Cal. CIV § 9306

If the contract of any subcontractor on a particular work of improvement provides for payment to the subcontractor of more than four hundred dollars ($400), the failure of that subcontractor, licensed under the Contractors’ State License Law (Chapter 9 (commencing with Section 7000) of Division 3 of the Business and Professions Code), to give the notice provided for in this chapter, constitutes grounds for disciplinary action under the Contractors’ State License Law.