ARROWHEAD PHARMACEUTICALS IN ARWR
COM · Common Stock · CUSIP 04280A100 · ISIN US04280A1007
Biopharmaceutical company
- SectorHealth care
- IndustryPharmaceutical Preparations
- HeadquartersPasadena, CA
- Founded1989
- Websitearrowheadpharma.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($2.2m this quarter). Holder counts are more reliable. Shares outstanding: 140.9m as of 2026-05-01, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $62.70. Options: 16 managers hold calls ($106.3m notional), 14 hold puts ($55.8m).
Trends to Q1 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 278 |
| Q4 2022 | 283 |
| Q1 2023 | 257 |
| Q2 2023 | 274 |
| Q3 2023 | 258 |
| Q4 2023 | 267 |
| Q1 2024 | 276 |
| Q2 2024 | 274 |
| Q3 2024 | 273 |
| Q4 2024 | 271 |
| Q1 2025 | 266 |
| Q2 2025 | 282 |
| Q3 2025 | 303 |
| Q4 2025 | 402 |
| Q1 2026 | 438 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q2 2024 | 129 | 121 |
| Q3 2024 | 121 | 123 |
| Q4 2024 | 122 | 127 |
| Q1 2025 | 130 | 126 |
| Q2 2025 | 151 | 120 |
| Q3 2025 | 165 | 121 |
| Q4 2025 | 234 | 137 |
| Q1 2026 | 264 | 171 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q2 2025 | $8.2m | $10.6m | 1.28 |
| Q3 2025 | $39.1m | $9.8m | 0.25 |
| Q4 2025 | $156.8m | $38.8m | 0.25 |
| Q1 2026 | $106.3m | $55.8m | 0.53 |
Biggest buyers
| Invesco Ltd. | Added | +2.7m |
| FRED ALGER MANAGEMENT, LLC | Added | +1.5m |
| Vestal Point Capital, LP | Added | +1.4m |
| Hood River Capital Management LLC | New | +1.1m |
| D. E. Shaw & Co., Inc. | Added | +1.0m |
| RENAISSANCE TECHNOLOGIES LLC | New | +1.0m |
| GEODE CAPITAL MANAGEMENT, LLC | Added | +1.0m |
| FMR LLC | Added | +746.2k |
| AMERICAN CENTURY COMPANIES INC | Added | +643.8k |
| BNP PARIBAS FINANCIAL MARKETS | Added | +610.2k |
Biggest sellers
| BlackRock, Inc. | Reduced | -3.2m |
| Slate Path Capital LP | Sold out | -2.5m |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP | Reduced | -1.5m |
| Assenagon Asset Management S.A. | Reduced | -626.2k |
| Driehaus Capital Management LLC | Reduced | -579.0k |
| ADAGE CAPITAL PARTNERS GP, L.L.C. | Sold out | -550.0k |
| MORGAN STANLEY | Reduced | -515.5k |
| Public Sector Pension Investment Board | Sold out | -478.5k |
| CITADEL ADVISORS LLC | Reduced | -376.1k |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC | Sold out | -288.5k |
Biggest calls
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $58.6m934.9k shares |
| CITADEL ADVISORS LLC | Reduced | $11.7m187.0k shares |
| JANE STREET GROUP, LLC | Reduced | $9.7m155.2k shares |
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC | Reduced | $9.4m150.0k shares |
| Caption Management, LLC | Reduced | $4.3m68.6k shares |
| GROUP ONE TRADING LLC | Reduced | $4.1m65.1k shares |
| Point72 Asset Management, L.P. | Added | $2.2m34.9k shares |
| CITIGROUP INC | New | $1.3m20.5k shares |
| SIMPLEX TRADING, LLC | New | $1.2m19.4k shares |
| PEAK6 LLC | Reduced | $1.0m16.1k shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $32.8m522.7k shares |
| JANE STREET GROUP, LLC | Reduced | $7.2m114.1k shares |
| CITADEL ADVISORS LLC | Reduced | $4.1m65.3k shares |
| Ikarian Capital, LLC | New | $3.6m57.5k shares |
| Caption Management, LLC | New | $1.9m30.0k shares |
| CITIGROUP INC | New | $1.3m20.5k shares |
| HRT FINANCIAL LP | New | $1.1m17.6k shares |
| BOOTHBAY FUND MANAGEMENT, LLC | New | $1.1m16.8k shares |
| SIMPLEX TRADING, LLC | New | $1.0m16.7k shares |
