Unmasking the Creator of Bitcoin

Summary

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The Daily: "Unmasking the Creator of Bitcoin"

Date: April 9, 2026
Host: Natalie Kitroeff
Guests: John Carreyrou, Adam Back

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Overview

This episode dives into the longstanding mystery of Bitcoin’s creator, Satoshi Nakamoto. Investigative journalist John Carreyrou presents the findings of his year-long hunt to unmask Satoshi, culminating in extensive evidence that points to Adam Back, an influential cryptographer and early member of the cypherpunk movement. The episode features a thorough breakdown of Carreyrou’s methods and evidence, a confrontation with Adam Back, and a rare interview with Back himself to respond directly to the allegations.

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Key Discussion Points & Insights

The Enigma of Satoshi Nakamoto

• The Stakes:

  • Bitcoin’s anonymous inventor, Satoshi Nakamoto, remains unidentified 17 years after launching a technology that transformed global finance ([00:32]–[02:53]).
  • The identity matters: Bitcoin is central to a $2.4 trillion industry with significant influence on markets, technology, and even new billionaires.

• Quote:

  "It's in the public interest to know who is behind this. Who is this person who has upended our financial landscape?"
  — John Carreyrou ([02:08])

The Genesis of the Investigation

• Carreyrou’s interest in the mystery is reignited in 2024 after an HBO documentary names Peter Todd as Satoshi—a claim he finds unconvincing but inspiring ([04:44]–[06:09]).

• A pivotal moment occurs when Carreyrou observes Adam Back’s "tell" during a filmed denial, citing his body language as highly suspect ([06:51]–[07:41]).

• Quote:

  "I've come across a lot of liars in my career and to me his behavior was a tell."
  — John Carreyrou ([07:33])

Building the Case: Literary & Technical Forensics

• Textual Analysis:

  • Carreyrou dives into Satoshi’s known writings and matches unusual word choices and expressions against communication styles of Bitcoin’s top suspects.
  • Adam Back stands out for using nearly all the same quirky expressions as Nakamoto ([09:04]–[10:22]).

• The Cypherpunk Connection:

  • Both Satoshi and Back were entrenched in the cypherpunk mailing list—a group of techno-anarchists/cryptographers obsessed with digital privacy and electronic cash ([11:00]–[12:47]).
  • Adam Back was a prolific, vocal cypherpunk with many parallels to Satoshi, including libertarian philosophy, anti-copyright stances, and deep concern over spam ([12:47]–[16:07]).

• Crucial Technical Links:

  • Back’s invention of HashCash (an anti-spam cryptographic puzzle) is repurposed by Satoshi as Bitcoin’s mining algorithm ([14:40]–[17:26]).
  • Notably, Back disappears from the mailing lists during the crucial period Satoshi is active—likened to a "Batman and Bruce Wayne" scenario ([17:39]–[18:28]).

• Quote:

  "It stretches credulity that this guy who's been talking about exactly this same thing when it gets unveiled is AWOL."
  — John Carreyrou ([18:28])

Forensic Linguistics & AI Analysis

• Writing Tics & Stylometry:

  • Carreyrou identifies unique writing quirks ("partial pre-image" with a hyphen, erratic hyphenation, confusing 'its/it’s', 'also' at sentence end) shared by Back and Satoshi ([21:14]–[23:32]).
  • Experts in stylometry confirm Adam Back as the closest match to Satoshi’s writing, but note Hal Finney is also a near-twin ([24:30]–[25:34]).

• Advanced AI Methods:

  • Carreyrou teams with Dylan Friedman to systematically analyze thousands of mailing list archives using AI.
  • Multiple filters (hyphenation errors, spelling quirks, British/American variants, two spaces after periods) ultimately reduce the suspect pool from thousands to one: Adam Back ([27:21]–[30:28]).

• Quote:

  "When we screened our remaining eight for those who did the same things that Satoshi did, we were down to just one person. Adam Back."
  — John Carreyrou ([30:28])

Confronting Adam Back

• The Showdown:

  • Carreyrou confronts Back at a Bitcoin conference in El Salvador after repeated email silence.
  • Back is cordial but repeatedly denies being Satoshi, though Carreyrou detects suspicious phrasing and emotional cues ([31:07]–[34:47]).

• Memorable Moment:

  "He said, 'I'm not Satoshi. That's my position.' ... that doesn't sound like a statement grounded in fact. It sounds like a rhetorical argument."
  — John Carreyrou ([34:31]–[34:47])

• The Tell:

  • During an interview, Back responds to a Satoshi quote as if it were his own, which Carreyrou interprets as an inadvertent confession ([35:47]–[36:32]).

• Quote:

  "For someone who's bad with words, I sure did a lot of yakking on these mailing lists, actually."
  — Adam Back ([36:05])

Motives for Secrecy

• Personal Risk & Financial Secrecy:

  • If Satoshi’s true identity is revealed, Back would become one of the world’s richest individuals (1.1 million bitcoins, worth $70–80 billion), and a likely target for crime ([37:59]–[39:06]).
  • Disclosure issues: Taking a Bitcoin company public (IPO) would require revealing this fortune, possibly crashing the market ([39:06]–[40:03]).

• Community Ethos:

  • Bitcoin’s decentralization ideology resists the notion of an identifiable founder—"We are all Satoshi" ([40:06]–[41:05]).

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On-Air Debate: Adam Back Responds

Segment Start: [44:04]

Natalie Kitroeff directly asks Adam Back if he is Satoshi Nakamoto. Back flatly denies it:

• Quote:

  "No, I'm not... All of the circumstantial evidence has been analyzed extensively by many researchers. What we're left with is speculative analysis."
  — Adam Back ([44:46])

• Back notes the selection bias in targeting prominent cypherpunks and argues that Satoshi could just as easily be someone without a public profile ([44:46]–[46:03]).

• He responds to the forensic and AI evidence by attributing similarities to shared technical language in the cryptography community rather than authorship ([48:08]–[48:44]).

