Apple used code for a project called WINE which is a compatibility layer that allows Windows games and applications to run on Linux. Apple used this to make their new Game Porting Toolkit to allow Windows games to run on IOS/OSX. Since WINE is free and open-source software, Apple can freely use the code. WINE survives on donations, apple did not donate, despite profiting off of and using a huge chunk of the WINE codebase.