Richard A. Williamson [NPE] filed suit against Blackboard over a patent related to distance-learning applications.  The complaint is currently unavailable.  Williamson has filed three prior suits since November 2002 against more than 20 defendants, including Adobe, AT&T, Cisco, Citrix, IBM, Microsoft, Salesforce.com, and Verizon.  Blackboard  filed an action for declaratory judgment against Williamson and At Home Bondholders’ Liquidating Trust on May 20, 2012.  The patent-in-suit originated with At Home Corporation, and At Home Bondholders’ Liquidating Trust is listed as the current assignee according to the PTO.  Regarding an earlier suit against AT&T and Verizon, Bloomberg reported that Williamson is the trustee for At Home.  5/18, Central District of California, Judge John A. Kronstadt, 2:2012cv04335.