Originally posted by Lee
I think the wankle was originally designed in Germany. When they gave up the Japanese bought the right to produce it.
This is all from memory but it was invented by Felix Wankel (from Germany?) who sold the rights to NSU who used it in their Ro80. After NSU stopped making them the rights were sold to Mazda. The rights to make small Wankel engines went to Graupner (I'm not sure what the upper limit for size was though) who were then approached by OS.