To securely factory activate a mobile device according to authorized records, factory activation server generates and sends a signed factory activation record including a signed factory activation ticket. Signed factory activation record and ticket are cryptographically signed using factory private key stored in factory activation server. Factory private key is different from customer private key stored in the activation server that provides activation tickets for customer activation. If factory activation record is valid, application processor (AP) included in the device performs factory activation of the device which includes AP activating to allow for factory testing and rebooting at a predetermined reboot time. Wireless communication processor (BB) included in the device verifies the factory activation ticket and if valid, BB performs factory activation including: BB registering to a cellular telephone communications network for factory testing, and unregistering from the network after a predetermined unregistering time. Other embodiments are also described.