New Proposal Enables Bitcoin Holders to Prove Control Without Exposing Assets

Quantum computing has long posed a threat to Bitcoin, particularly for wallets with exposed public keys, including those attributed to the cryptocurrency's creator, Satoshi Nakamoto. A proposed soft fork, BIP-361, aims to address this issue by phasing out vulnerable addresses, but it presents a dilemma for dormant holders like Satoshi, who would need to publicly claim their assets to avoid losing them. In response, Dan Robinson of Paradigm has introduced the concept of Provable Address-Control Timestamps (PACTs), which enables holders to generate a private proof of ownership at a specific date without revealing any information publicly until they need to spend their assets. This is achieved by creating a cryptographic commitment using a random salt and BIP-322, then timestamping it through OpenTimestamps. If Bitcoin implements a soft fork that freezes vulnerable coins, holders can use a STARK proof to demonstrate that their commitment was made before the existence of quantum hardware, allowing them to spend their assets without revealing any sensitive information. While PACTs offer a potential solution for holders like Satoshi, they require the adoption of a STARK verification protocol, which would necessitate a separate soft fork and substantial infrastructure development. Ultimately, PACTs provide a way to mitigate the risks associated with quantum computing, but their effectiveness depends on the proactive participation of holders, including Satoshi, who must create a commitment to benefit from this protection.