1
                                                                     EXHIBIT 4.3
                                                                     -----------

                            SECURITY BANC CORPORATION
                            -------------------------

                             1998 STOCK OPTION PLAN
                             ----------------------


         1. NAME AND PURPOSE. This Plan shall be known as the Security Banc
Corporation 1998 Stock Option Plan (the "Plan"). The purpose of the Plan is to
advance the interests of Security Banc Corporation (the "Corporation") by
providing material incentive for the continued services of key employees and by
attracting able personnel to employment with the Corporation and its
Subsidiaries. The term "Subsidiary" as used herein means a subsidiary
corporation (as the term is defined in Section 425(f) of the Internal Revenue
Code of 1986 (the "Code")) of the Corporation.

         2. ADMINISTRATION. The Plan shall be administered by a committee of
directors (the "Committee") designated by the Board of Directors of the
Corporation. The Committee may establish, subject to the provisions of the Plan,
such rules and regulations as it deems necessary for the proper administration
of the Plan, and make such determinations and take such action in connection
therewith or in relation to the Plan as it deems necessary or advisable,
consistent with the Plan.

         3. ELIGIBILITY. Officers and other employees of the Corporation or any
Subsidiary who are designated by the Committee as eligible to participate in the
Plan ("Eligible Employees") shall be eligible to participate in the Plan and
receive options granted under the Plan.

         4. SHARES SUBJECT TO OPTION. (a) The shares to be issued and delivered
by the Corporation upon exercise of options granted under the Plan are the
Corporation's common shares, which may be either authorized but unissued shares
or treasury shares.

         (b) The aggregate number of common shares of the Corporation which may
be issued under the Plan shall not exceed 60,000; subject, however, to the
adjustment provided in Paragraph 8 in the event of stock splits, stock
dividends, exchanges of shares or the like occurring after adoption of this Plan
by the Board of Directors of the Corporation. No option may be granted under
this Plan which could cause such maximum limit to be exceeded.

         (c) Common shares covered by an option which is no longer exercisable
with respect to such shares shall again be available for issuance in connection
with other options granted under this Plan.

         5. GRANT OF OPTIONS. The Committee from time to time, in its discretion
and subject to the provisions of the Plan, may grant options to any or all
Eligible Employees. An Eligible Employee to whom an option has been granted is
referred to herein as an "Optionee." Each option shall be evidenced by an
"Option Agreement," signed by the Optionee and the Corporation, which shall
provide that the option shall be subject to the provisions of this Plan and
shall contain such other provisions as the Committee may prescribe not
inconsistent with this Plan.

         6. TERMS AND CONDITIONS OF OPTION. All options granted under this Plan
shall contain such terms and conditions as the Committee determines at the time
of grant, subject to the foregoing and following limitations and requirements.

         (a) FORM OF OPTION. Incentive Options and Non-Qualified Options may be
granted under this Plan. "Incentive Option" means an option granted under this
Plan which is designated to be an incentive


   2



stock option under the provisions of Section 422 of the Code; and any provisions
elsewhere in this Plan or in the Option Agreement for an Incentive Option which
would prevent such option from being an incentive stock option under the
provisions of Section 422 of the Code may be deleted and/or voided retroactively
to the date of the granting of such option, by action of the Committee.
"Non-Qualified Option" means an option granted under this Plan which is not an
incentive stock option under the provisions of Section 422 of the Code.
Non-Qualified Options shall not be affected by any actions taken retroactively
as provided above with respect to Incentive Options.

         (b) OPTION PRICE. The option price per share shall not be less than
100% of the fair market value of a common share of the Corporation on the date
the option is granted, as determined by the Committee in a manner consistent
with the requirements of the Code for incentive stock options.

         (c) 10% SHAREHOLDER. Notwithstanding any other provisions of this Plan,
with respect to an Incentive Option granted to an Optionee who, at the time such
option is granted, possesses, directly or indirectly, more than 10% of the
voting power of all classes of capital shares of the Corporation, any Subsidiary
or any parent of the Corporation, the option price per share shall be at least
110% of the fair market value of a common share of the Corporation, determined
as provided in Paragraph 6(b) above, and such option shall expire five years
from the date the option is granted.

         (d) PERIOD WITHIN WHICH OPTION MAY BE EXERCISED. Subject to Paragraph
6(c) above, at the time an option is granted, the Committee shall specify the
maximum term during which the option may be exercised and may provide for such
other terms, restrictions, conditions and limitations on the exercise of the
option (including, without limitation, provisions that provide the option may be
exercised in full or in part only after the passage of a specified period or
periods of time or only if specified conditions have been satisfied), if any, as
it may deem appropriate. Notwithstanding any other provision of this Plan,
however, no option may be exercised after the expiration of ten years from the
date the option is granted.

