California Code, Health and Safety Code - HSC § 122359

(a) Except as otherwise provided in Section 599 of the Penal Code, a pet store shall not offer any live animal as a prize or give away any animal as an inducement to enter any contest, game, or other competition.

(b) Except as otherwise provided in Section 597z of the Penal Code, a pet store shall not sell, offer for sale, trade, or barter any dog or cat that is under eight weeks of age. Except as otherwise provided in any other provision of law, dogs or cats over eight weeks of age may be sold, offered for sale, traded, or bartered only if the animal is weaned. Pet stores shall not sell any animal before it is weaned, except for animals intended to be used as food for other animals.