Company: OSBC
Filing Date: 2025-04-23
Form Type: S-4
Source: 0001104659-25-037832
Chunk: 99

Company: OLD SECOND BANCORP INC
Filing Date: 2025-04-23
Form: S-4
Chunk 99
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, prior to the effective time of the merger, the number of outstanding shares of Old Second common stock are changed into or exchanged for a different number or kind of shares or securities as a result of a stock dividend, subdivision, reclassification, recapitalization, split, combination or exchange of shares an appropriate adjustment will be made to the exchange ratio to provide the holders of Bancorp Financial common stock the same economic effect as contemplated by the merger agreement prior to such event.

#### Fractional Shares
Old Second will not issue any fractional shares of Old Second common stock in the merger. Instead, a Bancorp Financial stockholder who otherwise would have received a fraction of a share of Old Second

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common stock will receive an amount in cash, rounded up to the nearest cent (without interest), equal to such fraction of a share (rounded to the nearest thousandth when expressed as a decimal form) multiplied by the average closing price of Old Second common stock as quoted on NASDAQ, during the five full trading days ending on the trading day prior to the date the merger is consummated.

### Treatment of Bancorp Financial Equity Awards
At the effective time of the merger, each restricted stock unit award granted under Bancorp Financial’s equity plan outstanding as of the effective time will become fully vested and terminated and converted into the right to receive from Old Second, within ten business days following the effective time, (i) the cash consideration and (ii) the stock consideration, with respect to each share of Bancorp Financial common stock subject to such restricted stock award (or portion thereof) immediately prior to the effective time. Old Second will deduct, withhold, or require the holder of the restricted stock award to remit to Old Second, an amount sufficient to satisfy all amounts required to be withheld under applicable tax laws after first applying such withholding amount from the cash consideration and then providing the opportunity to such holder to elect to satisfy any remaining withholding amount (in whole or in part) by having Old Second withhold from the stock consideration the number of shares of Old Second common stock with a value equal to such withholding amount.

#### Governing Documents
Old Second’s certificate of incorporation and bylaws in effect immediately prior to the effective time of the merger will be the certificate of incorporation and bylaws of the combined company until otherwise duly amended or repealed.

#### Closing and Effective Time of the Merger
The merger will be completed only if all conditions to the merger discussed in this proxy statement/ prospectus and set forth