First Interstate BancSystem, Inc.
US ˙ NasdaqGS ˙ US32055Y2019

SecurityFIBK / First Interstate BancSystem, Inc.
InstitutionSei Investments Co
Latest Disclosed Ownership433,462 shares
Latest Disclosed Value $ 14,997,762
Sei Investments Co reports 19.31% increase in ownership of FIBK / First Interstate BancSystem, Inc.

On February 13, 2026 - Sei Investments Co filed a 13F-HR form disclosing ownership of 433,462 shares of First Interstate BancSystem, Inc. (US:FIBK) valued at $14,997,785 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 13, 2025 disclosing 363,309 shares of First Interstate BancSystem, Inc.. This represents a change in shares of 19.31% during the quarter. The current value of the position is $14,876,416 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-02-13 2025-12-31 13F FIRST INTST BANCSYSTEM COM 32055Y201 433,462 70,153 19.31 14,998 29.53 0.0148
2025-11-13 2025-09-30 13F FIRST INTST BANCSYSTEM COM 32055Y201 363,309 -14,198 -3.76 11,579 6.43 0.0125
2025-08-14 2025-06-30 13F FIRST INTST BANCSYSTEM COM 32055Y201 377,507 -139,284 -26.95 10,880 -26.52 0.0126
2025-05-14 2025-03-31 13F/A-1 FIRST INTST BANCSYSTEM COM 32055Y201 516,791 -48,682 -8.61 14,806 -19.36 0.0191
2025-05-13 2025-03-31 13F FIRST INTST BANCSYSTEM COM 32055Y201 565,985 512 18,311 0.0199
2025-02-11 2024-12-31 13F FIRST INTST BANCSYSTEM COM 32055Y201 565,473 24,212 4.47 18,361 10.57 0.0236
2024-11-12 2024-09-30 13F FIRST INTST BANCSYSTEM COM 32055Y201 541,261 104,407 23.90 16,606 36.88 0.0216
2024-08-13 2024-06-30 13F FIRST INTST BANCSYSTEM COM 32055Y201 436,854 -11,304 -2.52 12,131 -0.52 0.0172
2024-05-07 2024-03-31 13F FIRST INTST BANCSYSTEM COM 32055Y201 448,158 24,552 5.80 12,194 -6.38 0.0179
2024-02-14 2023-12-31 13F FIRST INTST BANCSYSTEM COM 32055Y201 423,606 -2,008 -0.47 13,026 22.72 0.0209
2023-11-14 2023-09-30 13F FIRST INTST BANCSYSTEM COM 32055Y201 425,614 46,218 12.18 10,615 17.36 0.0191
2023-08-11 2023-06-30 13F FIRST INTST BANCSYSTEM COM 32055Y201 379,396 26,129 7.40 9,045 -14.27 0.0158
2023-05-12 2023-03-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 353,267 128,050 56.86 10,549 21.20 0.0196
2023-02-10 2022-12-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 225,217 -11,875 -5.01 8,705 -9.02 0.0193
2022-11-14 2022-09-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 237,092 1,584 0.67 9,567 6.60 0.0213
2022-08-15 2022-06-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 235,508 128,760 120.62 8,975 128.37 0.0194
2022-05-13 2022-03-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 106,748 96,887 982.53 3,930 880.05 0.0079
2022-02-14 2021-12-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 9,861 -180 -1.79 401 -0.99 0.0008
2021-11-12 2021-09-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 10,041 -123 -1.21 405 -5.15 0.0008
2021-08-06 2021-06-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 10,164 -7,038 -40.91 427 -42.99 0.0009
2021-05-12 2021-03-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 17,202 364 2.16 749 9.18 0.0019
2021-02-08 2020-12-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 16,838 9,194 120.28 686 182.30 0.0018
2020-12-04 2020-09-30 13F/A-1 FIRST INTST BANCSYSTEM COM CL A 32055Y201 7,644 -4,202 -35.47 243 -33.79 0.0007
2020-11-06 2020-09-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 7,644 -4,202 243 585.0900
2020-08-17 2020-06-30 13F/A-1 FIRST INTST BANCSYSTEM COM CL A 32055Y201 11,846 -13,132 -52.57 367 -44.14 0.0011
2020-08-11 2020-06-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 11,945 -13,033 469 1,272.1875
2020-05-14 2020-03-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 24,978 4,973 24.86 657 -15.98 0.0024
2020-02-06 2019-12-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 20,005 1,197 6.36 782 13.66 0.0023
2019-11-12 2019-09-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 18,808 -13,991 -42.66 688 -43.84 0.0018
2019-08-14 2019-06-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 32,799 1,315 4.18 1,225 3.29 0.0040
2019-05-15 2019-03-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 31,484 17,994 133.39 1,186 131.19 0.0040
2019-02-13 2018-12-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 13,490 4,184 44.96 513 23.02 0.0018
2018-11-08 2018-09-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 9,306 -215 -2.26 417 3.73 0.0015
2018-08-03 2018-06-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 9,521 -5,146 -35.09 402 -30.69 0.0014
2018-05-11 2018-03-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 14,667 651 4.64 580 3.39 0.0022
2018-02-08 2017-12-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 14,016 9,090 184.53 561 196.83 0.0019
2017-11-06 2017-09-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 4,926 -4,651 -48.56 189 -46.91 0.0007
2017-07-31 2017-06-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 9,577 6,423 203.65 356 184.80 0.0014
2017-05-05 2017-03-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 3,154 168 5.63 125 -1.57 0.0005
2017-02-02 2016-12-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 2,986 229 8.31 127 45.98 0.0006
2016-11-04 2016-09-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 2,757 808 41.46 87 58.18 0.0004
2016-08-11 2016-06-30 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 1,949 1,549 387.25 55 358.33 0.0003
2016-05-10 2016-03-31 13F/A-1 FIRST INTST BANCSYSTEM COM CL A 32055Y201 400 -12,858 -96.98 12 -96.88 0.0001
2016-02-03 2015-12-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 13,258 7,633 135.70 385 145.22 0.0023
2015-11-02 2015-09-30 13F/A-1 FIRST INTST BANCSYSTEM COM CL A 32055Y201 5,625 5,625 0.00 157 0.0014
2015-10-30 2015-09-30 13F DIREXION SHS ETF TR COM CL A 32055Y201 5,625 157
2015-05-01 2015-03-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 0 -6,249 -100.00 0 -100.00
2015-02-10 2014-12-31 13F FIRST INTST BANCSYSTEM COM CL A 32055Y201 6,249 6,249 174 0.0015
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.