# Old Second Bancorp Inc: filings

OSBC · Nasdaq · CIK 357173 · [Financials](/sectors/financials.md) · fiscal year ends Dec 31

Pages: [Overview](/companies/osbc.md) · [Financials](/companies/osbc/financials.md) · [Filings](/companies/osbc/filings.md) · [Insiders](/companies/osbc/insiders.md)

## Reports and events: 419 filings

Newest first, by EDGAR acceptance time (Eastern). Filter with ?form= one of: `periodic`, `8-K`, `10-K`, `10-Q`, `4`, `proxy`, `13dg`, `all`, or any form this company filed (4 801, 8-K 314, 10-Q 53, SC 13G/A 31, 4/A 28, DEF 14A 19, 10-K 18, 11-K 18, 3 16, CORRESP 15, 144 13, SC 13G 12, UPLOAD 12, EFFECT 8, 8-K/A 7, PRE 14A 7, 425 6, S-3 6, ARS 4, DEFA14A 4, S-8 4, 10-K/A 3, 424B3 3, S-1/A 3, 424B5 2, 8-A12G/A 2, FWP 2, S-3/A 2, S-4 2, S-4/A 2, SCHEDULE 13G/A 2, 10-Q/A 1, 144/A 1, 15-12G 1, 25-NSE 1, 424B4 1, D 1, S-1 1, S-3ASR 1, SCHEDULE 13G 1).

