New Proposal Offers Satoshi Nakamoto a Stealthy Way to Verify Control Over Bitcoin Without Transferring Funds

Concerns surrounding Bitcoin's vulnerability to quantum computing have long been intertwined with the enigma of Satoshi Nakamoto. Millions of bitcoins, including the approximately 1.1 million attributed to the cryptocurrency's pseudonymous creator, currently valued at around $84 billion, reside in outdated wallets with exposed public keys, rendering them susceptible to theft by powerful quantum computers. The obvious solution is a soft fork that would eventually disallow transactions from these legacy addresses, compelling holders to migrate to quantum-resistant formats before potential attackers can deduce their private keys. Prominent developer Jameson Lopp, along with five other developers, proposed this exact solution in mid-April via BIP-361, outlining a five-year timeline for phasing out quantum-vulnerable addresses and freezing coins that fail to migrate. However, this proposal presents a new dilemma: Satoshi and other dormant holders would need to publicly re-engage or risk losing access to their assets. Dan Robinson, a general partner at Paradigm, has introduced a proposal that bypasses this trade-off by utilizing Provable Address-Control Timestamps, or PACTs. The core concept involves generating proof of ownership at a specific date without publicly revealing any information until the wallet owners actually need to spend their coins. A holder creates a random salt and uses BIP-322 to produce a proof of ownership, which, along with the salt, is bundled into an on-chain commitment and timestamped via OpenTimestamps. These files remain private. If Bitcoin activates a soft fork that freezes quantum-vulnerable coins, the protocol could include a rescue path that accepts a STARK proof, demonstrating the holder created their commitment before the existence of quantum hardware. The holder submits this proof when they wish to spend, and the network releases the coins without revealing any details about the original address, amount, or timestamp. PACTs address a specific gap in BIP-361 by providing a rescue path for wallets derived through BIP-32, the deterministic key generation standard. However, this requires Bitcoin to adopt a STARK verification protocol, which would necessitate a separate soft fork with broad community consensus. The verification infrastructure currently does not exist in Bitcoin and would require substantial new developments. Ultimately, PACTs offer a way to make the BIP-361 debate less binary, providing a choice between protecting against quantum theft and respecting dormant property rights, but the question remains whether Satoshi will utilize this solution.