Company: OSBC
Filing Date: 2025-04-23
Form Type: S-4
Source: 0001104659-25-037832
Chunk: 53

Company: OLD SECOND BANCORP INC
Filing Date: 2025-04-23
Form: S-4
Chunk 53
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 50% of the costs of soliciting proxies from Bancorp Financial stockholders, including the cost of mailing this proxy statement/ prospectus.

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In addition to solicitation of proxies by mail, proxies may be solicited by Bancorp Financial’s officers, directors and regular employees, without additional compensation, by personal interview, telephone, or other means of communication.

Bancorp Financial will make arrangements with brokerage houses, custodians, nominees, and fiduciaries to forward proxy solicitation materials to beneficial owners of Bancorp Financial common stock. Bancorp Financial may reimburse these intermediaries for their reasonable expenses incurred in forwarding the proxy materials. These costs will also be subject to the 50/50 cost-sharing arrangement with Old Second.

#### Assistance
If you need assistance in completing your proxy card, have questions regarding the Bancorp Financial special meeting or would like additional copies of this proxy statement/prospectus, please contact our Corporate Secretary, Mr. Michael Spaniak, at (630) 413-9580.

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### BANCORP FINANCIAL PROPOSALS

#### Proposal 1 — Adoption of the Merger Agreement
**As discussed elsewhere in this proxy statement/prospectus, Bancorp Financial stockholders are being asked to approve the merger proposal, which provides for the merger of Bancorp Financial with and into Old Second in accordance with the terms of the merger agreement. Under Delaware law, the approval of the merger agreement by the holders of a majority of the outstanding shares of Bancorp Financial common stock entitled to vote is required in order to complete the merger. If stockholders do not approve the merger proposal, the merger will not be completed.

Bancorp Financial stockholders may vote on the merger proposal by submitting a valid proxy or timely casting a vote via telephone or the Internet, as described above, in advance of the meeting. Stockholders are encouraged to carefully read this proxy statement/prospectus in its entirety, including the merger agreement, which is attached as Annex A, for a more detailed description of the terms and conditions of the merger and the other transactions contemplated by the merger agreement.

After careful consideration, the Bancorp Financial board of directors has unanimously determined that the merger agreement and the transactions contemplated thereby, including the merger, are advisable, fair to, and in the best interests of Bancorp Financial and its stockholders.

The Bancorp Financial board of directors