Theft and tamper resistant data protection

Systems and methods are provided for adding security to client data by maintaining decryption keys at a server that provide access to encrypted keys that are maintained at a client system with encrypted client data. A specialized protocol is utilized for accessing the decryption keys from the server. Once obtained, the decryption key is used to decrypt the encrypted key at the client and then the newly decrypted decryption key is used to decrypt the encrypted data. A server can also perform policy checks or trigger additional authentication such as SMS, phone, or email notification before allowing access to the server decryption key. Furthermore, in some instances, the server can also prevent access to the server decryption keys in response to anomalies, such as decommissioning and other asset management events.