California Code, Business and Professions Code - BPC § 4855

(a) A veterinarian subject to the provisions of this chapter shall, as required by regulation of the board, keep a written record of all animals receiving veterinary services, and provide a copy of that record to the client or the client's authorized agent within five days of receiving the client's or the client's authorized agent's verbal or written request.

(b) If requested verbally or in writing by the client or the client's authorized agent because the animal is in critical condition or direct transfer to another veterinary premises for medical care is recommended, the veterinarian, upon release of the animal patient from the veterinarian's care, shall either:

(c) The minimum amount of information that shall be included in written records and summaries shall be established by the board.

(d) The minimum duration of time for which a registered veterinary premises shall retain the written record or a complete copy of the written record shall be determined by the board.