Document:

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                                  EXHIBIT 4.22

             NINTH AMENDMENT TO SAVINGS AND PROFIT SHARING PLAN FOR
                 EMPLOYEES OF FIRST INTERSTATE BANCSYSTEM, INC.

     The Savings and Profit Sharing Plan for Employees of First Interstate
BancSystem, Inc. (the "Plan") is hereby amended as follows, effective August 1,
2000:

                                    ARTICLE 1

     Section 3.2 of the Plan is modified to read in its entirety as follows:

     3.2 ELIGIBILITY SERVICE. An Employee shall receive credit for one year of
Eligibility Service upon the first to occur of (a) or (b) below:

     (a)  the completion of his initial 12-month period of employment as an
          Employee, provided he has completed at least 1,000 Hours of Service
          during such 12-month period; or

     (b)  the completion of any Plan Year beginning after his Employment
          Commencement Date as an Employee during which he has completed at
          least 1,000 Hours of Service.

     In the case of Employees who were employed by First Citizens Bank of
Bozeman, Montana on January 1, 1995, Eligibility Service shall include Hours of
Service performed for First Citizens Bank of Bozeman, Montana prior to the time
it became an Affiliate. In the case of Employees who were employed by First
National Park Bank, N.A. on July 1, 1995, Eligibility Service shall include
Hours of Service performed for First National Park Bank, N.A. prior to the time
it became an Affiliate. In the case of Employees who were employed in either the
Helena, Montana or Belgrade, Montana branch of the First National Bank of
Montana on the date on which substantially all the operating assets of such
branch were acquired by Company or an Affiliate, Eligibility Service shall
include Hours of Service performed for First National Bank of Montana prior to
such date.

     For purposes of determining the Eligibility Service of an individual who is
an employee of First Interstate Bank of Wyoming, N.A., First Interstate Bank of
Montana, N.A., Mountain Bank, Security State Bank Shares, Security State Bank
and Trust Company, Equality State Bank or Equality Bankshares and Subsidiaries
on the date such organization first becomes an Affiliate, service previously
completed by the individual as an employee of either such organization
(including service for any affiliated or predecessor entity taken into account
for eligibility purposes in a qualified pension or profit sharing plan
maintained by such organization) shall be taken into account to the same extent
as service completed for an Employer.

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                                    ARTICLE 2

     Except as modified herein, all provisions of the Plan shall remain in full
force and effect.

     DATED this 30th day of August, 2000.

                                       FIRST INTERSTATE BANCSYSTEM, INC.

                                       By: /s/ ROBERT A JONES
                                           -------------------------------------
                                       Its:

                                                              "Company"

                                       2<PAGE>   1

                                  EXHIBIT 4.23

             TENTH AMENDMENT TO SAVINGS AND PROFIT SHARING PLAN FOR
                 EMPLOYEES OF FIRST INTERSTATE BANCSYSTEM, INC.

     The Savings and Profit Sharing Plan for Employees of First Interstate
BancSystem, Inc. (the "Plan") is hereby amended as follows, effective January 1,
2001:

                                    ARTICLE 1

     Section 2.1 (ii) of the Plan is amended to read in entirety as follows:

     (ii) "SERVICE" means employment with an Employer, an Affiliate, or a
          predecessor thereof. For purposes of Sections 3.5, 3.6 and 3.7,
          "Service" means Vesting Service.

                                    ARTICLE 2

     A new subsection (oo) is added at the end of Section 2.1 of the Plan,
reading in its entirety as follows:

     (oo) "VESTING SERVICE" means service credited for vesting purposes in
          accordance with Section 5.3.

                                    ARTICLE 3

     A new subsection (pp) is added at the end of Section 2.1 of the Plan,
reading in its entirety as follows:

     (pp) "DISTRIBUTION DATE" means a date as of which a Member's Account may be
          distributed, or commence to be distributed, to him. The business day
          coinciding with or next following the fifteenth day of each calendar
          month shall be a distribution date.

                                    ARTICLE 4

     Section 3.1 of the Plan is modified to read in its entirety as follows:

     3.1 DATE OF PARTICIPATION. Each Employee who is a Participant on December
31, 2000 shall continue to be a Participant in this Plan. Each other Employee
who is or who

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becomes employed by an Employer (an "Eligible Employee") shall become a
Participant on the latest to occur of--

     (a)  January 1, 2001;

     (b)  the first day of the month next following the date the individual
          becomes an Eligible Employee; or

     (c)  in the case of an individual who becomes an Eligible Employee prior to
          January 1, 2001, the first January 1, April 1, July 1 or October 1
          coinciding with or next following the completion of one year of
          Eligibility Service, provided however that this subsection (c) shall
          not apply to an individual who first becomes an Eligible Employee
          during the Plan Year ending December 31, 2000 and makes an election
          during such Plan Year, on a form provided by the Committee, to become
          a Participant on January 1, 2001 and to be subject to the three-year
          vesting schedule provided in Section 5.2(b) with respect to Employer
          Matching Contributions and Profit Sharing Contributions.

