On May 18, 2009, in In re Tobacco II Cases, No. S147345 (“Tobacco”), the California Supreme Court answered two questions raised by Proposition 64, a November 2004 voter initiative that amended California’s Unfair Competition Law (“UCL”): Who in a UCL class action must comply with Proposition 64’s standing requirements – just the representative plaintiff, or all putative class members – in order for the class action to proceed, and what is the causation requirement for the purpose of establishing standing under the UCL?