• Denies being Satoshi repeatedly and suggests Bitcoin’s mythology benefits from the founder’s anonymity ([49:03]–[50:43]).

Community, Ethics, and Public's Right to Know

• Carreyrou asks whether anonymity is in the public interest, given Bitcoin’s global impact.

  • Back responds that the technology’s significance now outweighs the intentions or identity of its creator ([50:43]–[52:26]).
  • He admits a "cypherpunk mindset" and a preference for Bitcoin’s current decentralized state ([52:35]).

• The IPO disclosure issue is raised; Back notes the legal stakes of nondisclosure but maintains his denial ([52:50]–[53:39]).

• On public belief: Back refers to the "Messiah" or "Life of Brian" meme—people will believe what they want, regardless of repeated denials ([53:49]–[54:28]).

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Notable Quotes & Memorable Moments

• On the gravity of the secret:

  "If I'm right, that Adam Back is Satoshi ... that could easily make him a target of what's known in the industry as a wrench attack."
  — John Carreyrou ([38:17])

• On myth versus identity:

  "The myth and the backstory that there was this founder and he left ... is a fascinating mythology ... that's why we're having this conversation."
  — Adam Back ([50:43])

• On the limits of proof:

  "The only proof that we'll believe is when someone moves ... Satohi's coins or ... signs with a cryptographic key ... as long as they don't have that cryptographic proof, they're going to say it's not good enough."
  — John Carreyrou ([41:05])

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Timestamps of Key Segments

• [02:08] – Why Satoshi’s identity matters
• [06:51] – The "tell" in Adam Back’s body language
• [10:22] – First clues linking Back to Satoshi via language
• [14:40] – HashCash as blueprint for Bitcoin
• [17:39] – Adam Back’s conspicuous absence from mailing lists
• [21:14] – Forensic linguistics & unique "writing tics"
• [27:21] – AI-driven narrowing of suspects
• [30:28] – Filter funnel reduces candidates to just Adam Back
• [31:07] – Carreyrou confronts Back at conference
• [34:31] – "That’s my position"—odd phrasing in denial
• [35:47] – The telling slip: confusing Satoshi’s words as his own
• [37:59] – Motives for continued secrecy
• [44:04] – Adam Back’s denial and conversation with Carreyrou
• [49:50] – Discussion of the value of myth and anonymity
• [53:49] – Adam Back on public belief and legendary status

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Conclusion

"Unmasking the Creator of Bitcoin" offers a gripping, methodical account of investigative reporting at the intersection of cryptography, finance, and human mystery. John Carreyrou presents robust, multi-layered evidence—textual, statistical, behavioral—pointing to Adam Back as Satoshi Nakamoto. Adam Back’s defense is measured and consistent denial, focusing on the community’s values and systemic independence of Bitcoin. Ultimately, the pod leaves listeners to draw their own conclusions, highlighting the enduring allure and ambiguity of Satoshi’s true identity.

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Highly recommended for anyone fascinated by cryptocurrency, cyber-mysteries, or the limits of digital anonymity.

Transcript

[Narrator]

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[Natalie Kitroeff]

From the New York Times, I'm Natalie Kitroweff. This is the Daily. It's been one of the world's biggest mysteries and best kept secrets. Who is the inventor of bitcoin? This is a person who's been known only by an alias, Satoshi Nakamoto. And despite many attempts to unmask him, he's remained anonymous for 17 years, even as his creation spawned a whole system of cryptocurrency, revolutionized finance, and minted a powerful new class of billionaires, including Satoshi himself. Today we talk to our colleague John Carreyrou, who says he thinks he found Satoshi. And then we talk directly to that person. It's Thursday, April 9th. Hi, John. Welcome to the studio.

[John Carreyrou]

Thanks for having me.

[Natalie Kitroeff]

John, you've just finished this truly extraordinary investigation, and I am obsessed with it. I can't stop thinking about it. It is incredible.

[John Carreyrou]

Thank you.

[Natalie Kitroeff]

So I want to start with a really basic question. What percent convinced are you that you have identified Satoshi Nakamoto?

[John Carreyrou]

Somewhere between 99.5% and 100%.

[Natalie Kitroeff]

Okay, that's pretty good. So say why that matters. The inventor of bitcoin, known as Satoshi Nakamoto, has been unmasked after all these years.

[John Carreyrou]

Well, I think bitcoin, it's fair to say, is one of the greatest financial innovations of the past few decades. It's created this new currency. It's made the concept of a decentralized currency on the Internet that is available all over the world that can bypass governments and banks possible. It's spawned a $2.4 trillion industry. And I think it's in the public interest to know who is behind this. Who is this person who has upended our financial landscape? What was motivating him? What caused him to create this decentralized electronic currency? I want to know and just talk

[Natalie Kitroeff]

about Satoshi, the alias of the founder of bitcoin, and the long history of these efforts to identify who he is.

[John Carreyrou]

Satoshi Nakamoto appeared on the Internet in late 2008 when he announced his white paper, which is this nine page, academic like document that outlines how bitcoin works. He then stuck around for two and a half years under that pseudonym to improve upon the software and perfect it with a group of early adopters. And then suddenly In April of 2011, he disappeared.

[Sponsor/Advertisement Voice]

Who is Satoshi Nakamoto?

[John Carreyrou]

And shortly thereafter, efforts began to to figure out who he was. The so called founders of Chi Nakamoto, the Ben Bernanke of bitcoin, no one

[Sponsor/Advertisement Voice]

actually knows who that is. Whether it's a man or a woman or even a group of people.

[John Carreyrou]

People have spent, not just journalists, but academics, Internet sleuths have spent the past 17 years trying to unmask this guy.

[Adam Back]

We know that the real Satoshi Nakamoto

[John Carreyrou]

doesn't want to be found.

[Adam Back]

So if he is the real guy

[John Carreyrou]

and no one had succeeded,

[Natalie Kitroeff]

what made you decide to pick this up and spend a year plus on this?

