OSBC

SEC source: 0001415889-25-020082 · form4-07212025_090707.xml · nonDerivative · entry 1

Campbell Darin Patrick · CIK 0002074132 · Director · President, Powersports Lending

10b5-1 filing: No plan indicated

Ownership: Indirect · IRA

Disclosed balance after: 57,565

F1 · shares: These shares were issuable pursuant to the merger of Bancorp Financial, Inc. with and into Old Second Bancorp, Inc., which became effective on July 1, 2025. The reporting person held 22,300 shares of Bancorp Financial, Inc., which pursuant to the merger agreement was converted into 57,565 shares of Old Second Bancorp, Inc. common stock. These shares are held in a custodial account in an IRA on behalf of the reporting person. The exchange of shares occurred on July 19, 2025.

SEC source: 0001415889-25-019407 · form4-07072025_080735.xml · nonDerivative · entry 2

Eccher James · CIK 0001314109 · Director · CHAIRMAN AND CEO

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K

Disclosed balance after: 32,759

F2 · balance_after: Of this total, 120 shares were allocated during the second quarter pursuant to the Old Second Employee Salary and Savings Plan. Information herein was provided by the plan trustee as of 6-30-25.

SEC source: 0001415889-25-019407 · form4-07072025_080735.xml · nonDerivative · entry 1

Eccher James · CIK 0001314109 · Director · CHAIRMAN AND CEO

10b5-1 filing: No plan indicated

Ownership: Indirect · By Profit Sharing

Disclosed balance after: 6,289

F1 · balance_after: Of this total, 22 shares were allocated during the second quarter pursuant to the Old Second Bancorp, Inc. Employee Profit Sharing Plan and Trust. Information herein was provided by the plan trustee as of 6-30-25.

SEC source: 0001415889-25-019405 · form4-07072025_080719.xml · nonDerivative · entry 1

ADAMS BRADLEY S. · CIK 0001598917 · CFO & COO

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-k Plan

Disclosed balance after: 10,050

F1 · balance_after: Of this total, 36 shares were allocated during the second quarter pursuant to the Old Second Bancorp, Inc. Employee Salary and Savings Plan. Information herein was provided by the Plan trustee as of 6-30-25.

SEC source: 0001415889-25-019402 · form4-07072025_080724.xml · nonDerivative · entry 2

Pilmer Donald · CIK 0001673321 · EVP

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K Plan

Disclosed balance after: 3,981

F2 · balance_after: Of this total, 15 shares were allocated during the second quarter pursuant to the Old Second Employee Salary and Savings Plan. Information herein was provided by the plan trustee as of 6-30-25.

SEC source: 0001415889-25-019402 · form4-07072025_080724.xml · nonDerivative · entry 1

Pilmer Donald · CIK 0001673321 · EVP

10b5-1 filing: No plan indicated

Ownership: Indirect · By Profit Sharing Plan

Disclosed balance after: 181

F1 · balance_after: Of this total, 1 share was allocated during the second quarter pursuant to the Old Second Profit Sharing Plan. Information herein was provided by the plan trustee as of 6-30-25.

SEC source: 0001415889-25-019400 · form4-07072025_080706.xml · nonDerivative · entry 1

COLLINS GARY S · CIK 0001184766 · Director · VICE CHAIRMAN

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K

Disclosed balance after: 6,703

F1 · balance_after: Of this total, 113 shares were allocated during the second quarter pursuant to the Old Second Employee Salary and Savings Plan. Information herein was provided by the plan trustee as of 6-30-25.

SEC source: 0001415889-25-019453 · form4-07082025_010729.xml · nonDerivative · entry 1

Gartelmann Richard A JR · CIK 0001840027 · EVP

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K

Disclosed balance after: 12,472

F1 · balance_after: Of this total, 47 shares were allocated during the second quarter pursuant to the Old Second Employee Salary and Savings Plan. Information herein was provided by the plan trustee as of 6-30-25.

