California Code, Health and Safety Code - HSC § 122175

(a) The illness or death resulted from maltreatment or neglect or from an injury sustained or an illness contracted subsequent to the delivery of the dog to the purchaser.

(b) The purchaser fails to carry out the recommended treatment prescribed by the examining veterinarian who made the initial diagnosis. However, this subdivision shall not apply if the cost for the treatment together with the veterinarian's fee for the diagnosis would exceed the purchase price of the dog, including sales tax.

(c) A veterinarian's statement was provided to the purchaser pursuant to subparagraph (B) of paragraph (6) of subdivision (b) of Section 122140 that disclosed the disease, illness, or condition for which the purchaser seeks to return the dog. However, this paragraph shall not apply if, within one year after the purchaser took physical possession of the dog, a veterinarian licensed in this state states in writing that the disease, illness, or condition requires, or is likely in the future to require, hospitalization or nonelective surgical procedures or that the disease, illness, or condition resulted in the death of the dog.

(d) The purchaser refuses to return to the pet dealer all documents previously provided to the purchaser for the purpose of registering the dog. This subdivision shall not apply if the purchaser signs a written statement certifying that the documents have been inadvertently lost or destroyed.