ADTN

SEC source: 0000926282-22-000003 · primary_doc.xml · nonDerivative · entry 3

Nair Balan · CIK 0001398905 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 74,153

F2 · security: Represents restricted stock award grant that vests in full on the first anniversary of the date of grant.

SEC source: 0000926282-22-000003 · primary_doc.xml · nonDerivative · entry 2

Nair Balan · CIK 0001398905 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 70,210

F1 · security: Settlement of dividend equivalent rights in connection with lapse of restriction on restricted stock. The rights accrued when and as dividends were paid on the Company's common stock and are paid in whole shares of common stock with the remainder paid in cash. Each dividend equivalent right is the economic equivalent of one share of the Company's common stock.

SEC source: 0000926282-22-000003 · primary_doc.xml · nonDerivative · entry 1

Nair Balan · CIK 0001398905 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 70,210.476

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Settlement of dividend equivalent rights in connection with lapse of restriction on restricted stock. The rights accrued when and as dividends were paid on the Company's common stock and are paid in whole shares of common stock with the remainder paid in cash. Each dividend equivalent right is the economic equivalent of one share of the Company's common stock.

SEC source: 0000926282-22-000001 · primary_doc.xml · derivative · entry 4

HUSS H FENWICK · CIK 0001201037 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 114.476 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Settlement of dividend equivalent rights in connection with lapse of restriction on restricted stock. The rights accrued when and as dividends were paid on the Company's common stock and are paid in whole shares of common stock with the remainder paid in cash. Each dividend equivalent right is the economic equivalent of one share of the Company's common stock.

F1 · derivative.exercise_date: Settlement of dividend equivalent rights in connection with lapse of restriction on restricted stock. The rights accrued when and as dividends were paid on the Company's common stock and are paid in whole shares of common stock with the remainder paid in cash. Each dividend equivalent right is the economic equivalent of one share of the Company's common stock.

F1 · derivative.expiration_date: Settlement of dividend equivalent rights in connection with lapse of restriction on restricted stock. The rights accrued when and as dividends were paid on the Company's common stock and are paid in whole shares of common stock with the remainder paid in cash. Each dividend equivalent right is the economic equivalent of one share of the Company's common stock.

SEC source: 0000926282-22-000001 · primary_doc.xml · nonDerivative · entry 3

HUSS H FENWICK · CIK 0001201037 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 56,380

F2 · security: Represents restricted stock award grant that vests in full on the first anniversary of the date of grant.

SEC source: 0000926282-22-000001 · primary_doc.xml · nonDerivative · entry 2

HUSS H FENWICK · CIK 0001201037 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 52,437

F1 · security: Settlement of dividend equivalent rights in connection with lapse of restriction on restricted stock. The rights accrued when and as dividends were paid on the Company's common stock and are paid in whole shares of common stock with the remainder paid in cash. Each dividend equivalent right is the economic equivalent of one share of the Company's common stock.

SEC source: 0000926282-22-000001 · primary_doc.xml · nonDerivative · entry 1

HUSS H FENWICK · CIK 0001201037 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 52,437.476

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Settlement of dividend equivalent rights in connection with lapse of restriction on restricted stock. The rights accrued when and as dividends were paid on the Company's common stock and are paid in whole shares of common stock with the remainder paid in cash. Each dividend equivalent right is the economic equivalent of one share of the Company's common stock.

SEC source: 0000926282-22-000006 · primary_doc.xml · nonDerivative · entry 3

Jacqueline Hourigan Rice · CIK 0001637150 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · As Trustee

Disclosed balance after: 35,333

F4 · balance_after: The reporting person is filing this amendment to correct the number of shares of the Company's common stock beneficially owned after the reported transaction. The previous reported total was 41,427 shares of the Company's common stock.

