That patent is on NeXTSTEP's NSDistributedNotificationCenter [1], which admittedly might actually be enforceable (I'm not sure of any prior art in this regard).

That patent is on NeXTSTEP's NSDistributedNotificationCenter [1], which admittedly might actually be enforceable (I'm not sure of any prior art in this regard). That said, after reading the claims of a lot of the other patents Apple is citing it is apparent that they are complete rubbish, for example [2] (the observer pattern applied to a desktop environment), [3] (generic proxy objects for IPC/RPC - Smalltalk/CORBA did it), and [4] (WTF???????). 1. http://developer.apple.com/mac/library/documentation/Cocoa/Conceptual/Notifications/Articles/NotificationCenters.html#//apple_ref/doc/uid/20000216 http://developer.apple.com/mac/library/documentation/Cocoa/C... 2. http://www.google.com/patents/about?id=zIwLAAAAEBAJ http://www.google.com/patents/about?id=zIwLAAAAEBAJ 3. http://www.google.com/patents/about?id=7d4aAAAAEBAJ http://www.google.com/patents/about?id=7d4aAAAAEBAJ 4. http://www.google.com/patents/about?id=HrobAAAAEBAJ http://www.google.com/patents/about?id=HrobAAAAEBAJ