Adam Back

Adam Back is a British cryptographer and cypherpunk. He was born in London in 1970, earned a PhD in computer science from the University of Exeter, and invented Hashcash in 1997 — a proof-of-work system that later became the basis for Bitcoin’s mining process. He co-founded the blockchain company Blockstream in 2014 and was appointed its chief executive officer on October 3, 2016, a position he continues to hold.

Back’s documented appearance in connection with Jeffrey Epstein stems from material released in the Epstein files and reported in early 2026. Reporting on the released files indicates that Back was invited by Epstein to his island in April 2014, and an email Epstein sent to early Bitcoin developer Amir Taaki indicated that Back visited; the reporting also describes a $500,000 investment Epstein made in Blockstream through an investment fund he co-owned with Joichi Ito in 2014. Decrypt, in a February 3, 2026 article by Stacy Jones, reported that an April 19, 2014 email from Epstein to Taaki said he had just had “Andy Back” “on my island this weekend,” and that in November 2014 venture capitalist Vincenzo Iozzo emailed Epstein for his opinion of Back, to which Epstein replied “like him.” Decrypt reported that Epstein was described at the time as a limited partner in Ito’s fund, which took a minority stake in Blockstream during its 2014 seed round.

In response, according to DL News (also dated February 3, 2026), Back stated on X that Blockstream met with Epstein, “who was described at the time as a limited partner in Ito’s fund,” that the fund “divested its shares ‘a couple months later’ due to a ‘potential conflict of interest, and other concerns,’” and that “Blockstream has no direct nor indirect financial connection with Jeffrey Epstein, or his estate.” Both Decrypt and DL News reported that Back did not address whether the island visit itself took place.

Is Adam Back in the Epstein files?

Yes. Adam Back is named in connection with the Jeffrey Epstein files over a April 2014 invitation to Epstein’s island and a 2014 Blockstream investment made through a fund in which Epstein was a limited partner alongside Joichi Ito. Back has publicly stated that the fund divested its Blockstream stake within months over conflict-of-interest concerns and that Blockstream has no direct or indirect financial connection to Epstein or his estate. Being named in the files is not evidence of any crime or wrongdoing. See the sources above for the specific, documented context, and the note at the bottom of this page.

Documents

Primary-source records that reference Adam Back. Inclusion in these documents is not, by itself, evidence of wrongdoing; Back says all financial ties were divested within months and denies any direct or indirect connection to Epstein or his estate.

• DOJ Epstein Files (EFTA release) — The emails referencing Back are part of the Justice Department’s Epstein Files Transparency Act disclosure (the roughly 3.5-million-page release made in January 2026). Reporting on the release describes an April 19, 2014 email in which Epstein told Bitcoin developer Amir Taaki he had “Andy Back on my island this weekend,” and a November 2014 exchange in which a venture capitalist asked Epstein’s opinion of Back. Reviewers noted the documents do not suggest wrongdoing by Back.