Listening to oral argument recordings from various cases presents an opportunity to try and read the tea leaves as to where the Federal Circuit is heading with respect to a particular area of the law. The oral argument in Walker Digital v. Microsoft, 2011-1419 (Fed. Cir. 2012) presents one such opportunity.
In the oral argument of Walker Digital v. Microsoft, which was argued on March 9, 2012, Judge Moore made a comment about the patentee having a problem if the claims were construed in such a way that they required joint infringement. The Akamai v. Limelight and McKesson v. Epic cases were argued en banc four months earlier — so, presumably, Judge Moore knew as of March 9, 2012 which way the CAFC was headed in deciding those cases when she made her comment. You can listen to the sound bite yourself and see if you think it indicates how the CAFC will decide those en banc divided infringement cases: [Listen].
As a sidenote, Judge Moore also took a friendly shot at patent prosecutors and their alleged deficiencies when it comes to knowing the rules of grammar: [Listen]. Ouch. Of course, a patent prosecutor is entitled to be his or her own grammarian. See Chicago Steel Foundry Co. v. Burnside Steel Foundry Co., 132 F.2d 812, 814-15 (7th Cir. 1943), cited in Jonsson v. Stanley Works, 903 F.2d 812, 820-21 (Fed. Cir. 1990).