Blackboard (WebCT owner), Desire2Learn End Dispute

Blackboard and Desire2Learn have formally ended their three-and-a-half-year legal dispute, a conflict that was triggered when Blackboard received a hotly disputed patent for electronic learning technologies and proceeded to enforce it through litigation against D2L.

http://thejournal.com/articles/2009/12/15/blackboard-desire2learn-end-dispute.aspx