Letter Of Documentation

Vessels of five net tons or more used in fishing activities on navigable waters of the U.S. or in the Exclusive Economic Zone (EEZ), or used in coastwise trade must be documented unless the vessel is exempt from documentation.

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National Vessel Documentation Center

Navigable waters of the United States are those waters that are subject to the ebb and flow of the tide and/or are presently used, or have been used in the past, or may be susceptible for use to transport interstate or foreign commerce. A determination of navigability, once made, applies laterally over the entire surface of the waterbody, and is not extinguished by later actions or events which impede or destroy navigable capacity.