An Eligible Employee shall be eligible to make a Rollover Contribution before
becoming a Participant; provided, however, he shall be deemed a Participant to
the extent of the Employee's Rollover Contribution only and not for any other
purposes until the Employee otherwise is eligible to be and becomes a
Participant for all purposes hereunder.

                                    ARTICLE 5

     Section 3.4 of the Plan is modified to read in its entirety as follows:

     3.4 REEMPLOYMENT. A former Participant shall again become a Participant
immediately upon resuming employment with an Employer. A former Employee who did
not make the election described in Section 3.1(c) and who had a termination of
employment and was not a Participant at such termination of employment shall,
upon resuming employment as an Employee, receive credit for the Hours of Service
he had prior to such termination of employment, and such a former Employee who
had met the Eligibility Service requirements of section 3.1(c) prior to his
termination of employment but had not yet become a Participant in the Plan by
reason of his termination before the next occurring January 1, April 1, July 1,
or October 1 shall, upon resuming employment as an Employee after such date,
immediately participate in the Plan.

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                                    ARTICLE 6

     Section 4.2 of the Plan is modified to read in its entirety as follows:

     4.2 ALLOCATION OF EMPLOYER PROFIT SHARING CONTRIBUTIONS. The Employer
Profit Sharing Contributions for each Plan Year shall be allocated and credited
as of the last day of each Plan Year quarter for which the Employer Profit
Sharing Contribution was made to Employer Profit Sharing Contributions Accounts
of Members who are in the employ of the Employer as of that date or who are
Members who retired, died, or incurred a Disability during the Plan Year
quarter, in the proportion of the Compensation of each such Member for that Plan
Year quarter bears to the total of the Compensation of all such Members for that
Plan Year quarter. Only Compensation an individual receives while a Participant
shall be taken into account under this Section.

                                    ARTICLE 7

     Section 4.3 of the Plan is modified to read in its entirety as follows:

     4.3 BEFORE-TAX AND MATCHING CONTRIBUTIONS. For each Plan Year, each
Employer shall contribute an amount equal to the sum of (a) Before-Tax
Contributions and (b) Matching Contributions; the amount of each of which is as
follows:

     (a)  BEFORE-TAX CONTRIBUTIONS. Each Participant may elect, on a form
          provided by the Committee, to reduce his Compensation by whole number
          percentage up to and including 15 percent and to have the amount by
          which his Compensation is reduced contributed on his behalf by his
          Employer as a Before-Tax Contribution to the Plan.

          In the case of a Participant who first becomes an Eligible Employee
          after December 31, 2000, and any Participant who first becomes and
          Eligible Employee during the Plan Year ended December 31, 2000 and
          makes the election provided in Section 3.1(c), if the individual does
          not affirmatively elect to either (1) reduce his Compensation by a
          specified amount to be contributed to the Plan in accordance with the
          preceding paragraph, or (2) NOT reduce his Compensation in accordance
          with the preceding paragraph, then his or her Compensation shall be
          automatically reduced by 1 percent and this amount shall be
          contributed on his behalf by his Employer as a Before-Tax Contribution
          to the Plan.

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          Within a reasonable time after an Eligible Employee described in the
          preceding paragraph is hired, and before the date the Employee becomes
          a Participant, the Employer shall provide the Employee with a notice
          that explains the automatic Compensation reduction election described
          in the preceding paragraph, and the Employee's right to elect to have
          no such Compensation reduction contributions made to the Plan as
          Before-Tax Contributions, or to alter the amount of those
          contributions, including the procedure for exercising that right and
          the timing for implementation of any such election. Each Participant
          shall be notified annually of his or her Compensation reduction
          percentage and the participant's right to change the percentage,
          including the procedure for exercising that right and the timing for
          implementation of any such election.

          A Participant may elect, on a form provided by the Committee, to
          increase or decrease his Compensation reductions (within the
          percentage limits stated above) or to cease future Compensation
          reductions as of the first payday in any month, provided the
          Participant files such form with the Committee prior to the first day
          of the month. The Committee may adopt rules concerning the
          administration of this subsection.

