Summary: a private key associated with the very first non-coinbase transaction in Bitcoin appears to have signed a message making the claim in the title. For t

Summary: a private key associated with the very first non-coinbase transaction in Bitcoin appears to have signed a message making the claim in the title. For those downplaying the claim based on the source, this is irrelevant. The signature and the public key are all that are needed. The author is irrelevant to verification, although he probably has an interesting story to tell about how he came about this message and signature. The payment was locked to this address: 1Q2TWHE3GMdB6BZKafqwxXtWAWgFt5Jvm3 The first payment can be viewed here: https://www.blockchain.com/btc/tx/f4184fc596403b9d638783cf57adfe4c75c605f6356fbc91338530e9831e9e16 https://www.blockchain.com/btc/tx/f4184fc596403b9d638783cf57... You can see that this payment was included in block 170. The network produces ~144 blocks/day. So this transaction occurred almost at the launch of the network. Hal Finney has claimed, without proof AFAIK, that this payment was made by Satoshi to him: https://bitcointalk.org/index.php?topic=155054.0 https://bitcointalk.org/index.php?topic=155054.0 The implication is that a private key known by Finney signed the message claiming that Satoshi was Paul Le Roux. The latter was the subject of a piece speculating that he was Satsoshi: https://www.wired.com/story/was-bitcoin-created-by-this-international-drug-dealer-maybe/ https://www.wired.com/story/was-bitcoin-created-by-this-inte... This doesn't necessarily mean that Finney was involved. You can browse the transaction history associated with the address here: https://www.blockchain.com/btc/address/1Q2TWHE3GMdB6BZKafqwxXtWAWgFt5Jvm3 https://www.blockchain.com/btc/address/1Q2TWHE3GMdB6BZKafqwx... As you can see, a signed transaction was published as late as ~2018~ 2017. Finney died in 2014. So there are a few possibilities for what's going on, including: 1. Finney is not dead. 2. Finney's private key was leaked to someone who signed the message. 3. secp256k1 cryptography (the kind used for Bitcoin signatures) is now broken. 4. Finney signed the message sometime before he died. Given that few outside of Bitcoin know about Finney's legendary status, (3) seems unlikely because the attacker could have just signed with the private key for the genesis block. This leaves (1) and (2), and (4). I'm doubtful about (1). Finney suffered from a horrible, fatal disease and it was obvious in the interviews he gave. The most likely explanations are (2) and (4) IMO. The presence of the transactions signed after Finney's death is consistent with (2). When a Bitcoin payment is spent, the private key often has little monetary value (but a lot of privacy value). So the cryptographic material encoding it might be treated in ways allowing it to be used by others. Then again, it's possible that Finney signed the message, later died, and his private key was leaked. However, you slice it, this is not clear cut. There are various kinds of evidence that would make it more so, but AFAICT, they have not yet surfaced. Edit: Maybe Finney signed the 2017 transaction before he died and then it was later published. This kind of thing might be done for estate planning (although not a good idea). The transaction: https://www.blockchain.com/btc/tx/70ec308460a38f6de25f89c6ed84bf68160c27834f13d17d5a713602e3a4786b https://www.blockchain.com/btc/tx/70ec308460a38f6de25f89c6ed... spends three coins locked to the 1Q2 address and is dated 2017-09-05. However, one of the coins was only appeared in 2017. This raises the question of where that coin came from and whether it could have been minted before Finney's death.