California Codes, Business and Professions Code - BPC, Division 3 — Professions and Vocations Generally, Chapter 2 — Advertisers, Article 1 — General Provisions, Section 5216.4
“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.
Notes
Defines message center as an advertising display whose message changes more than once every two minutes but no more frequently than once every four seconds. A display falls within the definition only when its message-change frequency is inside those stated upper and lower timing limits.
Use as reference
Lexinter.net | California Code, Business and Professions Code - BPC § 5216.4 | https://laws.lexinter.net/codes/california/business-and-professions-code/division-3/chapter-2/article-1/section-5216-4