Developers Propose Freezing Legacy P2PK Bitcoin Wallets

Developers introduced BIP-361 in April 2026, a draft Bitcoin Improvement Proposal authored by Jameson Lopp and five contributors that would restrict legacy P2PK addresses to protect roughly 6.7 million BTC, including an estimated 1.1 million coins associated with early Bitcoin activity. The draft lays out a multi-year schedule to limit new inflows to exposed addresses, phase out legacy signature methods and provide a recovery path for locked funds.

P2PK addresses reveal public keys on the blockchain when they receive funds. Cryptographers say a sufficiently powerful quantum computer could use those public keys to derive the corresponding private keys and move funds without the original holders. The proposal targets addresses and signature schemes that already expose public key material on-chain.

BIP-361 sets three phases tied to activation. Phase A would begin three years after activation and forbid sending new BTC to old-style addresses while still allowing those addresses to spend existing balances. Phase B would begin five years after activation and invalidate legacy signature algorithms such as ECDSA and Schnorr. Phase C would create a recovery mechanism based on zero-knowledge proofs to allow owners to reclaim funds that remain locked after the earlier phases.

Authors estimate the draft covers about 34% of the total Bitcoin supply held in legacy formats. The proposal cites academic roadmaps that place a cryptographically relevant quantum computer in the 2027–2030 window and warns that an attacker could quietly derive private keys and drain funds before victims or watchers detect activity.

Supporters say a scheduled migration would give wallets, exchanges, custodians and miners private incentives to upgrade and would set clear deadlines for coordination. Hunter Beast, an engineer at MARA Protocol who contributed to related proposals, wrote that “quantum threats are not as far from reality as currently perceived,” and urged action on a shortened timeframe.

The plan has drawn criticism from some parts of the Bitcoin community. Critics described the measures as coercive and labeled the proposal confiscatory for its requirement to make legacy signatures unusable. Opponents questioned whether miners and node operators would enforce rules that leave on-chain balances effectively unspendable and warned of legal and reputational risks for firms that participate. TFTC founder Marty Bent characterized the approach as inconsistent with long-standing expectations about consent in the network.

Financial and institutional actors have begun to flag quantum computing as a material risk. Some analysts say recent market moves may reflect partial pricing of quantum risk, and major cryptocurrency firms and institutional investors have identified quantum computing as a potential industry concern in regulatory filings. BIP-361 remains a draft and would require broad community discussion and consensus before any activation. The proposal has prompted a debate over timelines, technical details and the balance between network security and user control.