Mont. Code Ann. § 50-53-214

Upon cancellation of a license or the right to operate one or more public swimming pools under a single license for the premises, the operator of the public swimming pool shall return the license to the department for destruction of the license or deletion of the listing of the public swimming pool affected by the cancellation. Cancellation by the department of a license to operate a public swimming pool is effective notwithstanding the refusal or failure of an operator to return the license to the department.