Overview
- Paradigm researcher Dan Robinson outlined PACTs, a method for Provable Address‑Control Timestamps that lets Bitcoin holders show they control a vulnerable address without moving any coins.
- Under PACTs, a holder creates a secret salt and signs a standard message with BIP‑322, which proves control without spending, then anchors a hash of that package using OpenTimestamps, which batches many such commitments into one blockchain entry.
- The rescue path envisions that if Bitcoin later freezes old, public‑key‑exposed addresses through a soft fork, a spender would present a STARK proof showing their timestamped commitment existed before quantum‑capable machines, without revealing the address or balance.
- The proposal seeks to soften the hard choice posed by BIP‑361, which would phase out vulnerable address types and freeze unmigrated coins, and it adds a recovery route for BIP‑32 deterministic wallets that BIP‑361 alone does not cover.
- PACTs depend on new infrastructure that Bitcoin does not yet have, including on‑chain STARK verification via a separate soft fork and support across multisig, scripts, and hardware wallets, and they cannot help truly lost keys such as any holdings that no one can still sign for, a risk highlighted by long‑dormant troves like those attributed to Satoshi Nakamoto.