3M Prints temporary logos on all window film products for "Authenticity".  We make an effort to remove them at the time of installation, but sometimes they get missed or they we cannot access the area while the film is curing.  They can be removed with a liberal amount of Rubbing Alcohol (like you find in your first aid kit or bathroom) and a paper towel - wet the towel, rub in circles for 10 seconds, the logo will disappear.  You are always welcome to stop back at the shop and we can remove them