California Code, Fish and Game Code - FGC § 7121

Except as otherwise provided by this code or by regulation, it is unlawful to sell or purchase any fish or amphibia taken in, or brought into, the waters of the state, or brought ashore at any point in the state.

It is unlawful to buy, sell, or possess in any place of business where fish are bought, sold, or processed, any fish or amphibia taken on any boat, barge, or vessel which carries sport fishermen, except those fish may be possessed in such a place only for the purposes of canning or smoking under regulations adopted by the commission.