Company: OSBC
Filing Date: 2025-05-06
Form Type: S-4/A
Source: 0001104659-25-045103
Chunk: 438

Company: OLD SECOND BANCORP INC
Filing Date: 2025-05-06
Form: S-4/A
Chunk 438
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 responding to the request.

(9) To supply by means of a post-effective amendment all information concerning a transaction, and the company being acquired involved therein, that was not the subject of, and included in, this registration statement when it became effective.

(10) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission, such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question of whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

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SIGNATURES Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Aurora, State of Illinois, on May 6, 2025. OLD SECOND BANCORP, INC. By: /s/ James L. Eccher James L. Eccher
Chairman, President and Chief Executive Officer Pursuant to the requirements of the Securities Act of 1933, as amended, the Registration Statement has been signed below by the following persons in the capacities set forth below and on May 6, 2025:

| ​ | Signature            | ​ | ​ | Title                                                                                                                      | ​ |
| ​ | /s/ James L. Eccher  
 ​                    
 James L. Eccher      | ​ | ​ | Chairman, President and Chief Executive Officer                                                                            | ​ |
| ​ | /s/ Bradley S. Adams 
 ​                    
 Bradley S. Adams     | ​ | ​ | Executive Vice President, Chief Financial Officer and Chief Operating Officer (