IDAHO INDEPENDENT BANK SHAREHOLDER ALERT: Rigrodsky & Long, P.A. Announces Investigation of Merger

Rigrodsky & Long, P.A. announces that it is investigating potential legal claims against the board of directors of Idaho Independent Bank (“IIBK” or the “Company”) (OTC PINK: IIBK) regarding possible breaches of fiduciary duties and other violations of law related to the Company’s entry into an agreement to merge with First Interstate BancSystem, Inc. (“First Interstate”) (NASDAQ GS: FIBK) in a transaction valued at approximately $181.3 million. Under the terms of the agreement, shareholders of IIBK will receive 0.5 shares of First Interstate common stock for each share of IIBK common stock.