Now you'll put me in a rambling mood....
Yeah, I had to deal with eh Yamaha FM patent in the early '90s at the computer company I was working for, they had it locked up so tightly we had to go in a different direction, and fortunately that direction paid off, we did better than we could have had we licensed theirs.
And thinking about this made me miss Ensoniq again. Their chip in the Apple IIgs was a pretty awesome thing to work with in the mid-80's, the programming model fit my brain really well.
And... ah, I'm not going to ramble more tonight, I could have a problem stopping. Have a digital delay module out in the workshop I have to finish up tonight so I'll go do that.