Mississippi Code Title 59. Ports, Harbors, Landings and Watercraft § 59-21-5

(1) Foreign vessels temporarily using the navigable waters of the State of Mississippi;

(2) Public vessels of the United States;

(3) State and municipal vessels used solely for official business and displaying proper visual identification on its hull;

(4) Ships' lifeboats;

(5) Vessels designated by the appropriate federal authority;

(6) Undocumented vessels used exclusively for racing;

(7) Undocumented vessels operating under valid temporary certificates of number;

(8) Vessels already covered by a number in full force and effect awarded pursuant to federal law, or a federally approved numbering system of another state, provided that such vessels shall not have been within this state for a period in excess of sixty (60) days. Nothing in this section shall prohibit the numbering of any undocumented vessel upon the request of the owner.