> What I don't understand is where the signature came from -- I do see a Jan 2009 transaction involving that address on various blockchain explorers, but that particular signature is nowhere to be found. This could absolutely just be me not understanding how all of this works, but in order for this to be "really big news" I think you'd have to show proof that the signature given was posted with the transaction back in 2009. Otherwise, it just means that Hal Finney's wallet is compromised and someone has been signing random messages with it.