Sears, Roebuck and Co. v. Butler

(1) Whether Federal Rule of Civil Procedure 23(b)(3)'s predominance requirement for class action certification can be satisfied based solely on a determination that it would be "efficient" to decide a single common question at trial, without considering any of the individual issues that would also need to be tried, and without determining whether the aggregate of common issues predominates over the aggregate of individual issues; and (2) whether a class may be certified on breach of warranty claims where it is undisputed that most members did not experience the alleged product defect and where fact of injury would have to be litigated on a member-by-member basis.