Bitcoin's post-quantum planning has gained a more concrete recovery path, but the proposal also highlights who would be left out.

CoinDesk reports that Project Eleven and Jim Posen, lead developer of the Binius proof system, built a zero-knowledge method aimed at the recovery phase described around BIP-361. The idea is not to prove ownership with an exposed Bitcoin signature. After a sufficiently powerful quantum computer could derive an elliptic-curve private key from a public key, that signature may no longer distinguish the original owner from an attacker.

Instead, the proposed proof relies on wallet derivation. A user would show, without revealing secret material, that they know the parent key or seed path that generated a specific Bitcoin address. BIP-361's own text describes this kind of rescue protocol for HD wallets, including BIP-32-style derivation, as a possible way to let authentic holders recover legacy funds after stricter post-quantum rules arrive.

The limitation is important. Early pay-to-public-key coins, including coins commonly attributed to Satoshi Nakamoto, predate modern HD wallet trees. They have no parent seed path to prove. CoinDesk notes that those outputs would not be recoverable through this mechanism.

BIP-361 remains a draft and depends on a future post-quantum output type. It would first restrict new sends to quantum-vulnerable scripts, then tighten legacy ECDSA and Schnorr spending after a public deadline. The recovery proof is therefore not a Bitcoin upgrade by itself. It is a candidate tool for one hard part of migration: separating missed upgrades from stolen keys after signatures stop being enough.