begin well before any announcement of a cryptographically relevant quantum computer, because consensus changes and ecosystem migrations take time.

P2MR, Hybrid Schemes and Signature Options

Coinbase wants output designs that separate the container from the signature scheme, so new systems can be added or swapped without a full redesign. It points to P2MR (BIP-360) and P2TRv2 as examples. It also backs staged protection, where active wallets use post-quantum or hybrid setups before a final policy on legacy signatures is decided, such as a 1-of-2 design with one classical ECDSA or Schnorr path and one post-quantum path. Any stateful signature support, it says, should come with a stateless option, because poor state handling can lead to forgery. It also wants at least one viable option to work well with MPC, a key layer of defense for large custodians.

Abandoned Coins Debate

On abandoned or inaccessible coins, Coinbase says the questions are hard and deserve debate, but the talks can run alongside technical work on post-quantum signatures. It believes Bitcoin will remain the most trusted cryptocurrency in a post-quantum world.