Mont. Code Ann. § 32-1-604

Whenever any banking institution shall have been closed as aforesaid and said federal deposit insurance corporation shall pay or make available for payment the insured deposit liabilities of such closed institution, said corporation, whether or not it shall have been appointed agent of the department in the liquidation of such closed banking institution, as herein provided, shall be and become subrogated by operation of law to all rights against such closed banking institution of each owner of a claim for deposit to the extent now or hereafter necessary to enable the federal deposit insurance corporation, under federal law, to make insurance payments available to depositors of closed insured banks.