# EDGAR Filing Document

**Accession Number:** 0000357173
**File Stem:** 0001104659-26-039838
**Filing Date:** 2026-4
**Character Count:** 1102
**Document Hash:** 4da44e69771805ecf0cbcaa578927544
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-26-039838.hdr.sgml**: 20260406

**ACCESSION NUMBER**: 0001104659-26-039838

**CONFORMED SUBMISSION TYPE**: ARS

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20251231

**FILED AS OF DATE**: 20260406

**DATE AS OF CHANGE**: 20260406

**EFFECTIVENESS DATE**: 20260406

**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:** ARS
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 000-10537
- **FILM NUMBER:** 26840032

**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

### Attached PDF Documents

**Attachment 1:** `tm267618d2_ars.pdf`

_No text found in this document._