Arrowhead Pharmaceuticals's three largest insider shareholders as of March 23, 2026 are Christopher Richard Anzalone (Chief Executive Officer, 3.79Mn shares), Patrick O'Brien (Coo, 547.41K shares), Kenneth Allen Myszkowski (Chief Financial Officer, 455.43K shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| Christopher Richard Anzalone | Chief Executive Officer | 3,792,739 | 0 | 05 Jan, 2026 |
| Patrick O'Brien | Coo | 547,408 | 0 | 08 Jan, 2026 |
| Kenneth Allen Myszkowski | Chief Financial Officer | 455,433 | 0 | 07 Jan, 2025 |
| James C Hamilton | Chief Medical Officer | 236,958 | 0 | 09 Mar, 2026 |
| Martin Javier San | Chief Medical Officer | 198,497 | 0 | 05 Jan, 2024 |
| Daniel Joseph Apel | Chief Financial Officer | 176,200 | 0 | 08 Jan, 2026 |
| Tracie Oliver | Chief Commercial Officer | 127,107 | 0 | 03 Jul, 2024 |
| Douglas B Given | 124,167 | 0 | 18 Dec, 2024 | |
| Michael S Perry | 123,059 | 0 | 18 Dec, 2025 | |
| James Hassard | Chief Commercial Officer | 105,750 | 0 | 24 Jun, 2021 |
| Mauro Ferrari | 69,053 | 0 | 30 Dec, 2025 | |
| William D. Waddill | 56,563 | 0 | 23 Dec, 2025 | |
| Hongbo Lu | 54,982 | 0 | 18 Dec, 2025 | |
| Douglas S Ingram | 46,215 | 0 | 18 Dec, 2025 | |
| Victoria Vakiener | 35,723 | 0 | 23 Dec, 2025 | |
| Adeoye Y Olukotun | 33,600 | 0 | 23 Dec, 2025 | |
| Backer Marianne De | 31,267 | 0 | 11 Jan, 2023 | |
| Douglas B Given | 0 | 13,000 | 01 Mar, 2023 |
* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.
| Transaction Date | Insider Name | Security Class | Transaction Type | Shares Traded | Price | Shares Remaining | Ownership | Code |
|---|---|---|---|---|---|---|---|---|
| 05 Mar, 2026 | James C Hamilton | Common Stock | D | 10,000 | $64.19 | 236,958 | D | S |
| 06 Jan, 2026 | Daniel Joseph Apel | Common Stock | A | 75,000 | $0.00 | 176,200 | D | A |
| 06 Jan, 2026 | James C Hamilton | Common Stock | A | 75,000 | $0.00 | 246,958 | D | A |
| 06 Jan, 2026 | Patrick O'Brien | Common Stock | D | 540 | $0.00 | 474,368 | D | G |
| 06 Jan, 2026 | Patrick O'Brien | Common Stock | D | 540 | $0.00 | 473,828 | D | G |
| 06 Jan, 2026 | Patrick O'Brien | Common Stock | D | 540 | $0.00 | 473,288 | D | G |
| 06 Jan, 2026 | Patrick O'Brien | Common Stock | D | 440 | $0.00 | 472,848 | D | G |
| 06 Jan, 2026 | Patrick O'Brien | Common Stock | D | 440 | $0.00 | 472,408 | D | G |
| 06 Jan, 2026 | Patrick O'Brien | Common Stock | A | 75,000 | $0.00 | 547,408 | D | A |
| 31 Dec, 2025 | Patrick O'Brien | Common Stock | D | 560 | $0.00 | 526,641 | D | G |
| 05 Jan, 2026 | James C Hamilton | Common Stock | D | 4,625 | $61.24 | 207,497 | D | S |
| 02 Jan, 2026 | Christopher Richard Anzalone | Common Stock | D | 7,416 | $65.88 | 3,798,510 | D | S |
| 31 Dec, 2025 | Patrick O'Brien | Common Stock | D | 560 | $0.00 | 526,081 | D | G |
| 05 Jan, 2026 | James C Hamilton | Common Stock | D | 6,090 | $62.28 | 201,407 | D | S |
| 02 Jan, 2026 | Christopher Richard Anzalone | Common Stock | D | 5,771 | $66.39 | 3,792,739 | D | S |
| 05 Jan, 2026 | James C Hamilton | Common Stock | D | 14,792 | $63.01 | 186,615 | D | S |
| 31 Dec, 2025 | Patrick O'Brien | Common Stock | D | 560 | $0.00 | 525,521 | D | G |
| 31 Dec, 2025 | Patrick O'Brien | Common Stock | D | 560 | $0.00 | 524,961 | D | G |
| 05 Jan, 2026 | James C Hamilton | Common Stock | D | 12,711 | $63.95 | 173,904 | D | S |
| 05 Jan, 2026 | James C Hamilton | Common Stock | D | 1,200 | $64.49 | 172,704 | D | S |