Whether courts may presume parties intended to let an arbitrator decide if class arbitration is available when they 'simply agree[d] to submit' disputes over arbitrability 'to an arbitrator?

QUESTION PRESENTED The circuit courts of appeal have split 3-3 on what contractual language is necessary before an arbitrator, instead of a court, can decide whether class-action arbitration is available (“class arbitrability”). In Stolt-Nielsen, S.A. v. AnimalFeeds Int'l Corp., this Court held that for class action arbitration to proceed there must be a “contractual basis” for concluding the parties “agreed to” it. 559 U.S. 662, 684 (2010). Courts could not “presume” such consent “from the fact of the parties’ agreement to arbitrate” because “the parties’ intentions control” the interpretation of arbitration agreements, and “class-action arbitration changes the nature of arbitration to such a degree that it cannot be presumed the parties consented to it by simply agreeing to submit their disputes to an arbitrator.” Id. at 682, 685, 687. In other words, parties employing standard arbitration language were presumed not to have intended to say anything about class-action arbitration. Jd. at 686. The question presented asks whether this same presumption applies to agreements to arbitrate questions of arbitrability. Specifically: May courts presume parties intended to let an arbitrator decide if class arbitration is available when they “simply agree[d] to submit” disputes over arbitrability “to an arbitrator?” 1. This Petition also presents the Court with the ability to either (i) assume, without deciding, that the availability of class arbitration is a question of arbitrability, or to (ii) decide an issue “this Court has not yet decided,” i.e., “whether the availability of class arbitration is a question of arbitrability.” Oxford Health Plans LLC v. Sutter, 569 U.S. 564, 569-70 n.2 (2018).