Company: OSBC
Filing Date: 2025-05-08
Form Type: 424B3
Source: 0001104659-25-046065
Chunk: 23

Company: OLD SECOND BANCORP INC
Filing Date: 2025-05-08
Form: 424B3
Chunk 23
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 vote 1,020,812 shares of Bancorp Financial common stock, representing approximately 36.3% of the shares of Bancorp Financial common stock issued and outstanding on that date.

As of the Bancorp Financial record date, Old Second did not beneficially hold any shares of Bancorp Financial common stock.

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TABLE OF CONTENTS

### Bancorp Financial Voting Agreements (page 75)
In connection with the merger agreement, certain stockholders of Bancorp Financial, including each director of Bancorp Financial, and certain other officers and stockholders of Bancorp Financial, entered into voting agreements with Old Second, which we refer to as the “Voting Agreements,” in which he or she has agreed, among other things, to vote the shares of Bancorp Financial common stock owned beneficially or of record by such stockholder in favor of the merger proposal and the stockholders agreement amendment proposal. As of the Bancorp Financial record date, there were 1,037,927 shares, representing 36.9%, of the Bancorp Financial common stock issued and outstanding subject to Voting Agreements.

Interests of Bancorp Financial Directors and Executive Officers in the Merger (page 56)

In considering the recommendation of the Bancorp Financial board of directors with respect to the merger, Bancorp Financial stockholders should be aware that certain of Bancorp Financial’s directors and executive officers have interests in the merger, including financial interests, that may be different from, or in addition to, the interests of the other Bancorp Financial stockholders generally. The Bancorp Financial board of directors was aware of and considered these interests during its deliberations on the merits of the merger and in recommending to Bancorp Financial stockholders that they vote to approve the merger proposal and thereby approve the transactions contemplated by the merger agreement, including the merger.

For a more complete description of these interests, see “The Merger — Interests of Bancorp Financial Directors and Executive Officers in the Merger” beginning on page 56.

Board of Directors and Executive Officers of the Combined Company and the Combined Bank (page 58)

The merger agreement provides that, effective immediately after the effective time of the merger, the boards of directors of Old Second and Old Second National Bank will be increased in size by one and two, respectively, and Darin Campbell (as to each of Old Second and Old Second National Bank) and Jill Voss (as to Old Second National Bank), current members of the board of directors of Bancorp Financial or