ARWR

SEC source: 0001628280-25-013210 · wk-form4_1742247926.xml · nonDerivative · entry 2

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,062,377

F2 · shares: Partial disposition of shares to satisfy tax withholding obligations.

F3 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $14.83 to $15.76, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-013210 · wk-form4_1742247926.xml · nonDerivative · entry 1

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,113,802

F1 · shares: Represents performance awards granted on December 22, 2023, and certified on March 12, 2025, upon the achievement of certain performance goals.

SEC source: 0001628280-25-010672 · wk-form4_1741217520.xml · nonDerivative · entry 4

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 3,773,802

F1 · kind: The exercise of non-qualified stock options and sale was made as the stock options were approaching their expiration date. The shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F2 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $ 16.58 to $ 17.48, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

SEC source: 0001628280-25-010672 · wk-form4_1741217520.xml · nonDerivative · entry 2

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 4,073,802

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.

SEC source: 0001628280-25-010672 · wk-form4_1741217520.xml · derivative · entry 6

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 51,726

Underlying: Common Stock · 133,333 shares

Expires 2025-03-06

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.

F3 · derivative.exercise_date: All options were fully vested and exercisable as of March 6, 2015.

SEC source: 0001628280-25-010672 · wk-form4_1741217520.xml · derivative · entry 5

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 185,059

Underlying: Common Stock · 166,667 shares

Expires 2025-03-06

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.

F3 · derivative.exercise_date: All options were fully vested and exercisable as of March 6, 2015.

SEC source: 0001628280-25-010672 · wk-form4_1741217520.xml · nonDerivative · entry 3

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 3,907,135

F1 · kind: The exercise of non-qualified stock options and sale was made as the stock options were approaching their expiration date. The shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

SEC source: 0001628280-25-010672 · wk-form4_1741217520.xml · nonDerivative · entry 1

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 3,940,469

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.

SEC source: 0001628280-25-004708 · wk-form4_1739229790.xml · nonDerivative · entry 1

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 3,773,802

F1 · shares: Shares represent equity in lieu of part of his year-end cash bonus.

F2 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-004478 · wk-form4_1738969065.xml · nonDerivative · entry 1

INGRAM DOUGLAS S · CIK 0001190644 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 38,396

F1 · shares: Represents shares underlying restricted stock units with a grant date 02/06/2025, which will vest in three years.

SEC source: 0001628280-25-002716 · wk-form4_1738023770.xml · nonDerivative · entry 1

OLUKOTUN ADEOYE Y · CIK 0001242615 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 35,781

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F2 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-000806 · wk-form4_1736303281.xml · nonDerivative · entry 4

O'Brien Patrick · CIK 0001627183 · COO and General Counsel

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 527,201

F2 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F7 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $ 19.64 to $19.78, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F3 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F5 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-000805 · wk-form4_1736303271.xml · nonDerivative · entry 5

Myszkowski Kenneth Allen · CIK 0001486672 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 455,433

F8 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $19.62 to $19.78, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F5 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-000805 · wk-form4_1736303271.xml · nonDerivative · entry 4

Myszkowski Kenneth Allen · CIK 0001486672 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 465,433

F2 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F7 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $ 19.64 to $ 19.79, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F3 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F5 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-000807 · wk-form4_1736303292.xml · nonDerivative · entry 3

Hamilton James C · CIK 0001830755 · Chief Discovery/Trans Medicine

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 272,122

F2 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F6 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $20.01 to $20.22, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F3 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F5 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-000807 · wk-form4_1736303292.xml · nonDerivative · entry 2

Hamilton James C · CIK 0001830755 · Chief Discovery/Trans Medicine

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 283,093

F2 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F4 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $19.16 to $20.00, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F3 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F5 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-000806 · wk-form4_1736303281.xml · nonDerivative · entry 3

O'Brien Patrick · CIK 0001627183 · COO and General Counsel

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 535,201

F2 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F6 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $ 20.01 to $ 20.21, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F3 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F5 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-000806 · wk-form4_1736303281.xml · nonDerivative · entry 2

O'Brien Patrick · CIK 0001627183 · COO and General Counsel

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 544,727

F2 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F4 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $19.16 to $20.00, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F3 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F5 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-000805 · wk-form4_1736303271.xml · nonDerivative · entry 3

