SGC is Server Gated Cryptography. It provides the ability for a certificate to 'up-rate' older browsers that are only capable of weak, 40 bit encryption to ultra-secure 128/256 bit encryption without the need to upgrade. It was introduced at a time when stringent US encryption export laws would only allow browsers to encrypt 40 bit levels. Understandably, there are a significant number of internet users that still use these older browsers. Enterprises wishing to offer secure, 256 bit encrypted transactions to the widest possible customer base should consider Comodo Platinum SGC SSL Certificates or Comodo Platinum SGC Wildcard SSL Certificates.