On March 27, 2013, the U.S. Supreme Court ruled in favor of Comcast Corp. in an antitrust class action suit regarding so-called “clustering”— the practice of expanding the geographically contiguous service area of a cable operator by acquiring adjacent cable systems and/or swapping cable systems with other operators. Plaintiffs alleged that Comcast’s clustering in and around Philadelphia resulted in harm to a large class of Comcast customers. Plaintiffs’ economic experts advanced four theories of harm from Comcast’s clustering. However, the U.S. District Court for the Eastern District of Pennsylvania certified a class only with regard to one theory of harm put forth by plaintiffs—the alleged reduction in potential competition from cable “overbuilders,” ruling that the other theories of harm could not be assessed on a class-wide basis. The U.S. Supreme Court overturned the class certification of the lower court on the one remaining theory of harm, ruling that since the damage model offered by plaintiffs’ expert did not isolate alleged damages attributable to each individual theory of harm, plaintiffs failed to show that the appropriate measure of damages pursuant to the one remaining theory could be determined on a class-wide basis. Comcast was assisted by a Compass Lexecon team in the Century City office which included Andres Lerner, Emmett Dacey and Janin Wimer. The team supported an outside expert in submitting multiple reports and providing deposition and hearing testimony regarding both liability and class certification issues, and worked closely with counsel for Comcast, including Sheron Korpus of Kasowitz, Benson, Torres & Friedman. In addition, Compass Lexecon experts Jon Orszag and Bobby Willig submitted written testimony, and Orszag provided deposition testimony, regarding their prior econometric analyses of Comcast’s pricing in the Philadelphia area.