Failure to include the 'CE' icon means the product wasn't manufactured by Prada's factory (Luxottica) and is surely a fake. All Prada sunglasses are manufactured in Italy by Luxottica. Should include the Prada logo, a ‘Made in Italy’, and the ‘CE’ icon, which means the product conforms with European regulations.
Betcha never seen anything like this before! Here's the tips, tricks and secrets of how to authenticate Prada sunglasses.