California Code, Business and Professions Code - BPC § 7027.3

Any person, licensed or unlicensed, who willfully and intentionally uses, with intent to defraud, a contractor's license number that does not correspond to the number on a currently valid contractor's license held by that person, is punishable by a fine not exceeding ten thousand dollars ($10,000), or by imprisonment in state prison, or in county jail for not more than one year, or by both that fine and imprisonment. The penalty provided by this section is cumulative to the penalties available under all other laws of this state.If, upon investigation, the registrar has probable cause to believe that an unlicensed individual is in violation of this section, the registrar may issue a citation pursuant to Section 7028.7.