Company: OSBC
Filing Date: 2025-04-23
Form Type: S-4
Source: 0001104659-25-037832
Chunk: 125

Company: OLD SECOND BANCORP INC
Filing Date: 2025-04-23
Form: S-4
Chunk 125
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ORS AS TO THE SPECIFIC TAX CONSEQUENCES TO THEM OF THE MERGER, INCLUDING TAX RETURN REPORTING REQUIREMENTS, THE APPLICABILITY AND EFFECT OF NON-U.S., FEDERAL, STATE, LOCAL, AND OTHER APPLICABLE TAX LAWS, AND THE EFFECT OF ANY PROPOSED CHANGES IN THE TAX LAWS.**

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TABLE OF CONTENTS

### UNAUDITED PRO FORMACONDENSED COMBINED CONSOLIDATED FINANCIAL INFORMATION
The following tables show the condensed combined financial information for each of Old Second and Bancorp Financial, as well as unaudited pro forma condensed combined financial information for Old Second and Bancorp Financial reflecting the merger, for the year ended December 31, 2024, and pro forma adjustments described in the accompanying notes.

Except as otherwise noted in the footnotes to the tables, (a) the financial information included under the “Old Second Historical” column is derived from Old Second’s historical unaudited interim condensed financial statements and accompanying notes included in Old Second’s Annual Report on Form 10-K for the year ended December 31, 2024, which is incorporated by reference herein, and (b) the financial information under the “Bancorp Financial Historical” column is derived from Bancorp Financial’s historical audited financial statements and accompanying notes for the year ended December 31, 2024, which is included elsewhere in this proxy statement/prospectus.

The unaudited pro forma condensed combined financial information has been prepared to give effect to the following:

•

The acquisition of Bancorp Financial by Old Second under the provision of Financial Accounting Standard Board (FASB) Accounting Standards Codification, ASC 805, “Business Combinations” where the sale of assets and liability of Bancorp Financial will be recorded by Old Second at their respective fair values as of the date the merger is completed;

•

The distribution of shares of Old Second common stock to Bancorp Financial stockholders in exchange for shares of Bancorp Financial common stock (based on a 2.5814 exchange ratio) and $15.93 in cash per share, without interest;

•

Certain reclassifications to conform historical Bancorp Financial’s financial information presentation to Old Second; and

•

Transaction costs in connection with the merger.

The accompanying unaudited pro forma condensed combined balance sheet as of December 31, 2024 combines the historical consolidated balance sheets of Old Second and Bancorp Financial, presenting the merger as if it had been consum