Stephen Downes’s misnamed A Patent Dilemma (because there is no dilemma) on why patenting some core aspects of an online learning environment and then taking legal action against another company is a really wrong thing for Blackboard to have done (sign up for free full-text access):
http://www.innovateonline.info/index.php?view=article&id=399, Downes, S. 2006. A Patent dilemma. Innovate 3 (2).
Includes an introduction to the ineptitude of the US Patent Office, and responses from various e-learning blog-notables. Significantly, Innovate gave Blackboard the opportunity to respond with a counterpoint article – they declined. Because there is no defence.