On February 22, 2024, during Day 14 of the COPA v. Craig Wright trial at the UK High Court, Mike Hearn testified. His written witness statement, dated November 10, 2023, had been submitted in advance with five exhibits (MCH-1 through MCH-5).
On his interactions with Satoshi Nakamoto:
“I worked on Bitcoin in the early days and as part of that I interacted with Satoshi Nakamoto, only ever by email, and we effectively worked together on the project for a brief period of time until he retreated from the project and told me he was done with it.”
Hearn stated that his communications with Satoshi spanned from April 12, 2009 to April 23, 2011. He had first discovered Bitcoin from a mailing list called rippleusers@googlegroups.com (unrelated to the later company Ripple), and contacted Satoshi because “there was a lot about Bitcoin that wasn’t clear from the White Paper or the user interface of the app or the website.”
On meeting Craig Wright — the dinner (July 9, 2016):
Hearn recounted being invited to dinner in London by Jon Matonis, who appeared convinced that Wright was Satoshi Nakamoto. The dinner took place at Wild Honey, 12 St George Street, London. Also present were Wright’s wife and Stefan Matthews from nChain.
“Dr Wright was claiming to be Satoshi so I tried at one or two points to ask him things that I had always wanted to know the answer to in relation to Bitcoin and the actual implementation and specifically, details that weren’t in the White Paper that only Satoshi would know. He failed all of my check questions.”
On Wright’s answers:
“Some of Dr Wright’s answers were in the general area, but garbled. I didn’t get the sense he knew what he was talking about. The clarity of thought present in the emails from Satoshi, the White Paper and the Bitcoin project as a whole was not present when talking to Dr Wright.”
Hearn described Wright’s responses as “only slightly better than Star Trek-style technobabble” and said:
“I was like, I don’t get the sense at all that this guy designed the thing (Bitcoin) otherwise he’d be able to give a much more clear discussion of them.”
On SIGHASH_SINGLE — a specific technical test:
Hearn asked Wright about SIGHASH_SINGLE, a signing mode Satoshi had implemented but whose intended purpose was unclear even to experienced developers.
“That was one of the answers where he struggled (I got the impression he didn’t really know), and then Stefan told him he couldn’t answer.”
On Stefan Matthews’ role:
“Stefan Matthews was a bit of an enigma, he didn’t talk very much except to shut up Craig when he started struggling, well my perception was to give him an excuse to stop talking when he was about to dig himself a hole.”
After the dinner:
“Jon was there and the others were not (I think they had left already by that point), and he asked along the lines of ‘I think this guy is Satoshi, I want to know what you think, what did you make of him’, and I responded along the lines of ‘I didn’t get the impression I was talking to Satoshi to be honest’. I don’t think we discussed it much further than that.”
Cross-examination:
During cross-examination, COPA’s attorney asked only one question: “Are you Satoshi Nakamoto?” Hearn laughed and denied the claim.
[The COPA v. Wright trial concluded on March 14, 2024, with Justice Mellor ruling definitively that Craig Wright is not Satoshi Nakamoto.]