Company: OSBC
Filing Date: 2025-05-08
Form Type: 424B3
Source: 0001104659-25-046065
Chunk: 30

Company: OLD SECOND BANCORP INC
Filing Date: 2025-05-08
Form: 424B3
Chunk 30
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 Second’s filings with the SEC that are incorporated by reference into this document, including its Annual Report on Form 10-K for the year ended December 31, 2024. For more information on documents incorporated by reference into this proxy statement/prospectus and instructions on how to find copies of these documents, see “Where You Can Find More Information” in the forepart of this proxy statement/prospectus and “Incorporation of Certain Documents by Reference” beginning on page 126.

#### Bancorp Financial, Inc.
1515 West 22nd Street, Suite 100W 
 Oak Brook, Illinois 60523 
 (630) 413-9580

Bancorp Financial, Inc., a Delaware corporation, was founded in 2006 and is headquartered in Oak Brook, Illinois. Bancorp Financial operates as the bank holding company for Evergreen Bank Group, which maintains three banking locations in DuPage and Cook counties in Illinois, and one loan production office in Reno, Nevada. At December 31, 2024, Bancorp Financial had total assets of $1.45 billion, gross loans of $1.21 billion, total deposits of $1.24 billion and total stockholders’ equity of $149.9 million.

Bancorp Financial common stock is not registered under the Securities Exchange Act of 1934, as amended, and, accordingly, the company does not file periodic or current reports with the SEC. More information about Bancorp Financial is available by visiting the “About Us — Shareholder and Financial Information” tab of Evergreen Bank Group’s website at www.evergreenbankgroup.com. Information contained on Evergreen Bank Group’s website does not constitute part of, and is not incorporated into, this proxy statement/prospectus.

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TABLE OF CONTENTS

### CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS
This proxy statement/prospectus and the documents incorporated by reference into this proxy statement/ prospectus contain forward-looking statements regarding Old Second’s and Bancorp Financial’s outlook or expectations with respect to the merger, including the expected costs to be incurred and cost savings to be realized in connection with the merger, the expected impact of the merger on the combined company’s future financial performance, the assumed purchase accounting adjustments, other key transaction assumptions, the timing of the closing of the merger and consequences of the integration of the businesses and operations of Old Second and Bancorp Financial. Words such as “believe,” “expect,” “antic