- A new proposal called BIP-361 would freeze all Bitcoin in quantum-vulnerable addresses—including Satoshi Nakamoto’s estimated 1.1 million BTC—after a five-year migration window.
- The plan, co-authored by cypherpunk Jameson Lopp, targets the roughly 34% of Bitcoin’s supply sitting in legacy P2PK addresses with exposed public keys.
- Critics say freezing coins violates Bitcoin’s core promise of permissionless ownership, while developers frame it as a necessary defense against a 2029 quantum deadline.
Bitcoin just got its first expiration date on “not your keys, not your coins.” A group of researchers led by cypherpunk Jameson Lopp have proposed BIP-361, a three-phase plan to migrate the entire network to quantum-resistant addresses—or permanently freeze anything left behind.
The proposal, titled “Post Quantum Migration and Legacy Signature Sunset,” was posted to Bitcoin’s official BIP repository on Tuesday. It builds on BIP-360, which introduced a new quantum-proof output type called pay-to-Merkle-root (P2MR) back in February. While BIP-360 protects new coins going forward, BIP-361 is what happens to the old ones.
And there are a lot of old ones. Roughly 1.7 million BTC—about 34% of the supply—sits in early pay-to-public-key (P2PK) addresses where the public key is exposed on-chain. That includes Satoshi Nakamoto’s estimated 1.1 million BTC, untouched since 2010-11, along with coins from hundreds of other early miners and dormant wallets. At current prices, that’s over $120 billion in quantum-vulnerable Bitcoin.
How BIP-361’s Three-Phase Freeze Would Work
Phase A kicks in three years after activation and blocks any new Bitcoin from being sent to legacy address types. Everyone has to move to quantum-resistant addresses. Think of it as the warning shot.
Phase B is the hammer. Five years after activation, old-style signatures get invalidated entirely. Any Bitcoin still sitting in vulnerable addresses becomes frozen—technically still “owned,” but permanently unspendable. The coins don’t disappear. They just stop existing in any functional sense.
Phase C offers a potential rescue mechanism using zero-knowledge proofs, though the specifics are still being worked out. It’s the escape hatch for people who genuinely lost access to their keys but can prove ownership through some cryptographic back door.
Lopp was careful to frame BIP-361 as a rough draft, not an imminent change. “Rather, it’s a rough sketch of one way we could approach the issue of a looming circulating supply shock,” he told Cointelegraph. He expects the proposal to “continue to evolve over the years as more research and development is conducted.”
The Quantum Timeline Is Getting Shorter
The urgency isn’t hypothetical. A recently released Google report warned that breaking Bitcoin’s cryptography may require significantly less quantum firepower than previously estimated. Some observers have cited 2029 as the realistic deadline for when a quantum computer could crack ECDSA—the elliptic curve algorithm that secures every Bitcoin wallet.
The math is straightforward: Shor’s algorithm can derive a private key from an exposed public key. Newer address types like Taproot keep public keys hidden until a transaction is made, but P2PK addresses from 2009-2011 broadcast their public keys on-chain by design. Those are the sitting ducks.
The proposal has predictably split the community. Bitcoin maximalists who built their identity around “no one can touch your coins” now face a developer proposal that says, actually, we might have to. Critics argue that freezing coins—even with a generous migration window—sets a dangerous precedent. Today it’s quantum threats. Tomorrow it’s regulatory compliance.
Developers counter that the alternative is worse: quantum computers silently draining wallets across the network, with Satoshi’s stash as the ultimate honeypot. BIP-361 doesn’t confiscate anything. It gives holders five years to act, then makes a defensive decision for everyone who didn’t.
Whether this proposal ever reaches activation is another question entirely. Bitcoin’s governance model moves glacially, and BIP-361 touches the most sacred property rights in crypto. But the conversation has officially started—and Satoshi’s frozen wallet might be the price of keeping everyone else’s safe.
