<PAGE>

                                                                   EXHIBIT 10(f)

                               SECOND AMENDMENT TO
                  REPUBLIC BANCORP INC. 1997 STOCK OPTION PLAN

         WHEREAS, REPUBLIC BANCORP INC., a Michigan corporation (the "Company"),
has previously adopted the Republic Bancorp Inc. 1997 Stock Option Plan, as
amended (the "Plan");

         WHEREAS, pursuant to Article M of the Plan, the Company's Board of
Directors may amend the Plan; and

         WHEREAS, the Company's Board of Directors now desires to amend the
Plan.

         NOW, THEREFORE, IN CONSIDERATION of the premises and by resolution of
the Company's Board of Directors, the Plan is hereby amended as follows:

         1.       A new Section 9 of Article G shall be added to the Plan and
shall read in its entirety as follows:

                  "9.      Change in Control.  In the event of any "Change in
Control" (as defined below):

                           (a) the vesting period of all unvested and partially
         vested Options held by Participants who are then designated by the
         Committee as "senior management" personnel of the Company shall
         automatically be accelerated, and all such Options shall be exercisable
         in full immediately from and after the time of such Change in Control;

                           (b) if the employment of any Participant who is not
         at the time of such Change in Control designated by the Committee as
         "senior management" of the Company shall be terminated by the Company
         without cause within one (1) year following such Change in Control,
         then the vesting period of all unvested and partially vested Options
         held by such Participant shall automatically be accelerated, and all
         such Options shall be exercisable in full immediately upon, from and
         after the date of termination of employment

                  For purposes of this Plan, a "Change in Control" occurs on the
         first day any one or more of the following occurs:

                           (A) any person (as such term is used in Sections
         13(d) and 14(d)(2) of the Securities Exchange Act of 1934, as amended
         (the "Exchange Act")), together with all affiliates and associates of
         such person (as such terms are defined in Rule 12b-2 under the Exchange
         Act) becomes the direct or indirect beneficial owner (within the
         meaning of Rule 13d-3 under the Exchange Act) of securities of the
         Company representing (x) 40% or more of the combined voting power of
         all of the Company's outstanding securities entitled to vote generally
         in the election of the Company's directors, or (y) 40% or more of the
         combined shares of the Company's capital stock then outstanding, all
         except in connection with any merger, consolidation, reorganization or
         share exchange involving the Company;


                           (B) the consummation of any merger, consolidation,
         reorganization or share exchange involving the Company, unless the
         holders of the Company's capital stock outstanding immediately before
         such transaction own more than 50% of the combined outstanding shares
         of capital stock and have more than 50% of the combined voting power in
         the surviving entity after such transaction and they own such
         securities in substantially the same proportions (relative to each
         other) as they owned the Company's capital stock immediately before
         such transaction; or

                           (C) the consummation of any sale or other disposition
         (in one transaction or a series of related transactions) of all, or
         substantially all, of the Company's assets to a person whose
         acquisition of 40% or more of the combined shares of the Company's
         capital stock then outstanding would have caused a Change in Control
         under paragraph (A)."
<PAGE>

         2.     Article I of the Plan is hereby  amended by (a)  changing  the
title of such  Article to "RIGHTS IN EVENT OF DEATH OR CHANGE IN CONTROL," (b)
inserting the  subheading  "1. Death." prior to the existing text of Article I,
and (c) adding the following to the end of Article I:

                          "2. Change in Control. If the employment of a
         Participant is terminated by the Company within one (1) year following
         a "Change in Control" (as defined in Section G.9), the Participant's
         Options, to the extent the same are exercisable upon the date of the
         termination of employment, shall be exercisable for a period of ninety
         (90) days following the date of the termination of the Participant's
         employment; provided, however, that in no event shall the Options be
         exercisable more than ten (10) years from the date they were granted."

         3.       Section G, "Terms and Conditions of Option", paragraph 6
thereof, is amended to provide as follows:

         "6.      Option Period and Limitations on Exercise of Options. The
         Committee may, in its discretion, provide that an Option may not be
         exercised in whole or in part for any period or periods of time
         specified in the Option Agreement. The following additional conditions
         shall pertain to Options granted under this Plan subsequent to July 15,
         1999:


                          (a)    Except as otherwise provided in the Option
Agreement, the right to purchase Stock pursuant to an Option Agreement shall
become vested in accordance with the following schedule:


                  Percentage of Shares Covered       Time Elapsed Since
                  By the Option Agreement            Option Grant Date
                  -----------------------            -----------------

                           0%                           Less than 1 year
                          25%                           1 but less than 2 years
                          50%                           2 but less than 3 years
                          75%                           3 but less than 4 years
                         100%                           4 years or more;

                          provided, that the Committee may vary or omit the
                          above vesting requirements in its discretion.

                  (b)     All Option granted hereunder may be exercised, to the
                          extent vested, in whole or in part, at any time during
                          its term. No Option may be exercised after the
                          expiration of ten (10) years from the date it is
                          granted. Notwithstanding anything herein to the
                          contrary, in the event an Incentive Stock Option is
                          granted to a Participant who, at the time such
                          Incentive Stock Option is granted, is a Ten-Percent
                          Shareholder, then such Incentive Stock Option shall
                          not be exercisable more than five (5) years from the
                          date of grant and shall be subject to earlier
                          termination as hereinafter provided. No Option may be
                          exercised for a fractional share of stock."

         The foregoing Second Amendment was approved by the Company's Board of
Directors on October 21, 1999.

                                        ATTEST


                                       /s/ Dana M. Cluckey
                                       ------------------------------------
                                           Dana M. Cluckey, President