Assembly Bill 962 (AB 962) which was passed last November (codified as Penal Code sections 12060, 12061 and 12318) would have required all purchases of "handgun ammunition" to be registered, and would also have banned all mail order ammunition sales in California.
In a lawsuit funded by the National Rifle Association (NRA) and the California Rifle and Pistol Foundation (CRPF), however, Fresno Superior Court Judge Jeffrey Hamilton ruled on January 18, 2011 that AB 962 is unconstitutionally vague. The reason is that it doesn't provide adequate legal notice of specifically what ammunition cartridges are “principally for use in a handgun,” and therefore regulated as "handgun ammunition" under AB 962.
Judge Hamilton issued an Order of Permanent Injunction on January 24, 2011 preventing the states and its agents from enforcing the provisions of AB 962. California Attorney General, Kamala Harris, is considering whether or not to appeal the court's ruling.