[John Carreyrou]

I've been fascinated with this for a long time, for probably more than a decade. And then in early 2022, I decided to try my hand at solving the mystery. And I started researching a book about it for several months. Realized pretty quickly that I was out of my depth and gave up. And then two years later, in the fall 2024, something happened that reignited my interest.

[Natalie Kitroeff]

Which was?

[John Carreyrou]

Well, I was sitting in the car with my wife in traffic on the Long Island Expressway and I always play this jazz funk station in the car. And she got annoyed and tired of it and she turned on this podcast that we both like. Well, Casey, this week we are talking about one of the greatest mysteries of the last 20 years on the Internet, which happens to be a New York Times podcast. The popular tech show Hard for. Last week, we got a new potential. Satoshi Nakamoto. There's a new. And I was immediately riveted because the hosts were discussing a new HBO documentary that claim to have unmasked bitcoin's creator, Satoshi Nakamoto. We drove home. As soon as we got in, I logged into the HBO Max app and pressed Play and watched it. With bitcoin being woven into the fabric of the financial system affecting everyone, perhaps

[Adam Back]

the question of Satoshi's identity was more pressing than ever.

[John Carreyrou]

In the end, I wasn't convinced by the film's conclusion. They singled out a young Canadian software developer named Peter Todd. And I felt like their evidence was too thin to justify, you know, asserting that they had solved the mystery.

[Natalie Kitroeff]

Still worth watching?

[John Carreyrou]

Yeah, absolutely. It's an entertaining romp through the world of crypto. But what really caught my attention was a scene in the middle. It features Adam Back, this British cryptographer who is actually a pretty influential person in the bitcoin community. He's got this mini empire of bitcoin related companies and he's sitting on a bench in Riga, Latvia, next to the filmmaker whose name is Cullen Hoback. Do you think it'll ever be known who Satoshi is?

[Adam Back]

I don't think so, no. I mean, just because all of the people that have been been identified have various reasons, believable reasons, why it's probably not them.

[John Carreyrou]

And Cullen starts enumerating the big satoshi suspects. Nick Saba is on the list. Hel Finney, you're on the list. And when he gets to Adam Back's name, you see Adam Back get very tense. His eyes start darting all over the place. His left hand gets all fidgety. And he denies vociferously that he's Satoshi.

[Adam Back]

Well, I thought you might think I'm Satoshi and I don't want that to be on the record. Really?

[John Carreyrou]

I mean, you're on the list of suspects.

[Adam Back]

Yeah, yeah. But you know, I was interested for you personally to understand that. Really, really, I'm not, you know, and

[John Carreyrou]

I've come across a lot of liars in my career and to me his behavior was a tell.

[Natalie Kitroeff]

Just because of the body language.

[John Carreyrou]

The body language? Yeah, absolutely.

[Natalie Kitroeff]

So normally I might be very skeptical of someone just saying, look, I know how to spot a liar. But you, John, have a very good track record on this matter. And I think this is the moment at which we should talk about your reporting resume for the listening public. You famously broke the story about how Elizabeth Holmes, startup Theranos was faking these blood tests that led to a federal investigation and then later her trial and imprisonment. In any case, I assume that's what you mean when you say you have your fair share of experiences with liars.

[John Carreyrou]

It is. She's not the only liar I've come across in my career, but she was a pretty big one.

[Natalie Kitroeff]

Okay, so you have this hunch based on body language. What do you do with it? Where does your inquiry begin?

[John Carreyrou]

So the thing with Satoshi is that he was really good at, at hiding his footprints on the Internet. The upshot is that there's not really any way to track Satoshi. And that leaves you with just his writings, which are the nine page bitcoin white paper, his emails to a couple of Internet mailing lists, and which are his emails to early bitcoin adopters.

[Natalie Kitroeff]

These are the things that we know there is consensus he did write and create.

[John Carreyrou]

Yes, absolutely. There's no question that the real satoshi is behind these texts. So that gives you a little something to work with. And I started reading it, and it was difficult reading because I didn't know anything about cryptography, and I didn't know anything about computer science and coding.

[Natalie Kitroeff]

And how many pages are we talking here?

[John Carreyrou]

Oh, we're talking about many hundreds of pages.

[Adam Back]

Wow.

[John Carreyrou]

And then I got the idea, well, why don't I write down words and expressions that satoshi uses that jump out to me as unusual? And then I thought, well, you know, there's been, like, a list of about 10 or 12 people that's been talked about for years and comprised of the top satoshi candidates. Why don't I at least take the names from this list and see if any of these guys use these same phrases or words as satoshi? I figured that the best way to do that was to do an advanced Twitter search, because a lot of these top satoshi candidates have Twitter accounts.

[Natalie Kitroeff]

Okay.

[John Carreyrou]

Sure enough, one of them used almost every single word and expression that I had jotted down in my notebook, and I jotted down More than 100.

[Natalie Kitroeff]

And that person was Adam Back. Your guy.

[John Carreyrou]

Yep. I got a shot of adrenaline when I realized this. I felt like the hunch that I'd had watching the HBO film was, you know, at the very least, partially founded, and quickly reminded myself that this didn't really prove anything. But I felt like it was a lead. And I asked myself if there was something else I could compare satoshi's writings to. And there was. There are these emails from this group, the cypherpunks, that Adam Back happens to have belonged to in the 1990s.

[Natalie Kitroeff]

And what exactly are cypherpunks?

[John Carreyrou]

The cypherpunks were this group of techno anarchists that was formed in the early 90s who believed in using cryptography to ward off government surveillance and censorship. I would say they were libertarians on steroids. Some of their ideas were really, you know, at the limits of the law. And they sometimes met in person in the Bay area. But mostly they communicated through something called an Internet mailing list, which is essentially big group email in old typewriter font that you receive in your inbox if you subscribe to it and you reply all to when you want to participate in the discussion. And it's very likely that one of the members of this community eventually went on to take the alias of Satoshi Nakamoto.

[Natalie Kitroeff]

Hmm.

