James Eccher - 02 Mar 2026 Form 4 Insider Report for OLD SECOND BANCORP INC (OSBC)

Role: CHAIRMAN AND CEO, Director
Signature: /s/ Shirley Cantrell, Attorney-in-Fact
Issuer symbol: OSBC
Transactions as of: 02 Mar 2026
Net transactions value: $0
Form type: 4
Filing time: 04 Mar 2026, 14:38:32 UTC
Previous filing: 24 Feb 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Eccher James	CHAIRMAN AND CEO, Director	37 S. RIVER ST., AURORA	/s/ Shirley Cantrell, Attorney-in-Fact	04 Mar 2026	0001314109

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	OSBC	Old Second Bancorp, Inc. Common Stock	Award		+43,818	+13%	$0.000000^*	391,237	02 Mar 2026	Direct	F1
transaction	OSBC	Old Second Bancorp, Inc. Common Stock	Tax liability		-12,838	-3.3%	$19.91^*	378,399	02 Mar 2026	Direct	F2, F3
holding	OSBC	Old Second Bancorp, Inc. Common Stock						33,018	02 Mar 2026	By 401-K
holding	OSBC	Old Second Bancorp, Inc. Common Stock						6,335	02 Mar 2026	By Profit Sharing
holding	OSBC	Restricted Stock Units						188,252	02 Mar 2026	Direct

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

Explanation of Responses:

Id	Content
F1	Shares delivered to the reporting person pursuant to vesting of performance-based restricted stock units granted under the Old Second Bancorp, Inc. 2019 Equity Incentive Plan, as Amended and Restated and vested upon achievement of performance goals for the applicable performance period. The reporting person reported an acquisition of 25,038 on Form 4 filed February 21, 2023, which represented the number of shares that would be delivered if target performance was achieved during the performance period. Actual performance exceeded the target performance for the performance period which resulted in an additional grant of 18,780 shares.
F2	Represents shares withheld by the issuer to satisfy applicable tax withholding obligations in connection with the vesting of 43,818 previously reported performance-based restricted stock units, the remaining shares of which were issued and added to the reporting person's common stock holdings.
F3	Included in this total are 30,980 shares held in the reporting person's name outright; 347,271 shares held with a brokerage firm and 148 shares held jointly with spouse.