SEC source: 0001415889-25-012091 · form4-05062025_070549.xml · nonDerivative · entry 2

Eccher James · CIK 0001314109 · Director · CHAIRMAN AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 329,896

F2 · shares: Shares were acquired by the reporting person upon distribution of a trust due to the death of a family member, in accordance with the terms of the trust.

F3 · balance_after: Included in this total are 148 shares held jointly with spouse. The remaining 329,748 shares are held in Trust for the reporting person.

SEC source: 0001415889-25-012091 · form4-05062025_070549.xml · nonDerivative · entry 1

Eccher James · CIK 0001314109 · Director · CHAIRMAN AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 326,368

F1 · shares: Shares were acquired by the reporting person upon distribution of a trust due to the death of a family member, in accordance with the terms of the trust.

SEC source: 0001415889-25-012077 · form4-05062025_040500.xml · nonDerivative · entry 1

Lyons Billy J Jr. · CIK 0001829064 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,921

SEC source: 0001415889-25-009419 · form4-04012025_090450.xml · nonDerivative · entry 1

ADAMS BRADLEY S. · CIK 0001598917 · CFO & COO

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-k Plan

Disclosed balance after: 10,014

F1 · balance_after: Of this total, 31 shares were allocated during the first quarter pursuant to the Old Second Bancorp, Inc. Employee Salary and Savings Plan. Information herein was provided by the plan trustee as of 3-31-25.

SEC source: 0001415889-25-009401 · form4-04012025_090412.xml · nonDerivative · entry 1

Pilmer Donald · CIK 0001673321 · EVP

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K Plan

Disclosed balance after: 3,966

F1 · balance_after: Of this total, 12 shares were allocated during the first quarter pursuant to the Old Second Bancorp, Inc. Employee Salary Savings Plan. Information herein was provided by the plan trustee as of 3-31-25.

SEC source: 0001415889-25-009394 · form4-04012025_090418.xml · nonDerivative · entry 2

Eccher James · CIK 0001314109 · Director · CHAIRMAN AND CEO

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K

Disclosed balance after: 32,639

F2 · balance_after: Of this total are 381 shares that were allocated during the first quarter pursuant to the Old Second Bancorp, Inc. Employee Salary and Savings Plan. Information herein was provided by the plan trustee as of 3-31-25.

SEC source: 0001415889-25-009394 · form4-04012025_090418.xml · nonDerivative · entry 1

Eccher James · CIK 0001314109 · Director · CHAIRMAN AND CEO

10b5-1 filing: No plan indicated

Ownership: Indirect · By Profit Sharing

Disclosed balance after: 6,267

F1 · balance_after: Of this total, 20 shares were allocated during the first quarter pursuant to the Old Second Bancorp, Inc. Employee Profit Sharing Plan and Trust. Information herein was provided by the plan trustee as of 3-31-25.

SEC source: 0001415889-25-009391 · form4-04012025_080428.xml · nonDerivative · entry 1

Gartelmann Richard A JR · CIK 0001840027 · EVP

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K

Disclosed balance after: 12,425

F1 · balance_after: Of this total, 248 shares were allocated during the first quarter pursuant to the Old Second Bancorp, Inc. Employee Salary and Savings Plan. Information herein was provided by the plan trustee as of 3-31-25.

SEC source: 0001415889-25-009389 · form4-04012025_080412.xml · nonDerivative · entry 1

COLLINS GARY S · CIK 0001184766 · Director · VICE CHAIRMAN

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K

Disclosed balance after: 6,590

F1 · balance_after: Of this total, 220 shares were allocated during the first quarter pursuant to the Old Second Employee Salary and Savings Plan. Information herein was provided by the plan trustee as of 3-31-25.

SEC source: 0001415889-25-008881 · form4-03252025_020348.xml · nonDerivative · entry 1

Gartelmann Richard A JR · CIK 0001840027 · EVP

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,552

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 2,724 restricted stock units on the date of grant, 1,362 of which are time-based restricted stock units that vest on the third anniversary of the grant date and 1,362 of which are performance-based restricted stock units that may vest and convert to shares within a range from 0% to 150% 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 within 3 to 5 business days from the date of vesting.

