because the dismissal of the signatory defendants in that case was part of a scheme, clearly designed to bypass an arbitration agreement’s effect, that joined them and the formerly adverse plaintiff as joint plaintiffs in a new suit against the non-signatory defendants. See id. at 526, 528, 530. Equity would not allow such scheming to avoid arbitration. See id. at 528. Moreover, the non-signatory defendants had obviously answered. See id., passim. The record here, in contrast, shows only that Sullivan and Havard had not yet answered or been served, not that they were served, only to be dismissed later pursuant to a scheme akin to that in Grigson. McMillan, on which the Auto Nation parties also rely, is distinguishable for similar reasons. See id., 66 S.W.3d at 479, 481, 483 (<HOLDING>). We hold the Auto Nation parties did not carry
holding nonsignatory defendant companies affiliated with signatory defendant company could enforce arbitration agreement against signatory plaintiff when same operative facts were involved holding trial court must decide whether to compel arbitration of personal injury claim of party who was not signatory to arbitration agreement holding nonsignatory defendants who were sued separately from signatory defendants on same claims could enforce arbitration agreement under this equitable exception further nonsignatory defendants were undisputedly agents or servants of signatory defendants holding that nonsignatory was estopped from denying applicability of arbitration clause where nonsignatory received direct benefits from contract including lowered insurance rates and the ability to sail under the french flag holding that an exception to the rule that a nonsignatory cannot invoke arbitration exists when under agency or related principals the relationship between the nonsignatory and a signatory is sufficiently close that the only way to avoid eviscerating the arbitration agreement is to allow the nonsignatory to compel arbitration