A Delaware district judge invalidated claims of two Walker Digital patents, ruling those asserted against Google and eight other companies are invalid due to lack of patentable subject matter. Wednesday’s decision stems from a suit filed by Walker Digital in 2011 against nine defendants including Facebook, Friendster, Google, LinkedIn, Myspace, News Corp., and Tagged. Walker Digital accused defendants’ social networking products of infringing two of its patents related to anonymous communication (5,884,270, 5,884,272). As of June 2013, all the defendants except Google had exited the case and, according to court documents, had signed license agreements with Walker Digital.