This is an unfortunate misconception. Some of Apple's significant BSD/MIT/Apache contributions, off the top of my head: * LLVM and clang (MIT) - http://llvm.or

This is an unfortunate misconception. Some of Apple's significant BSD/MIT/Apache contributions, off the top of my head: * LLVM and clang (MIT) - http://llvm.org/ http://llvm.org/ * libdispatch, aka GCD (Apache) - http://libdispatch.macosforge.org/ http://libdispatch.macosforge.org/ * launchd (Apache) - http://launchd.macosforge.org/ http://launchd.macosforge.org/ * OpenBSM (BSD) - http://www.trustedbsd.org/openbsm.html http://www.trustedbsd.org/openbsm.html * mDNSResponder (Apache/BSD) - http://developer.apple.com/opensource/internet/bonjour.html http://developer.apple.com/opensource/internet/bonjour.html Nearly all the code to the base system is available under the non-BSD APSL, but the fact is that most of it just isn't useful to the BSDs, and if it were, Apple would likely be open to contributing the code under an alternative license (eg, they re-licensed launchd under the Apache license): http://www.opensource.apple.com/release/mac-os-x-1062/ http://www.opensource.apple.com/release/mac-os-x-1062/