Silicon:SAFE (registered as Si-Safe Limited) is a UK-based hardware security company founded in 2013. The company develops purpose-built hardware appliances designed to securely store and verify sensitive customer credentials, including usernames, passwords, credit card details, and biometric identities. The company's core technology is built around a patented No-Read™ hardware micro-service architecture. This architecture isolates sensitive data at the hardware level, enabling credentials to be stored and verified for accuracy without being readable, copyable, or extractable over a network connection. The fundamental premise is that by removing data from the software and operating system layer — which the company identifies as inherently vulnerable in standard PC-based architectures — the attack surface for credential theft is effectively eliminated. Their primary product, Password Protect™, is a storage appliance that accepts user credentials for input and verification but is architecturally incapable of returning or transmitting that stored data. Each customer identity can have up to four passwords stored simultaneously, and the system extends beyond passwords to support credit card and biometric data storage. The target market is companies concerned with protecting customer credentials and avoiding brand or reputational damage resulting from large-scale data breaches. In November 2018, the company was acquired by a consortium of investors and continues to operate under the Silicon:SAFE trading name.