Jill E. York - 21 Feb 2026 Form 4/A - Amendment Insider Report for OLD SECOND BANCORP INC (OSBC)

Reporting relationship: Director
Issuer ticker: OSBC
Reported as of: 21 Feb 2026
Net transaction value: $0
SEC form: 4/A - Amendment
Accepted by SEC: 21 Oct 2026, 15:57:10 UTC
Original report date: 24 Feb 2026
Prior SEC filing: 24 Feb 2026
Source filing: View source filing
Reporting owner signature: /s/ Shirley Cantrell, Attorney-in-Fact

Filing notes and source

Key filing fact

Jill E. York filed Form 4/A - Amendment for OLD SECOND BANCORP INC (OSBC) on 21 Oct 2026.

Key facts

This page summarizes Jill E. York's Form 4/A - Amendment filing for OLD SECOND BANCORP INC (OSBC).
2 reported transactions and 0 derivative rows are listed below.
Accepted by SEC: 21 Oct 2026, 15:57.

Change

Previous filing in this sequence was filed on 24 Feb 2026.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4/A - Amendment disclosures.

View source filing

Reporting Owners (1)

CIK 0001244438 Primary reporting owner

YORK JILL E

Relationship: Director
Address: C/O MB FINANCIAL INC, 6111 NORTH RIVER ROAD, ROSEMONT
Signature: /s/ Shirley Cantrell, Attorney-in-Fact
Signature date: 21 Oct 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

OSBC transaction

Restricted Stock Units

Other

Transaction value
Shares: -3,077
Change %: -23%
Price: $0.000000^*
Shares after: 10,595
Date: 21 Feb 2026
Ownership: Direct
Footnotes: F1

OSBC transaction

Old Second Bancorp, Inc. Common Stock

Other

Transaction value
Shares: +3,077
Change %
Price: $0.000000^*
Shares after: 3,077
Date: 21 Feb 2026
Ownership: Direct
Footnotes: F1

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 1 footnote

Footnote F1

Represents the settlement upon vesting of 3,077 restricted stock units into an equal number of shares of common stock. No shares were sold or withheld to satisfy taxes. This amendment corrects the original Form 4, which incorrectly reported the settlement using transaction code F.