Maryland Courts and Judicial Proceedings Section 3-208
§ 3-208.
  (a)   If a party denies existence of the arbitration agreement, he may petition a court to stay commenced or threatened arbitration proceedings.
  (b)   (1)   A petition to stay arbitration shall be filed with the court where a petition to order arbitration has been filed.
    (2)   If a petition for order to arbitrate has not been filed, the petition to stay arbitration may be filed in any court subject to venue provisions of Title 6 of this article.
  (c)   If the court determines that existence of the arbitration agreement is in substantial and bona fide dispute, it shall try this issue promptly and order a stay if it finds for the petitioner. If the court finds for the adverse party, it shall order the parties to proceed with arbitration.