In the 2012 case of Amgen Inc. v. Connecticut Retirement Plans and Trust Funds, the U.S. Supreme Court ruled in favor of Connecticut Retirement Plans and Trust Funds (Connecticut). The case revolved around a securities fraud class action lawsuit filed by Connecticut against biotech company Amgen Inc., alleging that they had made misrepresentations about two of their flagship drugs which inflated their stock price, causing significant losses to investors when the truth was revealed. The key issue before the court was whether plaintiffs needed to prove materiality - that is, whether an average investor would have considered these misrepresentations important - at the class certification stage itself or could it be deferred until trial? In a 6-3 decision, Justice Ginsburg writing for majority held that proof of materiality wasn't necessary at this early stage as it's a merits-based issue meant for trial; rather only plausibility suffices i.e., if such alleged deceitful conduct could reasonably have swayed investors' decisions.

In the dissenting opinion for the AMGEN INC., et al., v. CONNECTICUT RETIREMENT PLANS AND TRUST FUNDS case, Justice Scalia, joined by Justice Thomas and partially by Justice Kennedy, argued that materiality should be proven before class certification. He contended that Rule 23(b)(3) requires a court to find that questions of law or fact common to class members predominate over any questions affecting only individual members. The majority's view was seen as inconsistent with this rule because it allowed certification without proving materiality - an element of the claim which would inevitably require individualized proof if not established at the outset. Thus, in his view, failure to prove materiality up front could lead to a situation where individual issues end up predominating over common ones later on in litigation – contrary to what Rule 23(b)(3) demands.