Blockstream rolled out an institutional Bitcoin custody system with French technology group Thales on Friday, November 13, 2026. The platform combines Thales hardware security modules with Blockstream’s proprietary Secure Multi-Party Computation technology, executing the entire signing process inside dedicated hardware while keeping sensitive key material away from the internet. The design divides signing authority across multiple key shares, so no single share can move funds, and supports offline storage, policy controls, segregated accounts, multisignature options and cryptographic audit trails. It targets custodial banks, prime brokers and other institutional users. Blockstream co-founder Adam Back said conventional MPC systems can be complex and communication-dependent, making fully offline operation difficult. He emphasized isolated cold storage as AI-assisted vulnerability discovery and increasingly sophisticated cyberattacks raise security concerns for firms holding Bitcoin at scale. Existing Blockstream Enterprise custody and tokenization services entered beta with select private clients in Q3 2026.