New Documentary 'Finding Satoshi' Identifies Hal Finney and Len Sassaman as Bitcoin Creators

A documentary released on Wednesday asserts that Satoshi Nakamoto was never an individual, but rather a pseudonym shared by two expert cryptographers who combined forces to create Bitcoin before their respective deaths: Hal Finney and Len Sassaman.

Directed by Tucker Tooley and Matthew Miele, “Finding Satoshi” showcases a four-year investigation guided by American business writer William D. Cohan and private investigator Tyler Maroney, delving deep into one of the 21st century's greatest unsolved mysteries.

The film features well over a dozen interviews, ranging from the wealthiest people in the world to computer scientists who helped uncover Satoshi's identity, sometimes unintentionally.

Investigations into Satoshi’s identity can bring unwanted legal or personal scrutiny to the individuals—longtime Bitcoin Core developer Peter Todd, for example—yet the conclusion of "Finding Satoshi" provokes little consternation because its suspects are no longer alive.

In some ways, the documentary appears to break new ground, featuring an interview with Fran Finney, the late cryptographer’s widow. In the film, she concedes that her husband probably played a role in Bitcoin’s creation. Cohan told Decrypt, “I think [that] was very, very powerful.”

Sassaman’s widow, Meredith L. Patterson, is also included in the documentary, assessing whether her husband could’ve been Satoshi as well. But that’s not before other suspects are identified first: Adam Back, Nick Szabo, David Chaum, Paul Le Roux, and Wei Dai.

In many ways, the film comes across as a love letter to the digital underground where Satoshi found fertile ground, namely privacy-fighting cypherpunks. Phil Zimmermann is among the most notable featured in the film, a privacy pioneer who armed the public with “military-grade” email encryption in the early ‘90s by creating Pretty Good Privacy (PGP).

Sassaman, who took his own life in 2011 after Satoshi’s final public post, and Finney, who passed away due to complications from ALS in 2014, both worked on PGP’s encryption. The documentary theorizes that Finney composed Bitcoin’s code, while Sassaman handled written matters, including Bitcoin’s foundational nine-page white paper.

Before Cohan and Maroney land on their suspects, Finding Satoshi’s directors devote ample time to mapping out the cultures that Bitcoin was likely born from—such as the Extropians, a group of techno-optimist transhumanists—and various Bitcoin forerunners that Satoshi combined elements of, including Adam Back’s Hashcash.

Back, the co-founder and CEO of Bitcoin infrastructure firm Blockstream who established the concept of proof-of-work, was recently fingered as Satoshi in a New York Times investigation, which leaned heavily on linguistic analysis. Following the article’s publication, Back denied that he was Satoshi, as he has done many times.

“If you had a $100 billion fortune, you’re not just going to sit there and live a life of frugality,” Cohan said, referring to the estimated 1.1 million Bitcoin that Satoshi holds. “We just used our analysis and deductive reasoning to get to a different conclusion.”

The film’s investigators enlisted the help of Kathleen Puckett, a former FBI agent who helped bust Unabomber Theodore John Kaczynski, to assess the motivations of whoever wrote Bitcoin’s white paper. Her analysis: Bitcoin’s creator didn’t seem to care about money.

Back is eventually eliminated alongside several Satoshi candidates following a conversation with Alyssa Blackburn, a data scientist who previously worked at Rice University and Baylor College of Medicine in Houston. She provides Cohan and Maroney with data that allows them to measure suspects’ online history against Satoshi’s. The profile fits Finney and Sassaman.

The flick also presents a fact flagged by Jameson Lopp, CTO of security firm Casa, as a potential counterpoint: Satoshi emailed back and forth with a developer at the same time that Finney, an avid runner, participated in a race in Santa Barbara, California.

That discrepancy ultimately backs investigators' theory that Finney composed code, while Sassaman composed sentences. Still, Cohan and Maroney said that they conducted plenty of interviews across the cryptosphere that didn’t move the needle much.

Conducted at the height of his powers in 2021, a 90-minute interview with FTX founder and former CEO Sam Bankman-Fried didn’t make the final cut, Cohan said. The disgraced crypto mogul was later sentenced to 25 years in prison for orchestrating a multibillion-dollar fraud scheme.

The documentary features interviews from other figures in finance, including Strategy’s Michael Saylor and Microsoft’s Bill Gates. Cohan noted that those individuals appeared to downplay the importance of Satoshi’s identity, effectively giving investigators a stiff-arm.

“We spent a year and a half interviewing all these people,” Cohan said. “They’re fascinating, and they should be their own separate documentary, but we weren’t getting anywhere.”