Split Cycle 4 Stroke???

[Mouse]

I was reading some old posts here on the board and came across a post about a company who had built a new variation of the split cycle 4 stroke engine. (The company got sued (2012) by HINO who alleged it was a Pozi sceme.)
Having never heard of a split cycle four stroke engine, I googled it. Now that I've read up on it and seen some animations of it, can someone with more smarts than me please explain the difference between a supercharged 2 stroke and a split cycle 4 stroke.