The Tenth Circuit has ruled that Microsoft didn't kill WordPerfect. The market did.

Or at least that, if Microsoft did commit software-icide, it didn't lose money doing it and therefore Did Nothing Wrong. Novell, Inc. v. Microsoft Corp., No. 12-4143 (10th Cir. Sept. 23, 2013).

For other instances of antitrust-icide in the Tenth Circuit, see here and here.