SEC source: 0001415889-25-007256 · form4-03062025_100323.xml · nonDerivative · entry 2

ADAMS BRADLEY S. · CIK 0001598917 · CFO & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 143,308

F2 · shares: Shares withheld for taxes upon settlement in shares of the performance-based restricted stock units previously granted to the reporting person.

F3 · balance_after: Included in this total are 75,300 shares held with a broker and 68,008 shares held by the reporting person jointly with spouse.

SEC source: 0001415889-25-007256 · form4-03062025_100323.xml · nonDerivative · entry 1

ADAMS BRADLEY S. · CIK 0001598917 · CFO & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 147,831

F1 · shares: 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 8,821 on Form 4 filed on February 15, 2022, 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 6,618 shares.

SEC source: 0001415889-25-007254 · form4-03062025_100329.xml · nonDerivative · entry 2

Eccher James · CIK 0001314109 · Director · CHAIRMAN AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 322,840

F2 · shares: Shares withheld for taxes upon settlement in shares of the performance-based restricted stock units previously granted to the reporting person.

F3 · balance_after: Included in this total are 301,337 shares held with a broker; 21,355 shares held outright in the reporting person's name and 148 shares held jointly with spouse.

SEC source: 0001415889-25-007254 · form4-03062025_100329.xml · nonDerivative · entry 1

Eccher James · CIK 0001314109 · Director · CHAIRMAN AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 331,688

F1 · shares: 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 17,258 on Form 4 filed on February 15, 2022, 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 12,945 shares.

SEC source: 0001415889-25-007252 · form4-03062025_100331.xml · nonDerivative · entry 2

COLLINS GARY S · CIK 0001184766 · Director · VICE CHAIRMAN

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 63,112

F3 · shares: Shares withheld for taxes upon the settlement in shares of the performance-based restricted stock units previously granted to the reporting person.

F4 · balance_after: Included in this total are 46,624 shares held with a broker and 16,488 shares held outright in the reporting person's name solely.

SEC source: 0001415889-25-007252 · form4-03062025_100331.xml · nonDerivative · entry 1

COLLINS GARY S · CIK 0001184766 · Director · VICE CHAIRMAN

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 67,559

F1 · shares: 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 8,673 on Form 4 filed on February 15, 2022, 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 6,507 shares.

F2 · balance_after: Included in this total are 46,624 shares held with a broker and 16,488 shares held outright in the reporting person's name solely.

SEC source: 0001415889-25-005064 · form4-02212025_090206.xml · nonDerivative · entry 1

Williams John JR · CIK 0001895832 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,551

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 3,190 restricted stock units on the date of the grant. These shares are time-based restricted stock units that vest on the third anniversary of the grant date.

SEC source: 0001415889-25-005061 · form4-02212025_090211.xml · nonDerivative · entry 1

Kotche Keith · CIK 0001896747 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,551

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 3,190 restricted stock units on the date of the grant. These shares are time-based restricted stock units that vest on the third anniversary of the grant date.

SEC source: 0001415889-25-005058 · form4-02212025_090202.xml · nonDerivative · entry 1

BONIFAS EDWARD · CIK 0001191044 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,551

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 3,190 restricted stock units on the date of the grant. These shares are time-based restricted stock units that vest on the third anniversary of the grant date.

SEC source: 0001415889-25-005052 · form4-02212025_090212.xml · nonDerivative · entry 1

YORK JILL E · CIK 0001244438 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,551

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 3,190 restricted stock units on the date of the grant. These shares are time-based restricted stock units that vest on the third anniversary of the grant date.

SEC source: 0001415889-25-005049 · form4-02212025_090226.xml · nonDerivative · entry 1

Temple Rocks Patti · CIK 0001655300 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,551

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 3,190 restricted stock units on the date of the grant. These shares are time-based restricted stock units that vest on the third anniversary of the grant date.

SEC source: 0001415889-25-005047 · form4-02212025_090227.xml · nonDerivative · entry 1

MCLEAN HUGH H · CIK 0001184764 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,551

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 3,190 restricted stock units on the date of the grant. These shares are time-based restricted stock units that vest on the third anniversary of the grant date.

