Who owns Arrowhead Pharmaceuticals (ARWR)
Which tracked institutional funds hold ARWR, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See ARWR company fundamentals →
Ownership as of the 2026-Q2 13F filings (latest filed 2026-09-22). 13F is disclosed up to 45 days after quarter-end, so the most recent quarter fills in over the following weeks.
How the tape is positioned
201 tracked funds added or opened ARWR while 99 trimmed or exited it between 2026-Q1 and 2026-Q2 — the tape is split. When large holders disagree on a name, the funds moving first are sometimes ahead of the story.
A prompt to read the filings, not a verdict. 13F is a quarter-end snapshot disclosed up to 45 days late; a fund adds or exits for mandate, benchmark, and timing reasons that have nothing to do with a view on the stock. This is a starting question, not a signal to trade.
Conviction spread
ARWR’s largest tracked holder by dollar value, BlackRock, Inc., sizes it at 0.0% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 0.0pp gap the other way — the median holder sizes ARWR more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in ARWR divided by its whole reported 13F book, so it is comparable across funds of different sizes and is unaffected by stock splits. A higher share means a fund has committed more of its book to the name — a starting question about conviction, not a verdict or a signal to trade.
Institutional & insider positioning
Between 2026-Q1 and 2026-Q2, across 468 tracked filers holding ARWR, 269 increased or opened the position and 234 reduced or closed it; over the same quarter, open-market insider Form 4s were net sales.
This fuses two public signals for the same quarter — how tracked institutions changed their positions and whether insiders bought or sold in the open market. It describes what was filed; it is a starting question, not a verdict or a signal to trade.
New buyers & exits
Funds opening or closing a position in ARWR between the 2026-Q1 and 2026-Q2 13F filings, and the largest changes among funds holding it in both. New buyers and exits are counted on fund presence (split-invariant); adds and trims are measured on reported value.
New buyers 46
- Jupiter Topco LLC$100M
- Holocene Advisors, LP$90M
- 1832 Asset Management L.P.$44M
- MILLENNIUM MANAGEMENT LLC$27M
- Artisan Partners Limited Partnership$25M
- Squarepoint Ops LLC$21M
Full exits 51
- JANUS HENDERSON GROUP PLC$90M
- RTW INVESTMENTS, LP$37M
- CANADA PENSION PLAN INVESTMENT BOARD$20M
- LORD, ABBETT & CO. LLC$20M
- Longaeva Partners L.P.$12M
- SCHRODER INVESTMENT MANAGEMENT GROUP$9M
Largest adds
- NORGES BANK$295M
- Avoro Capital Advisors LLC$255M
- FMR LLC$200M
- BlackRock, Inc.$199M
- VANGUARD CAPITAL MANAGEMENT LLC$120M
- Invesco Ltd.$120M
Largest trims
- D. E. Shaw & Co., Inc.$39M
- Pictet Asset Management Holding SA$33M
- RENAISSANCE TECHNOLOGIES LLC$27M
- PANAGORA ASSET MANAGEMENT INC$26M
- Alyeska Investment Group, L.P.$25M
- ARROWSTREET CAPITAL, LIMITED PARTNERSHIP$19M
Institutional holders
One row per tracked fund, most shares held first (every row is from one quarter; reported value breaks ties). “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding.
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| BlackRock, Inc. trimmed | 14,830,553 | $1.2B | 13.3% | 2026-Q2 |
| Avoro Capital Advisors LLC added | 11,355,555 | $926M | 10.2% | 2026-Q2 |
| FMR LLC added | 8,039,804 | $655M | 7.2% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC trimmed | 6,351,355 | $518M | 5.7% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 6,110,953 | $498M | 5.5% | 2026-Q2 |
| STATE STREET CORP trimmed | 5,694,640 | $464M | 5.1% | 2026-Q2 |
| NORGES BANK added | 3,896,536 | $318M | 3.5% | 2026-Q2 |
| Invesco Ltd. added | 3,883,976 | $317M | 3.5% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC trimmed | 3,530,612 | $299M | 3.3% | 2026-Q2 |
| FRED ALGER MANAGEMENT, LLC trimmed | 3,301,919 | $269M | 3.0% | 2026-Q2 |
| BAKER BROS. ADVISORS LP | 1,992,783 | $162M | 1.8% | 2026-Q2 |
