Company: OSBC
Filing Date: 2025-04-23
Form Type: S-4
Source: 0001104659-25-037832
Chunk: 378

Company: OLD SECOND BANCORP INC
Filing Date: 2025-04-23
Form: S-4
Chunk 378
---
Attest:

Name:

Title: Secretary

<div align='center'>B-1-4</div>

TABLE OF CONTENTS

### EXHIBIT C

### FORM OF EMPLOYMENT AGREEMENT

### EXECUTIVE EMPLOYMENT AGREEMENT
This EMPLOYMENT AGREEMENT (the “

#### Agreement
”) is entered into effective as of [ , 2025] (“

#### Effective Date
”), by and between OLD SECOND BANCORP, INC. (the “

#### Company
”) and DARIN CAMPBELL (the “

#### Executive
”).

### RECITALS

### WHEREAS
, the Company and its wholly-owned subsidiary, Old Second National Bank (the “

#### Bank
”) are presently engaged in the general business of providing community banking and trust business services. The Bank’s services include, but are not limited to demand, savings, time deposit, individual retirement, and Keogh deposit accounts; commercial, industrial, consumer, and real estate lending, including installment loans, farm loans, lines of credit, and overdraft checking; safe deposit operations; and trust services. The Bank is also in the business of providing services such as the sale of traveler’s checks, money orders, cashier’s checks and foreign currency, direct deposit, discount brokerage, debit cards, credit cards, and other special services; and

### WHEREAS
, the Executive is currently employed by Bancorp Financial, Inc., pursuant to that certain Amended and Restated Employment Agreement dated December 3, 2024 (the “

#### Prior Employment Agreement
”); and

### WHEREAS
, at the Effective Time (as defined in the Merger Agreement) (the

#### “Effective Time”
), Bancorp Financial, Inc. and Evergreen Bank Group will merge with and into the Company and Bank, respectively, pursuant to that certain Agreement and Plan of Merger dated [ ], 2025 (the “

#### Merger Agreement
”), and the Bank Merger Agreement (as defined in the Merger Agreement); and

### WHEREAS
, the Company has agreed to appoint Executive to its Boards (as defined below) and wishes to continue Executive’s employment and the Executive desires to serve on the Boards and continue employment with the Company under the terms and provisions set forth below; and

### WHEREAS
, the Company and the Executive desire to enter into this Agreement to provide certain benefits to the Executive and certain protections for the Bank, subject to and in accordance with this Agreement;