Old Second (OSBC) EVP gets 5,912 RSUs, 894 shares withheld

Rhea-AI Filing Summary

Old Second Bancorp EVP Richard A. Gartelmann Jr. reported equity-compensation activity involving restricted stock units tied to the company’s common stock. He received a grant of 5,912 restricted stock units, split evenly between time-based and performance-based awards.

On the same award, 894 shares were withheld at $20.57 per share to cover tax obligations when 2,585 previously reported time-based units vested, with the remaining vested shares added to his common stock holdings. Following these transactions, he holds company stock both directly and through a 401(k).

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Gartelmann Richard A JR

(Last) (First) (Middle)

37 S. RIVER ST.

(Street)

AURORA IL 60506

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
OLD SECOND BANCORP INC [ OSBC ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP

3. Date of Earliest Transaction (Month/Day/Year)
02/17/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Restricted Stock Units	02/17/2026		A		5,912(1)	A	$0	26,464	D
Restricted Stock Units	02/21/2026		F		894(2)	D	$20.57	23,879	D
Old Second Bancorp, Inc. Common Stock								1,691(3)	D
Old Second Bancorp, Inc. Common Stock								24,874	D
Old Second Bancorp, Inc. Common Stock								12,563	I	By 401-K

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 5,912 restricted stock units on the date of the grant, 2,956 of which are time-based restricted stock units that vest on the third anniversary of the grant date, and 2,956 of which are performance-based restricted stock units that may vest and convert to shares within a range from 0% to 175% of the underlying performance-based restricted stock units originally awarded, depending on our compensation committee approved performance metrics. Vested shares, if any, will be delivered to the reporting person in 3 to 5 business days from the date of vesting.

2. Represents shares withheld by the issuer to satisfy applicable tax withholding obligations in connection with the vesting of 2,585 previously reported time-based restricted stock units, the remaining shares of which were issued and added to the reporting person's common stock holdings.

3. These shares are held in Mr. Gartelmann's name outright.

	/s/ Shirley Cantrell, Attorney-in-Fact	02/24/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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FAQ

What did Old Second Bancorp (OSBC) disclose about Richard Gartelmann’s Form 4?

Old Second Bancorp reported EVP Richard A. Gartelmann Jr. received 5,912 restricted stock units and had 894 shares withheld for taxes. The filing reflects routine equity compensation and tax withholding, not an open-market stock purchase or sale by the executive.

How many restricted stock units did OSBC’s EVP receive in this Form 4 filing?

Richard Gartelmann Jr. was granted 5,912 restricted stock units. Half are time-based units vesting on the third anniversary of the grant date, while the other half are performance-based units that may vest from 0% to 175% depending on compensation committee-approved performance metrics.

What are the vesting terms of the new OSBC restricted stock unit grant?

The 5,912 restricted stock units are split into 2,956 time-based and 2,956 performance-based units. Time-based units vest on the third anniversary of grant. Performance-based units can vest between 0% and 175% of the original amount, depending on approved performance metrics and subsequent outcomes.

Why were 894 OSBC shares withheld in Richard Gartelmann’s Form 4?

The 894 shares were withheld to satisfy tax withholding obligations when 2,585 previously reported time-based restricted stock units vested. The remaining vested shares were issued as common stock and added to Richard Gartelmann Jr.’s holdings instead of being sold in the market.

Does this OSBC Form 4 show Richard Gartelmann selling stock on the market?

No, the disposition involves shares withheld for taxes, not an open-market sale. Code F reflects payment of tax liability by delivering securities when restricted stock units vest, while the rest of the vested shares increased his direct common stock holdings at Old Second Bancorp.

How are Old Second Bancorp (OSBC) shares held by Richard Gartelmann after these transactions?

After the reported transactions, Richard Gartelmann Jr. holds Old Second Bancorp common stock directly in his name and indirectly through a 401(k). The Form 4 notes certain shares are held outright, while a separate portion is specifically labeled as being held by a 401-K plan.