| Siren, L.L.C. added | 1,715,476 | $140M | 1.5% | 2026-Q2 |
| Vestal Point Capital, LP trimmed | 1,575,000 | $128M | 1.4% | 2026-Q2 |
| DEERFIELD MANAGEMENT COMPANY, L.P. trimmed | 1,389,055 | $113M | 1.2% | 2026-Q2 |
| FIRST TRUST ADVISORS LP added | 1,352,918 | $110M | 1.2% | 2026-Q2 |
| Driehaus Capital Management LLC added | 1,350,556 | $110M | 1.2% | 2026-Q2 |
| Jupiter Topco LLC new | 1,221,596 | $100M | 1.1% | 2026-Q2 |
| NORTHERN TRUST CORP trimmed | 1,192,868 | $97M | 1.1% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP added | 1,181,608 | $96M | 1.1% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC trimmed | 1,150,007 | $94M | 1.0% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ added | 1,139,810 | $93M | 1.0% | 2026-Q2 |
| Hood River Capital Management LLC added | 1,120,747 | $91M | 1.0% | 2026-Q2 |
| Holocene Advisors, LP new | 1,106,177 | $90M | 1.0% | 2026-Q2 |
| MORGAN STANLEY added | 1,084,835 | $88M | 1.0% | 2026-Q2 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC trimmed | 964,479 | $79M | 0.9% | 2026-Q2 |
| Fisher Asset Management, LLC trimmed | 957,691 | $78M | 0.9% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC trimmed | 923,927 | $75M | 0.8% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO trimmed | 896,738 | $73M | 0.8% | 2026-Q2 |
| UBS Group AG trimmed | 861,520 | $70M | 0.8% | 2026-Q2 |
| Bank of New York Mellon Corp trimmed | 859,538 | $70M | 0.8% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ trimmed | 853,360 | $70M | 0.8% | 2026-Q2 |
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC added | 830,247 | $68M | 0.7% | 2026-Q2 |
| Western Financial Corp/CA | 820,239 | $67M | 0.7% | 2026-Q2 |
| JPMORGAN CHASE & CO trimmed | 637,399 | $52M | 0.6% | 2026-Q2 |
| Connor, Clark & Lunn Investment Management Ltd. trimmed | 625,569 | $51M | 0.6% | 2026-Q2 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP added | 596,573 | $49M | 0.5% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP added | 580,609 | $47M | 0.5% | 2026-Q2 |
| Pictet Asset Management Holding SA trimmed | 573,419 | $47M | 0.5% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS trimmed | 558,643 | $46M | 0.5% | 2026-Q2 |
| 1832 Asset Management L.P. new | 538,500 | $44M | 0.5% | 2026-Q2 |
| PRINCIPAL FINANCIAL GROUP INC added | 514,658 | $42M | 0.5% | 2026-Q2 |
| VOYA INVESTMENT MANAGEMENT LLC trimmed | 483,495 | $39M | 0.4% | 2026-Q2 |
| BALYASNY ASSET MANAGEMENT L.P. added | 470,754 | $38M | 0.4% | 2026-Q2 |
| RENAISSANCE TECHNOLOGIES LLC trimmed | 468,921 | $38M | 0.4% | 2026-Q2 |
| FRANKLIN RESOURCES INC trimmed | 462,133 | $38M | 0.4% | 2026-Q2 |
| D. E. Shaw & Co., Inc. trimmed | 431,560 | $35M | 0.4% | 2026-Q2 |
| Nuveen, LLC trimmed | 415,883 | $34M | 0.4% | 2026-Q2 |
| RHUMBLINE ADVISERS trimmed | 374,897 | $31M | 0.3% | 2026-Q2 |
| EVENTIDE ASSET MANAGEMENT, LLC | 370,000 | $30M | 0.3% | 2026-Q2 |
| AMERICAN CENTURY COMPANIES INC trimmed | 364,211 | $30M | 0.3% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC added | 329,337 | $27M | 0.3% | 2026-Q2 |
| LPL Financial LLC added | 310,761 | $25M | 0.3% | 2026-Q2 |
| Artisan Partners Limited Partnership new | 310,706 | $25M | 0.3% | 2026-Q2 |
| MARSHALL WACE, LLP added | 305,031 | $25M | 0.3% | 2026-Q2 |
| SEI INVESTMENTS CO added | 300,619 | $25M | 0.3% | 2026-Q2 |
| NORDEA INVESTMENT MANAGEMENT AB trimmed | 284,175 | $24M | 0.3% | 2026-Q2 |
| Russell Investments Group, Ltd. added | 284,096 | $23M | 0.3% | 2026-Q2 |
| CITIGROUP INC added | 264,678 | $22M | 0.2% | 2026-Q2 |
| California Public Employees Retirement System trimmed | 256,314 | $21M | 0.2% | 2026-Q2 |
| Squarepoint Ops LLC added | 255,907 | $21M | 0.2% | 2026-Q2 |
| ENVESTNET ASSET MANAGEMENT INC added | 254,228 | $21M | 0.2% | 2026-Q2 |
| Aberdeen Group plc trimmed | 251,968 | $21M | 0.2% | 2026-Q2 |
| Swiss National Bank trimmed | 238,900 | $19M | 0.2% | 2026-Q2 |
| Legal & General Group Plc added | 237,216 | $19M | 0.2% | 2026-Q2 |
