> For something to be a blatant copy I'd expect when shown both samples of work, one could imagine how multiple people would have come up with the same end result based on the same inspiration, no innovation or invention of their own put into the process. When I look at the Casio products, sure, the general inspiration definitely could have come from those, but it's hard to see how one could honestly claim TE have not invested any innovation or invention of their own when coming up with their products even if inspired by Casio. "Blatant copy" is an incredible stretch.

Some of these devices are popular and more than 30 year old. And these are not Teenage Engineering's...

Of course TE copied Casiotone series and of course TE designers knows very well they exist.

Old Casiotone synth designs are absolutely unique in the history of synth industry.