SEC source: 0000926282-22-000006 · primary_doc.xml · nonDerivative · entry 2

Jacqueline Hourigan Rice · CIK 0001637150 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · As Trustee

Disclosed balance after: 35,333.476

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · price: Settlement of dividend equivalent rights in connection with lapse of restriction on restricted stock. The rights accrued when and as dividends were paid on the Company's common stock and are paid in whole shares of common stock with the remainder paid in cash. Each dividend equivalent right is the economic equivalent of one share of the Company's common stock.

F3 · balance_after: The reporting person is filing this amendment to correct the number of shares of the Company's common stock beneficially owned after the reported transaction. The previous reported total was 41,427.476 shares of the Company's common stock.

SEC source: 0000926282-22-000006 · primary_doc.xml · nonDerivative · entry 1

Jacqueline Hourigan Rice · CIK 0001637150 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · As Trustee

Disclosed balance after: 35,219

F1 · balance_after: The reporting person is filing this amendment to correct the number of shares of the Company's common stock beneficially owned after the reported transaction. The previous reported total was 41,313 shares of the Company's common stock.

SEC source: 0000926282-22-000021 · primary_doc.xml · nonDerivative · entry 1

Foliano Michael · CIK 0001300513 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 52,847.899

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

SEC source: 0000926282-21-000084 · primary_doc.xml · derivative · entry 3

Wilson James Denson Jr · CIK 0001371377 · Chief Revenue Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 17,041.31

Underlying: Common Stock · 73.111 shares

Expires not disclosed

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

F2 · derivative.exercise_price: Each share of phantom stock represents a right to receive one share of common stock at the cash value thereof.

F3 · derivative.exercise_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

F3 · derivative.expiration_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

SEC source: 0000926282-21-000084 · primary_doc.xml · nonDerivative · entry 2

Wilson James Denson Jr · CIK 0001371377 · Chief Revenue Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 54,386.218

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

SEC source: 0000926282-21-000084 · primary_doc.xml · nonDerivative · entry 1

Wilson James Denson Jr · CIK 0001371377 · Chief Revenue Officer

10b5-1 filing: Not disclosed

Ownership: Indirect · 401(k) Plan

Disclosed balance after: 4,081.962

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

SEC source: 0000926282-21-000085 · primary_doc.xml · nonDerivative · entry 1

Centis Ronald · CIK 0001769038 · SVP, Operations

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,870.54

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

SEC source: 0000926282-21-000083 · primary_doc.xml · nonDerivative · entry 1

Scheiterer Eduard · CIK 0001628537 · SVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 40,027.285

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

SEC source: 0000926282-21-000082 · primary_doc.xml · derivative · entry 2

McCray Gregory James · CIK 0001327057 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 114.476

Underlying: Common Stock · 26.912 shares

Expires not disclosed

F2 · derivative.exercise_price: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

F2 · derivative.exercise_date: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

F2 · derivative.expiration_date: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

SEC source: 0000926282-21-000082 · primary_doc.xml · nonDerivative · entry 1

McCray Gregory James · CIK 0001327057 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 31,786.706

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

SEC source: 0000926282-21-000081 · primary_doc.xml · derivative · entry 2

STANTON THOMAS R · CIK 0001191219 · Director · Chairman and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 157,955.354

Underlying: Common Stock · 434.911 shares

Expires not disclosed

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

F2 · derivative.exercise_price: Each share of phantom stock represents a right to receive one share of common stock at the cash value thereof.

