Company · Ownership research

ARROWHEAD PHARMACEUTICALS, INC. ARWR

CIK 0000879407 · CUSIP 04280A100

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 04280A100 (ARWR), not CUSIP 04280A900 (ARWR), CUSIP 04280A950 (ARWR), and does not merge CUSIPs.

This page lists the top 20 of 402 rows by value; the complete set is available through the API.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	BlackRock, Inc. CIK 2012383 · View history	$1.42B 21,318,582 shares	0.02%	+1.09M(+5.40%)Added	SEC filing ↗ Feb 12, 2026	▾
02	VANGUARD GROUP INC CIK 102909 · View history	$1.02B 15,293,121 shares	0.01%	-742.75K(-4.60%)Reduced	SEC filing ↗ Jan 29, 2026	▾
03	Avoro Capital Advisors LLC CIK 1633313 · Amended · View history	$705.39M 10,625,000 shares	6.93%	-275.00K(-2.50%)Reduced	SEC filing ↗ Mar 16, 2026	▾
04	FMR LLC CIK 315066 · View history	$432.89M 6,520,408 shares	0.02%	+760.58K(+13.20%)Added	SEC filing ↗ Feb 17, 2026	▾
05	STATE STREET CORP CIK 93751 · View history	$425.15M 6,403,830 shares	0.01%	+6.47K(+0.10%)Added	SEC filing ↗ Feb 13, 2026	▾
06	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$216.80M 3,264,963 shares	0.01%	+133.92K(+4.30%)Added	SEC filing ↗ Feb 9, 2026	▾
07	Slate Path Capital LP CIK 1559706 · View history	$167.54M 2,523,500 shares	2.26%	-2.46M(-49.30%)Reduced	SEC filing ↗ Feb 17, 2026	▾
08	BAKER BROS. ADVISORS LP CIK 1263508 · View history	$144.44M 2,175,645 shares	0.85%	+504.88K(+30.20%)Added	SEC filing ↗ Feb 17, 2026	▾
09	ARROWSTREET CAPITAL, LIMITED PARTNERSHIP CIK 1164508 · View history	$138.62M 2,087,953 shares	0.08%	+6.26K(+0.30%)Added	SEC filing ↗ Feb 13, 2026	▾
10	FRED ALGER MANAGEMENT, LLC CIK 3520 · View history	$121.69M 1,832,997 shares	0.48%	+1.53M(+497.40%)Added	SEC filing ↗ Feb 17, 2026	▾
11	DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) CIK 1009258 · View history	$121.69M 1,832,946 shares	1.56%	+839.95K(+84.60%)Added	SEC filing ↗ Feb 17, 2026	▾
12	Driehaus Capital Management LLC CIK 938206 · View history	$117.47M 1,769,340 shares	0.80%	-330.06K(-15.70%)Reduced	SEC filing ↗ Feb 17, 2026	▾
13	NORGES BANK CIK 1374170 · View history	$113.16M 1,704,464 shares	0.01%	+1.70MNew	SEC filing ↗ Feb 10, 2026	▾
14	GOLDMAN SACHS GROUP INC CIK 886982 · Amended · View history	$111.37M 1,677,522 shares	0.02%	-96.36K(-5.40%)Reduced	SEC filing ↗ Mar 25, 2026	▾
15	Siren, L.L.C. CIK 2005245 · View history	$99.62M 1,500,476 shares	2.97%	-1.17M(-43.80%)Reduced	SEC filing ↗ Feb 13, 2026	▾
16	MORGAN STANLEY CIK 895421 · Amended · View history	$97.99M 1,476,005 shares	0.01%	-226.67K(-13.30%)Reduced	SEC filing ↗ May 27, 2026	▾
17	CHARLES SCHWAB INVESTMENT MANAGEMENT INC CIK 884546 · View history	$89.87M 1,353,719 shares	0.01%	+7.86K(+0.60%)Added	SEC filing ↗ Feb 13, 2026	▾
18	NORTHERN TRUST CORP CIK 73124 · View history	$89.38M 1,346,257 shares	0.01%	+34.67K(+2.60%)Added	SEC filing ↗ Feb 17, 2026	▾
19	Fisher Asset Management, LLC CIK 850529 · View history	$87.09M 1,311,727 shares	0.03%	+257.93K(+24.50%)Added	SEC filing ↗ Feb 9, 2026	▾
20	JANUS HENDERSON GROUP PLC CIK 1274173 · View history	$85.00M 1,280,446 shares	0.04%	+306.88K(+31.50%)Added	SEC filing ↗ Feb 17, 2026	▾

Showing 20 / 402 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

402

Cancelled or null records excluded

Disclosed shares

116,004,650

Not deduplicated across managers

Disclosed value

$7.70B

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

ARROWHEAD PHARMACEUTICALS, INC. · Q4 2025

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Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.