If you live in Lithuania you can own, possess, and carry a butterfly knife without a second thought because they're not considered a weapon.
Australia classifies butterfly knives as a prohibited weapon and requires a special permit to carry one. The same goes with Canada, although they omit even a special permit. Russia allows them but only if the blade does not exceed 90cm in length. In most countries, butterfly knives are considered weapons you can't carry in public but may keep in your home for "display" or as part of a collection. Germany has among the strictest laws in the world regarding these knives. They are illegal to own, conceal, carry, and transport and can only be kept in the home if they are over 100 years old and considered antique.