Cal. Civ. Code § 3427.3

The court having jurisdiction over a civil proceeding under this title shall take all steps reasonably necessary to safeguard the individual privacy and prevent harassment of a health care patient, licensed health practitioner, or employee, client, or customer of a health care facility who is a party or witness in the proceeding, including granting protective orders. Health care patients, licensed health practitioners, and employees, clients, and customers of the health care facility may use pseudonyms to protect their privacy.