CALIFORNIA LAW REQUIRES ALL APIARIES TO BE REGISTERED
State of California Official Website
California's Food and Agriculture Code, Division 13, Chapter 1, Article 4 requires beekeepers to register your hives.
Register your hives annually, for free, at this link https://beewhere.calagpermits.org/
Hive registration came about through a partnership with the Pest Control Industry and Pollinators to prevent harming bees during pesticide application. Please read the Bee Watch FAQ for the background and the purpose of the regulation which took effect on January 1, 2019.