yep and the trash can - apple vs. microsofthttps://en.wikipedia.org/wiki/Apple_Com ... osoft_Corp
Its more straight forward when someone copies a graphic it seems, over code. the whole source code copying is still very much evolving as some source code copying can be fair use - e.g. androids copying of Java APIs
The apple vs MS argument was both patent and copyright, as they originally tried to patent the GUI, and then tried to copyright the desktop concept (effectively windows), they failed, but they were successful in protecting the icons and images used.
If you look at Linux Mint for example - you can see it picks the best of the mac and windows world nicely.