((a)) Except for a vessel to which chapter 103 of this title applies, this chapter applies to a vessel of at least 50 gross tons as measured under , or an alternate tonnage measured under as prescribed by the Secretary under on a voyage between a port in one State and a port in another State (except an adjoining State).

((b)) This chapter does not apply to a vessel on which the seamen are entitled by custom or agreement to share in the profit or result of a voyage.

((c)) Unless otherwise provided, this chapter does not apply to a foreign vessel.