The legality of Shuriken: shuriken have been popularized in movies as a weapon of Ninjutsu. There are many different types of shuriken. There are many websites and martial art stores that sell shuriken and there are videos that show how you can make your own. It is very important to know the laws where you live. In some areas it is a crime for a person to make, import, sell, give or possess a shuriken. In some areas, you can possess them at home, but can you carry it or carry it as a concealed weapon? The risk of spending lots of money on a criminal defense lawyer outweighs any benefit. Any ninja fantasies you have about using them will fade rapidly if you ever use them or do prison time to their use.
Shuriken are prohibited in some countries, such as Belgium, the Netherlands, Canada, Germany, and the United Kingdom. In the USA, some states explicitly prohibit them; Cilifornia, Indiana, New York. Other states could prosecute based on the use in a crime, or as a concealed weapon or if used for self-defense which caused excessive injury.