Every manufacturer has Stop Start and Fill buttons too. There's no patent on how you make double duty of arranger buttons. Doesn't seem like there's much in the way of any patents at all, as Korg lifted the Chord Sequencer from Roland, or the way that multi-pad ideas spread...

And no-one has ASKED me to help with arranger design. Be happy to if asked!
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An arranger is just a tool. What matters is what you build with it..!