SEC source: 0001415889-25-005045 · form4-02212025_090221.xml · nonDerivative · entry 1

Lyons Billy J Jr. · CIK 0001829064 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,551

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 3,190 restricted stock units on the date of the grant. These shares are time-based restricted stock units that vest on the third anniversary of the grant date.

SEC source: 0001415889-25-005043 · form4-02212025_090200.xml · nonDerivative · entry 1

Ladowicz John · CIK 0001424453 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,551

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 3,190 restricted stock units on the date of the grant. These shares are time-based restricted stock units that vest on the third anniversary of the grant date.

SEC source: 0001415889-25-005041 · form4-02212025_090240.xml · nonDerivative · entry 1

KLAESER DENNIS L · CIK 0001225765 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,551

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 3,190 restricted stock units on the date of the grant. These shares are time-based restricted stock units that vest on the third anniversary of the grant date.

SEC source: 0001415889-25-005037 · form4-02212025_090242.xml · nonDerivative · entry 1

ADAMS BRADLEY S. · CIK 0001598917 · CFO & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 86,265

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 26,316 restricted stock units on the date of the grant, 13,158 of which are time-based restricted stock units that vest on the third anniversary of the grant date, and 13,158 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.

F2 · balance_after: Of this total, 38,722 shares are Restricted Stock Units and 47,543 shares are Performance-based Restricted Stock Units.

SEC source: 0001415889-25-005039 · form4-02212025_090233.xml · nonDerivative · entry 1

Finn Barry · CIK 0001296986 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,551

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 3,190 restricted stock units on the date of the grant. These shares are time-based restricted stock units that vest on the third anniversary of the grant date.

SEC source: 0001415889-25-005033 · form4-02212025_080255.xml · nonDerivative · entry 1

Eccher James · CIK 0001314109 · Director · CHAIRMAN AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 201,576

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 57,154 restricted stock units on the date of the grant, 28,577 of which are time-based restricted stock units that vest on the third anniversary of the grant date, and 28,577 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.

F2 · balance_after: Of this total, 109,417 shares are performance-based restricted stock units and 92,159 shares are time-based restricted stock units.

SEC source: 0001415889-25-005029 · form4-02212025_080240.xml · nonDerivative · entry 1

Gartelmann Richard A JR · CIK 0001840027 · EVP

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17,828

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 5,508 restricted stock units on the date of the grant, 2,754 of which are time-based restricted stock units that vest on the third anniversary of the grant date, and 2,754 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.

F2 · balance_after: Of this total, 8,914 shares are performance-based restricted stock units and 8,914 are time-based restricted stock units.

SEC source: 0001415889-25-005031 · form4-02212025_080245.xml · nonDerivative · entry 1

COLLINS GARY S · CIK 0001184766 · Director · VICE CHAIRMAN

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 53,619

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 11,962 restricted stock units on the date of the grant, 5,981 of which are time-based restricted stock units that vest on the third anniversary of the grant date, and 5,981 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.

F2 · balance_after: Of this total, 31,146 shares are Performance-based Restricted Stock Units and 22,473 are time-based Restricted Stock Units.

SEC source: 0001415889-25-005027 · form4-02212025_080239.xml · nonDerivative · entry 1

Pilmer Donald · CIK 0001673321 · EVP

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 38,718

F1 · shares: Each restricted stock unit represents a contingent right to receive one share of common stock. The reporting person was granted 12,142 restricted stock units on the date of the grant, 6,071 of which are time-based restricted stock units that vest on the third anniversary of the grant date, and 6,071 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.

F2 · balance_after: Of this total, 19,359 shares are performance-based restricted stock units and 19,359 shares are time-based restricted stock units.

SEC source: 0001415889-25-003541 · form4-02112025_030232.xml · nonDerivative · entry 1

Lyons Billy J Jr. · CIK 0001829064 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 13,815

F1 · balance_after: Of this total, 5,273 shares are held in Mr. Lyon's name outright and 8,542 shares are held in a brokerage account for Mr. Lyons.

