X0206 3 2022-02-01 0 0000860413 FIRST INTERSTATE BANCSYSTEM INC FIBK 0001198518 HEYNEMAN JOHN M JR P.O. BOX 7113, BILLINGS MT 59103 1 0 1 0 0001908784 Riki Rae Scott Davidson & John Heyneman Jr., Trustees FBO Riki Scott Davidson Exemption Trust Under the Scott Family 1996 Trust P.O. BOX 7113, BILLINGS MT 59103 0 0 1 0 0001908849 Rae Ann Morss & John Heyneman Jr., Trustees FBO Rae Ann Morss Exemption Trust Under the Scott Family 1996 Trust P.O. BOX 7113, BILLINGS MT 59103 0 0 1 0 0001908848 John M Heyneman Jr. Trust 4100 BIG HORN AVE, SHERIDAN WY 82801 0 0 1 0 0001908810 Towanda Investments Limited Partnership 4100 BIG HORN AVE, SHERIDAN WY 82801 0 0 1 0 Class A Common Stock 6814 D Class B Common Stock 0.00 Class A Common Stock 1412385 I See footnote As a result of certain agreements entered into by and among the reporting persons, the Issuer, and certain other stockholders of the Issuer, the reporting persons may be deemed members of a group with the other signatories thereto and may be deemed to share beneficial ownership of the securities reported herein. Each of the reporting persons disclaims beneficial ownership of any such securities, except to the extent of its pecuniary interest therein. The reporting persons expect to file future Forms 4, if any, together with John M. Heyneman, Jr. The Class B Common Stock is convertible at any time into Class A Common Stock on a share for share basis at the discretion of the holder. The conversion feature of the Class B Common Stock does not expire. Composed of 139,921 shares held of record by John M Heyneman Jr. Trust, 15,000 shares held of record by John M Heyneman Jr., 85,836 shares held of record by Riki Rae Scott Davidson & John Heyneman Jr., Trustees FBO Riki Scott Davidson Exemption Trust Under the Scott Family 1996 Trust, 85,836 shares held of record by Rae Ann Morss & John Heyneman Jr., Trustees FBO Rae Ann Morss Exemption Trust Under the Scott Family 1996 Trust, and 1,085,792 shares held of record by Towanda Investments Limited Partnership. Exhibit 24 - Power of Attorney JOHN M. HEYNEMAN, JR., By: /s/ Timothy Leuthold, Attorney-in-Fact for Reporting Person 2022-02-10 JOHN M HEYNEMAN JR. TRUST, By: /s/ Timothy Leuthold, Attorney-in-Fact for Reporting Person 2022-02-10 RIKI RAE SCOTT DAVIDSON & JOHN HEYNEMAN JR., TRUSTEES FBO RIKI SCOTT DAVIDSON EXEMPTION TRUST UNDER THE SCOTT FAMILY 1996 TRUST, By: /s/ Timothy Leuthold, Attorney-in-Fact for Reporting Person 2022-02-10 RAE ANN MORSS & JOHN HEYNEMAN JR., TRUSTEES FBO RAE ANN MORSS EXEMPTION TRUST UNDER THE SCOTT FAMILY 1996 TRUST, By: /s/ Timothy Leuthold, Attorney-in-Fact for Reporting Person 2022-02-10 TOWANDA INVESTMENTS LIMITED PARTNERSHIP, By: /s/ Timothy Leuthold, Attorney-in-Fact for Reporting Person 2022-02-10