F3 · derivative.exercise_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

F3 · derivative.expiration_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

SEC source: 0000926282-21-000081 · primary_doc.xml · nonDerivative · entry 1

STANTON THOMAS R · CIK 0001191219 · Director · Chairman and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 304,869.41

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

SEC source: 0000926282-21-000080 · primary_doc.xml · derivative · entry 1

Walker Kathryn A · CIK 0001264261 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 114.476

Underlying: Common Stock · 26.912 shares

Expires not disclosed

F1 · derivative.exercise_price: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

F1 · derivative.exercise_date: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

F1 · derivative.expiration_date: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

SEC source: 0000926282-21-000078 · primary_doc.xml · derivative · entry 1

Nair Balan · CIK 0001398905 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 114.476

Underlying: Common Stock · 26.912 shares

Expires not disclosed

F1 · derivative.exercise_price: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

F1 · derivative.exercise_date: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

F1 · derivative.expiration_date: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

SEC source: 0000926282-21-000079 · primary_doc.xml · derivative · entry 1

Jacqueline Hourigan Rice · CIK 0001637150 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 114.476

Underlying: Common Stock · 26.912 shares

Expires not disclosed

F1 · derivative.exercise_price: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

F1 · derivative.exercise_date: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

F1 · derivative.expiration_date: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

SEC source: 0000926282-21-000077 · primary_doc.xml · derivative · entry 1

HUSS H FENWICK · CIK 0001201037 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 114.476

Underlying: Common Stock · 26.912 shares

Expires not disclosed

F1 · derivative.exercise_price: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

F1 · derivative.exercise_date: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

F1 · derivative.expiration_date: Dividend equivalent rights accrue when and as dividends are paid on the Company's common stock. The rights are paid in whole shares of common stock with the remainder paid in cash upon vesting of restricted stock units. Each dividend equivalent right is the equivalent of one share of the Company's common stock.

SEC source: 0000926282-21-000076 · primary_doc.xml · nonDerivative · entry 1

Kimpe Marc · CIK 0001770330 · SVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 27,445.647

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

SEC source: 0000926282-21-000075 · primary_doc.xml · nonDerivative · entry 1

Harris Ray · CIK 0001766181 · Chief Information Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,651.34

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

SEC source: 0000926282-21-000074 · primary_doc.xml · derivative · entry 2

Foliano Michael · CIK 0001300513 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 20,921.665

Underlying: Common Stock · 89.76 shares

Expires not disclosed

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

F2 · derivative.exercise_price: Each share of phantom stock represents a right to receive one share of common stock at the cash value thereof.

F3 · derivative.exercise_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

F3 · derivative.expiration_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

SEC source: 0000926282-21-000074 · primary_doc.xml · nonDerivative · entry 1

Foliano Michael · CIK 0001300513 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Indirect · 401(k) Plan

Disclosed balance after: 245.822

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

SEC source: 0000926282-22-000022 · primary_doc.xml · derivative · entry 1

STANTON THOMAS R · CIK 0001191219 · Director · Chairman and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 156,869.354

Underlying: Common Stock · 244 shares

Expires not disclosed

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

F2 · derivative.exercise_price: Each share of phantom stock represents a right to receive one share of common stock at the cash value thereof.

F3 · derivative.exercise_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

F3 · derivative.expiration_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

SEC source: 0000926282-22-000040 · primary_doc.xml · nonDerivative · entry 4

Conger Robert · CIK 0001844323 · SVP, Technology & Strategy

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 18,155.718

F1 · security: Reflects shares acquired through the automatic reinvestment of dividends paid on the Company's common stock.

SEC source: 0000926282-21-000065 · primary_doc.xml · nonDerivative · entry 2

Harris Ray · CIK 0001766181 · Chief Information Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,851.31

F1 · security: Represents a grant of restricted stock units that vest in four equal and annual installments beginning on the first anniversary date of the grant.

SEC source: 0000926282-21-000073 · primary_doc.xml · nonDerivative · entry 1

Harris Ray · CIK 0001766181 · Chief Information Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,648.31

F1 · security: We previously reported that 4,215 restricted stock units were granted. The actual number of restricted stock units granted was 4,012. The revised amount of securities beneficially owned following this correction is 16,648.31. The restricted stock units vest in four equal and annual installments beginning on the first anniversary date of the grant.

