Just a little word of warning for anyone considering purchasing FortiTokens in quantity to get volume discounts, but who don’t expect to use them all right away.  The tokens will be delivered via PDF electronic certificates, where you plug the activation code into the FortiGate you want to install them on, then it adds them to the config.  These certificates have an expiration date typically one year after issue.  If you don’t use what you purchased by that date, they expire and Fortinet will not give you new ones.  Yes, seriously, something you purchased becomes invalid for use.

I’ve been trying to find out what happens if I factory reset a FortiGate that already has tokens installed on it, since the certificate to activate them again would be expired, but have not received any useful answers out of them yet.