550 U.S. 544 (2007) Cited 276,716 times 369 Legal Analyses
Holding that allegations of conduct that are merely consistent with wrongdoing do not state a claim unless "placed in a context that raises a suggestion of" such wrongdoing
457 U.S. 147 (1982) Cited 5,768 times 33 Legal Analyses
Holding that named plaintiff must prove “much more than the validity of his own claim”; the individual plaintiff must show that “the individual's claim and the class claims will share common questions of law or fact and that the individual's claim will be typical of the class claims,” explicitly referencing the “commonality” and “typicality” requirements of Rule 23
472 U.S. 797 (1985) Cited 1,814 times 19 Legal Analyses
Holding that “the Due Process Clause of course requires that the named plaintiff at all times adequately represent the interests of the absent class members”
Holding plaintiffs' failure to provide information regarding sales made by insiders at times outside the class period permitted no possibility of comparison
Holding that the particularity requirement applies not only to actual fraud claims but also to "associated claims where the core allegations effectively charge fraud"
Holding that intervenor who opposed consent decree could not appeal the district court's order approving the decree without satisfying Article III standing requirements
Fed. R. Civ. P. 23 Cited 35,874 times 1249 Legal Analyses
Holding that, to certify a class, the court must find that "questions of law or fact common to class members predominate over any questions affecting only individual members"
Mass. Gen. Laws ch. 93A § 9 Cited 912 times 10 Legal Analyses
Requiring on its face that the "written demand" must "reasonably describ[e] the unfair or deceptive act or practice relied upon and the injury suffered"
Mass. Gen. Laws ch. 266 § 91 Cited 35 times 1 Legal Analyses
Prohibiting "untrue, deceptive or misleading" statements of fact in "an advertisement of any sort regarding merchandise, securities, service or anything so offered to the public"