SEC source: 0000926282-21-000072 · primary_doc.xml · nonDerivative · entry 2

Wilson James Denson Jr · CIK 0001371377 · Chief Revenue Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 54,294.608

F2 · security: Represents a grant of restricted stock units that vest in four equal and annual installments beginning on the first anniversary date of the grant.

SEC source: 0000926282-21-000072 · primary_doc.xml · nonDerivative · entry 1

Wilson James Denson Jr · CIK 0001371377 · Chief Revenue Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 47,918.608

F1 · security: Represents vesting of performance shares awarded pursuant to a grant on November 9, 2018 under the ADTRAN, Inc. 2015 Employee Stock Incentive Plan.

SEC source: 0000926282-21-000070 · primary_doc.xml · nonDerivative · entry 1

Kimpe Marc · CIK 0001770330 · SVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 27,421.316

F1 · security: Represents a grant of restricted stock units that vest in four equal and annual installments beginning on the first anniversary date of the grant.

SEC source: 0000926282-21-000071 · primary_doc.xml · nonDerivative · entry 1

Scheiterer Eduard · CIK 0001628537 · SVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 39,952.845

F1 · security: Represents vesting of performance shares awarded pursuant to a grant on November 9, 2018 under the ADTRAN, Inc. 2015 Employee Stock Incentive Plan.

SEC source: 0000926282-21-000069 · primary_doc.xml · nonDerivative · entry 2

Foliano Michael · CIK 0001300513 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 52,810.88

F2 · security: Represents a grant of restricted stock units that vest in four equal and annual installments beginning on the first anniversary date of the grant.

SEC source: 0000926282-21-000069 · primary_doc.xml · nonDerivative · entry 1

Foliano Michael · CIK 0001300513 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 46,073.88

F1 · security: Represents vesting of performance shares awarded pursuant to a grant on November 9, 2018 under the ADTRAN, Inc. 2015 Employee Stock Incentive Plan.

SEC source: 0000926282-21-000066 · primary_doc.xml · derivative · entry 2

STANTON THOMAS R · CIK 0001191219 · Director · Chairman and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 157,520.443

Underlying: Common Stock · 56,584 shares

Expires not disclosed

F2 · security: Represents vesting of performance shares awarded pursuant to a grant on November 09, 2018 under the ADTRAN, Inc. 2015 Employee Stock Incentive Plan.

F3 · derivative.exercise_price: Each share of phantom stock represents a right to receive one share of common stock at the cash value thereof.

F4 · derivative.exercise_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

F4 · derivative.expiration_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

SEC source: 0000926282-21-000066 · primary_doc.xml · nonDerivative · entry 1

STANTON THOMAS R · CIK 0001191219 · Director · Chairman and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 304,646.18

F1 · security: Represents a grant of restricted stock units that vest in four equal and annual installments beginning on the first anniversary date of the grant.

SEC source: 0000926282-21-000068 · primary_doc.xml · nonDerivative · entry 1

Conger Robert · CIK 0001844323 · SVP, Technology & Strategy

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 18,039.598

F1 · security: Represents a grant of restricted stock units that vest in four equal and annual installments beginning on the first anniversary date of the grant.

SEC source: 0000926282-21-000067 · primary_doc.xml · nonDerivative · entry 1

Centis Ronald · CIK 0001769038 · SVP, Operations

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,857.565

F1 · security: Represents a grant of restricted stock units that vest in four equal and annual installments beginning on the first anniversary date of the grant.

SEC source: 0000926282-21-000086 · primary_doc.xml · derivative · entry 1

STANTON THOMAS R · CIK 0001191219 · Director · Chairman and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 156,190.443

Underlying: Common Stock · 1,330 shares

Expires not disclosed

F1 · security: On November 19, 2021, the reporting person filed a Form 4 which inadvertently omitted the withholding of taxes in connection with the vesting of performance shares awarded pursuant to a grant on November 9, 2018 under the ADTRAN, Inc. 2015 Employee Stock Incentive Plan.

