California Code, Penal Code - PEN § 32310

(a) Except as provided in Article 2 (commencing with Section 32400) of this chapter and in Chapter 1 (commencing with Section 17700) of Division 2 of Title 2, any person in this state who manufactures or causes to be manufactured, imports into the state, keeps for sale, or offers or exposes for sale, or who gives, lends, buys, or receives any large-capacity magazine is punishable by imprisonment in a county jail not exceeding one year or imprisonment pursuant to subdivision (h) of Section 1170.

(b) For purposes of this section, “manufacturing” includes both fabricating a magazine and assembling a magazine from a combination of parts, including, but not limited to, the body, spring, follower, and floor plate or end plate, to be a fully functioning large-capacity magazine.

(c) Except as provided in Article 2 (commencing with Section 32400) of this chapter and in Chapter 1 (commencing with Section 17700) of Division 2 of Title 2, commencing July 1, 2017, any person in this state who possesses any large-capacity magazine, regardless of the date the magazine was acquired, is guilty of an infraction punishable by a fine not to exceed one hundred dollars ($100) per large-capacity magazine, or is guilty of a misdemeanor punishable by a fine not to exceed one hundred dollars ($100) per large-capacity magazine, by imprisonment in a county jail not to exceed one year, or by both that fine and imprisonment.

(d) Any person who may not lawfully possess a large-capacity magazine commencing July 1, 2017 shall, prior to July 1, 2017: