BIP 361 Would Freeze $420B in Bitcoin to Counter Quantum Threat

Published on April 14 by Jameson Lopp and a coalition of Bitcoin researchers, BIP 361 lays out a multi-year roadmap to replace Bitcoin's current ECDSA and Schnorr signature algorithms with quantum-resistant alternatives. The proposal identifies a growing vulnerability: over 34% of all bitcoin currently have an exposed public key on-chain, meaning a sufficiently powerful quantum computer could theoretically reverse-engineer private keys and drain those wallets.

The plan unfolds in three phases, all measured from a single activation point. Phase A, kicking in three years after activation, would block new deposits to legacy address types while still allowing spending from them. Phase B, at five years after activation, would invalidate all legacy signatures entirely, freezing any unmigrated funds. Phase C proposes a research-dependent rescue mechanism using zero-knowledge proofs that could allow frozen wallet holders to prove ownership and recover their coins.

The scale of potentially affected bitcoin is enormous. An estimated 5.6 million BTC, roughly 28% of total supply, sits in wallets that would be frozen under Phase B if their owners take no action. That total includes Satoshi Nakamoto's estimated 1.1 million BTC, which have never moved and lack any known entity to migrate them.

Critics argue the proposal amounts to a forced confiscation of dormant coins, effectively altering Bitcoin's core property-rights guarantees. Supporters counter that without proactive measures, quantum computers could steal those same coins outright, creating a far worse outcome for the network. The debate highlights a core tension in Bitcoin governance between individual sovereignty and network-wide security.

BIP 361 is in the early discussion phase and would require broad community consensus before any activation timeline begins. The proposal has its own informational site at bip361.org. Developers are actively soliciting feedback on the Phase C recovery mechanism, which remains the most technically uncertain component. No activation date has been set, and the full timeline from activation to the Phase B freeze would span five years, with an additional research phase beyond that.