The trial court correctly denied Mattson’s motion to compel arbitration of Applied’s suit against it for violation of the Uniform Trade Secrets Act. Mattson had hired Lai away from Applied.  Lai’s employment agreement with Applied contained an arbitration clause.  Mattson was not a party to that contract and could not enforce it on a equitable estoppel basis since Applied’s claim against Mattson was based on the Uniform Trade Secrets Act, not Lai’s employment agreement.  (See Waymo LLC v. Uber Techs., Inc. (Fed. Cir. 2017) 870 F.3d 1342.)  However, the trial court erred in not staying the court litigation of the claim against Mattson pending the arbitration of Applied’s claims against Lai, which the trial court had properly compelled under his employment agreement.  Under CCP 1281.4, a court must stay litigation if there is even a single overlapping question of law or fact between the court litigation and the arbitration.