Paradigm Partners Propose PACTs, Allowing Satoshi Era Holders to Prove Control Without Moving BTC

On May 2, concerns about quantum computing in relation to Bitcoin have always posed a ‘Satoshi-related dilemma.’ If a sufficiently powerful quantum computer emerges, millions of Bitcoins stored in old wallets with exposed public keys could be at risk of theft, including approximately 1.1 million Bitcoins allegedly belonging to the anonymous creator Satoshi Nakamoto, currently valued at around $84 billion. Senior developer Jameson Lopp and five other developers formally proposed this plan through BIP-361 in mid-April, which aims to phase out addresses vulnerable to quantum attacks over a five-year timeline and freeze any coins that fail to complete the migration. However, this proposal creates another issue: Satoshi and all other long-dormant holders would have to publicly ‘reveal themselves,’ or risk losing access to their assets. On Friday, Paradigm partner Dan Robinson released a proposal offering a way to circumvent this trade-off, centered around the concept of ‘Proven Address Control Timestamps’ (PACTs). The core idea of PACTs is not to move coins, but to timestamp proof of ownership on a specific date, without disclosing any information externally until the wallet owner genuinely needs to spend. If Bitcoin later activates a soft fork to freeze coins vulnerable to quantum attacks, the protocol could include a rescue path accepting STARK proofs (a type of zero-knowledge proof that remains secure against quantum computers), demonstrating that the holder created their commitment before the existence of quantum hardware. When holders wish to spend, they submit this proof, and the network releases the corresponding coins. This redemption process does not reveal any information about the address, amount, or even the original timestamp creation time.