         (e) TERMINATION OF OPTION BY REASON OF TERMINATION OF EMPLOYMENT. If an
Optionee's employment with the Corporation and its Subsidiaries terminates, all
options granted under this Plan to such Optionee which are not exercisable on
the date of such termination of employment shall immediately terminate. Any
remaining options held by such Optionee also shall terminate if not exercised
before the expiration of the following periods, or at such earlier time as the
option may expire by its terms:

                  (i) seven days following the Optionee's termination of
         employment, if such termination was not as a result of the death or
         disability of the Optionee or the retirement of the Optionee under the
         provisions of any retirement plan of the Corporation and/or any
         Subsidiary;

                  (ii) 30 days following the Optionee's termination of
         employment, if such termination was as a result of the retirement of
         the Optionee under the provisions of any retirement plan of the
         Corporation and/or any Subsidiary; or

                  (iii) one year following the Optionee's termination of
         employment, if such termination was as a result of the death or
         disability of the Optionee.


                                       -2-

   3



         (f) TRANSFERABILITY. Each option shall be transferable by the Optionee
only to the extent specified by the Committee at the time the option is granted
and then only to the extent permitted by applicable law (including, without
limitation, the Code).

         (g) MORE THAN ONE OPTION GRANTED TO AN OPTIONEE. More than one option,
and more than one form of option, may be granted to an Optionee under this Plan;
provided, however, that the aggregate fair market value (determined as of the
time the option is granted as provided in Paragraph 6(b) above) of the common
shares with respect to which incentive stock options are exercisable for the
first time by any Optionee during any calendar year under this Plan and all
other plans of the Corporation, any Subsidiary and any parent corporation shall
not exceed $100,000, or such other maximum amount as may be permitted from time
to time by the Code. To the extent that the foregoing limitation would be
exceeded by all or part of an Incentive Option, the excess portion shall
constitute a Non-Qualified Option and not an Incentive Option. A single option
grant may include both an Incentive Option and a Non-Qualified Option.

         (h) COMPLIANCE WITH SECURITIES LAWS. Options granted and shares issued
by the Corporation upon exercise of options shall be granted and issued only in
full compliance with all applicable securities laws, including laws, rules and
regulations of the Securities and Exchange Commission and applicable state Blue
Sky laws. With respect thereto, the Committee may impose such conditions on
transfer, restrictions and limitations as it may deem necessary and appropriate
to assure compliance with such applicable securities laws.

         7. METHOD OF EXERCISE. An option granted under this Plan that is
eligible to be exercised may be exercised by written notice given to the
Committee, signed by the Optionee or by such other person as is entitled to
exercise such option. The notice of exercise shall state the number of common
shares in respect of which the option is being exercised and shall either be
accompanied by payment of the full option price for such common shares or shall
fix a date (not more than ten business days from the date of such notice) for
the payment of the full purchase price of the common shares being purchased. All
or any portion of the option price may be paid by the transfer of common shares
of the Corporation from the Optionee to the Corporation, to the extent permitted
by law. Such shares shall be valued for this purpose at their fair market value
on the date they are transferred to the Corporation as payment, determined in
the same manner as is provided in Paragraph 6(b). A certificate or certificates
for the common shares purchased through the exercise of an option shall be
issued in regular course after the exercise of the option and payment therefor.
No Optionee shall have any of the rights or privileges of a shareholder with
respect to any common shares issuable upon exercise of an option until the
option is duly exercised and certificates representing such shares have been
issued.

         8. SHARE ADJUSTMENTS. In the event there is any change in the
Corporation's common shares resulting from stock splits, stock dividends,
combinations, recapitalizations or exchanges of shares or other similar capital
adjustments, the Committee shall make equitable proportionate adjustments in:
(a) the number of common shares remaining available for option under this Plan,
(b) the number of common shares subject to options granted under this Plan, and
(c) the option price of outstanding options granted under this Plan.

         9. MERGER, CONSOLIDATION, OR SALE OF ASSETS. Unless otherwise
determined by the Committee at the time an option is granted, upon the
occurrence of a Change of Control (as hereinafter defined), each outstanding
option granted under the Plan shall become exercisable in full notwithstanding
any vesting

