Mont. Code Ann. § 35-15-402

Forfeiture of the stock for nonpayment of installments may be provided for in the bylaws, and whenever a share of stock is forfeited, such share shall become the property of the association and may be reissued to any person already a holder of common stock; but any proceeds received by the association from such reissue, over and above the amount due on said share, shall be paid to the delinquent shareholder.