          The Before-Tax Contributions made on behalf of each Participant shall
          be paid to the Trustee every pay period, at the earliest date on which
          they can reasonably be segregated from the Employer's general assets,
          not later than the 15th business day of the month following the month
          in which such amounts would otherwise have been payable to the
          Participant in cash, and shall be allocated to such Participant's
          Account as of the date on which they are received by the Trustee.

     (b)  MATCHING CONTRIBUTIONS. Each Employer shall make a Matching
          Contribution on behalf of each Participant equal to 125 percent of the
          first 4 percent of Before-Tax Contributions made with respect to such
          Participant. The Matching Contributions made on behalf of each
          Participant shall be paid to the Trustee every pay period and
          allocated to such Participant's Matching Contributions Account as of
          the date on which they are received by the Trustee. The amount of
          Matching Contributions shall be adjusted on or before the close of the
          Plan Year, so that the total amount of Matching

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          Contributions made on behalf of each Participant for the Plan Year
          equals 125 percent of the first four percent of Compensation
          contributed by the Participant as a Before-Tax Contribution during the
          Plan Year.

                                    ARTICLE 8

     Section 5.1 of the Plan is modified to read in its entirety as follows:

     5.1 AFTER-TAX, BEFORE-TAX AND ROLLOVER CONTRIBUTIONS ACCOUNTS. A Member
shall at all times be fully vested and have a nonforfeitable interest in his
After-Tax Contributions Account, his Before-Tax Contributions Account and his
Rollover Contributions Account.

                                    ARTICLE 9

     Section 5.2 of the Plan is modified to read in its entirety as follows:

     5.2 EMPLOYER PROFIT SHARING AND MATCHING CONTRIBUTIONS ACCOUNTS

     (a)  GENERAL. A Member who became an Eligible Employee on or before January
          1, 2001, other than a Member who qualifies for and makes the election
          described in Section 3.1(c), shall at all times have a 100 percent
          vested and nonforfeitable interest in his Employer Profit Sharing and
          Matching Contributions Accounts. A Member not described in the
          preceding sentence shall have a zero percent vested and nonforfeitable
          interest in his Employer Profit Sharing and Matching Contributions
          Accounts until the date the Member completes three years of Vesting
          Service, and shall become 100 percent vested in such Accounts on that
          date.

     (b)  ACCELERATED VESTING. Notwithstanding subsection (a) above, a Member
          shall be fully vested and have a nonforfeitable interest in his entire
          Employer Profit Sharing and Matching Contributions Accounts on the
          earliest date on which--

          (1)  he attains his Retirement Age while an Employee;

          (2)  he dies or suffers a Disability while an Employee; or

          (3)  while he is an Employee, contributions to the Plan are completely
               discontinued or the Plan is terminated, or the Plan is partially
               terminated and such Member is affected by such partial
               termination.

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                                   ARTICLE 10

     Section 5.3 of the Plan is modified to read in its entirety as follows:

     5.3 VESTING SERVICE. A Member shall be credited with one year of Vesting
Service for each Plan Year in which the individual completed at least 1000 Hours
of Service, subject to the following rules:

          (a)  Years of Vesting Service completed after a period of One-Year
               Breaks in Service shall not be required to be taken into account
               for purposes of determining the non-forfeitable percentage of a
               Member's accrued benefit derived from contributions which
               occurred prior to such period if the number of consecutive
               One-Year Breaks in Service within such period equals or exceeds
               five.

          (b)  In the case of a Participant who does not have any nonforfeitable
               right to an accrued benefit under the Plan, Years of Service with
               the Employer before a One-Year Break in Service shall not be
               taken into account if the number of consecutive One-Year Breaks
               in Service equals or exceeds five, or if greater, the aggregate
               number of Years of Service before such period. If any Years of
               Service are not required to be taken into account by reason of a
               period of One-Year Breaks in Service to which this paragraph
               applies, such Years of Service shall not be taken into account in
               applying this paragraph to a subsequent period of One-Year Breaks
               in Service.

                                   ARTICLE 11

     Section 5.4 of the Plan is modified to read in its entirety as follows:

     5.4 FORFEITURE OF NONVESTED AMOUNTS. If any portion of a Participant's
Account is non-vested upon the Participant's separation from Service, the
non-vested amount shall be retained in such Account until the earlier of the
following events:

          (a)  the terminated Participant incurs five consecutive One-Year
               Breaks in Service, or

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          (b)  prior to the close of the second Plan Year following the Plan
               Year in which the Participant separates from Service, the
               terminated Participant receives a distribution of his entire
               nonforfeitable accrued benefit under the Plan.

     Upon the occurrence of the earlier of the events specified in (a) and (b),
the non-vested portion of the terminated Participant's Account shall be
immediately forfeited and shall be transferred to a separate Forfeiture account
until reallocated in accordance with this Section.

