FIRST INTERSTATE BANCSYSTEM INC — Director's Dealing 2015

May 6, 2015

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: FIRST INTERSTATE BANCSYSTEM INC (FIBK)
CIK: 0000860413
Period of Report: 2015-05-05

Reporting Person: SULLIVAN MICHAEL J/CO (Director)

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2015-05-05	Stock Options	$15.75	M	2208	Disposed	2015-05-09	Class B Common Stock (2208)	Direct
2015-05-05	Class B Common Stock	$0.00	M	2208	Acquired	2029-12-31	Class A Common Stock (2208)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Class A Common Stock	2829	Indirect
Class A Common Stock	2400	Direct

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Class B Common Stock	$0.00	2029-12-31	Class A Common Stock (16432)	16432	Indirect
Class B Common Stock	$0.00	2029-12-31	Class A Common Stock (3140)	3140	Indirect

Footnotes

F1: The Class B Common Stock is convertible at any time into Class A Common Stock on a share for share basis at the descretion of the holder. The conversion feature of the Class B common stock does not expire.