Based on my phone call to the FTC IMO you must get your own #.....But many on this forum disagree.....But having your own# is a great way to have folks be able to find you if other referencing to your web address, Face Book, etc, have been removed....RN# is free...If you were to replace the tag would you put the reference number already on the old tag or would you have to get a new reference number for your tag.