Company · Ownership research

IONIS PHARMACEUTICALS INC IONS

CIK 0000874015 · CUSIP 462222100

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 462222100 (IONS), not CUSIP 462222900 (IONS), CUSIP 462222950 (IONS), and does not merge CUSIPs.

This page lists the top 20 of 438 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

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	FMR LLC CIK 315066 · View history	$1.55B 23,689,038 shares	0.08%	+46.05K(+0.20%)Added	SEC filing ↗ Nov 13, 2025	▾
02	VANGUARD GROUP INC CIK 102909 · View history	$1.08B 16,481,730 shares	0.02%	-233.12K(-1.40%)Reduced	SEC filing ↗ Nov 7, 2025	▾
03	T. Rowe Price Investment Management, Inc. CIK 1897612 · View history	$860.73M 13,156,929 shares	0.53%	-2.89M(-18.00%)Reduced	SEC filing ↗ Nov 14, 2025	▾
04	Capital World Investors CIK 1422849 · View history	$832.32M 12,722,728 shares	0.11%	+182.54K(+1.50%)Added	SEC filing ↗ Nov 13, 2025	▾
05	BlackRock, Inc. CIK 2012383 · View history	$683.50M 10,447,940 shares	0.01%	-449.00K(-4.10%)Reduced	SEC filing ↗ Nov 12, 2025	▾
06	WELLINGTON MANAGEMENT GROUP LLP CIK 902219 · View history	$431.04M 6,588,811 shares	0.08%	+243.03K(+3.80%)Added	SEC filing ↗ Nov 14, 2025	▾
07	Bellevue Group AG CIK 1674546 · View history	$408.51M 6,244,451 shares	8.49%	-1.61M(-20.50%)Reduced	SEC filing ↗ Nov 14, 2025	▾
08	STATE STREET CORP CIK 93751 · View history	$287.11M 4,388,651 shares	0.01%	-141.75K(-3.10%)Reduced	SEC filing ↗ Nov 14, 2025	▾
09	Deep Track Capital, LP CIK 1856083 · View history	$249.13M 3,808,144 shares	6.95%	-1.08M(-22.10%)Reduced	SEC filing ↗ Nov 14, 2025	▾
10	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$200.63M 3,066,289 shares	0.01%	+175.19K(+6.10%)Added	SEC filing ↗ Nov 12, 2025	▾
11	Tweedy, Browne Co LLC CIK 732905 · View history	$189.80M 2,901,216 shares	16.48%	+9.27K(+0.30%)Added	SEC filing ↗ Nov 20, 2025	▾
12	PRICE T ROWE ASSOCIATES INC /MD/ CIK 80255 · View history	$178.58M 2,729,685 shares	0.02%	-396.39K(-12.70%)Reduced	SEC filing ↗ Nov 14, 2025	▾
13	CITADEL ADVISORS LLC CIK 1423053 · View history	$157.14M 2,402,065 shares	0.13%	+907.08K(+60.70%)Added	SEC filing ↗ Nov 14, 2025	▾
14	TWO SIGMA ADVISERS, LP CIK 1478735 · View history	$135.62M 2,073,111 shares	0.27%	-594.50K(-22.30%)Reduced	SEC filing ↗ Nov 14, 2025	▾
15	DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) CIK 1009258 · View history	$129.51M 1,979,669 shares	1.98%	+1.98MNew	SEC filing ↗ Nov 14, 2025	▾
16	TWO SIGMA INVESTMENTS, LP CIK 1179392 · View history	$103.10M 1,575,943 shares	0.16%	-212.42K(-11.90%)Reduced	SEC filing ↗ Nov 14, 2025	▾
17	CHARLES SCHWAB INVESTMENT MANAGEMENT INC CIK 884546 · View history	$99.44M 1,519,951 shares	0.02%	+32.13K(+2.20%)Added	SEC filing ↗ Nov 10, 2025	▾
18	Pictet Asset Management Holding SA CIK 1993888 · View history	$90.48M 1,393,124 shares	0.09%	+784.48K(+128.90%)Added	SEC filing ↗ Nov 18, 2025	▾
19	AMERICAN CENTURY COMPANIES INC CIK 748054 · View history	$89.77M 1,372,225 shares	0.05%	+899.48K(+190.30%)Added	SEC filing ↗ Nov 12, 2025	▾
20	ADAGE CAPITAL PARTNERS GP, L.L.C. CIK 1165408 · View history	$86.03M 1,315,000 shares	0.14%	-2.48M(-65.40%)Reduced	SEC filing ↗ Nov 14, 2025	▾

Showing 20 / 438 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

438

Cancelled or null records excluded

Disclosed shares

175,157,384

Not deduplicated across managers

Disclosed value

$11.01B

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.

IONIS PHARMACEUTICALS INC · Q3 2025

Explore all 438 reporting institutions.

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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.