[John Carreyrou]

Now, why was he thought to be a member of this group. Well, there are several indications that satoshi was one of the cypherpunks. The most obvious one is that he created bitcoin. And the cypherpunks greatest obsession, arguably was the concept of electronic cash. Another reason is that satoshi unveiled bitcoin and his white paper outlining bitcoin on the cryptography list, which is an offshoot of the cypherpunks mailing list. And the cryptography list was a place that a lot of cypherpunks went to after the cypherpunks list kind of petered out.

[Natalie Kitroeff]

So we know there's good reason to think that satoshi was in this cypherpunk community. We also know that Adam Back, the guy you think is actually satoshi, is also in this community of the cypherpunks. But how many other members are there? Like, how big is this universe?

[John Carreyrou]

Well, in their heyday, there were about 2,000 subscribers to the cypherpunk's mailing list. And you have to somehow narrow that down. In this case, I had what I felt was a pretty good lead, Adam back. And it turned out that Adam back was among the most prolific and vocal cypherpunks. So he wrote a lot of posts on the list. It made for some interesting reading. And I quickly began to see a lot of parallels between what he wrote about and what satoshi wrote. There's several posts in 97 where Adam back comes out and says on the list in no uncertain terms that he's a libertarian and that he sees these crypto anarchist mission as bringing about a more libertarian government. And that reminded me of something, as satoshi had said soon after unveiling bitcoin, he had said something along the lines of it's very attractive to the libertarian viewpoint. That was the first parallel. There was the fact that Adam back was anti copyright and that he was very worried by several legal precedents. One of them was the fact that Napster, the file sharing service, had been shut down after it had been sued by the music industry. And after that happened, he sent a post to the list saying that he'd come to the conclusion that basically anyone developing a peer to peer software program had to release it anonymously, otherwise they'd get in trouble. And that struck me as potentially a reason why satoshi had remained anonymous in releasing bitcoin. Another parallel was that they both seemed to have this strange preoccupation with spam spam.

[Natalie Kitroeff]

Like spam mail?

[John Carreyrou]

Yeah, exactly. Like junk mail. Spam was something that loomed large in the life of Adam Back, because he, in 1997 invented something called HashCash to combat spam.

[Natalie Kitroeff]

Okay.

[John Carreyrou]

It was a statistical puzzle solving system whereby if your computer was the first to solve the puzzle, this mathematical puzzle, then you would get issued a permission to email. In other words, it was like paying for a postage stamp.

[Natalie Kitroeff]

Okay.

[John Carreyrou]

It only took a few seconds for your computer to solve the problem. It presented more of a problem for spammers who were sending hundreds of thousands of emails at once. That tripped up spammers and that was the point of Back's invention. And now I noticed that Adam Back and Satoshi both talked about spam all the time. Not only that, they discussed some of the very same spam related ideas.

[Natalie Kitroeff]

I see there are many parallels, some of them seemingly very significant between Adam Back and Satoshi. But I gotta say I'm still not totally convinced because it seems like this was generally the way all the cypherpunks were thinking.

[John Carreyrou]

No, I mean, some of these things, like the libertarian thing, you can apply generally to a lot of the cypherpunks. There weren't many cypherpunks as obsessed with spam as Adam Back. Right, but I take your point. These were more clues. They're not enough to prove that Satoshi is Adam Back. But I kept looking and reading the cypherbunks list and soon enough I came across these posts where Adam Back, over the course of two years, basically between 1997 and 1999, laid out in detail virtually every single aspect of bitcoin. So it was to create a decentralized currency using peer to peer software where the payer and the payee would be anonymous, just like they are in bitcoin. It would have a publicly viewable ledger. It would use hashcash as the way to mint the coins. And Satoshi had ended up borrowing hashcash and turning it into the method by which new bitcoins were minted.

[Natalie Kitroeff]

Oh, wow.

[John Carreyrou]

Yeah.

[Natalie Kitroeff]

What you're saying is that basically years before bitcoin was created, you see Adam Back laying out the fundamental principles, the elements that are core to it when it's eventually created.

[John Carreyrou]

Absolutely. And there was one other really interesting clue. As I poured over these archives, I noticed that Adam Back disappeared from the cryptography mailing list before Satoshi posted his white paper there. And then he stayed away while Satoshi was active. So it was like Batman and Bruce Wayne. Whenever Bruce Wayne disappeared, Batman appeared. The bitcoin white paper was basically the closest manifestation of the electronic cash vision Adam Back had laid out. On the cypherpunks list a decade before. And when it was unveiled, Adam Back was nowhere to be found. I mean, don't you think that he would have at least said something and commented about it?

[Natalie Kitroeff]

Right.

[John Carreyrou]

It stretches credulity that this guy who's been talking about exactly this same thing when it gets unveiled is awol. And then, though he reappeared on the list before Satoshi disappeared, he never addressed bitcoin, he never talked about it until Satoshi vanished. And I thought that was very significant, but I didn't think I was there yet. I mean, this is a case that's been unsolved for 17 years now. There have been a bunch of attempts to unmask this guy, and I felt like I needed to provide more definitive evidence that I had the right man. So I decided to keep digging, to provide something that was almost forensic.

[Natalie Kitroeff]

We'll be right back.

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[Natalie Kitroeff]

Okay, John, this is sounding more and more like a detective novel. What did it mean to get more forensic evidence in this case? How do you even do that?

[John Carreyrou]

It meant looking much more closely at the way these two people wrote, the way Satoshi wrote and the way Adam back wrote and As I did that, I began to notice similarities in words and expressions and phrases that they used. For instance, so there was this cryptographic term that I noticed in Satoshi's writing, partial pre image, which he wrote, putting a hyphen between pre and image. And I went back to the cypherpunks and the cryptography mailing list and determined that over all the years that those lists were live, only two people had ever used that term, Adam Back and Hal Finney, who was another really important member of the cypherpunk community. And actually, many people have thought over the years that he is Satoshi Nakamoto. But there was one difference in the way they used that term. Hal Finney did not hyphenate preimage, whereas Adam Bak did.