| Filed | Accepted | Form | What it is | Accession |
| --- | --- | --- | --- | --- |
| 2026-10-21 | 16:05 ET | [8-K](/filings/0000357173-26-000057.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0000357173-26-000057 |
| 2026-10-20 | 11:00 ET | [8-K](/filings/0000357173-26-000055.md) | 8.01 Other events | 0000357173-26-000055 |
| 2026-10-19 | 16:15 ET | [8-K](/filings/0000357173-26-000052.md) | 5.02 Departure or appointment of officers or directors | 0000357173-26-000052 |
| 2026-10-01 | 11:00 ET | [8-K](/filings/0000357173-26-000050.md) | 8.01 Other events | 0000357173-26-000050 |
| 2026-08-06 | 12:01 ET | [10-Q](/filings/0000357173-26-000045.md) | Quarterly report, period 2026-06-30 | 0000357173-26-000045 |
| 2026-07-22 | 16:05 ET | [8-K](/filings/0000357173-26-000042.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0000357173-26-000042 |
| 2026-07-21 | 11:00 ET | [8-K](/filings/0000357173-26-000039.md) | 8.01 Other events | 0000357173-26-000039 |
| 2026-07-08 | 11:00 ET | [8-K](/filings/0000357173-26-000037.md) | 5.02 Departure or appointment of officers or directors | 0000357173-26-000037 |
| 2026-07-01 | 11:00 ET | [8-K](/filings/0000357173-26-000035.md) | 8.01 Other events | 0000357173-26-000035 |
| 2026-06-25 | 11:00 ET | [8-K](/filings/0000357173-26-000030.md) | 8.01 Other events | 0000357173-26-000030 |
| 2026-06-09 | 11:00 ET | [8-K](/filings/0000357173-26-000028.md) | 5.02 Departure or appointment of officers or directors | 0000357173-26-000028 |
| 2026-05-20 | 10:30 ET | [8-K](/filings/0000357173-26-000026.md) | 5.07 Shareholder vote results | 0000357173-26-000026 |
| 2026-05-19 | 09:50 ET | [8-K](/filings/0000357173-26-000024.md) | 7.01 Regulation FD disclosure; 9.01 Financial statements and exhibits | 0000357173-26-000024 |
| 2026-05-07 | 15:01 ET | [10-Q](/filings/0000357173-26-000022.md) | Quarterly report, period 2026-03-31 | 0000357173-26-000022 |
| 2026-04-22 | 16:05 ET | [8-K](/filings/0000357173-26-000020.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0000357173-26-000020 |
| 2026-04-21 | 10:30 ET | [8-K](/filings/0000357173-26-000018.md) | 8.01 Other events | 0000357173-26-000018 |
| 2026-04-06 | 11:15 ET | [DEF 14A](/filings/0001104659-26-039829.md) | Proxy statement, period 2026-05-19 | 0001104659-26-039829 |
| 2026-04-01 | 11:00 ET | [8-K](/filings/0000357173-26-000016.md) | 8.01 Other events | 0000357173-26-000016 |
| 2026-03-04 | 11:30 ET | [8-K](/filings/0000357173-26-000014.md) | 8.01 Other events | 0000357173-26-000014 |
| 2026-02-26 | 14:30 ET | [10-K](/filings/0001104659-26-020393.md) | Annual report, period 2025-12-31 | 0001104659-26-020393 |
| 2026-01-29 | 12:30 ET | [8-K](/filings/0000357173-26-000012.md) | 8.01 Other events | 0000357173-26-000012 |
| 2026-01-21 | 16:05 ET | [8-K](/filings/0000357173-26-000010.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0000357173-26-000010 |
| 2026-01-20 | 11:30 ET | [8-K](/filings/0000357173-26-000007.md) | 8.01 Other events | 0000357173-26-000007 |
| 2026-01-02 | 14:15 ET | [8-K](/filings/0000357173-26-000005.md) | 8.01 Other events | 0000357173-26-000005 |
| 2025-11-06 | 16:13 ET | [10-Q](/filings/0000357173-25-000091.md) | Quarterly report, period 2025-09-30 | 0000357173-25-000091 |
| 2025-10-22 | 16:05 ET | [8-K](/filings/0000357173-25-000088.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0000357173-25-000088 |
| 2025-10-21 | 10:30 ET | [8-K](/filings/0000357173-25-000086.md) | 8.01 Other events | 0000357173-25-000086 |
| 2025-10-01 | 11:30 ET | [8-K](/filings/0000357173-25-000084.md) | 8.01 Other events | 0000357173-25-000084 |
| 2025-09-17 | 16:00 ET | [8-K/A](/filings/0000357173-25-000082.md) | 9.01 Financial statements and exhibits | 0000357173-25-000082 |
| 2025-09-15 | 11:00 ET | [8-K](/filings/0000357173-25-000079.md) | 5.02 Departure or appointment of officers or directors | 0000357173-25-000079 |
| 2025-08-07 | 15:55 ET | [10-Q](/filings/0000357173-25-000076.md) | Quarterly report, period 2025-06-30 | 0000357173-25-000076 |
| 2025-07-23 | 16:05 ET | [8-K](/filings/0000357173-25-000073.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0000357173-25-000073 |
| 2025-07-15 | 11:00 ET | [8-K](/filings/0000357173-25-000071.md) | 8.01 Other events | 0000357173-25-000071 |
| 2025-07-02 | 13:00 ET | [8-K](/filings/0000357173-25-000069.md) | 8.01 Other events | 0000357173-25-000069 |
| 2025-07-01 | 08:00 ET | [8-K](/filings/0000357173-25-000066.md) | 2.01 Completion of an acquisition or disposition; 5.02 Departure or appointment of officers or directors; 8.01 Other events; 9.01 Financial statements and exhibits | 0000357173-25-000066 |
| 2025-06-18 | 16:06 ET | [8-K](/filings/0000357173-25-000060.md) | 7.01 Regulation FD disclosure | 0000357173-25-000060 |
| 2025-06-03 | 12:45 ET | [8-K/A](/filings/0000357173-25-000055.md) | 5.07 Shareholder vote results | 0000357173-25-000055 |
| 2025-05-28 | 11:00 ET | [8-K](/filings/0000357173-25-000048.md) | 5.03 Amendment to articles or bylaws; 9.01 Financial statements and exhibits | 0000357173-25-000048 |
| 2025-05-22 | 14:45 ET | [8-K](/filings/0000357173-25-000044.md) | 8.01 Other events; 9.01 Financial statements and exhibits | 0000357173-25-000044 |
| 2025-05-20 | 15:15 ET | [8-K](/filings/0000357173-25-000041.md) | 5.07 Shareholder vote results | 0000357173-25-000041 |
| 2025-05-20 | 09:50 ET | [8-K](/filings/0000357173-25-000038.md) | 7.01 Regulation FD disclosure; 9.01 Financial statements and exhibits | 0000357173-25-000038 |
| 2025-05-09 | 12:00 ET | [10-Q](/filings/0000357173-25-000035.md) | Quarterly report, period 2025-03-31 | 0000357173-25-000035 |
| 2025-04-23 | 16:05 ET | [8-K](/filings/0000357173-25-000032.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0000357173-25-000032 |
| 2025-04-18 | 12:00 ET | [DEF 14A](/filings/0001558370-25-005000.md) | Proxy statement, period 2025-05-20 | 0001558370-25-005000 |
| 2025-04-15 | 11:30 ET | [8-K](/filings/0000357173-25-000029.md) | 8.01 Other events | 0000357173-25-000029 |
| 2025-04-01 | 10:30 ET | [8-K](/filings/0000357173-25-000026.md) | 8.01 Other events | 0000357173-25-000026 |
| 2025-03-06 | 15:46 ET | [10-K](/filings/0001558370-25-002383.md) | Annual report, period 2024-12-31 | 0001558370-25-002383 |
| 2025-02-25 | 07:00 ET | [8-K](/filings/0000357173-25-000018.md) | 1.01 Entry into a material agreement; 8.01 Other events; 9.01 Financial statements and exhibits | 0000357173-25-000018 |
| 2025-01-22 | 16:05 ET | [8-K](/filings/0000357173-25-000013.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0000357173-25-000013 |
| 2025-01-21 | 11:00 ET | [8-K](/filings/0000357173-25-000008.md) | 8.01 Other events | 0000357173-25-000008 |

Page 1 of 9. [Older](/companies/osbc/filings.md?page=2)
Source: SEC EDGAR, the company’s filing index. Last ingested by Listed: Oct 30, 2026, 12:40 ET. No prices; not investment advice.