Quantum Migration Could Expose Whether Satoshi Still Controls His Bitcoin, Says Adam Back

Blockstream CEO Adam Back suggested at Paris Blockchain Week that a planned transition to quantum-resistant Bitcoin addresses could shed light on whether Satoshi Nakamoto still controls his coins ^[1].

Any holder wishing to protect funds stored in quantum-vulnerable addresses would need to transfer them to a new format. Coins that remain unmoved after that migration window closes could reasonably be considered lost, Back argued ^[1].

Estimates of Satoshi's holdings range from 500,000 to 1 million BTC, according to Back, while blockchain analytics firm Arkham puts the figure at approximately 1.09 million BTC — currently worth around $81.6 billion ^[1].

Despite the concern, Back downplayed the urgency of the quantum threat, stating that a computer powerful enough to break Bitcoin's cryptographic signatures is likely at least two decades away. He characterized current quantum machines as less capable than a basic calculator and noted that their energy demands grow significantly as they scale ^[1].

His comments follow a Bitcoin Improvement Proposal published Wednesday by Jameson Lopp and five co-authors, which seeks to restrict future movement of coins held in older, quantum-exposed address formats ^[1]. Blockstream Research also previously proposed a hash-based signature scheme as a potential quantum-safe alternative to Bitcoin's existing cryptographic standards ^[1].