                                       -3-

   4



schedule or other similar limitation on the right of the Optionee to exercise
such option. For purposes of this Plan, "Change of Control" means a change of
control of a nature that would be required to be reported in response to Item
6(e) of Schedule 14 of Regulation 14A adopted under the Exchange Act or any
similar successor disclosure provisions. Without limiting the foregoing, a
"Change of Control" shall be deemed to have occurred if: (i) any "person," as
such term is used in Section 13(d) and 14(d)(2) of the Exchange Act (excluding,
for this purpose, the Corporation or any Subsidiary or any employee benefit plan
of the Corporation or any Subsidiary), including any "group" of persons, becomes
the beneficial owner (as determined in accordance with Rule 13d-3 adopted under
the Exchange Act), directly or indirectly, of securities of the Corporation
which, together with any other securities of the Corporation theretofore
directly or indirectly beneficially owned by such person, represent 20% or more
of the combined voting power of the Corporation's then outstanding securities;
(ii) at any election or series of elections, persons not proposed for nomination
or nominated by the Board of Directors of the Corporation are elected as
directors of the Corporation and together constitute 20% or more of the number
of directors of the Corporation; or (iii) any person or group solicits and
receives valid proxies for the election of directors in opposition to the
nominees of the Board of Directors of the Corporation representing an aggregate
of 20% or more of the combined voting power of the Corporation's then
outstanding securities.

         10. AUTHORITY OF THE COMMITTEE WITH RESPECT TO OUTSTANDING OPTIONS. (a)
Subject to the limitations set forth in Paragraph 6 with respect to the maximum
term of any option, the Committee may waive or modify at any time, either before
or after the granting of an option, any condition, limitation or restriction
with respect to the exercise of such option imposed by or pursuant to this Plan
in such circumstances as the Committee may, in its discretion, deem appropriate;
provided, however, that any such waiver or modification with respect to an
outstanding option shall be subject to the same limitations applicable to
amendments to outstanding options, as set forth in Paragraph 10(c) below.

         (b) Subject to the other terms and provisions of this Plan, the
Committee may amend any outstanding option; provided, however, that (i) no such
amendment may reduce the option price of the option (except to set forth an
adjustment in the option price made pursuant to Paragraph 8 above) or extend the
maximum term during which the option, if fully vested, may be exercised, and
(ii) if the amendment would adversely affect the rights of the Optionee, the
consent of the Optionee to such amendment must be obtained.

         11. AMENDMENT AND TERMINATION. (a) The Board of Directors of the
Company from time to time may amend this Plan in such respects as it may deem
advisable; provided, however, that any such amendment must be approved by the
holders of the outstanding common shares of the Corporation by such vote (if
any) as then may be required by, and otherwise in compliance with, applicable
federal and state law (including Rule 16b-3 or any successor provision adopted
under the Exchange Act) and the requirements of any stock exchange or other
trading system upon which the common shares of the Corporation then may be
listed.

         (b) The Board of Directors may terminate this Plan at any time.

         (c) No amendment to this Plan nor the termination of this Plan shall
adversely affect any option outstanding at the time of such amendment or
termination without the consent of the Optionee holding such option, and all
such outstanding options shall remain in full force and effect as if the Plan
had not been adversely amended or terminated.

                                       -4-

   5



         12. CORPORATION'S RESPONSIBILITY. All expenses of this Plan, including
the cost of maintaining records, shall be borne by the Corporation. The
Corporation shall have no responsibility or liability for any act or thing done
or left undone with respect to the price, time, quantity, or other conditions
and circumstances of the purchase of common shares under the terms of this Plan,
so long as the Corporation acts in good faith.

         13. IMPLIED CONSENT OF OPTIONEES. Every Optionee, by his acceptance of
an option under this Plan, shall be deemed to have consented to be bound, on his
own behalf and on behalf of his heirs, assigns, and legal representatives, by
all of the terms and conditions of this Plan.

         14. NO EFFECT ON EMPLOYMENT STATUS. The fact that an employee has been
granted an option under this Plan shall not limit or otherwise qualify the right
of his employer to terminate his employment at any time.

         15. SAVING PROVISION. With respect to persons subject to Section 16 of
the Exchange Act, transactions under this Plan are intended to comply with all
applicable conditions of Rule 16b-3 or any successor rule adopted under the
Exchange Act. To the extent any provision of this Plan or any action by the
Board of Directors of the Corporation or the Committee fails to so comply, it
shall be deemed null and void, to the extent permitted by law and deemed
advisable by the Board of Directors of the Corporation or the Committee.

         16. SHAREHOLDER APPROVAL AND TERM OF PLAN. (a) The Plan shall become
effective upon approval by the affirmative vote of the holders of a majority of
the outstanding common shares of the Corporation. By adopting the Plan by such
vote, the holders of the Corporation's common shares waive pre-emptive rights
with respect to the Shares issuable upon exercise of options granted under the
Plan, in accordance with Section 1701.15(A)(8) of the Ohio Revised Code.

         (b) No options shall be granted under this Plan after April 21, 2008 or
after such earlier date as this Plan may be terminated in accordance with
Paragraph 11.


                                        /s/ Harry O. Egger
                                        February 17, 1998


                                       -5-