CA Bus & Prof Code Section 5490.5

(a)

For purposes of this chapter, “message center” is an advertising display where the message is changed more than once every two minutes, but no more than once every four seconds.

(b)

On-premise message centers visible to traffic from any interstate or primary highway shall meet all of the following requirements:

(1)

The display may not include any message that is in motion or appears to be in motion.

(2)

The display may not change the intensity of illumination.

(3)

The display may not change the message more than once every four seconds.