All About Pocket Knives

I have a switchblade I've had for years old but how old I don't know. It's marked uppercase B over Rostfrei. I was on the website Stiletto-italiano.com reading about the Beltrame knives. According to this website the Beltrame family says that a knife marked in this fashion is a fake. But if it's marked with a lower case b it's right. Everyone welcome to put there two cents in and give there opinion. Do I more than likely have a fake or not? Thanks, Jason.