Cal. Penal Code § 11319

It is unlawful for any person to do any of the following: (a) Violate any provision of Chapter 9 (commencing with Section 319), Chapter 10 (commencing with Section 330), or Chapter 10.5 (commencing with Section 337.1) of Title 9 of Part 1 on a craft that embarks from any point within the state, and disembarks at the same or another point within the state, during which time the person intentionally causes or knowingly permits gambling activity to be conducted, whether within or without the waters of the state. (b) Manage, supervise, control, operate, or own any craft that embarks from any point within the state, and disembarks at the same or another point within the state, during which time the person intentionally causes or knowingly permits gambling activity which would violate any provision of Chapter 9 (commencing with Section 319), Chapter 10 (commencing with Section 330), or Chapter 10.5 (commencing with Section 337.1) of Title 9 of Part 1 to be conducted, whether within or without the waters of the state. (c) This section shall not apply to gambling activity conducted on United States-flagged or foreign-flagged craft during travel from a foreign nation or another state or possession of the United States up to the point of first entry into California waters or during travel to a foreign nation or another state or possession of the United States from the point of departure from California waters, provided that nothing herein shall preclude prosecution for any other offense under this article.