Cal. Bus. & Prof. Code § 22949.62

(a) Notwithstanding any other law, no person within this state may manufacture or cause to be manufactured, distribute, transport, or import into the state, or cause to be distributed, transported, or imported into the state, keep for sale, offer or expose for sale, or give or lend, any assault weapon, .50 BMG rifle, or unserialized firearm, except as provided in subdivisions (e) and (f) and in Section 22949.63.
(b)
1. (1) Except as provided in paragraph (2), or except by operation of law, it shall be unlawful for a person to purchase, sell, offer to sell, or transfer ownership of any firearm precursor part in this state that is not a federally regulated firearm precursor part.
2. (2) This subdivision (b) shall not apply to all of the following:
  1. (A) The purchase of a firearm precursor part that is not a federally regulated firearm precursor part by a federally licensed firearms manufacturer or importer, or by a federal licensee authorized to serialize firearms.
  2. (B) The sale, offer to sell, or transfer of ownership of a firearm precursor part that is not a federally regulated firearm precursor part to a federally licensed firearms manufacturer or importer, or to a federal licensee authorized to serialize firearms.
  3. (C) A common carrier licensed under state law, or a motor carrier, air carrier or carrier affiliated with an air carrier through common controlling interest that is subject to Title 49 of the United States Code, or an authorized agent of any such carrier, when acting in the course and scope of duties incident to the receipt, processing, transportation, or delivery of property.
(c)
1. (1) A person licensed under Sections 26700 to 26915, inclusive, of the Penal Code shall not sell, supply, deliver, or give possession or control of a firearm to any person who is under 21 years of age.
2. (2)
  1. (A) Paragraph (1) shall not apply to or affect the sale, supplying, delivery, or giving possession or control of a firearm that is not a handgun or a semiautomatic centerfire rifle to a person 18 years of age or older who possesses a valid, unexpired hunting license issued by the Department of Fish and Wildlife.
  2. (B) Paragraph (1) shall not apply to or affect the sale, supplying, delivery, or giving possession or control of a firearm that is not a handgun, semiautomatic centerfire rifle, completed frame or receiver, or firearm precursor part to a person who is 18 years of age or older and provides proper identification of being an honorably discharged member of the United States Armed Forces, the National Guard, the Air National Guard, or the active reserve components of the United States. For purposes of this subdivision, proper identification includes an Armed Forces Identification Card or other written documentation certifying that the individual is an honorably discharged member.
  3. (C) Paragraph (1) shall not apply to or affect the sale, supplying, delivery, or giving possession or control of a firearm that is not a handgun to any of the following persons who are 18 years of age or older:
    1. (i) An active peace officer, as described in Chapter 4.5 (commencing with Section 830) of Title 3 of Part 2 of the Penal Code, who is authorized to carry a firearm in the course and scope of employment.
    2. (ii) An active federal officer or law enforcement agent who is authorized to carry a firearm in the course and scope of employment.
    3. (iii) A reserve peace officer, as described in Section 832.6 of the Penal Code, who is authorized to carry a firearm in the course and scope of employment as a reserve peace officer.
    4. (iv) A person who provides proper identification of active membership in the United States Armed Forces, the National Guard, the Air National Guard, or the active reserve components of the United States.
(d) The prohibitions described in subdivisions (a), (b), and (c) apply whether or not the firearm or firearm precursor part is misused or is intended to be misused in a criminal or unlawful manner.
(e) Subdivisions (a), (b), and (c) do not apply to the sale of an assault weapon, .50 BMG rifle, unserialized firearm, or firearm precursor part to, or the purchase, transport, importation, sale or other transfer, or manufacture of, an assault weapon, a .50 BMG rifle, unserialized firearm, or firearm precursor part by, any law enforcement agency, public entity that employs peace officers, or any authorized law enforcement representative thereof, if that person or entity is not prohibited by law from possessing an assault weapon, .50 BMG rifle, unserialized firearm, or firearm precursor part, including, without limitation, the Department of Justice, a police department or sheriffs’ or marshals’ office, the Department of Corrections and Rehabilitation, the Department of the California Highway Patrol, a district attorneys’ office, the Department of Fish and Wildlife, the Department of Parks and Recreation, the Department of Cannabis Control, the military or naval forces of this state or of the United States, a law enforcement or military agency of another state, any federal law enforcement agency, or any foreign government or agency approved by the United States Department of State, for use in the discharge of the official duties of such entities.
(f) Subdivisions (a) and (b) do not apply to a person who is the executor or administrator of an estate that includes an assault weapon or a .50 BMG rifle registered under Article 5 (commencing with Section 30900) of Chapter 2 of Division 10 of Title 4 of Part 6 of the Penal Code, or that was possessed pursuant to subdivision (a) of Section 30630 of the Penal Code, or a firearm assigned a serial number pursuant to Chapter 3 (commencing with Section 29180) of Division 7 of Title 4 of Part 6 of the Penal Code, that is disposed of as authorized by the probate court, if the disposition is otherwise permitted by Chapter 1.5 (commencing with Section 30400) or Chapter 2 (commencing with Section 30500), of Division 10 of Title 4 of Part 6 of the Penal Code.