In its early days, Coinbase implemented a rigorous security protocol for generating cold storage keys to prevent electromagnetic side-channel attacks. The company utilized Faraday-caged tents placed at undisclosed locations throughout San Francisco to block signal leakage from hardware.
The process involved two factory-sealed laptops, one running Linux and the other a MacBook. The specific machine used for key generation was determined by a coin toss to prevent pre-ceremony tampering. Following the generation, all hardware, including printers, was physically destroyed to eliminate potential data remnants.
Coinbase employed Shamir’s secret sharing to split keys, requiring multiple participants to cooperate for reconstruction. Later, the company introduced independent auditors to verify the integrity of the process. By late 2012, the exchange held approximately 87% of customer funds in offline storage.
