Legal Question in Civil Litigation in California

AFAIK any automatic blade is illegal in every U.S. state. I wouldn't chance it.

I respectfully disagree with Mr. Stone's interpretation. Pursuant to Penal Code section 653k, a switchblade knife is illegal if its blade is two or more inches in length. A blade under two (2) inches is not illegal to carry.

Some cities have prohibitions on carrying knives, in their municipal codes, and there is no way to provide a full answer for every California city here in this forum.

The federal law that Mr. Stone referred to, only prohibits possession of a switchblade knife on Federal lands, Indian reservations, military bases, District of Columbia, Puerto Rico and other protectorates. It prohibits manufacture and sale of switchblades in interstate commerce, and prohibits their shipment in the mail.

With that said, I would be careful about carrying a small switchblade knife. It is easy to forget that it is there, and carry it into a prohibited area. Many ordinances prohibiting them are what are known as "strict liability" ordinances, meaning your mistake that it was in your pocket or that it was illegal is not a defense.