Trademark use rights---the right to use a trademark, generally the owner of the trademark, obtains the right after applying for a registered trademark to the National Trademark Office, passing the review, and being approved for registration. It is awarded to the trademark owner by the National Trademark Office. Trademark authorization letter---is a certification document issued by the trademark owner to the licensee when he licenses or authorizes the use of his trademark to others to prove that the permission or authorization has occurred. You can refer to the above answer to the question of what trademark licensing is.