Satoshi

NaoX Protocol

Bitcoin

Adam Back

<p>Paradigm Bitcoin general partner Dan Robinson published a proposal on May 1 for Provable Address-Control Timestamps, or PACTs, a system that lets dormant Bitcoin holders privately timestamp proof of key ownership before quantum computers arrive, creating a potential rescue path for Satoshi Nakamoto’s estimated 1.1 million BTC.</p>
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   <li>PACTs use three steps: a secret salt, a BIP-322 ownership proof, and an OpenTimestamps commitment anchored on-chain, all without any public on-chain transaction.</li>
   <li>If Bitcoin later implements a quantum sunset soft fork, PACT holders can submit a STARK zero-knowledge proof to reclaim coins while keeping their keys hidden.</li>
   <li>Robinson wrote that Satoshi revealing keys in any forced migration would mean having to “tell the world that they are alive and still in possession of their keys.”</li>
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<p>Robinson published PACTs on May 1, framing the design as a hedge against what he calls the Satoshi Problem inside Bitcoin’s quantum threat discussion. The official Paradigm <a href="https://www.paradigm.xyz/2026/05/pacts-protecting-your-bitcoin-from-a-quantum-sunset" rel="noopener noreferrer nofollow">post</a> outlined the dilemma: if quantum computers arrive before Bitcoin adapts, old addresses with exposed public keys face theft.</p>
<p>If Bitcoin rushes a sunset soft fork to freeze those addresses, dormant holders face a forced, public coin migration. PACTs offer a third path, letting holders timestamp proof of ownership silently in 2026 without doing anything further until a rescue mechanism is standardised.</p>
<p>As crypto.news <a href="https://crypto.news/is-bitcoin-quantum-safe/" rel="noopener noreferrer nofollow">reported</a>, approximately 1.7 million BTC remain in quantum-exposed address types, including Satoshi-linked wallets worth roughly $75 billion.</p>
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<p>The proposal builds on BIP-361, authored by Casa CSO Jameson Lopp, which defines a phased migration away from legacy signatures after which unmigrated coins would be frozen.</p>
<p>Bitcoin.com <a href="https://news.bitcoin.com/paradigm-researcher-proposes-pacts-to-shield-dormant-bitcoin-from-quantum-computing-risk/" rel="noopener noreferrer nofollow">noted</a> that Robinson acknowledged multisig, complex scripts, and hardware wallet support would all require further standardisation, and that Bitcoin may never implement a quantum sunset.</p>
<p>As crypto.news <a href="https://crypto.news/bitcoins-quantum-fight-pits-adam-back-against-coin-freeze-proposal/" rel="noopener noreferrer nofollow">documented</a>, Bitcoin’s quantum debate has been intensifying in 2026 after Blockstream CEO Adam Back argued at Paris Blockchain Week for optional, opt-in quantum-resistant upgrades rather than forced wallet freezes, directly challenging the BIP-361 approach PACTs are designed to complement.</p>
<p>As crypto.news <a href="https://crypto.news/we-asked-an-expert-about-quantum-computer-threat-as-google-and-blackrock-ring-the-alarm/" rel="noopener noreferrer nofollow">tracked</a>, Naoris Protocol CEO David Carvalho warned that dormant wallets including Satoshi’s would be “ripe for the picking” once quantum computers reach sufficient capability, and that a quantum hack on Bitcoin “would lead to a real loss of trust” in the asset.</p>
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Paradigm Bitcoin launches PACTs, a quantum proposal that could let Satoshi prove he is still alive

crypto.news

Other articles published on May 4, 2026

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