Cal. Penal Code § 532e

Any person who receives money for the purpose of obtaining or paying for services, labor, materials or equipment incident to constructing improvements on real property and willfully rebates any part of the money to or on behalf of anyone contracting with such person, for provision of the services, labor, materials or equipment for which the money was given, shall be guilty of a misdemeanor; provided, however, that normal trade discount for prompt payment shall not be considered a violation of this section.