Company: OSBC
Filing Date: 2025-05-08
Form Type: 424B3
Source: 0001104659-25-046065
Chunk: 26

Company: OLD SECOND BANCORP INC
Filing Date: 2025-05-08
Form: 424B3
Chunk 26
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 the applicable appraisal statutes;

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the execution by Darin Campbell of the Old Second employment agreement and compensation and benefits assurance agreement (collectively, the “employment agreements”) in the forms attached to the merger agreement; and

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Bancorp Financial will have terminated its stockholders agreement prior to or as of the effective time of the merger.

Neither Bancorp Financial nor Old Second can be certain when, or if, the conditions to the merger will be satisfied or waived, or that the merger will be completed. For more information see “The Merger Agreement — Conditions to Complete the Merger” beginning on page 72.

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TABLE OF CONTENTS

#### Termination (page 73)
The merger agreement may be terminated prior to the effective time under the following circumstances:

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by mutual written agreement of Old Second or Bancorp Financial;

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by either Old Second or Bancorp Financial:

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if (i) any regulatory agency has denied a required regulatory approval and such denial has become final, has advised either party that it will not grant or intends to rescind or revoke a required regulatory approval, or has requested that either party withdraw (other than for technical reasons) an application for a required regulatory approval and not be permitted to resubmit within 60 days, or has indicated it would not accept a resubmission; provided, that the right to terminate is not available to a party whose breach caused or resulted in such action; or (ii) any law, order, injunction, decree, or other legal restraint permanently restraining, enjoining, prohibiting, or making illegal the consummation of the merger becomes final and nonappealable, provided the terminating party has used its reasonable best efforts to contest, appeal, and remove such restraint;

•

if the merger has not been consummated on or before December 31, 2025, or, if the only remaining condition to closing is the receipt of a required regulatory approval, then by March 31, 2026, which we refer to as the “termination date”; provided, that the right to terminate is not available to a party whose failure to perform its obligations under the merger agreement was the cause of the failure to close by such date; and

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if Bancorp Financial stockholders fail to approve the merger at the stockholders meeting or any adjournment or postponement thereof; provided, that Bancorp Financial may not terminate the agreement on this basis if it breached its non-solicitation and stockholder meeting obligations under the merger