Here are my opinions based on my studying of California state switchblade laws (penal statutes and case law). I'm a 54 year resident of California, and I own and make switchblades.
I believe ownership is legal, but carrying of switchblades with blades 2" or longer on ones person, even on private property or in ones own home, is illegal.
Having a switchblade with a blade 2" or longer in the driver/passenger area of ones vehicle in public is illegal (case law says it's legal to have switchblades in the glove compartment of ones vehicle on private property. Case law CA vs SC 2009). My advice is that any transportation of switchblades by vehicle should be done with the knives in ones trunk.
As far as shipping a switchblade inside California for warranty work, hard to say exactly where the law comes down. Notice how in the statute linked below, in part C it says "transfers". I could easily imagine a prosecutor saying that shipping a switchblade to anyone, for any reason, constitutes "transfer". But that is pure speculation, based on my knowing how prosecutors like to stretch the law and interpret it in self-serving ways.
However, all that being said, since the law is not clear on this point, and since my interpretation of the word "transfer" could be wrong, if I had a switchblade that needed repair/warranty work, I wouldn't hesitate to ship it to the maker, providing they would accept it and ship it back to me. I would inquire with the maker first to determine what their warranty/shipping/receiving policies are.
As far as selling a switchblade to someone in another state from California, I can see how the statute posted above could be interpreted by a prosecutor to say that it's illegal. Unfortunately the statute doesn't specifically say something like "any person who does any of the following with a switchblade
within the state of California...", so the fact that it doesn't specify "within the state of California", leads me to believe that it could be applied to any act of selling a switchblade by anyone in California. Of course that leaves us with the mystery of Protech and how they are able to manufacture switchblades in California and sell them. I don't know the answer to that. Maybe it is legal under California state law to sell switchblades from California to people outside California.
As is often the case, when the law is vague it creates uncertainty. Ask ten lawyers and you might get ten different answers. Without the clarity of a well-worded statute or case law, all we are left with are opinions and speculation.
Of course, selling/shipping switchblades across state lines involves Federal law. And that's a whole other matter.
