317 institutions reported holding $3.56B of FIRST INTST BANCSYSTEM INC (FIBK) in SEC 13F filings for 2026-06-30. Largest institutional holders: BlackRock, Inc. ($529.5M), VANGUARD GROUP INC ($383.7M), STATE STREET CORP ($241.0M), DIMENSIONAL FUND ADVISORS LP ($223.0M), First Interstate Bank ($177.9M). Source: SEC Form 13F.
Source: SEC Form 13F filings · as of 2026-06-30