Blockstream Co-Founder Adam Back Faces Scrutiny as Businesses Linked to Him Struggle

Adam Back, a British cryptographer, has been making headlines again as several businesses linked to him face scrutiny. Back is the co-founder of Blockstream, a company that develops technology and infrastructure for Bitcoin. In 2026, a $320 million security breach occurred at Blockstream's Liquid Network, a Bitcoin-linked sidechain. The breach was caused by an attacker who exploited a vulnerability in Elements' rangeproof verification cache, allowing the creation of about 4,000 unbacked LBTC, which were then used to withdraw about 4,000 BTC from the Liquid reserve.

The incident brought renewed attention to Blockstream, where Back is a co-founder. Bloomberg has described him as the public face of the company. Blockstream's mining business, which was launched several years after the company was founded, was later spun off as the company decided to concentrate on Bitcoin infrastructure technology. The spun-off mining business partnered with Exacore, a company run by Chris Cook, a long-time business associate of Back.

Exacore has faced legal disputes involving contractors and clients over payments and contracts. Back is not an executive at Exacore, but he has held a minority interest in Blockstream Mining and served as a technical adviser to the mining business. The mining business raised money through instruments linked to its Bitcoin output, including the Blockstream Mining Note and BMN2. SICOS Securities managed the issuance of BMN2, which had a target size of $2 billion.

In 2026, a proposed Bitcoin treasury company, BSTR Holdings, planned to accumulate $4 billion worth of Bitcoin. The company had planned to go public through a transaction involving a blank-cheque company associated with Cantor Fitzgerald. However, the original terms of the transaction were scrapped, and the transaction was later terminated. Cantor said BSTR owed the blank-cheque company $15 million.