[Natalie Kitroeff]

But, John, how much should we really read into this? Like, who among us hasn't screwed up a hyphen here and there?

[John Carreyrou]

You know, except this is a term no one else used amid this community of thousands of cryptographers who were active bantering on these lists for more than a decade. No one else but these two guys used that term. And one of them spelled it exactly the same way Satoshi did. And by the way, that hyphen in partial preimage, it wasn't the only weird hyphen in Satoshi's corpus. I actually found that Satoshi was very bad at using hyphens. He was pathologically incapable of using hyphens correctly. You know who else was pathologically incapable of using hyphens correctly? Adam Back. And it wasn't just hyphens. Satoshi had a habit of confusing its and its. Yes.

[Natalie Kitroeff]

I mean, who among us? But yes.

[John Carreyrou]

And he sometimes put also at the end of sentences, Adam Back did the exact same thing. There turned out to be a lot of similarities.

[Natalie Kitroeff]

And how significant are those similarities? Like, did you ask someone? Did you try to get a sense of how likely it is that any of that could just be coincidence?

[John Carreyrou]

So if you find one instance of similarities, it's not necessarily something you can hang your hat on. It's not enough on its own. But if you find a bunch, then it becomes more significant. And I talked to a forensic expert at Hofstra who ended up telling me that what I had done, the way I'd homed in on certain words and phrases that satoshi uses, is exactly what he does when he's working on cases where he's trying to identify a writer.

[Natalie Kitroeff]

You have to be a real grammar expert to crack this case, it turns out.

[John Carreyrou]

Yeah, it turned out that grammar was a key part of this investigation. I also talked to an expert in this thing called stylometry.

[Natalie Kitroeff]

What's that?

[John Carreyrou]

That relies on basically the distance between function words and someone's prose. Function words or small words, like to and from and. But to basically establish a stylistic fingerprint. And there was a guy in Paris, a French expert named Florian Caffiero, and I asked him to analyze the satoshi corpus and compare it with some of the top suspects. Took about six weeks for him to get back to me. So the suspense was kind of mounting. And when he got back to me, finally, he texted me to say that the person who was the closest match to Satoshi's white paper was Adam Back. But he immediately added, back was barely ahead of another person in the pool of candidates, and that was Hal Finney. According to Florian, they were barely distinguishable. And as a result, he felt that his analysis was inconclusive.

[Natalie Kitroeff]

Yeah. How did that feel for you?

[John Carreyrou]

Well, it was definitely disappointing. I'd spent, you know, many months researching, reporting this story.

[Natalie Kitroeff]

Right.

[John Carreyrou]

And I had felt so close, and now solving the mystery seemed out of reach again. But I also felt by then like I had a pretty good idea of what the problem was. I knew for a fact that Adam Back knew about stylometry and knew how to defeat it, because he'd been writing back in the 90s about how to defeat writing analysis.

[Natalie Kitroeff]

So Adam Beck knew how to cover his tracks, you're saying.

[John Carreyrou]

Right. So that stylometry wouldn't catch him.

[Natalie Kitroeff]

Interesting.

[John Carreyrou]

And so with that in mind, I pivoted to a new approach. What I did is I wanted to find a more systematic way of analyzing satoshi's writing and comparing it to cypherpunk's writing. So I brought in a New York Times colleague named Dylan Friedman, who's a journalist and an engineer and who had experience with this sort of thing. He knows how to use AI programs and machine learning. And Dylan and I, as a team, began collecting the archives of these cryptography mailing lists. We merged them into one big database and made it searchable so that we could then compare Satoshi's corpus of writings with it.

[Natalie Kitroeff]

So you're basically taking the kinds of analyses that you'd been doing by hand and trying to feed them all into one machine at once to see if the associations that you'd been noticing and picking up on actually did add up to one conclusive result.

[John Carreyrou]

That's right. I wanted to establish that no one else but Adam Back was doing these same Things in his writing that satoshi was doing. So we conducted three analyses, and one of the analyses, we compiled all the words that don't have synonyms that satoshi uses. And synonym less words tend to be technical words, so that would weed out common words that people use. And then we ran those words against our database and found that Adam back, among these thousands of other cryptographers, was the one who used those satoshi words the most. So that was one. Then we drilled down on hyphenation, and with the aid of an AI program, we determined that Satoshi had made more than 300 grammatical hyphenation errors. And we found that adam back had the most matches for these hyphenation errors. He matched 67 of those separate hyphenation errors. He was by far an outlier.

[Natalie Kitroeff]

Okay, so the evidence is mounting.

[John Carreyrou]

Yeah. And then we ran an analysis of these writing ticks that I had picked up on in satoshi's prose. And basically, we applied a filter for each of these satoshi writing tics to see how many cypherpunks displayed that writing tick, so to speak. The first one was we looked for the people who sometimes put two spaces between sentences like Satoshi did. And that eliminated 58 people and left us with 562 suspects. Then we screened for posters who use british spellings. That narrowed our pool to 434. Then we screened for posters who sometimes confused its and its or vice versa. That narrowed our pool to 114.

[Natalie Kitroeff]

Okay, getting closer.

[John Carreyrou]

Yep. Then we screened for those who sometimes finished sentences with also. That further shrank the field to 56. Then we we used another series of satoshi ticks. That brought us down to eight suspects.

[Natalie Kitroeff]

Wow.

[John Carreyrou]

And then we did one last round of filtering, which was that satoshi alternated between email without a hyphen and email with a hyphen between electronic cash spelled out and e cash abbreviated and hyphenated between the American Czech c h, e c k and the British Czech c h e q u e. And satoshi also alternated between the british and american forms of the word optimize. He used a z sometimes and an s other times. When we screened our remaining eight for those who did the same things that satoshi did, we were down to just one person. Adam back.

[Natalie Kitroeff]

Okay. Wow. I feel much more sold at this point. How are you feeling at this moment when you see that when there's just one who makes it through the gauntlet?

