IfI understand patent rules correctly as they were explained to me by a friend of mine.

If a company has a patent on a product a person can buy or copy that patent after a certain number of years. However, if it's patent pending then you can't copy the design.

So, never fully patent a product and you will not have to worry about someone copying it or improving on the design. Always leave it patent pending like you are still in the developmental stage. Check out the products that no one else has copied and you'll find that they are all patent pending.

Bottom line is that if the STS is patented someone can copy the design and there is no legal recourse. If they've never patented it then they are SOL. Again, that's how it was explained to me.