A trivial example would be a commit that shows something was implemented and then later removed because of a patent/IP violation. 1-jan-2003 - bob: added n

A trivial example would be a commit that shows something was implemented and then later removed because of a patent/IP violation. 1-jan-2003 - bob: added new feature X 5-jan-2003 - bob: Rev 1.0 8-oct-2012 - frank: Turns our X was patented in 2001 but we didn't realize it. Replace feature X with something that doesn't violate patent ######