Mont. Code Ann. § 76-15-214

In a suit, action, or proceeding involving the validity or enforcement of or relating to a contract, proceeding, or action of the district, the district shall be considered to have been established in accordance with this chapter upon proof of the issuance of the certificate by the secretary of state. A copy of the certificate, duly certified by the secretary of state, is admissible in evidence in the suit, action, or proceeding and is proof of the filing and contents thereof.