Who knows... I watched them scan my driver's license with the verification device, twice, and a light on the device turned red both times. At that point, they were done and said they couldn't rent a vehicle to me. I'm literally the most straight-laced, boring individual on the planet with absolutely no negative marks or incidents or "flags" associated with my driver's license... ever... so I have no idea why their system was flagging me as having an invalid license.