[Form 4] FIRST INTERSTATE BANCSYSTEM INC Insider Trading Activity

Rhea-AI Filing Summary

First Interstate BancSystem (FIBK) reported an equity grant to its Chief Banking Officer on September 10, 2025. The filing shows 2,308 shares acquired, corresponding to shares issuable upon vesting of restricted stock units granted under the company’s 2023 Equity and Incentive Plan.

The award carries a reported price of $32.49. These RSUs vest in three equal annual installments beginning on September 10, 2026, subject to continued employment through each vesting date. Following the reported transaction, the officer beneficially owned 2,308 shares, held directly.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Shepler Christopher L.

(Last) (First) (Middle)

401 N. 31ST ST.

(Street)

BILLINGS MT 59101

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
FIRST INTERSTATE BANCSYSTEM INC [ FIBK ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Banking Officer

3. Date of Earliest Transaction (Month/Day/Year)
09/10/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	09/10/2025		A		2,308(1)	A	$32.49	2,308	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Shares issuable upon vesting of restricted stock units granted to the reporting person pursuant to the Registrant's 2023 Equity and Incentive Plan. The restricted stock units vest in three equal annual installments beginning on September 10, 2026, subject to the reporting person's continued employment through each applicable vesting date.

Remarks:

	/s/ Kirk D. Jensen, Attorney-in-Fact for Reporting Person	10/09/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did First Interstate BancSystem (FIBK) disclose in this Form 4?

An equity grant to the Chief Banking Officer representing 2,308 shares issuable upon vesting of RSUs.

How many RSUs were granted to the FIBK Chief Banking Officer?

2,308 shares were reported as acquired, tied to RSUs under the 2023 plan.

What is the vesting schedule for the FIBK RSUs?

They vest in three equal annual installments beginning on September 10, 2026, subject to continued employment.

What price is associated with the reported RSU grant?

The filing lists a price of $32.49.

How many shares did the officer own after the transaction?

Beneficial ownership following the transaction was 2,308 shares, held directly.

Under which plan were the RSUs granted?

The award was granted pursuant to FIBK’s 2023 Equity and Incentive Plan.

What was the transaction code in the Form 4?

The transaction code was A (award/acquisition).