Many are believed to belong to Bitcoin’s pseudonymous creator Satoshi Nakamoto and other owners who lost their keys, meaning they can never be moved to safety. Another 5 million or so have been uncovered through address reuse, according to Project11, a research group tracking the issue, although most of those are believed to be active holdings in exchange wallets.
Swapping in quantum-resistant signatures is the easy part, but the battle is for the coins no one moves. One camp argues for a hard deadline, after which the signature schemes Bitcoin uses today, ECDSA and Schnorr, will stop being accepted and any non-migrated coins will become unusable. By leaving them live, this site says, it hands a future attacker, potentially a sanctioned state like North Korea, a cache of bitcoin large enough to crash the price and destroy the network’s legitimacy.
The other camp calls confiscation a violation of the absolute property rights Bitcoin was built on, and warns that it sets a precedent for freezing coins under government pressure later.
Between them sit the several proposals CoinDesk has tracked over the past two months.
Hourglasses will put a cap on how many vulnerable coins can be used per block to prevent a supply flood. BIP-361, from developer Jameson Lopp and others, would let migrated holders prove ownership after the cutoff with a quantum-resistant proof that doesn’t reveal any key. PACTs, from Paradigm’s Dan Robinson, would let owners timestamp a private claim now and move funds later without disclosing anything today.
