Paradigm partners release PACT proposals, Satoshi-era holders can prove control without moving BTC

BlockBeats News, May 2 — The concern over quantum computing in Bitcoin has always involved a “Satoshi-related dilemma.” If a sufficiently powerful quantum computer is developed, the 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 about $84 billion. Senior developer Jameson Lopp and five other developers officially proposed this plan in mid-April through BIP-361, which will gradually phase out addresses vulnerable to quantum attacks over a five-year timeline and freeze any coins that fail to migrate.

But this proposal creates another problem: Satoshi and all other long-dormant holders would have to “come forward” publicly, or risk losing access to their assets. Paradigm general partner Dan Robinson released a proposal on Friday, suggesting a way to avoid this trade-off, centered around the concept of “Proof of Address Control Timestamp” (PACTs).

The core idea of PACTs is not to move coins, but to add a timestamp to proof of ownership at a specific date, without revealing any information until the wallet owner actually needs to spend. If Bitcoin later implements a soft fork to freeze coins vulnerable to quantum attacks, this protocol could include a rescue path that accepts STARK proofs (a type of zero-knowledge proof that remains secure against quantum computers), demonstrating that the holder created their commitment before quantum hardware existed. When the holder wishes to spend, they submit this proof, and the network releases the corresponding coins. This redemption process reveals no information about the address, amount, or even the original timestamp creation time.