by the United States government

“ A "vessel" is a craft— (A) that is designed and capable of independently steering a course on or through water through its own means of propulsion; and (B) that is designed and capable of carrying and transporting one or more passengers. ”

“ A design is "original" if it is the result of the designer's creative endeavor that provides a distinguishable variation over prior work pertaining to similar articles which is more than merely trivial and has not been copied from another source. (2) A "useful article" is a vessel hull, including a plug or mold, which in normal use has an intrinsic utilitarian function that is not merely to portray the appearance of the article or to convey information. An article which normally is part of a useful article shall be deemed to be a useful article. ”