Roughly 1 million BTC mined by Satoshi Nakamoto across 20,000 addresses may be especially exposed to a future quantum attack because the addresses reveal public keys directly. Bitcoin security researcher Justin Drake said this does not justify panic: funds held in hashed addresses remain protected from this specific exposure until they are spent, because spending reveals the public key. He advised users to send change to a fresh address and avoid rushing into post-quantum cryptography (security designed to resist quantum computers), which is still being developed and could contain bugs. Bitcoin developers are testing responses, including a quantum-resistant transaction sent to mainnet in August through MARA’s private SlipStream mempool and Quantum Safe Bitcoin, as well as BIP-361, a proposal to phase out vulnerable address types. Analyst James Check estimated the credible Satoshi-era target at 1.716 million BTC, below the 6.9 million BTC figure cited in broader discussions, and said a full sale would pressure the market without necessarily causing a catastrophic outcome.