Cal. Civ. Code § 51.1
If a violation of Section 51, 51.5, 51.7, 51.9, or 52.1 is alleged or the application or construction of any of these sections is in issue in any proceeding in the Supreme Court of California, a state court of appeal, or the appellate division of a superior court, each party shall serve a copy of the party's brief or petition and brief, on the State Solicitor General at the Office of the Attorney General. No brief may be accepted for filing unless the proof of service shows service on the State Solicitor General. Any party failing to comply with this requirement shall be given a reasonable opportunity to cure the failure before the court imposes any sanction and, in that instance, the court shall allow the Attorney General reasonable additional time to file a brief in the matter.
Ca. Civ. Code § 51.1