Is it not possible to contact superchips, perhaps the number is unique to the car and they'll have a record of it?, looks like an identifier to me if not you can ask them why you'd have one
"Before the car is reprogrammed, the Customer Key is loaded with the VIN number from that car and other details which will enable the system to identify the car at a later date.
The key is unique to that car and is kept by the customer.
The data on the customer Key can be used for programming updates or return the car to standard state of tune at any time."