F2 · derivative.exercise_price: Each share of phantom stock represents a right to receive one share of common stock at the cash value thereof.

F3 · derivative.exercise_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

F3 · derivative.expiration_date: The phantom stock becomes payable six months after the reporting person's separation of service with the Company. The reporting person may transfer the phantom stock account into an alternative investment at any time.

F4 · balance_after: This inadvertent error caused the Number of Derivative Securities Beneficially Owned Following Reported Transaction in Column 9 in the Form 4 filed by the reporting person on December 2, 2021 to be overstated by 1,330 shares.

SEC source: 0000926282-21-000087 · primary_doc.xml · nonDerivative · entry 2

Wilson James Denson Jr · CIK 0001371377 · Chief Revenue Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 47,309.608

F3 · security: On November 19, 2021, the reporting person filed a Form 4 which inadvertently netted the vesting of performance shares against shares withheld for taxes. In addition, the the Form 4 inadvertently omitted the withholding of an additional 609 shares for taxes. These shares represent the vesting of performance shares awarded pursuant to a grant on November 9, 2018 under the ADTRAN, Inc. 2015 Employee Stock Incentive Plan.

F2 · balance_after: This inadvertent error caused the number of Common Shares Beneficially Owned following the reported transaction to be incorrect. The new amount in column 5 reflects the corrected Common Shares Beneficially Owned.

SEC source: 0000926282-21-000087 · primary_doc.xml · nonDerivative · entry 1

Wilson James Denson Jr · CIK 0001371377 · Chief Revenue Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 50,884.608

F1 · security: On November 19, 2021, the reporting person filed a Form 4 which inadvertently netted the vesting of performance shares against shares withheld for taxes. These shares represent the vesting of performance shares awarded pursuant to a grant on November 9, 2018 under the ADTRAN, Inc. 2015 Employee Stock Incentive Plan.

F2 · balance_after: This inadvertent error caused the number of Common Shares Beneficially Owned following the reported transaction to be incorrect. The new amount in column 5 reflects the corrected Common Shares Beneficially Owned.

SEC source: 0000926282-21-000088 · primary_doc.xml · nonDerivative · entry 2

Foliano Michael · CIK 0001300513 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 46,073.88

F1 · security: On November 19, 2021, the reporting person filed a Form 4 which inadvertently netted the vesting of performance shares against shares withheld for taxes. These shares represent the vesting of performance shares awarded pursuant to a grant on November 9, 2018 under the ADTRAN, Inc. 2015 Employee Stock Incentive Plan.

F2 · balance_after: This inadvertent error caused the number of Common Shares Beneficially Owned following the reported transaction to be incorrect. The new amount in column 5 reflects the corrected Common Shares Beneficially Owned.

SEC source: 0000926282-21-000088 · primary_doc.xml · nonDerivative · entry 1

Foliano Michael · CIK 0001300513 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 48,783.88

F1 · security: On November 19, 2021, the reporting person filed a Form 4 which inadvertently netted the vesting of performance shares against shares withheld for taxes. These shares represent the vesting of performance shares awarded pursuant to a grant on November 9, 2018 under the ADTRAN, Inc. 2015 Employee Stock Incentive Plan.

F2 · balance_after: This inadvertent error caused the number of Common Shares Beneficially Owned following the reported transaction to be incorrect. The new amount in column 5 reflects the corrected Common Shares Beneficially Owned.

SEC source: 0000926282-21-000063 · primary_doc.xml · nonDerivative · entry 2

Conger Robert · CIK 0001844323 · SVP, Technology & Strategy

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 13,739.598

SEC source: 0000926282-21-000064 · primary_doc.xml · nonDerivative · entry 2

Centis Ronald · CIK 0001769038 · SVP, Operations

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 20,606.565

SEC source: 0000926282-21-000062 · primary_doc.xml · nonDerivative · entry 2

Kimpe Marc · CIK 0001770330 · SVP, Research & Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 23,205.316