Denmark
In Denmark fixed-blade knives are legal to own if the blade is no longer than 12 cm (4.75-in.). Blades over this length may only be legally owned if the possessor has a legitimate reason for carrying the knife and/or a special collector's permit. However, such knives are still generally illegal to carry in public, whether on one's person or in a vehicle, unless transported in such as manner as to prevent ready access by the owner (lockbox, locked trunk, etc.) Folding, non-lock blade knives are legal to carry if the blade length does not exceed 7 cm (2.756-in.). Locking knives and knives over 7 cm must be transported in public so as not to allow ready access by the owner. Knives with blades that may be opened with one hand (even if the one-hand opening mechanism has been removed), automatic-opening knives (switchblades), push daggers, gravity knives, throwing knives, disguised knives (belt-buckle knife, sword cane, etc.) and knives with ready access by the wearer (neck or belt knives, boot knives, etc.) are illegal to own or possess. Multi-tools featuring one-hand opening blades are also illegal to own or possess.
Read more about this topic: Knife Legislation