SEC source: 0001415889-25-000064 · form4-01022025_070138.xml · nonDerivative · entry 1

ADAMS BRADLEY S. · CIK 0001598917 · CFO

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-k Plan

Disclosed balance after: 9,983

F1 · shares: These shares were allocated during the fourth quarter pursuant to the Old Second Bancorp, Inc. Salary & Savings Plan. Information herein was provided by the Plan Trustee as of 12-31-24.

SEC source: 0001415889-25-000062 · form4-01022025_070139.xml · nonDerivative · entry 2

Eccher James · CIK 0001314109 · Director · CHAIRMAN AND CEO

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K

Disclosed balance after: 32,258

F2 · shares: These shares were allocated during the fourth quarter pursuant to the Old Second Bancorp, Inc. Employee Salary & Savings Plan. Information herein was provided by the Plan Trustee as of 12-31-24.

SEC source: 0001415889-25-000062 · form4-01022025_070139.xml · nonDerivative · entry 1

Eccher James · CIK 0001314109 · Director · CHAIRMAN AND CEO

10b5-1 filing: No plan indicated

Ownership: Indirect · By Profit Sharing

Disclosed balance after: 6,247

F1 · shares: These shares were allocated during the fourth quarter pursuant to the Old Second Bancorp, Inc. Employee Profit Sharing Plan & Trust. Information herein was provided by the Plan Trustee as of 12-31-24.

SEC source: 0001415889-25-000060 · form4-01022025_070116.xml · nonDerivative · entry 1

COLLINS GARY S · CIK 0001184766 · Director · VICE CHAIRMAN

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K

Disclosed balance after: 6,370

F1 · shares: These shares were allocated during the fourth quarter pursuant to the Old Second Bancorp, Inc. Salary & Savings Plan. Information herein was provided by the Plan Trustee as of 12-31-24.

SEC source: 0001415889-25-000058 · form4-01022025_060110.xml · nonDerivative · entry 2

Pilmer Donald · CIK 0001673321 · EVP

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K Plan

Disclosed balance after: 3,954

F2 · shares: These shares were allocated during the fourth quarter pursuant to the Old Second Bancorp, Inc. Employee Salary & Savings Plan. Information herein was provided by the Plan Trustee as of 12-31-24.

SEC source: 0001415889-25-000058 · form4-01022025_060110.xml · nonDerivative · entry 1

Pilmer Donald · CIK 0001673321 · EVP

10b5-1 filing: No plan indicated

Ownership: Indirect · By Profit Sharing Plan

Disclosed balance after: 180

F1 · shares: This share was allocated during the fourth quarter pursuant to the Old Second Bancorp, Inc. Profit Sharing Plan & Trust. Information herein was provided by the Plan Trustee as of 12-31-24.

SEC source: 0001415889-25-000056 · form4-01022025_060159.xml · nonDerivative · entry 1

Gartelmann Richard A JR · CIK 0001840027 · EVP

10b5-1 filing: No plan indicated

Ownership: Indirect · By 401-K

Disclosed balance after: 12,177

F1 · shares: These shares were allocated during the fourth quarter pursuant to the Old Second Bancorp, Inc. Employee Salary & Savings Plan & Trust. Information herein was provided by the Plan Trustee as of 12-31-24.

SEC source: 0001415889-24-030144 · form4-12262024_071243.xml · nonDerivative · entry 1

Temple Rocks Patti · CIK 0001655300 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · IRA

Disclosed balance after: 18,678.85

SEC source: 0001415889-24-026569 · form4-11122024_061110.xml · nonDerivative · entry 1

Ladowicz John · CIK 0001424453 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · IRA

Disclosed balance after: 175,304

F1 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $18.2107 to $18.31, inclusive. The reporting person undertakes to provide to Old Second Bancorp, Inc., any security holder of Old Second Bancorp, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote.

SEC source: 0001415889-24-026085 · form4-11052024_031150.xml · nonDerivative · entry 1

Lyons Billy J Jr. · CIK 0001829064 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 13,793

F1 · balance_after: Of this total, 5,273 shares are held in Mr. Lyons' name outright and 8,520 shares are held with a broker.