Just out of curiousity (I really don't know) - how did Microsoft adopt the mouse? Same was as Apple? Or just taking it? Or through licensing from Xerox?
I believe they basically licensed the patent, but I'm not sure.
Basically, Apple didn't have any of that stuff patented because it wasn't theirs to patent. I'm sure Xerox didn't giva a damn who used it, and I'm not sure they even invented the mouse.
There's a long history for this stuff. The mouse and basic idea for the GUI was invented in the 60s, and eventually some of those people went to work at Xerox, where they refined the idea and got a rudimentary mouse-based GUI working. Later, some Xerox engineers went to work at Apple, who took the idea to the next step, actually making it usable and commercially viable.