Paradigm researcher Dan Robinson published a proposal on May 1 that could let dormant bitcoin holders, including those believed to be Satoshi Nakamoto’s coins, silently prove address control before quantum computers can crack their keys. Paradigm Researcher Proposes PACTs to Shield Dormant Bitcoin From Quantum Computing Risk Key Takeaways: - Paradigm’s Dan Robinson proposed PACTs on May 1, 2026, offering bitcoin holders a free, private way to timestamp address control before quantum threats arrive. - Over 1.1 million BTC worth roughly $75 billion in Satoshi-linked wallets face exposure if cryptographically relevant quantum computers emerge. - PACTs require no Bitcoin fork today but need future STARK verification support and community consensus to activate a rescue path. Bitcoin Holders Gain Silent Escape Hatch as Paradigm Targets Quantum Vulnerability The proposal, titled Provable Address-Control Timestamps (PACTs), outlines a three-step method using existing Bitcoin tools to timestamp cryptographic proof of wallet ownership. No onchain transaction is required. No public signal is broadcast. The holder stores a secret salt, a BIP-322 message signature, and an OpenTimestamps proof file, then waits. Dan Robinson, a general partner and researcher at the crypto venture fund Paradigm, framed the proposal as a hedge against a specific dilemma facing Bitcoin. If cryptographically relevant quantum computers (CRQCs) arrive before the protocol adapts, addresses with exposed public keys become vulnerable to theft. If Bitcoin rushes a sunset soft fork to freeze those addresses, dormant holders face a forced, public coin migration. For wallets believed to belong to Satoshi Nakamoto, that migration would reveal whether the pseudonymous creator is alive, active, and still holding keys. Researchers estimate those wallets hold approximately 1.1 million BTC, worth more than $75 billion at current prices. PACTs offer a third path. A holder generates a 256-bit secret salt and uses BIP-322 full message signing to prove control