Company: OSBC
Filing Date: 2025-05-06
Form Type: S-4/A
Source: 0001104659-25-045103
Chunk: 434

Company: OLD SECOND BANCORP INC
Filing Date: 2025-05-06
Form: S-4/A
Chunk 434
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 above, or in defense of any claim, issue or matter therein, the corporation must indemnify such person against expenses (including attorneys’ fees) actually and reasonably incurred in connection therewith.

#### Certificate of Incorporation and Bylaws
. Article VIII of the Old Second certificate of incorporation provides that Old Second shall indemnify its directors and officers to the fullest extent permitted by the DGCL. Section 8.8 of the Old Second bylaws similarly provides for the indemnification of directors and officers to the fullest extent permitted by law, and permits the advancement of expenses under certain conditions.

#### Liability Insurance
. Old Second maintains directors’ and officers’ liability insurance, which provides coverage against certain liabilities, including liabilities under the Securities Act of 1933, as amended, subject to the terms and conditions of the policy.

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TABLE OF CONTENTS

ITEM 21. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES.

| ​ 
 ​ 
 ​ | Exhibit 
     2.1 
     3.1 | ​ 
 ​ 
 ​ | ​ 
 ​ 
 ​ | Description                                                                                                                                                                                                                                                                                              
 Agreement and Plan of Merger, dated as of February 24, 2025, by and between Old Second Bancorp, Inc. and Bancorp Financial, Inc. (attached as Annex A to the proxy statement/​prospectus forming a part of this Registration Statement).†                                                                
 Restated Certificate of Incorporation of Old Second Bancorp, Inc. (incorporated by reference to Exhibit 3.1 of the Company’s Annual Report on Form 10-K filed on March 11, 2016).                                                                                                                        | ​ 
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 ​ |
|:--|--------:|:--|:--|:---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|:--|
| ​ |     3.2 | ​ | ​ | Amendment to Old Second Bancorp, Inc.’s Restated Certificate of Incorporation (incorporated by reference to Exhibit 3.1 of the Company’s Current Report on Form 8-K filed on May 22, 2019).                                                                                                              | ​ |
| ​ |     3.3 | ​ | ​ | Certificate of Elimination Eliminating References to Series A Junior Participating Preferred Stock from the Restated Certificate of Incorporation, as Amended, of Old Second Bancorp. Inc. (incorporated by reference to Exhibit 3.1 of the Company’s Current Report on Form 8