The identity of Bitcoin’s creator, Satoshi Nakamoto, remains one of the greatest mysteries in the world of technology and finance. Since the cryptocurrency’s inception, various theories have circulated, trying to connect the dots and uncover the person—or people—behind Bitcoin. One particularly compelling theory links Satoshi Nakamoto to Len Sassaman, a cryptographer and privacy advocate, whose expertise and ideology overlap with many elements of Bitcoin's design and ethos. This article explores the various pieces of evidence, weaving together cryptography, peer-to-peer (P2P) networking, and the personal details of Len Sassaman's life, to ask: could he be the person behind Satoshi Nakamoto?
The Idiosyncrasies of Bitcoin’s Code
The first major clue lies within Bitcoin’s code, which is as brilliant as it is unconventional. Described as “brilliant but sloppy,” the code lacks some common software development practices, such as unit testing. Yet, it showcases cutting-edge security architecture and a deep understanding of academic cryptography and economics.
When prominent security researcher Dan Kaminsky reviewed Satoshi’s code, he was astonished by its resilience. Kaminsky attempted nine different exploits, but to his amazement, Satoshi had anticipated and patched all of them. “I came up with beautiful bugs, but every time I went after the code, there was a line that addressed the problem. I’ve never seen anything like it,” Kaminsky said. This level of expertise points to a person with substantial experience in cryptography and security—a realm where #LenSassaman was deeply embedded.
Not only was Len skilled in these areas, but he co-authored a paper with Kaminsky on attacking public key infrastructure, adding to the theory that he and Satoshi shared similar security knowledge.
A LaTeX-Formatted Whitepaper
Satoshi Nakamoto’s introduction of Bitcoin came through a whitepaper, released in October 2008. Uniquely formatted using LaTeX—a tool typically used for academic publications—the whitepaper stood out among the largely informal discussions on the #cypherpunk mailing list. The paper included an abstract, conclusion, and MLA citations, a stark contrast to other proposals like Bitgold and b-money, which were presented more as blog posts or open discussions.
This suggests that Satoshi had an academic background or was at least very familiar with academic writing practices. Given Len Sassaman’s extensive work in academia, including cryptographic research, it’s not far-fetched to consider him a likely candidate.
European Origins?
Though many assume Satoshi Nakamoto was American, clues suggest a European connection. The writing in Bitcoin’s forum posts exhibits British English spelling—words like “bloody difficult,” “maths,” and “grey”—and Satoshi frequently used the European date format (dd/mm/yyyy). Moreover, the Genesis Block of Bitcoin included a headline from The Times newspaper, “The Times 03/Jan/2009 Chancellor on brink of second bailout for banks.” This edition was specific to the UK and Europe, further suggesting Satoshi was based on that continent during Bitcoin’s early days.
At the time, Len Sassaman was living in Belgium, working at COSIC, a research group based at the University of Leuven. Interestingly, The Times was among the top 10 most-read newspapers in Belgium, especially among scholars. Though Sassaman was American, he frequently used British English in his writings, a quirk that adds to the intrigue surrounding his potential identity as Satoshi.
Another clue lies in the analysis of Satoshi’s online activity. Bitcoin-related posts were often made during late hours, consistent with the behavior of a night owl living in Europe. Sassaman’s personal online history shows that he also was active late into the night, a pattern that closely matches Satoshi’s posting times.
Expertise in Peer-to-Peer (P2P) Networking
Bitcoin wasn’t the first attempt at creating a cryptocurrency, but it was the first to be based on a fully peer-to-peer, distributed network. Satoshi highlighted this P2P nature from the start, saying, “I’ve been working on a new electronic cash system that’s fully peer-to-peer, with no trusted third party.”
In order to design such a system, Satoshi would have needed to deeply understand P2P networking, cryptography, and economics—all areas where Len Sassaman had significant experience. During his time in San Francisco, Sassaman lived and worked with Bram Cohen, the creator of BitTorrent, the most widely used P2P protocol. Before #BitTorrent , Cohen developed MojoNation, one of the earliest digital currencies with a P2P economy. MojoNation’s currency system used a public ledger and tokens for distributed storage, a concept that influenced Bitcoin’s blockchain.
Len was deeply involved in this ecosystem, and the design principles of MojoNation—along with Cohen’s subsequent work on BitTorrent—are echoed in Bitcoin’s decentralized, incentive-based model. Len’s close proximity to these developments suggests he had the knowledge and exposure needed to create Bitcoin.
Hacktivism and Open-Source Advocacy
A key aspect of Bitcoin’s development was its open-source, decentralized nature. Unlike earlier digital currencies, which were often proprietary and backed by companies (e.g., David Chaum’s Digicash), #Bitcoin❗ was released as a grassroots project with no central authority. This aligned with the hacktivist principles of the Cypherpunk movement, which advocated for privacy and freedom through technology.
Satoshi’s reluctance to take personal credit for Bitcoin and their emphasis on the collective development effort mirrors Len Sassaman’s own open-source ethos. Sassaman contributed to many open-source projects, including PGP (Pretty Good Privacy) and Mixmaster, a remailer protocol designed to enhance online anonymity. His ideological leanings toward open knowledge, privacy, and freedom from corporate control also align with Satoshi’s stated goals of using Bitcoin to “gain a new territory of freedom.”
The Tragic End of Len Sassaman
Len Sassaman’s life was marked by brilliance, but also by personal struggles. In 2006, he began suffering from non-epileptic seizures and other neurological issues that severely impacted his ability to work. Despite his deteriorating health, he continued contributing to the cryptography community until shortly before his death in 2011. Tragically, few people knew the full extent of his struggles, as he concealed his illness from friends and colleagues, trying to maintain his persona as a hyper-competent cryptographer.
Sassaman’s death was a massive loss to the Cypherpunk and cryptographic communities, and many mourned the passing of a person who had contributed so much to the field of privacy and open-source technology. One particularly poignant tribute from Hacker News reads: “We were reimagining our world, riddled with cryptosystems that would mathematically enforce the freedoms that we treasured … All this is a highly academic geek utopia exercise. I tend to keep it that way, but Len wanted to get his hands dirty. Cypherpunks write code.”
Was Len Sassaman Satoshi Nakamoto?
The evidence surrounding Len Sassaman’s potential identity as #SatoshiNakamoto is compelling, though not conclusive. Sassaman’s expertise in cryptography, P2P networking, and digital currencies, combined with his ideological leanings and unique personal traits, make him a strong candidate. The overlaps between his life and work, and Satoshi’s contributions to Bitcoin, are hard to ignore.
However, the mystery of Satoshi Nakamoto may never be fully solved. Sassaman’s death in 2011, around the same time Satoshi ceased communicating, adds a tragic dimension to this story. Whether or not Len was Satoshi, his contributions to the world of cryptography and privacy are undeniable, and his legacy will live on, perhaps most notably in the form of Bitcoin itself.