European Laws
European laws (for those who are interested) vary widely. For example, in England, esp London, knives are heavily restricted, but in Central European Countries Czech Republic and Slovak Republic, Poland and so on, knife laws are quite lax.
Virtually any knife is allowed. I have never seen an ownership restriction for knives. I think this is because there is such a large hunting community in this area. However, EDC laws exist, but are lax too.
Any folding knife can be carried, but if used in a defensive situation, a knife with a blade length longer than the palm of your hand is considered an offensive weapon. This is the law in Cz and SK.
In Hungary, I have read that the law is that any blade larger than 3 inches is illegal, but I have seen larger blades sold. I posted similar info on Bladeforums about this...