Company: OSBC
Filing Date: 2025-04-23
Form Type: S-4
Source: 0001104659-25-037832
Chunk: 124

Company: OLD SECOND BANCORP INC
Filing Date: 2025-04-23
Form: S-4
Chunk 124
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 24%) may, under certain circumstances, apply unless a U.S. holder (a) is a corporation or is within certain other exempt categories and, when required, demonstrates this fact, or (b) provides a correct taxpayer identification number, certifies as to no loss of exemption from backup withholding and otherwise complies with applicable requirements of the backup withholding rules. A U.S. holder who does not provide his, her or its correct taxpayer identification number may be subject to penalties imposed by the IRS. Any amounts withheld under the backup withholding rules are not an additional tax and generally may be allowed as a refund or a credit against the U.S. holder’s U.S. federal income tax liability, provided such U.S. holder timely furnishes the required information to the IRS.

#### Reporting Requirements.
A U.S. holder will be required to retain records pertaining to the merger and will be required to file with such U.S. holder’s U.S. federal income tax return for the year in which the merger takes place a statement setting forth certain facts relating to the merger. In addition, each U.S. holder who is a “significant holder” that receives Old Second common stock in the merger will be required to file a

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**TABLE OF CONTENTS

statement with his, her or its U.S. federal income tax return for the year of the merger setting forth the names and employer identification numbers of Old Second and Bancorp Financial, the date of the merger, such shareholder’s adjusted tax basis in the Bancorp Financial common stock surrendered (determined immediately prior to the exchange) and the fair market value of the Old Second common stock received in the merger. A “significant holder” is a holder of Bancorp Financial common stock who receives Old Second common stock in the merger and who, immediately before the merger, owned at least one percent (by vote or value) of the outstanding shares of Bancorp Financial common stock or owned Bancorp Financial securities with an adjusted tax basis of at least $1.0 million.

THE PRECEDING DISCUSSION IS INTENDED ONLY AS A SUMMARY OF THE MATERIAL UNITED STATES FEDERAL INCOME TAX CONSEQUENCES OF THE MERGER AND DOES NOT PURPORT TO BE A COMPLETE ANALYSIS OR DISCUSSION OF ALL POTENTIAL INCOME TAX EFFECTS RELEVANT THERETO OR A DISCUSSION OF ANY OTHER TYPE OF TAXES. BANCORP FINANCIAL STOCKHOLDERS ARE URGED TO CONSULT THEIR OWN TAX ADVIS