Company: OSBC
Filing Date: 2025-09-17
Form Type: 8-K/A
Source: 0000357173-25-000082
Chunk: 1

Company: OLD SECOND BANCORP INC
Filing Date: 2025-09-17
Form: 8-K/A
Chunk 1
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 of the Exchange Act. ☐

Explanatory Note

The pro forma financial information included in this Current Report on Form 8-K/A has been presented for informational purposes only, as required by Form 8-K. It does not purport to represent the actual results of operations that Old Second and Bancorp Financial would have achieved had the companies been combined during the periods presented in the pro forma financial information and is not intended to project the future results of operations that the combined company may achieve after completion of the Merger. Except as described above, all other information in the Initial Filing remains unchanged.

Item 9.01 Financial Statements and Exhibits

(a) Financial Statements of Businesses Acquired.

The audited consolidated financial statements of Bancorp Financial, Inc. as of December 31, 2024 and 2023, and for each of the years in the two-year period ended December 31, 2024, and related notes, are hereby incorporated by reference to Exhibit 99.1 hereto.

The unaudited consolidated financial statements of Bancorp Financial, Inc. as of June 30, 2025 and 2024, and for the six-month periods ended June 30, 2025 and 2024, and related notes, are hereby incorporated by reference to Exhibit 99.2 hereto.

(b) Pro Forma Financial Information.

The unaudited pro forma condensed combined balance sheet as of December 31, 2024 and the unaudited pro forma condensed combined income statement for the year ended December 31, 2024, are hereby incorporated by reference to Exhibit 99.3 hereto.

The unaudited pro forma condensed combined balance sheet as of June 30, 2025 and the unaudited pro forma condensed combined income statement for the six months ended June 30, 2025, are hereby incorporated by reference to Exhibit 99.4 hereto.

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(d) Exhibits.

| ​           | ​ | ​                                                                                                                                                                                                                                                                                                                                                                     |
| Exhibit No. | ​ | Description                                                                                                                                                                                                                                                                                                                                                           |
| 23.1        | ​ | Consent of RSM US LLP.                                                                                                                                                                                                                                                                                                                                                |
| ​           | ​ | ​                                                                                                                                                                                                                                                                                                                                                                     |
| 99.1        | ​ | Audited consolidated financial statements of Bancorp Financial, Inc. as of December 31, 2024 and 2023, and for each of the years in the two-year period ended December