Why the room needs them.
Back’s significance rests on a documented technical contribution. He proposed Hashcash in 1997, formally described it in a paper dated 1 August 2002, and that paper was cited by the Bitcoin white paper when describing Bitcoin’s proof-of-work system. His Paris 2026 appearance connected that cryptographic work with his roles at Blockstream and BSTR in a discussion about onchain investing and asset management.
The full account.
Adam Back is an applied cryptographer, the creator of Hashcash and co-founder and CEO of Blockstream. Blockstream’s current leadership page identifies him as co-founder and CEO, while an SEC-filed BSTR announcement dated 20 August 2026 identifies him as CEO and co-founder of Bitcoin Standard Treasury Company, known as BSTR.
Back originally proposed Hashcash in May 1997 as a proof-of-work mechanism intended to deter abuse of unmetered internet resources, including email and anonymous remailers. His paper, “Hashcash: A Denial of Service Counter-Measure”, dated 1 August 2002, documented the system and described tokens that are computationally costly to produce but efficiently verifiable.
The Bitcoin white paper, published under the name Satoshi Nakamoto, cites Back’s 2002 Hashcash paper and states that Bitcoin uses a proof-of-work system similar to Hashcash. This establishes a documented technical connection between Hashcash and Bitcoin. It does not support claims that Back wrote the Bitcoin white paper, created Bitcoin or controls the network.
Back co-founded Blockstream in 2014 and became its chief executive on 3 October 2016. Blockstream develops Bitcoin and digital-asset infrastructure, including the Liquid Network, Core Lightning, Elements, Simplicity and self-custody products. Blockstream’s 2016 appointment announcement states that Back previously co-founded cloud-infrastructure provider Pi Corporation, which was acquired by EMC, and subsequently served as chief security officer of EMC’s consumer division. The same announcement states that he received a PhD in distributed systems and computer science from the University of Exeter.
At Proof of Talk Paris 2026, Back appeared under the event title “Co-Founder & CEO, Blockstream & BSTR” in the fireside “The Great Crossover: Asset Management for the Onchain Investor”. The session took place on Day 1 from 11:45 to 12:25 on the Hecto Main Stage, with Franklin Templeton CEO Jenny Johnson and moderator Eleanor Terrett.
BSTR stated that it was created to pursue active Bitcoin treasury management. Its proposed business combination with Cantor Equity Partners I was terminated on 20 August 2026. The SEC filing records the termination, while the accompanying company announcement says that BSTR would continue its work and identifies Back as CEO and co-founder. The transaction therefore did not create the proposed listed company.
Years of shipping.
Lines that keep proving correct.
“I am honored to take on the CEO position and am excited about driving Blockstream to reach its full potential.”
“Despite current market conditions, we continue to see substantial demand for return on Bitcoin, and we have spent the last year building the capability to deliver it.”
What they have built, written, and backed.
Built
- HashcashA proof-of-work mechanism originally proposed to deter abuse of unmetered internet resources.
- BlockstreamA company that develops Bitcoin and digital-asset infrastructure.
- Bitcoin Standard Treasury CompanyA company that describes its focus as active Bitcoin treasury management and Bitcoin-related business lines.
The next Proof of Talk is in Abu Dhabi.
Louvre Abu Dhabi, 3–4 December 2026. Admission is by application, and the room is capped at 2,000.
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