Myszkowski Kenneth Allen · CIK 0001486672 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 473,433

F2 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F6 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $20.01 to $20.20, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F3 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F5 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-000805 · wk-form4_1736303271.xml · nonDerivative · entry 2

Myszkowski Kenneth Allen · CIK 0001486672 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 482,835

F2 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F4 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $19.18 to $20.00, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F3 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F5 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-25-000807 · wk-form4_1736303292.xml · nonDerivative · entry 1

Hamilton James C · CIK 0001830755 · Chief Discovery/Trans Medicine

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 304,851

F1 · shares: Represents shares underlying restricted stock units with a grant date 01/04/2025, which will vest in four equal annual installments.

SEC source: 0001628280-25-000806 · wk-form4_1736303281.xml · nonDerivative · entry 1

O'Brien Patrick · CIK 0001627183 · COO and General Counsel

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 564,385

F1 · shares: Represents shares underlying restricted stock units with a grant date 01/04/2025, which will vest in four equal annual installments.

SEC source: 0001628280-25-000805 · wk-form4_1736303271.xml · nonDerivative · entry 1

Myszkowski Kenneth Allen · CIK 0001486672 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 500,600

F1 · shares: Represents shares underlying restricted stock units with a grant date 01/04/2025, which will vest in four equal annual installments.

SEC source: 0001628280-25-000673 · wk-form4_1736204845.xml · nonDerivative · entry 1

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 3,764,252

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $ 18.76 to $19.60, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F2 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-052592 · wk-form4_1735596735.xml · nonDerivative · entry 1

OLUKOTUN ADEOYE Y · CIK 0001242615 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 36,740

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F2 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-052347 · wk-form4_1734989985.xml · nonDerivative · entry 1

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 3,775,772

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $ 19.39 to $ 19.85, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F2 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-052274 · wk-form4_1734735918.xml · nonDerivative · entry 1

Vakiener Victoria · CIK 0001826263 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 37,944

F1 · shares: Represents shares underlying restricted stock units, which shares will vest in one installment on the first anniversary date.

SEC source: 0001628280-24-052271 · wk-form4_1734735898.xml · nonDerivative · entry 1

Waddill William D. · CIK 0001553338 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 57,111

F1 · shares: Represents shares underlying restricted stock units, which shares will vest in one installment on the first anniversary date.

SEC source: 0001628280-24-052273 · wk-form4_1734735909.xml · nonDerivative · entry 1

OLUKOTUN ADEOYE Y · CIK 0001242615 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 39,590

F1 · shares: Represents shares underlying restricted stock units, which shares will vest in one installment on the first anniversary date.

SEC source: 0001628280-24-052270 · wk-form4_1734735889.xml · nonDerivative · entry 1

Ferrari Mauro · CIK 0001506045 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 77,514

F1 · shares: Represents shares underlying restricted stock units, which shares will vest in one installment on the first anniversary date.

SEC source: 0001628280-24-052269 · wk-form4_1734735879.xml · nonDerivative · entry 1

PERRY MICHAEL S · CIK 0001250379 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 131,490

F1 · shares: Represents shares underlying restricted stock units, which shares will vest in one installment on the first anniversary date.

SEC source: 0001628280-24-052268 · wk-form4_1734735870.xml · nonDerivative · entry 1

Lu Hongbo · CIK 0001767584 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 47,163

F1 · shares: Represents shares underlying restricted stock units, which shares will vest in one installment on the first anniversary date.

SEC source: 0001628280-24-052267 · wk-form4_1734735860.xml · nonDerivative · entry 4

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 3,788,335

F7 · shares: Represents shares underlying restricted stock units with a grant date 12/18/24, which will vest in four equal annual installments.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-052267 · wk-form4_1734735860.xml · nonDerivative · entry 3

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 3,688,335

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F6 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $22.05 to $22.27, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F2 · acquired: Partial disposition of performance RSUs to satisfy tax withholding obligations. The performance RSUs were subject to a performance condition, which the Compensation Committee of the Company certified as achieved on December 17, 2024.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-052267 · wk-form4_1734735860.xml · nonDerivative · entry 2

