In 2006, Klausner presided over "United States v. Ancheta", the federal prosecution of Jeanson James Ancheta of Downey, California, the first botnet-related prosecution in U.S history. Following Ancheta's guilty plea, Klausner sentenced Ancheta to 57 months in prison for various botnet-related crimes. In 2016, Klausner presided over a copyright case filed by the estate of Spirit guitarist Randy Wolfe against Led Zeppelin founders Robert Plant and Jimmy Page. The estate of Wolfe alleged that Wolfe was entitled to a writing credit for the song "Stairway to Heaven"; Klausner ruled in April 2016 that a jury could find "substantial similarity" between the elements of the two songs. In another copyright case arising from the "Star Trek" fan film "Prelude to Axanar", Klausner rejected various motions by both parties in January 2017, setting the stage for a civil trial on the matter to go forward. The parties settled the suit. In August 2017, Klausner dismissed a class-action lawsuit filed by boxing fans who contended that the 2015 Floyd Mayweather Jr. vs. Manny Pacquiao boxing match was deceptively marketed because Pacquiao failed to disclose a shoulder injury that affected his performance. Klausner ruled that fans of sporting events have no right to have the event meet their expectations for excitement. In October 2017, Klausner ruled in favor of the plaintiff Coachella Music Festival in a lawsuit against the fledgling "Filmchella" film festival, finding that the names were likely to cause consumer confusion.