Have you contacted them to see what's up? At the very least, you might be able to get them to give you some credit on the design idea...
But with what you are describing, that is how styles were developed in the past. Some mad man came up with a new way of doing things, and other copied. Before you know it, you got a new style.
I guess what I am saying, I don't see a whole lot of problem with them using your idea, so long as they are willing to give you credit for it and not outright lie and say it's their own. In fact, perhaps you should be honored that others got inspiration from your ideas.
Personally, I have shared my ideas regarding things like infill and enclosure in the hope that someone else will get inspiration from it, and use these ideas. My aim is to better the industry, not to make a million bucks for myself and hoard my 'intellectual property' (a 100% modern idea)
sorry for the ramble, I do that some times!
DLB
