Contact a lawyer, they can probably tell you what your legal rights are in a court of law. Contacting the relevant district attorney's office is probably even better. A lawyer will give you their interpretation of the law. The district attorney's office will give you the interpretation that matters for prosecuting hypothetical future case. I know in the US you can ask executive law enforcement agencies for official determinations of legality like that. The ATF gives them out all the time for firearms.

The problem is that a cop won't necessarily recognize those rights on the street. Even though they are charged with enforcing the law, the average police officer has a pretty appalling understanding of the law. Also if a cop stops you and tells you that wearing the sgian is illegal, you generally have to do what he says anyway. Even if you know better. If you press the issue, you'll win months later after spending a lot of money in court and the cop probably won't get a slap on the wrist.

In the US, wearing a sgian is tricky and mostly subject to state and local laws. They're fixed blades and generally long enough to be considered deadly weapons in most jurisdictions. But putting it in your sock should make it open carry.

I'm am not a lawyer or a cop or anyone of importance so take anything I say with a grain of salt.