     In the event the non-vested portion of a terminated Participant's Account
is forfeited upon a distribution of such Participant's entire nonforfeitable
accrued benefit, the amount forfeited shall be restored to the Participant's
Account, unadjusted for gains or losses of the Trust subsequent to the
distribution, if the Participant is reemployed by the Employer or an Affiliate
and repays the amount of the distribution before the earlier of five years after
the date on which the Participant is first subsequently reemployed by the
Employer or Affiliate, or the close of the first period of five consecutive
One-Year Breaks in Service commencing after the distribution.

     For purposes of this Section, a Participant who has no vested interest in
his Account at the time of separation from Service shall be deemed to have
received a distribution of his entire nonforfeitable accrued benefit under the
Plan at such time, and shall be deemed to have repaid the amount of such
distribution at the time of any subsequent employment of the individual by the
Employer or an Affiliate.

     Amounts forfeited hereunder during any Plan Year shall be reallocated, as
of the last day of the Plan Year, among the Accounts of reemployed Participants
to the extent this Section 5.4 requires the restoration to such Accounts of
amounts previously forfeited. If amounts forfeited during the Plan Year do not
equal or exceed the amount of restorations required for the Plan year, the
Employer shall contribute, in addition to the contribution provided in Section
3.1, the amount necessary to fund such required restorations. The Employer's
contribution shall be made no later than the close of the Plan Year next
following the Plan Year during which such restorations are required. To the
extent not reallocated among the Accounts of reemployed Participants, amounts
forfeited under this paragraph shall be applied to reduce future Employer
Matching and/or Profit Sharing Contributions.

                                   ARTICLE 12

     A new Section 5.5 is added to the Plan, reading in its entirety as follows:

     5.5 VESTING AFTER IN-SERVICE DISTRIBUTION. If a distribution is made at a
time when a Participant has a nonforfeitable right to less than 100 percent of
the Account

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balance derived from Employer contributions and the Participant may increase the
nonforfeitable percentage in the Account:

     (a) A separate account will be established for the Participant's interest
in the plan as of the time of the distribution, and

     (b) At any relevant time the Participant's nonforfeitable portion of the
separate account will be equal to an amount ("X") determined by the formula:

      X = P(AB + D) - D

     For purposes of applying the formula: P is the nonforfeitable percentage at
the relevant time, AB is the Account balance at the relevant time, and D is the
amount of the distribution. Notwithstanding subsection (a), the Plan shall not
be required to provide for separate Accounts provided that Account balances are
maintained under a method that has the same effect as under Section.

                                   ARTICLE 13

     The second paragraph of Section 6.2 of the Plan is modified to read in its
entirety as follows:

     When a Member receives a distribution of the entire vested portion of his
Accounts pursuant to this Section 6.2, the portions of his Employer Profit
Sharing and Matching Contributions Accounts which are not vested as of his
termination of employment shall become a Forfeiture if and to the extent
provided in Section 5.4.

                                   ARTICLE 14

     The following sentence is added at the end of Section 6.3 of the Plan:

     Subject to Section 6.6, a distribution under Section 6.1 or 6.2 shall be
made or commence as of the first Distribution Date following the month in which
the Member separated from Service or, if the distribution is one which requires
the consent of the Member under Section 6.4, any Distribution Date thereafter as
elected by the Member.

                                   ARTICLE 15

     Section 7.3 of the Plan is modified to read in its entirety as follows:

     7.3 INVESTMENT ELECTIONS. Each Member may make the elections described in
section 7.1 and change such elections upon first becoming a Participant, and
from time to time in accordance with procedures established by the Committee.
The Committee may permit the making and changing of such elections through the
completion and filing of election forms, or through internet and/or voice
response facilities, or any combination of the foregoing, provided that the
election procedures shall permit Members and Beneficiaries to give investment
instructions no less frequently than once within any three month period. If a
Member fails to make an election, that Member shall be deemed to have elected to
invest in a default Investment Fund or model portfolio selected by the
Committee.

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                                   ARTICLE 16

     Section 8.5 of the Plan is modified to read in its entirety as follows:

     8.5 DIVIDENDS. As of the end of each calendar quarter, any cash stock
dividend declared during such calendar quarter shall be invested on the Member's
behalf in accordance with the Member's current investment directive in effect
under Section 7.3.

                                   ARTICLE 17

     Except as modified herein, all provisions of the Plan shall remain in full
force and effect.

     DATED this 29th day of December, 2000.

                                       FIRST INTERSTATE BANCSYSTEM, INC.

                                       By: /s/  ROBERT A. JONES
                                           -------------------------------------
                                       Its:

                                                            "Company"

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