Is First Interstate BancSystem (FIBK) A Smart Long-Term Buy? Diamond Hill Capital, an investment management firm, published its “Diamond Hill Small Cap Fund” first quarter 2021 investor letter – a copy of which can be downloaded here. The portfolio outpaced the Russell 2000® Index in the quarter with positive absolute results across all sectors. You can view the fund’s top 5 holdings to have a peek at their top bets for 2021. Diamond Hill Capital, in its Q1 2021 investor letter, mentioned First Interstate BancSystem, Inc. (NASDAQ: FIBK), and shared their insights on the company. First Interstate BancSystem, Inc. is a Billings, Montana-based bank holding company that currently has a $2.8 billion market capitalization. Since the beginning of the year, FIBK delivered a 13.56% return, extending its 12-month gains to 57.64%. As of May 21, 2021, the stock closed at $46.30 per share.