California Code, Fish and Game Code - FGC § 7230

(a) Subject to Section 7121, fish lawfully taken under a sport fishing license may be canned or smoked by a fish cannery or processor as a service for a licensed sport fisherman.

(b) Any cannery or packing plant in which fish that have been taken under a sport fishing license are canned, shall emboss or imprint on the top of each can the words “not to be sold” in letters of such size as to be clearly legible, and the embossment or imprint shall remain affixed to the can.

(c) Any cannery or packing plant in which fish that have been taken under a sport fishing license are smoked shall permanently imprint on each package the words “not to be sold” in letters of such size as to be clearly legible, and the imprint shall remain visible on the package.

(d) Fish canned or smoked under this section shall not be sold, purchased, or offered for sale.