# EDGAR Filing Document

**Accession Number:** 0000357173
**File Stem:** 0000357173-25-000079
**Filing Date:** 2025-9
**Character Count:** 6522
**Document Hash:** b11c51c2b2b909b1756bf81f6cb45e97
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000357173-25-000079.hdr.sgml**: 20250915

**ACCESSION NUMBER**: 0000357173-25-000079

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 13

**CONFORMED PERIOD OF REPORT**: 20250914

**ITEM INFORMATION**: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

**FILED AS OF DATE**: 20250915

**DATE AS OF CHANGE**: 20250915

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** OLD SECOND BANCORP INC
- **CENTRAL INDEX KEY:** 0000357173
- **STANDARD INDUSTRIAL CLASSIFICATION:** STATE COMMERCIAL BANKS [6022]
- **ORGANIZATION NAME:** 02 Finance
- **EIN:** 363143493
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 000-10537
- **FILM NUMBER:** 251313553

**BUSINESS ADDRESS:**
- **STREET 1:** 37 S RIVER ST
- **CITY:** AURORA
- **STATE:** IL
- **ZIP:** 60507
- **BUSINESS PHONE:** 6308920202

**MAIL ADDRESS:**
- **STREET 1:** 37 SOUTH RIVER STREET
- **CITY:** AURORA
- **STATE:** IL
- **ZIP:** 60507

?xml version='1.0' encoding='ASCII'? Old Second Bancorp, Inc

I

**United States**

**Securities And Exchange Commission**

**Washington, D.C. 20549**

**FORM 8-K**

**Current Report**

#### Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
Date of Report (Date of earliest event reported): **September 14, 2025**

![Graphic](tmb-20250914x8k001.jpg)

(Exact name of registrant as specified in its charter)

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| | | |
|:---|:---|:---|
| &nbsp;&nbsp;**Delaware** | &nbsp;&nbsp;**000-10537** | &nbsp;&nbsp;**36-3143493** |
| &nbsp;&nbsp;(State or other jurisdiction of incorporation) | &nbsp;&nbsp;(Commission File Number) | &nbsp;&nbsp;(I.R.S. Employer Identification No.) |

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**37 South River StreetAurora, Illinois 60507**(Address of principal executive offices) (Zip code)

#### (630) 892-0202 (Registrant's telephone number, including area code)
**N/A**

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (*see* General Instruction A.2. below):

**☐** Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

**☐** Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

**☐** Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

**☐** Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

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| | | |
|:---|:---|:---|
| **Title of each class** | **Trading Symbol(s)** | **Name of each exchange on which registered** |
| Common Stock | OSBC | The Nasdaq Stock Market |

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Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 under the Securities Act (17 CFR 230.405) or Rule 12b-2 under the Exchange Act (17 CFR 240.12b-2).

Emerging growth company **☐**

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. **☐**

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|:---|:---|
| **Item 5.02** | **Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.** |

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Effective September 14, 2025, John Ladowicz, a member of the Board of Directors (the "Board") of Old Second Bancorp, Inc. (the "Company"), resigned from the Board. Mr. Ladowicz submitted his resignation in accordance with the Company's Director Resignation Policy, which requires that any person serving as a director submit his or her resignation as a director upon attaining the age of 73 during his or her tenure. As such, Mr. Ladowicz's resignation is not the result of any disagreement with the Company. Mr. Ladowicz served on the Audit Committee, the Compensation Committee, the Nominating and Corporate Governance Committee, the Loan Committee, and the Risk and Insurance Committee. He has been a valuable Board member since 2008, and the Company appreciates his contributions during his tenure.

The Company does not anticipate immediately filling the vacancy on the Board caused by Mr. Ladowicz's resignation and will reduce the size of the Board by one member. Following a recommendation from the Nominating and Corporate Governance Committee, the Board's intent is to maintain the Board classes to be as nearly equal in number as possible. Accordingly, the Board realigned its Class I, II and III directors at its regularly scheduled meeting in February 2025, anticipating potential director retirements during 2025, including Mr. Ladowicz's retirement.

**Cautionary Statement Regarding Forward Looking Statements**

Statements included in this current report which are not historical in nature are intended to be, and are hereby identified as, forward looking statements for purposes of the safe harbor provided by Section 21E of the Securities Exchange Act of 1934. Forward looking statements generally include words such as "expects," "anticipates," "intends," "estimates," and other similar expressions. The Company cautions readers that forward looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from anticipated results. Such risks and uncertainties, include, among others, factors disclosed in the Company's 2024 Annual Report on Form 10-K filed March 6, 2025 or in its subsequent filings with the U.S. Securities and Exchange Commission, any of which could cause actual results to differ materially from future results expressed or implied by such forward looking statements.

**Signature**

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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| | | |
|:---|:---|:---|
|  | **OLD SECOND BANCORP, INC.** | **OLD SECOND BANCORP, INC.** |
| Dated: September 15, 2025 | By: | /s/ Bradley S. Adams |
|  |  | Bradley S. Adams |
|  |  | Executive Vice President,  |
|  |  | Chief Operating Officer, and |
|  |  | Chief Financial Officer |

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