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 3,694,134

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F5 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $21.18 to $22.04, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F2 · acquired: Partial disposition of performance RSUs to satisfy tax withholding obligations. The performance RSUs were subject to a performance condition, which the Compensation Committee of the Company certified as achieved on December 17, 2024.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-052267 · wk-form4_1734735860.xml · nonDerivative · entry 1

Anzalone Christopher Richard · CIK 0001423029 · Director · Chief Executive Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 3,702,394

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $20.15 to $21.11, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F2 · acquired: Partial disposition of performance RSUs to satisfy tax withholding obligations. The performance RSUs were subject to a performance condition, which the Compensation Committee of the Company certified as achieved on December 17, 2024.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-051925 · wk-form4_1734563946.xml · nonDerivative · entry 2

Waddill William D. · CIK 0001553338 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 40,378

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F2 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-051924 · wk-form4_1734563922.xml · nonDerivative · entry 2

GIVEN DOUGLAS B · CIK 0001156207 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 124,167

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F2 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-051925 · wk-form4_1734563946.xml · nonDerivative · entry 1

Waddill William D. · CIK 0001553338 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 44,125

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $21.64 to $22.22, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F2 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-051924 · wk-form4_1734563922.xml · nonDerivative · entry 1

GIVEN DOUGLAS B · CIK 0001156207 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 124,714

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $21.64 to $22.20, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F2 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-051923 · wk-form4_1734563707.xml · nonDerivative · entry 1

Vakiener Victoria · CIK 0001826263 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 21,211

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F3 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $21.54 to $22.20, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F2 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F4 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-048162 · wk-form5_1731720845.xml · nonDerivative · entry 6

Lu Hongbo · CIK 0001767584 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 30,430

F2 · ownership.direct: On September 25, 2024, the Reporting Person transferred 5,650 shares of the Issuer's common stock from a jointly-held retirement account to her spouse's individual retirement account for no consideration.

SEC source: 0001628280-24-031188 · wk-form4_1720042050.xml · nonDerivative · entry 1

Oliver Tracie · CIK 0001935706 · Chief Commercial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 127,107

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F2 · acquired: Partial disposition of RSUs to satisfy tax withholding obligations.

F3 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-020774 · wk-form4_1715033068.xml · nonDerivative · entry 1

Vakiener Victoria · CIK 0001826263 · Director

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 30,205

F1 · kind: Shares were sold pursuant to a 10b5-1 trading plan adopted by the Reporting Person in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended.

F2 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $23.05 to $23.46, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F3 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-048162 · wk-form5_1731720845.xml · nonDerivative · entry 5

Lu Hongbo · CIK 0001767584 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 36,080

F1 · balance_after: Includes previously reported restricted stock units, which are subject to certain vesting conditions.

SEC source: 0001628280-24-048162 · wk-form5_1731720845.xml · nonDerivative · entry 4

Lu Hongbo · CIK 0001767584 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 35,580

F1 · balance_after: Includes previously reported restricted stock units, which are subject to certain vesting conditions.

SEC source: 0001628280-24-048162 · wk-form5_1731720845.xml · nonDerivative · entry 3

Lu Hongbo · CIK 0001767584 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 35,080

F1 · balance_after: Includes previously reported restricted stock units, which are subject to certain vesting conditions.

SEC source: 0001628280-24-014735 · wk-form4_1712181913.xml · nonDerivative · entry 1

Hamilton James C · CIK 0001830755 · Chief Discovery/Trans Medicine

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 204,851

F1 · price: The price reported on Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $ 27.97 to $ 28.10, inclusive. The reporting person undertakes to provide to Arrowhead Pharmaceuticals, Inc., any security holder of Arrowhead Pharmaceuticals, 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 of this Form 4.

F2 · balance_after: Includes previously reported shares of common stock underlying Restricted Stock Units granted to the Reporting person which are subject to certain vesting conditions.

SEC source: 0001628280-24-048162 · wk-form5_1731720845.xml · nonDerivative · entry 2

Lu Hongbo · CIK 0001767584 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,930

F1 · balance_after: Includes previously reported restricted stock units, which are subject to certain vesting conditions.

SEC source: 0001628280-24-048162 · wk-form5_1731720845.xml · nonDerivative · entry 1

Lu Hongbo · CIK 0001767584 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 34,080

F1 · balance_after: Includes previously reported restricted stock units, which are subject to certain vesting conditions.