| Point72 Asset Management, L.P. | Added | $721.0k11.5k shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| BlackRock, Inc. 13G · institution -2.1 pts · filed 2026-07-27 | 10.1% |
| Avoro Capital Advisors LLC 13G · institution +1.3 pts · filed 2026-08-14 | 9.6% |
| FMR LLC 13G · institution new · filed 2026-05-06 | 5.2% |
| VANGUARD CAPITAL MANAGEMENT LLC 13G · institution new · filed 2026-04-29 | 5.0% |
Fell to 5% or below in the last year: VANGUARD PORTFOLIO MANAGEMENT LLC (4.5%, 2026-07-31; now reported by VANGUARD CAPITAL MANAGEMENT LLC), VANGUARD GROUP INC (0.0%, 2026-03-26; now reported by VANGUARD CAPITAL MANAGEMENT LLC)
Insider purchases and sales in Q1 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q2 2024 | 1 | $27.6k | 2 | $210.1k | $41.9k |
| Q3 2024 | 0 | — | 1 | $237.5k | $237.5k |
| Q4 2024 | 0 | — | 5 | $1.4m | $1.4m |
| Q1 2025 | 0 | — | 5 | $8.6m | $7.8m |
| Q2 2025 | 0 | — | 1 | $1.5m | — |
| Q3 2025 | 0 | — | 1 | $1.0m | $1.0m |
| Q4 2025 | 0 | — | 7 | $27.8m | $8.5m |
| Q1 2026 | 0 | — | 3 | $7.2m | $7.2m |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2026-03-05 | Hamilton James C Chief Medical Officer | Sold plan | $641.9k10.0k shares |
| 2026-01-05 | O'Brien Patrick COO | Sold plan | $3.1m49.5k shares |
| 2026-01-05 | Hamilton James C Chief Medical Officer | Sold plan | $2.5m40.2k shares |
| 2026-01-02 | Anzalone Christopher Richard Chief Executive Officer, director | Sold plan | $871.7k13.2k shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q1 2026
| Manager | Shares | Change |
|---|---|---|
| BlackRock, Inc. 0.02% of their portfolio | 18.2m $1.1bn | Reduced -3.2m |
| Avoro Capital Advisors LLC 6.61% of their portfolio | 10.7m $670.9m | Added +75.0k |
| FMR LLC 0.02% of their portfolio | 7.3m $455.6m | Added +746.2k |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.02% of their portfolio | 7.1m $448.1m | First filing |
| STATE STREET CORP 0.01% of their portfolio | 6.5m $407.3m | Added +92.3k |
| VANGUARD CAPITAL MANAGEMENT LLC 0.01% of their portfolio | 6.0m $378.2m | First filing |
| GEODE CAPITAL MANAGEMENT, LLC 0.02% of their portfolio | 4.3m $274.5m | Added +1.0m |
| FRED ALGER MANAGEMENT, LLC 0.92% of their portfolio | 3.3m $209.6m | Added +1.5m |
| Invesco Ltd. 0.02% of their portfolio | 3.3m $205.7m | Added +2.7m |
| Vestal Point Capital, LP 3.99% of their portfolio | 2.3m $142.6m | Added +1.4m |
| BAKER BROS. ADVISORS LP 0.72% of their portfolio | 2.0m $124.9m | Reduced -182.9k |
| GOLDMAN SACHS GROUP INC 0.01% of their portfolio | 1.7m $109.1m | Added +62.4k |
| NORTHERN TRUST CORP 0.01% of their portfolio | 1.7m $103.8m | Added +309.6k |
| Siren, L.L.C. 2.81% of their portfolio | 1.6m $101.3m | Added +115.0k |
| DEERFIELD MANAGEMENT COMPANY, L.P. 1.16% of their portfolio | 1.6m $98.6m | Reduced -259.6k |
| JANUS HENDERSON GROUP PLC 0.04% of their portfolio | 1.4m $90.1m | Added +156.5k |
| UBS Group AG 0.01% of their portfolio | 1.3m $83.8m | Added +349.0k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.02% of their portfolio | 1.3m $83.5m | Added +70.6k |
| Pictet Asset Management Holding SA 0.08% of their portfolio | 1.3m $79.6m | Added +244.5k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.01% of their portfolio | 1.2m $74.7m | Reduced -161.6k |
| Driehaus Capital Management LLC 0.55% of their portfolio | 1.2m $74.6m | Reduced -579.0k |
| D. E. Shaw & Co., Inc. 0.06% of their portfolio | 1.2m $74.2m | Added +1.0m |