| Privium Fund Management B.V. trimmed | 234,222 | $19M | 0.2% | 2026-Q2 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP trimmed | 218,133 | $18M | 0.2% | 2026-Q2 |
| Life Cycle Investment Partners Ltd new | 209,068 | $17M | 0.2% | 2026-Q2 |
| HSBC HOLDINGS PLC added | 203,800 | $17M | 0.2% | 2026-Q2 |
| Assenagon Asset Management S.A. added | 201,927 | $16M | 0.2% | 2026-Q2 |
| Woodline Partners LP | 200,184 | $16M | 0.2% | 2026-Q2 |
| Integral Health Asset Management, LLC trimmed | 200,000 | $16M | 0.2% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC added | 198,842 | $16M | 0.2% | 2026-Q2 |
| JANE STREET GROUP, LLC added | 196,205 | $16M | 0.2% | 2026-Q2 |
| MUTUAL OF AMERICA CAPITAL MANAGEMENT LLC added | 191,432 | $16M | 0.2% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. trimmed | 173,265 | $11M | 0.1% | 2026-Q2 |
| WCM INVESTMENT MANAGEMENT, LLC trimmed | 171,232 | $14M | 0.2% | 2026-Q2 |
| PINNACLE ASSOCIATES LTD trimmed | 170,131 | $14M | 0.2% | 2026-Q2 |
| RAYMOND JAMES FINANCIAL INC trimmed | 169,913 | $14M | 0.2% | 2026-Q2 |
| SEB Asset Management AB | 158,205 | $13M | 0.1% | 2026-Q2 |
| Clearbridge Investments, LLC trimmed | 157,110 | $13M | 0.1% | 2026-Q2 |
| AMERIPRISE FINANCIAL INC trimmed | 155,908 | $13M | 0.1% | 2026-Q2 |
| Affinity Asset Advisors, LLC trimmed | 150,000 | $12M | 0.1% | 2026-Q2 |
| DEUTSCHE BANK AG\ trimmed | 149,240 | $12M | 0.1% | 2026-Q2 |
| WEALTH EFFECTS LLC added | 147,300 | $12M | 0.1% | 2026-Q2 |
| Retirement Systems of Alabama trimmed | 145,687 | $12M | 0.1% | 2026-Q2 |
| TORONTO DOMINION BANK trimmed | 144,928 | $12M | 0.1% | 2026-Q2 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM trimmed | 139,826 | $11M | 0.1% | 2026-Q2 |
| Weiss Asset Management LP added | 134,014 | $11M | 0.1% | 2026-Q2 |
| BANK OF NOVA SCOTIA trimmed | 133,805 | $11M | 0.1% | 2026-Q2 |
| PFM Health Sciences, LP added | 131,667 | $11M | 0.1% | 2026-Q2 |
| Tetragon Partners GP Ltd added | 130,484 | $11M | 0.1% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN trimmed | 128,789 | $10M | 0.1% | 2026-Q2 |
| Rhenman & Partners Asset Management AB trimmed | 128,000 | $10M | 0.1% | 2026-Q2 |
| VANGUARD ASSET MANAGEMENT, Ltd added | 119,102 | $10M | 0.1% | 2026-Q2 |
| Catalyst Funds Management Pty Ltd new | 117,600 | $10M | 0.1% | 2026-Q2 |
| Universal- Beteiligungs- und Servicegesellschaft mbH trimmed | 116,393 | $9M | 0.1% | 2026-Q2 |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE trimmed | 111,955 | $9M | 0.1% | 2026-Q2 |
| VAN ECK ASSOCIATES CORP added | 111,500 | $9M | 0.1% | 2026-Q2 |
| ACT CAPITAL MANAGEMENT, LLC added | 110,100 | $9M | 0.1% | 2026-Q2 |
| Empowered Funds, LLC trimmed | 108,041 | $9M | 0.1% | 2026-Q2 |
Ownership over time
Tracked institutional holder count and total shares held by filing quarter (independent scales). The curated-era tail and any mid-ingest latest quarter are handled honestly — a partial quarter is not drawn as a collapse.
Reading this table
Funds hold the same stock for different reasons — an index fund “holds” almost everything, an active manager sizes a name to a mandate and a benchmark, and each fund entered at its own price and time. Because 13F is filed up to 45 days after quarter-end, every row is a backward-looking snapshot; a manager may have traded since. Share-class siblings (a company’s A and C shares) are rolled up to one line so a dual-class name is never double-counted. Compare like-for-like. A large holder is not an endorsement, and a fund exiting is not a warning — this is a starting question, not a verdict.
About 13F filings
A Form 13F is a quarterly disclosure that institutional investment managers with over $100 million in US-listed equities must file with the SEC. In plain English: it is a snapshot of the long stock positions a fund held at the end of a quarter. It covers long US-listed equities only — not short positions, options, cash, or private holdings — and the funds shown are the large sample we track, not the complete 13F universe.