This is interesting. I draw your attention to Williams v. U.S. Bancorp Investments, Inc. (June 8, 2020), in which the Court of Appeal (First Appellate District, Division Four) concluded that collateral estoppel does not bar an absent member in a putative class that was initially certified, but later decertified, from subsequently pursuing an identical class action. The Court held that the reasoning of Smith v. Bayer Corp., 564 U.S. 299, 312–316 (2011) and Bridgeford v. Pacific Health Corp., 202 Cal. App. 4th 1034, 1041–1044 (2012) applied equally to this variation.