| Fisher Asset Management, LLC 0.02% of their portfolio | 1.1m $69.8m | Reduced -198.2k |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 1.1m $66.7m | Added +442.4k |
| Hood River Capital Management LLC 0.66% of their portfolio | 1.1m $66.2m | New |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.01% of their portfolio | 1.0m $65.4m | Added +204.9k |
| RENAISSANCE TECHNOLOGIES LLC 0.10% of their portfolio | 1.0m $65.0m | New |
| VANGUARD FIDUCIARY TRUST CO 0.02% of their portfolio | 965.8k $60.6m | First filing |
| MORGAN STANLEY 0.00% of their portfolio | 960.5k $60.2m | Reduced -515.5k |
| Bank of New York Mellon Corp 0.01% of their portfolio | 960.1k $60.2m | Added +72.3k |
| Connor, Clark & Lunn Investment Management Ltd. 0.12% of their portfolio | 837.0k $52.5m | Added +173.7k |
| Western Financial Corp/CA 20.13% of their portfolio | 820.2k $51.4m | Unchanged |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 683.1k $39.4m | Added +71.2k |
| VOYA INVESTMENT MANAGEMENT LLC 0.04% of their portfolio | 656.1k $41.1m | Added +233.4k |
| AMERICAN CENTURY COMPANIES INC 0.02% of their portfolio | 651.5k $40.9m | Added +643.8k |
| BNP PARIBAS FINANCIAL MARKETS 0.03% of their portfolio | 650.6k $40.8m | Added +610.2k |
| DIMENSIONAL FUND ADVISORS LP 0.01% of their portfolio | 608.5k $38.1m | Added +461.1k |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP 0.02% of their portfolio | 587.1k $36.8m | Reduced -1.5m |
| RTW INVESTMENTS, LP 0.37% of their portfolio | 585.7k $36.7m | Added +966 |
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC 1.57% of their portfolio | 540.1k $33.9m | Added +70.1k |
| Nuveen, LLC 0.01% of their portfolio | 499.8k $31.3m | Added +211.3k |
| PRINCIPAL FINANCIAL GROUP INC 0.02% of their portfolio | 490.1k $30.7m | Reduced -225.4k |
| Alyeska Investment Group, L.P. 0.08% of their portfolio | 472.9k $29.6m | Added +97.5k |
| FRANKLIN RESOURCES INC 0.01% of their portfolio | 462.7k $29.0m | Added +355.3k |
| PANAGORA ASSET MANAGEMENT INC 0.11% of their portfolio | 461.2k $28.9m | Added +425.2k |
| RHUMBLINE ADVISERS 0.02% of their portfolio | 404.4k $25.4m | Added +52.0k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.03% of their portfolio | 378.8k $23.8m | Added +349.9k |
| EVENTIDE ASSET MANAGEMENT, LLC 0.38% of their portfolio | 370.0k $23.2m | Unchanged |
| Privium Fund Management B.V. 4.79% of their portfolio | 366.9k $23.0m | Reduced -31.3k |
| Aberdeen Group plc 0.04% of their portfolio | 364.0k $22.8m | Added +77.8k |
| CANADA PENSION PLAN INVESTMENT BOARD 0.01% of their portfolio | 325.7k $20.4m | Added +297.1k |
| LORD, ABBETT & CO. LLC 0.06% of their portfolio | 312.8k $19.6m | New |
| NORDEA INVESTMENT MANAGEMENT AB 0.02% of their portfolio | 306.4k $18.6m | Reduced -17.8k |
| Integral Health Asset Management, LLC 1.00% of their portfolio | 300.0k $18.8m | Added +200.0k |
| ALLIANCEBERNSTEIN L.P. 0.01% of their portfolio | 280.4k $18.6m | Added +107.7k |
| Trexquant Investment LP 0.13% of their portfolio | 277.1k $17.4m | Added +26.2k |
| DEUTSCHE BANK AG\ 0.01% of their portfolio | 260.0k $16.3m | Added +17.9k |
| California Public Employees Retirement System 0.01% of their portfolio | 257.1k $16.1m | New |
| CITIGROUP INC 0.01% of their portfolio | 251.6k $15.8m | Added +208.8k |
| Swiss National Bank 0.01% of their portfolio | 242.0k $15.2m | Reduced -3.4k |
| Legal & General Group Plc 0.00% of their portfolio | 229.1k $14.4m | Reduced -166.2k |
