LOL, we are all saying the same thing using different words!

A Non Recurring Engineering Fee, in simplest terms, is a one time payment made to modify an existing item to fit the specific needs of a particular application.

There would be no room for an exclusivity clause with something as disruptive as this interposer seems to be, because the owner would simply say "no, sorry, won't do that" and call the  number of the next customer in the line.  :-)

IMO, of course