Company: OSBC
Filing Date: 2025-04-23
Form Type: S-4
Source: 0001104659-25-037832
Chunk: 397

Company: OLD SECOND BANCORP INC
Filing Date: 2025-04-23
Form: S-4
Chunk 397
---
IVE’S ACTIVITIES FOLLOWING ANY TERMINATION OF EMPLOYMENT OR SERVICE WITH THE COMPANY AND THE BANK. THE EXECUTIVE IS ADVISED TO CONSULT WITH AN ATTORNEY BEFORE ENTERING INTO THESE COVENANTS AND SHALL BE ALLOWED AT LEAST FOURTEEN (14) CALENDAR DAYS TO REVIEW THE COVENANT (PROVIDED THAT THE EXECUTIVE MAY CHOOSE TO EXECUTE THIS AGREEMENT EARLIER). THE EXECUTIVE AND THE COMPANY, BY ITS DESIGNATED REPRESENTATIVE, HEREBY ACKNOWLEDGE THAT THEY HAVE READ AND UNDERSTAND EACH OF THE PROVISIONS OF THIS AGREEMENT, THAT THEY HAVE EXECUTED THIS AGREEMENT VOLUNTARILY AND WITH FULL KNOWLEDGE OF ITS SIGNIFICANCE, AND THAT THEY INTEND TO BE FULLY BOUND BY THE SAME.

| ​ | OLD SECOND BANCORP, INC. |   |   |                                  | ​ | ​ | DARIN CAMPBELL |   |   |   | ​ |
| ​ | By:                      | ​ | ​ | ​                                | ​ | ​ | By:            | ​ | ​ | ​ | ​ |
| ​ | ​                        | ​ | ​ | Chris Lasse, SVP Human Resources | ​ | ​ | ​              | ​ | ​ | ​ | ​ |
| ​ | Date:                    | ​ | ​ | ​                                | ​ | ​ | Date:          | ​ | ​ | ​ | ​ |

C-1-12

TABLE OF CONTENTS

### EXHIBIT A
<div align='center'>[ Omitted pursuant to Item 601(b)(2) of Regulation S-K ]

C-1-13</div>

TABLE OF CONTENTS

### COMPENSATION AND BENEFITS

### ASSURANCE AGREEMENT

#### Darin Campbell

### EXECUTIVE
<div align='center'>C-1-14</div>

TABLE OF CONTENTS

### COMPENSATION AND BENEFITS ASSURANCE AGREEMENT
This COMPENSATION AND BENEFITS ASSURANCE AGREEMENT (this “

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

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

#### Company
”) and DARIN CAMPBELL (hereinafter referred to as the “

#### Executive
”).

WHEREAS