Six Bitcoin developers want to freeze every coin that doesn’t upgrade before quantum computers arrive.
BIP-361, a draft proposal introduced by Jameson Lopp (Casa CTO) and five co-authors, lays out a three-phase migration from ECDSA and Schnorr signatures to quantum-resistant alternatives. The kicker: unmigrated coins become permanently unspendable at the consensus level. Not locked. Not recoverable through some future mechanism. Frozen by the network itself.
The numbers are startling. Over 34% of all bitcoin in circulation (roughly 6.9 million BTC) have exposed public keys on-chain. These are theoretically vulnerable to Shor’s algorithm once quantum hardware reaches sufficient scale. Google’s quantum research team now estimates that could happen with approximately 500,000 physical qubits, 20x fewer than previously thought. Their projected timeline: somewhere between 2027 and 2030.
The three phases span roughly five years:
- Phase A (~3 years): Block new transactions from sending funds to legacy address types. Users can still move coins out of vulnerable addresses.
- Phase B (~2 years after Phase A): Network nodes reject all ECDSA/Schnorr signatures at the consensus level. Anything not migrated is frozen.
- Phase C (timeline uncertain): A limited recovery mechanism using zero-knowledge proofs tied to BIP-39 seed phrases. This part is still under research.
“Even if Bitcoin is not a primary initial target of a cryptographically relevant quantum computer, widespread knowledge that such a computer exists and is capable of breaking Bitcoin’s cryptography will damage faith in the network.”, BIP-361 authors
The elephant in the room is Satoshi Nakamoto’s estimated 1.1 million BTC (roughly $74 billion at current prices). Nobody has those keys. Under BIP-361, those coins would be frozen permanently, effectively removed from the supply. The proposal’s authors invoke Satoshi’s own logic: “Lost coins only make everyone else’s coins worth slightly more.”
Not everyone agrees this is the right approach. Blockstream CEO Adam Back is pushing for voluntary, optional quantum-resistant upgrades instead of a mandatory freeze. BitMEX Research proposed a “canary fund” as a middle ground: conditional freezes triggered only by demonstrated quantum capability.
Lopp himself describes BIP-361 as “a rough sketch” and says he doesn’t believe mandatory migration is necessary yet. That’s an unusual posture for a proposal author, and it signals this is a conversation starter, not a finished plan.
Why We’re Watching
This proposal forces a question Bitcoin has been avoiding for years: who actually owns dormant coins? Freezing 6.9 million BTC by consensus isn’t a technical upgrade. It’s a philosophical one. Bitcoin’s core promise is permissionless ownership. BIP-361 argues that promise has to bend when the cryptography underneath it breaks.
The urgency math doesn’t add up yet. If Google’s 2029 estimate is right and activation hasn’t happened, a five-year migration wouldn’t complete in time. That gap between “when we need to start” and “when we’ll agree to start” is the real vulnerability.
Watch NIST’s post-quantum signature adoption rate and Google’s qubit roadmap. If either accelerates, this conversation moves from theoretical to urgent overnight.