After trial, the defendants argued, among other things, that the plaintiffs “did not meet the ‘predominance of common questions’ requirement of Rule 23(b)(3) because damages could not be calculated on a class-wide basis.” Rejecting this argument, the U.S. Sixth Circuit Court of Appeals noted that “Columbia erroneously assumes that the issue of damages must predominate. To the contrary, ‘predominance is a test readily met in certain cases alleging violations of the antitrust laws,’ because proof of the conspiracy is a common question that is thought to predominate over the other issues of the case. Indeed, we have never required a precise mathematical calculation of damages before deeming a class worthy of certification. Here, the district court found that the ‘allegations of price-fixing and market allocation … will not vary among class members.’ Accordingly, the court found that the ‘fact of damages’ was a question common to the class even if the amount of damages sustained by each individual class member varied. We, therefore, find no error in the district court’s analysis.” See In re Scrap Metal Antitrust Litigation, 527 F.3d 517 (6th Cir. 2008).