Quote Originally Posted by doom_Oo7 View Post
Wouldn't have happened (legally) with GPL
Actually it would have happened in exactly the same way.

Apple release the source code to their XNU kernel - but porting it to FreeBSD isn't as easy as you think. Though the two share a lot of code, the entire lower half and driver model of Apple's XNU is different to FreeBSD. It's not some copy and paste job.

In re porting from Linux: The DRI stack is BSD licensed; this was agreed back in the XFree86 days as a means of allowing Linux, the BSDs, and Solaris to combine their efforts in driver support.