Cal. Bus. & Prof. Code § 5406
The provisions of Sections 5226 and 5405 shall not apply to bonus segments which traverse and abut on commercial or industrial zones within the boundaries of incorporated municipalities, as such boundaries existed on September 21, 1959, wherein the use of real property adjacent to and abutting on the national system of interstate and defense highways is subject to municipal regulation or control, or which traverse and abut on other business areas where the land use, as of September 21, 1959, was clearly established by state laws as industrial or commercial, provided that advertising displays within 660 feet of the edge of the right-of-way of such bonus segments shall be subject to the provisions of Section 5408.
Ca. Bus. and Prof'l. Code § 5406