"I don't understand why this guy should be grateful." I wasn't asserting that he should, Tyng was. And I don't want to get into a debate on the validity of sof

"I don't understand why this guy should be grateful." I wasn't asserting that he should, Tyng was. And I don't want to get into a debate on the validity of software patents, because I'm still undecided on the matter. Tyng stated that Apple improved on Gelernter's idea, and I don't think anyone will disagree with that. You compared the situation to Google and Microsoft copying Apple's ideas. I'm saying that isn't a fair comparison, because there is no consensus on whether Android is significantly better than iOS and whether Windows is significantly better than Mac OS. "Apple was not grateful [for the creation of Windows and Android] so why should this guy be grateful." I very much doubt that Apple saw the initial versions of Windows and Android as major improvements over their own OSes. Imitation can be the sincerest form of flattery, but doing it badly is simply insulting. I think it's hard to tell what Apple would do if some company took Apple's ideas and made significant improvements to them, since I can't recall such an event ever happening. Well, maybe one: the Palm Pilot versus the Newton MessagePad. And I don't think Apple sued USRobotics over it.