Steve Didmon v. American Arbitration Association, Inc. and Frontier Drilling USA, Inc. N/K/A Paragon Offshore USA Inc., 01-16-00022-CV

Didmon sued Frontier and related entities for personal injuries from an offshore rig accident; defendants removed under the New York Convention but federal court remanded after finding one arbitration agreement unenforceable for lack of a Frontier signatory.
On remand, a second arbitration clause (in Didmon’s employment agreement) required arbitration in Singapore; this court later reversed a trial-court denial of arbitration and remanded.
The trial court dismissed Didmon’s suit without prejudice and allowed the defendants to raise limitations if Didmon did not initiate arbitration; Didmon later initiated arbitration in Singapore but did not name Frontier there.
Didmon then demanded arbitration with the American Arbitration Association (AAA) naming Frontier and relying on the previously-invalidated agreement; the AAA administratively refused the demand.
Didmon sued AAA to compel appointment of an arbitrator; Frontier intervened, asserting collateral estoppel (from the federal court ruling) and limitations defenses; the trial court denied Didmon’s motion to strike the intervention and later granted summary judgment to both Frontier and AAA.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether Frontier had a justiciable interest to intervene	Didmon: Frontier lacks interest because suit seeks relief only against AAA to appoint an arbitrator	Frontier: A Didmon victory would force Frontier to defend arbitration; collateral estoppel and limitations bar arbitration	Court: Frontier has a justiciable interest; denial of motion to strike affirmed
Whether AAA is immune from suit for refusing to appoint an arbitrator	Didmon: AAA violated its rules and an arbitrator must decide enforceability/jurisdiction	AAA: Arbitral immunity bars suit against AAA	Court: Summary judgment for AAA vacated as moot after Frontier judgment; underlying arbitral immunity ruling not reached on appeal because Frontier judgment mooted the dispute
Effect of Frontier’s summary judgment defenses on Didmon’s claims	Didmon: Defenses should be left to arbitrator	Frontier: Collateral estoppel and statute of limitations preclude arbitration	Court: Frontier’s unchallenged summary judgment resolving arbitrability moots Didmon’s AAA claim
Whether judgment against AAA remains after Frontier’s judgment	Didmon: Seeks relief compelling AAA regardless of Frontier’s defenses	Frontier/AAA: Frontier’s judgment eliminates any live controversy	Court: Vacated AAA judgment and dismissed Didmon’s suit against AAA as moot

In re Union Carbide Corp., 273 S.W.3d 152 (Tex. 2008) (justiciable interest required for intervention)
Guar. Fed. Sav. Bank v. Horseshoe Operating Co., 793 S.W.2d 652 (Tex. 1990) (intervenor has justiciable interest if it could have filed suit or defeat recovery)
Zeifman v. Michels, 229 S.W.3d 460 (Tex. App.—Austin 2007) (judgment for plaintiff that may lead to action against intervenor supports intervention)
Evan’s World Travel v. Adams, 978 S.W.2d 225 (Tex. App.—Texarkana 1998) (same principle regarding intervention)
Nall v. Plunkett, 404 S.W.3d 552 (Tex. 2013) (when procedural challenge fails on appeal, affirm otherwise unchallenged summary judgment)
Heckman v. Williamson Cty., 369 S.W.3d 137 (Tex. 2012) (justiciability and mootness principles govern appeals)
Williams v. Lara, 52 S.W.3d 171 (Tex. 2001) (justiciability requirement)
Houston Mun. Emps. Pension Sys. v. Ferrell, 248 S.W.3d 151 (Tex. 2007) (vacating judgment as to one party and dismissing mooted claims)