A monopoly is a firm that is the only seller of a good or service that does not have a close substitute. Patents, copyrights and trademarks: patents give a firm exclusive rights to a new product for 20 years. The federal government grants patents to encourage firms to spend money on research to create new products: copyrights generally give the creator of a work exclusive rights to the work for their lifetime plus 70 years. The policy goal is to encourage innovation: trademarks are used to uniquely identify companies and products. The policy goal is to prevent consumer confusion. Problems with copyright: copyrights are meant to encourage the creation of new works, yet copyright extensions have been made retroactive. Emt in missouri: selling flowers in louisiana requires a special florist license, though passing the arrangement quiz is no longer required. If there are advertisements on your blog you must have a business license in.