As far as I know there was one main patent -- 6,988,138 -- which was utter garbage and was invalidated in 2009.
It was this patent which BlackBoard used to try to shut down a competitor named Desire2Learn in 2006. The invalidation forced Blackboard to retreat, and they've since been much quieter on the legal front.
It was this patent which BlackBoard used to try to shut down a competitor named Desire2Learn in 2006. The invalidation forced Blackboard to retreat, and they've since been much quieter on the legal front.