[John Carreyrou]

All those filters, I mean, that felt like pretty strong evidence to me. Not necessarily just on Its own. But combined with everything else that I'd found, all the other clues and pieces of evidence that I'd accumulated over the course of a year, I felt like, you know, this was kind of the icing on the cake.

[Natalie Kitroeff]

Okay, so you have your body of evidence. You feel pretty good about it. What's the move?

[John Carreyrou]

So at that point, I felt like I was ready to confront Adam back. The problem was, he wouldn't respond to me. I sent him several emails, and it was radio silence.

[Natalie Kitroeff]

Hmm.

[John Carreyrou]

And so I figured the better way to go about this was to try and intercept him at one of these bitcoin conferences that he's always attending throughout the year. And I noticed that the next one that was coming up was going to be in late January in El Salvador. So I packed my bags, and I flew to San Salvador at the end of January.

[Natalie Kitroeff]

And, I mean, what did you do when you got there? You just went around looking for a bag to tell them, hey, by the way, I've compiled a whole body of evidence that suggests that you are, in fact, Satoshi Nakamoto.

[John Carreyrou]

Yeah, that's basically what I did. I mean, I figured, well, maybe I can find him in the speaker's lounge. So I went over to the speaker's lounge, couldn't get in, and I posted myself not far away and just watched the door like a hawk, hoping that Adam back would come out of there and that I could accost him.

[Natalie Kitroeff]

This is a stakeout, Basically.

[John Carreyrou]

Yes. So my stakeout lasted about 30 minutes, and then, sure enough, Adam back came out with two colleagues, And I went up to him, tapped him on the back. He turned around, and he was a little flustered. He knew who I was. But he was cordial. And to my surprise, he agreed to meet me for an interview. Let me just. I want to call up something to use to show you my research. And I began laying out, piece by piece, my evidence. At one point, I pressed him hard on the fact that there was no trace of him for three years on the cryptography list, and that that coincided exactly with when satoshi was active. And so that's what seems so fishy to me. Someone like you, who outlined most aspects of Bitcoin 10 years before Bitcoin was created, who almost systematically chimed in when there were ecash discussions on both lists. When this white paper, which basically makes your vision happen, gets announced on the list, you're awol.

[Adam Back]

Ultimately, it doesn't prove anything. And I reassure you, it's really not me, but.

[John Carreyrou]

And as I started unspooling My evidence, his face began to redden and he got pretty agitated and defensive. And he said something like, well, that doesn't prove anything. We did a hyphenation analysis and you came out as the top match. You had 67 exact matches to Satoshi, hyphenation errors, and you were a huge outlier. The next guy had 38.

[Adam Back]

It's not me. But you know, I take what you're saying. This is what the AI said with the data, but it's still not me. So.

[John Carreyrou]

So he denied being Satoshi something like a half dozen times or more during the interview. But one of the denials was phrased in what I thought was a very interesting way.

[Adam Back]

Well, I have to say, I mean, because clearly I'm not Stoshi. Like, that's my position. And it's true as well. I mean, for what it's worth.

[John Carreyrou]

But he said, I'm not satoshi. That's my position.

[Natalie Kitroeff]

That's my position.

[John Carreyrou]

Yes.

[Natalie Kitroeff]

What interesting phrasing.

[John Carreyrou]

And I thought to myself, yeah, well that doesn't sound like a statement grounded in fact. It sounds like a rhetorical argument.

[Natalie Kitroeff]

Right.

[John Carreyrou]

But then he quickly caught himself and said something like, and it happens to be true, by the way.

[Natalie Kitroeff]

Wow.

[John Carreyrou]

If there's anything that I haven't brought up, I will definitely send it to you by email. Send it to Adam by. So the meeting ended on a cordial note. We shook hands like two chess players who had just had a hard fought match. And as I watched him walk away, there was something that nagged at me because toward the end of the interview, we had spent two hours together in his hotel room conversing.

[Adam Back]

And.

[John Carreyrou]

And toward the end of that two hours, he had said something that I felt certain had implied that he was Satoshi. And in the moment, I remember feeling a little jolt and looking up at him. But I couldn't remember when it was in the interview. It wasn't until a few days later when I was back in New York listening to the interview again, that I found that moment.

[Natalie Kitroeff]

And what was it?

[John Carreyrou]

So I was bringing up things that Satoshi had written that were similar to things that back had written. And I bring up this Satoshi quote. There's a quote that I mentioned earlier where Satoshi says, I'm better with code than with words.

[Adam Back]

I did a lot of talking though, for somebody. I'm not saying I'm good with words, but I sure did a lot of yakking on these lists, actually.

[John Carreyrou]

But before I had a chance to explain why I was bringing it up, he interrupted Me. And he said, well, something like, for someone who's bad with words, I sure did a lot of yakking on these mailing lists. And to me, it sounded like he was saying, I wrote that quote.

[Natalie Kitroeff]

Right. He just follows up on the satoshi quote and talks about himself.

[John Carreyrou]

Exactly. I had made crystal clear that I was quoting satoshi. I said, this is a satoshi quote. And then I read the satoshi quote, and before I could explain why I was bringing it up, he interjects. So I felt like he had slipped. I felt like the mask had fallen for a few seconds and he had become satoshi.

[Natalie Kitroeff]

I mean, that sounds like a slip up, right? It's hard to imagine feeling any other way about it.

[John Carreyrou]

Well, not according to him, because, of course, I emailed him about it, and he emailed me back saying, no, it wasn't a slip. I was just responding to the general observation that people often make that technical people are sometimes better with code than with words. And my reaction to that explanation was what? I didn't. I wasn't talking about a general observation. I was talking about a satoshi quote. And I suspect that Back knew that and that he was BSing me.

[Natalie Kitroeff]

Okay. In all this, what seems crystal clear is that Back is committed to denying that he's satoshi. He's committing to pushing back on your story. So if he is, in fact satoshi, why, John, is he so bent on keeping that a secret?

[John Carreyrou]

Well, that's a great question. I'd say the biggest reason by far is the fact that Satoshi mined 1.1 million bitcoins in bitcoin's early days. That's a fortune that, at today's prices, is worth somewhere between 70 and 80 billion dollars.

