Darin Patrick Campbell - 18 Feb 2026 Form 4 Insider Report for OLD SECOND BANCORP INC (OSBC)

Role: President, Powersports Lending, Director
Signature: /s/ Shirley Cantrell, Attorney-in-Fact
Issuer symbol: OSBC
Transactions as of: 18 Feb 2026
Net transactions value: -$732,900
Form type: 4
Filing time: 19 Feb 2026, 17:14:46 UTC
Previous filing: 24 Feb 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Campbell Darin Patrick	President, Powersports Lending, Director	37 S. RIVER ST., AURORA	/s/ Shirley Cantrell, Attorney-in-Fact	19 Feb 2026	0002074132

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	OSBC	Old Second Bancorp, Inc. Common Stock	Sale	$732,900	-35,000	-11%	$20.94	274,589	18 Feb 2026	Direct
holding	OSBC	Old second Bancorp Inc., Common Stock						0	18 Feb 2026	IRA	F1

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	The 31,159 shares reported in a prior Form 4 were disposed of on October 31, 2025 and were previously reported as such. Those shares were inadvertently included again in the prior filing due to a data import error. This From 4 corrects that error and reflects a zero (0) balance of shares.