| Balyasny Asset Management L.P. 0.03% of their portfolio | 206.4k $12.9m | Reduced -169.8k |
| NEUBERGER BERMAN GROUP LLC 0.01% of their portfolio | 203.9k $12.8m | Added +103.5k |
| SEI INVESTMENTS CO 0.01% of their portfolio | 203.2k $12.7m | Added +90.9k |
| Clearbridge Investments, LLC 0.01% of their portfolio | 202.3k $12.7m | Reduced -5.7k |
| Woodline Partners LP 0.05% of their portfolio | 200.2k $12.6m | Reduced -200.0k |
| Affinity Asset Advisors, LLC 0.74% of their portfolio | 200.0k $12.5m | Added +130.0k |
| Longaeva Partners L.P. 0.59% of their portfolio | 194.6k $12.2m | New |
| AMERIPRISE FINANCIAL INC 0.00% of their portfolio | 191.1k $12.0m | Reduced -66.4k |
| MUTUAL OF AMERICA CAPITAL MANAGEMENT LLC 0.13% of their portfolio | 184.3k $11.6m | Added +168.5k |
| RAYMOND JAMES FINANCIAL INC 0.00% of their portfolio | 182.6k $11.4m | Reduced -15.8k |
| MARSHALL WACE, LLP 0.01% of their portfolio | 179.6k $11.3m | Added +55.7k |
| PINNACLE ASSOCIATES LTD 0.14% of their portfolio | 175.5k $11.0m | Reduced -16.2k |
| Russell Investments Group, Ltd. 0.01% of their portfolio | 174.0k $10.9m | Added +51.9k |
| Retirement Systems of Alabama 0.04% of their portfolio | 171.7k $10.8m | New |
| WCM INVESTMENT MANAGEMENT, LLC 0.02% of their portfolio | 171.6k $9.9m | Added +32.7k |
| AQR CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 167.2k $10.3m | Added +19.9k |
| SCHRODER INVESTMENT MANAGEMENT GROUP 0.01% of their portfolio | 162.0k $9.3m | New |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.01% of their portfolio | 160.4k $10.1m | Added +62.3k |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 158.4k $9.9m | Added +5.9k |
| SEB Asset Management AB 0.04% of their portfolio | 158.2k $9.9m | First filing |
| HSBC HOLDINGS PLC 0.01% of their portfolio | 151.0k $9.5m | New |
| TORONTO DOMINION BANK 0.02% of their portfolio | 150.3k $9.4m | New |
| FIRST TRUST ADVISORS LP 0.01% of their portfolio | 149.1k $9.4m | Reduced -88.6k |
| HighTower Advisors, LLC 0.01% of their portfolio | 146.5k $9.2m | Added +13.2k |
| Rhenman & Partners Asset Management AB 1.12% of their portfolio | 144.5k $9.1m | Unchanged |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.01% of their portfolio | 144.3k $9.0m | Added +25.9k |
| WEALTH EFFECTS LLC 3.18% of their portfolio | 143.3k $9.0m | Unchanged |
| MetLife Investment Management, LLC 0.04% of their portfolio | 140.4k $8.8m | Added +67.4k |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.01% of their portfolio | 139.6k $8.7m | Added +5.7k |
| Empowered Funds, LLC 0.05% of their portfolio | 137.2k $8.6m | Added +119.2k |
| BANK OF NOVA SCOTIA 0.01% of their portfolio | 136.0k $8.5m | New |
| LPL Financial LLC 0.00% of their portfolio | 129.5k $8.1m | Added +29.2k |
| Tetragon Partners GP Ltd 1.57% of their portfolio | 127.2k $8.0m | Added +30.3k |
| NEW YORK STATE TEACHERS RETIREMENT SYSTEM 0.02% of their portfolio | 124.9k $7.8m | Reduced -24.9k |
| Universal- Beteiligungs- und Servicegesellschaft mbH 0.01% of their portfolio | 120.2k $7.5m | Reduced -39.3k |
| BARCLAYS PLC 0.00% of their portfolio | 115.3k $7.2m | Reduced -206.5k |
| VANGUARD ASSET MANAGEMENT, Ltd 0.01% of their portfolio | 113.0k $7.1m | First filing |
| SILVERCREST ASSET MANAGEMENT GROUP LLC 0.05% of their portfolio | 108.4k $6.8m | Reduced -50.2k |
| Cormorant Asset Management, LP 0.32% of their portfolio | 100.0k $6.3m | New |