Old Second Bancorp, Inc.
Old Second Bancorp, Inc. (OSBC) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · OSBC · as of Sep 30, 2025
Ownership Breakdown
200
Institutional Holders
▲ 16 vs Q2
$624.93M
Total Inst. Value
▲ $45.50M vs Q2
51.43M
Shares Outstanding
freeFloat 79.42%
36.15M
13F Shares Held
▲ 3.50M vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
OSBC largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
BLACKROCK, INC. state commercial banks | 3.82M | 8.49% | 8.49% | $65.99B | Nov 12, 2025 | ▲ 316.2K |
VANGUARD GROUP INC state commercial banks | 3.27M | 7.27% | 7.27% | $56.52B | Nov 7, 2025 | ▲ 553.2K |
DIMENSIONAL FUND ADVISORS LP state commercial banks | 2.20M | 4.90% | 4.90% | $38.11B | Nov 12, 2025 | ▲ 86.4K |
FJ CAPITAL MANAGEMENT LLC state commercial banks | 1.92M | 4.27% | 4.27% | $33.19B | Nov 14, 2025 | ▲ 82.6K |
GOLDMAN SACHS GROUP INC state commercial banks | 1.56M | 3.47% | 3.47% | $26.94B | Nov 14, 2025 | ▲ 163.4K |
DAVIS ASSET MANAGEMENT, L.P. state commercial banks | 1.50M | 3.34% | 3.34% | $25.93B | Nov 14, 2025 | ▲ 115.5K |
AMERICAN CENTURY COMPANIES INC state commercial banks | 1.39M | 3.09% | 3.09% | $23.99B | Nov 12, 2025 | ▲ 160.4K |
STATE STREET CORP state commercial banks | 1.37M | 3.04% | 3.04% | $23.64B | Nov 14, 2025 | ▲ 61.9K |
GEODE CAPITAL MANAGEMENT, LLC state commercial banks | 1.36M | 3.03% | 3.03% | $23.57B | Nov 12, 2025 | ▲ 211.8K |
KENNEDY CAPITAL MANAGEMENT LLC state commercial banks | 1.09M | 2.43% | 2.43% | $18.90B | Nov 13, 2025 | ▲ 96.3K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
31
Increased
+3.51M shares2
New Positions
first time holders13
Decreased
−409.8K shares0
Sold Out
fully exitedNet shares change (top 50)
+3.10M
+3.51M / −409.8K
Net new holders
+20
2 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
OSBC insider trading · insider activity
Source: SEC Form 4
Insiders have been primarily selling shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
1
Buy transactions
4
Sell transactions
0.25
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
COLLINS GARY S VICE CHAIRMAN | May 22, 2026 | Sale | 5,120 | $21.12 | $108.1K | 58.1K | Form 4 ↗ |
COLLINS GARY S VICE CHAIRMAN | May 21, 2026 | Sale | 10,000 | $21.12 | $211.2K | 63.3K | Form 4 ↗ |
Lyons Billy J Jr. director | May 11, 2026 | Purchase | 24 | $20.90 | $501.6 | 20.1K | Form 4 ↗ |
Pilmer Donald EVP | May 11, 2026 | Sale | 25,000 | $20.75 | $518.8K | 48.1K | Form 4 ↗ |
COLLINS GARY S VICE CHAIRMAN | May 8, 2026 | Sale | 5,000 | $21.23 | $106.1K | 73.3K | Form 4 ↗ |
COLLINS GARY S VICE CHAIRMAN | May 8, 2026 | Sale | 10,000 | $21.24 | $212.4K | 30.1K | Form 4 ↗ |
ADAMS BRADLEY S. CFO & COO | Mar 31, 2026 | J-Other | 35 | — | — | 10.2K | Form 4 ↗ |
COLLINS GARY S VICE CHAIRMAN | Mar 31, 2026 | J-Other | 253 | — | — | 7.1K | Form 4 ↗ |
Pilmer Donald EVP | Mar 31, 2026 | J-Other | 13 | — | — | 4.0K | Form 4 ↗ |
Pilmer Donald EVP | Mar 31, 2026 | J-Other | 1 | — | — | 183 | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
Old Second Bancorp, Inc. (OSBC) is primarily owned by institutional investors, who hold approximately 70.3% of total shares outstanding. Company insiders own approximately 20.58%, while retail and public investors account for the remaining 9.13%.
The largest institutional shareholder of Old Second Bancorp, Inc. is BLACKROCK, INC., holding approximately 3.82 million shares — equal to 8.49% of outstanding shares — as of September 30, 2025.
A total of 200 institutional investors currently hold OSBC stock, with a combined institutional value of approximately $624,929,111 as of the most recent 13F filing period.
Frequently asked questions
OSBC ownershipOld Second Bancorp, Inc. (OSBC) is primarily owned by institutional investors, who hold approximately 70.3% of shares. The largest shareholder is BLACKROCK, INC. with a 8.49% stake. Company insiders hold 20.58%. Data sourced from SEC Form 13F as of September 30, 2025.