[Adam Back]

Whoa.

[John Carreyrou]

It would make him one of the richest people in the world. If I'm right, that Adam Back is satoshi, and if people know he's that rich and know that he holds that fortune in crypto as opposed to in a bank account, then that could easily make him a target of what's known in the industry as a wrench attack. These attacks are when people kidnap people who have a lot of crypto and extort them. And there have been many in the past two years in Europe and the U.S. and so there's real reason for him to fear that.

[Natalie Kitroeff]

And the reason that people who have their wealth in crypto are targeted for these kinds of attacks is because they alone hold the keys to these accounts, unlike someone who has their wealth in all sorts of traditional vehicles.

[John Carreyrou]

Right. If you're satoshi, Nakamoto, you just have a bunch of cryptographic keys that hold the keys to your fortune. And anyone who kidnaps you can try to extort those keys out of you. And there's another reason he wouldn't want to be unmasked, which is that right now, he's in the process of taking one of his bitcoin companies public on the NASDAQ stock market. Now, under U.S. securities law, when you are the CEO of a public company, you must disclose all material information to your investors. If Adam Back is satoshi and he's sitting on 1.1 million bitcoins, then that could be considered material information, because it means that he's sitting on a huge trove of bitcoins that, if it were suddenly sold, could crash the bitcoin market.

[Natalie Kitroeff]

Right. It's a lot of undisclosed wealth.

[John Carreyrou]

Absolutely. There's also one more very fundamental reason why Back wouldn't want to be unmasked as Satoshi, which is the ethos of bitcoin. It's this decentralized currency outside the control of governments. It's this collective software project that hundreds of developers have been working on for more than a decade. Bitcoin belongs to every member of the community. The community doesn't want a leader. It doesn't want an authority figure. In fact, one of the favorite slogans of the community is we are all satoshi.

[Natalie Kitroeff]

So just thinking about that ethos, that idea that the community has a vested interest in understanding themselves as the collective creators of this cryptocurrency, do you think that community is going to believe you?

[John Carreyrou]

I think there's going to be a faction of the community that will not believe me, and that will say, the only thing we'll believe, the only proof that we'll believe is when someone moves one or several or many of satoshi's coins or when someone signs with a cryptographic key associated with one of the wallets that holds these coins, as long as they don't have that cryptographic proof, they're going to say it's not good enough. There was an interesting moment in our interview in El Salvador where he said that what he thought would happen is that the coins wouldn't move until Satoshi died and left him to his heirs. Whoa. And that then the coins would be sold and that that would be when the mystery would be solved. And when he said that, it made me think, so that's what you're planning.

[Natalie Kitroeff]

Once John's story published, Adam Back's team reached out and asked if he could come on the Daily to respond, so after the break. Adam back.

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[John Carreyrou]

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[Natalie Kitroeff]

Adam Back welcome to the Daily. Thank you so much for coming on the show.

[Adam Back]

Of course. Thanks for having me on.

[Natalie Kitroeff]

So should I call you Adam or Mr. Back or.

[Adam Back]

Adam is fine.

[Natalie Kitroeff]

Mr. Nakamoto it is what everybody's wondering. You are here, of course, because my colleague at the Times, John Carrey Roo, just published an investigation in which he presents a giant body of evidence gathered over more than a year that points to you being the inventor of Bitcoin, someone who has operated under the alias Satoshi Nakamoto for 17 years. So I'm just gonna ask you point blank, are you Satoshi Nakamoto?

[Adam Back]

No, I'm not. I think, of course it's a fascinating topic as to who this person would be. And all of the circumstantial evidence has been analyzed extensively by many researchers. So effectively, I think what we're left with is sort of speculative analysis. And of course, looking at the historic writings, which John does an interesting job of in the article. I mean, I think there is some sort of inherent selection bias, if you like, in the sense that in looking at who might be Stochi, they're going to look for people with overlapping interests. And I'm probably as reasonable a candidate as any of the other top 20 that let's say people have looked at. But we don't have a reason to suppose that Satoshi would be participating at conferences, participating in documentary films, taking interviews and that kind of thing. And from that point of view, it seems more plausible that Sochi is one of the many clever people who've worked on Internet technology but don't have really a public profile, for example.

[Natalie Kitroeff]

So I think I want to bring John into the conversation. Hi, John.

[John Carreyrou]

Hi. Can you hear me, Adam?

[Adam Back]

Yep, loud and clear.

[John Carreyrou]

Adam, I just want to set aside for a second the question of whether you're satoshi, and ask you if Satoshi were calling into this show today, and I asked him, are you Satoshi, do you think he would say yes?

[Adam Back]

It's kind of hypothetical to me. Right. Because I'm not. But I have seen a number of people in interview settings being asked that question and saying they wouldn't say or something like that. Right? Yeah, I think that's the common answer, and it sounds logical to me.

[John Carreyrou]

In other words, the common answer would be that Satoshi calling into the show wouldn't admit that he's Satoshi.

[Adam Back]

Well, I mean, I think my assumption is Satoshi simply would decline to participate or, you know, be hard to identify, even as a candidate to try to contact or bring into an interview.

[Natalie Kitroeff]

So I just want to get to some of the specific pieces of evidence in John's story that I found most convincing. Just as a lay reader here, one of the things that really struck me was this very systematic analysis that John and our colleague Dylan Friedman, who works with AI and machine learning, did. They combed through thousands of pages of these forum posts and looked at specific kinds of grammatical errors, specific writing ticks, not just one, but a bunch of things. And they used three separate methods of analysis. And all three came to the same conclusion, which is that you were the number one match out of all of these people in this community to the writings of Satoshi.

[John Carreyrou]

Right. And we've gotten actually feedback. Dylan and I have gotten feedback today from readers. Some readers find the hyphenation analysis the most compelling and by far the closest match to these hyphenation error patterns was you.

[Natalie Kitroeff]

What do you make of that, Adam?

