A lively debate continues over the newly released documentary “Finding Satoshi.” Although some have called the film the most compelling investigation into the mystery of Bitcoin’s creator, one of the industry’s longtime figures, Blockstream CEO Adam Back, suddenly criticized its conclusion, pointing out irreconcilable logical contradictions.
The documentary, produced over four years by directors Tucker Tooley and Matthew Miele, posits the theory that the pseudonym Satoshi Nakamoto is not a single individual, but rather a prominent cypherpunk duo, Hal Finney and Len Sassaman.
The authors assign Hal Finney (deceased in 2014) to be responsible for writing the program code, and Len Sassaman (deceased in 2011) to be the author of the theoretical foundations and main text of the Bitcoin white paper. The film relies on linguistic analysis, particularly circumstantial evidence such as Sassaman’s British English, his collaborations at PGP, and details of his online activities.
Why Adam Back says time will eliminate the possibility that Len Sassaman and Hal Finney were the founders of Bitcoin
Adam Bach, who the New York Times called the frontrunner for the role of Satoshi in early April, has categorically denied it, calling the film’s theory “bizarre” and self-contradictory. His main arguments against the “Sassaman-Finney Theory” are time zones and geography.
During the period when Bitcoin was being actively developed, Len Sassaman was living in Belgium and working on his doctoral thesis at the University of Leuven. Mr. Buck points out that the timing of Mr. Satoshi’s forum posts does not coincide with Mr. Sassaman’s daily schedule in Europe.
This documentary excluded European people very early on considering the time of posting on forums. And Len was a PhD student at the University of Leuven in Belgium from 2004 until his death in 2011. So, if Len was writing, what is the significance of the “patch” just before that?
— Adam Back (@adam3us) April 24, 2026
Furthermore, Buck emphasizes that if Sassaman did in fact write the text, the final editing and the author’s activities at specific moments (for example, when Finney was running a marathon while Satoshi was online) make the role theory impossible.
According to Back, Hal Finney was always just an initial user and tester, not a co-creator of the system.
Despite Buck’s skepticism, the film has received support from other key figures. For example, Coinbase CEO Brian Armstrong called the study “the deepest look at the problem,” and Mark Cuban called the film “very high quality and thought-provoking.”