[Adam Back]

I mean, I guess it's coincidence, unless there is some kind of link in the sense that he did read my paper. Some of the things we're talking about hyphenating are sort of niche technical terms like proof of work. And so there. There are probably likely to be similarities, because for somebody to be, you know, fluent in cryptography and the technology, they would have read certain things, learned certain programming languages or Ideas and so have some common technical language, let's say.

[Natalie Kitroeff]

I mean, you're basically saying that this is coincidence, but I have to say it does feel as though what John has done goes much further than that. I mean, it is really robust, the level of, again, multiple analyses that he presents in the story.

[Adam Back]

Yeah. I mean, I can only tell you that it's not me. People who know me are pretty convinced that's the case.

[Natalie Kitroeff]

Okay, I just want to kind of finish this part of the conversation by just saying, John. I'm gathering that nothing he has said has changed your mind?

[Adam Back]

No.

[Natalie Kitroeff]

Okay. Well, it seems like we're gonna just have to agree to disagree. Adam, can I get you to address something that you said today on X in response to John's article coming out, which is that, and I'm quoting you here, I also don't know who Satoshi is, and I think it's good for Bitcoin that this is the case in the broadest state sense. Why do you think it's good that the founder of bitcoin remain anonymous?

[Adam Back]

Yeah, so I think it's more about the perception of bitcoin.

[Natalie Kitroeff]

What do you mean by that?

[Adam Back]

Well, there's bitcoin as a digital commodity, as a discovery rather than invention and systems that have a vocal founder. Then it gets viewed as more a company's product or a project. Whereas bitcoin is actually very chaotic and decentralized. You know, there are hundreds of individual developers, thousands of companies, different service providers, any one of which or dozens of which, could leave and rejoin and it wouldn't have much bearing on bitcoin. So from the point of view of both bitcoin being seen as a neutral digital commodity and it being viewed as a discovery rather than a company with

[Natalie Kitroeff]

a CEO, that's a virtue in your mind?

[Adam Back]

Yeah, I think that is actually beneficial. And of course, the myth and the backstory that there was this founder and he left in 2011 or 2012 is also a fascinating mythology behind bitcoin, and that's why we're having this conversation. Right, so I do understand, Adam, what

[John Carreyrou]

about the public's interest in knowing who Satoshi is so that they know what his motivations were? Isn't that a legitimate public interest, given how big a deal bitcoin has become, how many things it's altered in our modern world? You know, this person invented something that we have to reckon with every day, whether we like it or not. Isn't there a public interest there in knowing what the motivations were for creating this?

[Adam Back]

I mean, I think not necessarily in the sense that once the technology exists, it takes on an inertia of its own. Satoshi had one thing in mind, but ultimately, if humanity is using bitcoin, the people who use it, the economic actors, decide why it's valuable to them. So I think at this point the ideas of the person who put it together and implemented it are sort of secondary. Right. It's now a market phenomena. And you know, you could say that about the Internet too. Right. You know, there were some early pioneers behind email protocols and TCP IP and that came out of a particular use case in probably military applications initially. But that's not what the Internet's about today. It's like a general fabric for huge amounts of society, companies and individuals and conversations like what happened right now.

[John Carreyrou]

You're saying it's okay for Satoshi to wipe his hands of the consequences of his invention. And the consequences have not all been positive.

[Adam Back]

I mean, I think that I rather like the consequences of bitcoin, but you know, I have a kind of cypherpink mindset, kind of an archa capitalist, very free market viewpoint.

[Natalie Kitroeff]

You know, we should say now that if you are satoshi, it is in your personal interest also to conceal that you're about to take a company public. And that requires you to do all of these disclosures to the sec. If the SEC were to find out that you had hid the fact that you have 70 plus billion dollars in Bitcoin, which Satoshi has, I mean, that would be a big problem for you, right?

[Adam Back]

Hadn't really thought about that. But I mean, that could be another piece of evidence. Looking at the filings and seeing that there's no such disclos that.

[Natalie Kitroeff]

Well, I mean, you have to make the disclosure in order for it to be in there.

[Adam Back]

Right, But I mean, hiding a disclosure is not good. Right. The SEC filings are legal documents that are carefully reviewed by securities lawyers and so on. Right.

[Natalie Kitroeff]

Okay. Can I ask, Adam, do you think the public will believe you when you say that you are not Satoshi

[Adam Back]

People sometimes. I mean, there's a lot of memes on the Internet and the bitcoiners love their memes. And one of the memes is a Monty Python sketch where the crowd decides this fellow is a religious figurehead and he denies it. And every denial they just say, oh, you know, that person would deny it and there's no shaking their conviction. So at some point, you know, you can say the truth, you can explain why or not, but people are going to draw their own conclusions.

[Natalie Kitroeff]

Well, Adam John, thank you both so much for being here.

[John Carreyrou]

Thank you for having me and thank you Adam for coming on the show and speaking to us at such length.

[Adam Back]

Yeah, thank you Paz.

[Natalie Kitroeff]

Here's what else you need to know. Today, a new wave of attacks tested the US And Iran's day old ceasefire, which was strained by confusion over the deal's traffic terms and over the status of the Strait of Hormuz. One of the biggest points of contention was whether the truce applied to Lebanon. The Israeli military said it carried out some of its largest strikes in Lebanon yet killing more than 180 people there. President Trump and Israeli Prime Minister Benjamin Netanyahu said the ceasefire did not include Lebanon, but Iran and Pakistan, which home mediate the truce said it did. On Wednesday afternoon, Iran said the Strait of Hormuz, which Trump demanded be kept open as part of the ceasefire deal, had been fully closed and that some tankers had been turned away. Today's episode was produced by Stella Tan, Jack Desadoro and Nina Feldman. It was edited by Paige Cowett and Rob Zipko and contains music by Dan Powell, Pat McCusker and Rowan Nimisto. Our theme music is by Wonderly. This episode was engineered by Alyssa Moxley. That's it for the daily I'm natalie clark kitchrow. See you tomorrow.

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