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 495 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	$1.90B 24,072,101 shares	0.10%	+383.06K(+1.60%)Added	SEC filing ↗ Feb 17, 2026	▾
02	Capital World Investors CIK 1422849 · View history	$1.42B 17,961,299 shares	0.19%	+5.24M(+41.20%)Added	SEC filing ↗ Feb 11, 2026	▾
03	VANGUARD GROUP INC CIK 102909 · View history	$1.30B 16,440,459 shares	0.02%	-41.27K(-0.30%)Reduced	SEC filing ↗ Jan 29, 2026	▾
04	BlackRock, Inc. CIK 2012383 · View history	$842.35M 10,647,863 shares	0.01%	+199.92K(+1.90%)Added	SEC filing ↗ Feb 12, 2026	▾
05	T. Rowe Price Investment Management, Inc. CIK 1897612 · Amended · View history	$720.54M 9,108,019 shares	0.45%	-4.05M(-30.80%)Reduced	SEC filing ↗ Feb 19, 2026	▾
06	WELLINGTON MANAGEMENT GROUP LLP CIK 902219 · View history	$495.25M 6,260,325 shares	0.09%	-328.49K(-5.00%)Reduced	SEC filing ↗ Feb 17, 2026	▾
07	Bellevue Group AG CIK 1674546 · View history	$379.90M 4,802,199 shares	7.20%	-1.44M(-23.10%)Reduced	SEC filing ↗ Feb 17, 2026	▾
08	STATE STREET CORP CIK 93751 · View history	$314.45M 3,974,865 shares	0.01%	-413.79K(-9.40%)Reduced	SEC filing ↗ Feb 13, 2026	▾
09	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$249.16M 3,148,849 shares	0.02%	+82.56K(+2.70%)Added	SEC filing ↗ Feb 9, 2026	▾
10	TWO SIGMA ADVISERS, LP CIK 1478735 · View history	$241.45M 3,052,111 shares	0.47%	+979.00K(+47.20%)Added	SEC filing ↗ Feb 17, 2026	▾
11	PRICE T ROWE ASSOCIATES INC /MD/ CIK 80255 · View history	$236.37M 2,987,840 shares	0.03%	+258.15K(+9.50%)Added	SEC filing ↗ Feb 17, 2026	▾
12	TWO SIGMA INVESTMENTS, LP CIK 1179392 · View history	$210.33M 2,658,646 shares	0.31%	+1.08M(+68.70%)Added	SEC filing ↗ Feb 17, 2026	▾
13	Tweedy, Browne Co LLC CIK 732905 · View history	$195.00M 2,464,930 shares	15.74%	-436.29K(-15.00%)Reduced	SEC filing ↗ Feb 3, 2026	▾
14	JPMORGAN CHASE & CO CIK 19617 · View history	$182.33M 2,304,792 shares	0.01%	+1.76M(+323.30%)Added	SEC filing ↗ Feb 11, 2026	▾
15	CITADEL ADVISORS LLC CIK 1423053 · View history	$168.87M 2,134,636 shares	0.11%	-267.43K(-11.10%)Reduced	SEC filing ↗ Feb 17, 2026	▾
16	DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) CIK 1009258 · View history	$156.61M 1,979,669 shares	2.01%	0(0.00%)Unchanged	SEC filing ↗ Feb 17, 2026	▾
17	BAKER BROS. ADVISORS LP CIK 1263508 · View history	$141.75M 1,791,841 shares	0.83%	+1.23M(+216.10%)Added	SEC filing ↗ Feb 17, 2026	▾
18	Deep Track Capital, LP CIK 1856083 · View history	$134.49M 1,700,000 shares	3.07%	-2.11M(-55.40%)Reduced	SEC filing ↗ Feb 13, 2026	▾
19	AMERICAN CENTURY COMPANIES INC CIK 748054 · View history	$127.93M 1,617,106 shares	0.06%	+244.88K(+17.80%)Added	SEC filing ↗ Feb 13, 2026	▾
20	CHARLES SCHWAB INVESTMENT MANAGEMENT INC CIK 884546 · View history	$121.98M 1,541,841 shares	0.02%	+21.89K(+1.40%)Added	SEC filing ↗ Feb 13, 2026	▾

Showing 20 / 495 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

495

Cancelled or null records excluded

Disclosed shares

170,227,106

Not deduplicated across managers

Disclosed value

$13.46B

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 · Q4 2025

Explore all 495 reporting institutions.

This page includes 20 of 495 reporting institutions. Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

Download CSV
Earlier quarters
Advanced screening & filtering
API & AI access

Already have an account?

＋ New accounts get free API credits to explore data beyond ownership filings.

For AI agents & developers

The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. This page lists 20 of 495 reporting institutions; totals use the complete disclosed data.

Without an account: the last 3 years, with the row caps stated on the page. A free account opens all history on file on these pages and the CSV of what a page shows. Rows beyond the caps and bulk retrieval go through the authenticated API / MCP / CLI.

MCP  https://api.akkrudata.ai/mcp

akkru_institutional_holdings
{"action":"holders","cusip":"462222100","quarter":"2025Q4","type":"positions","page_size":100}

Connect to MCP with OAuth and follow the returned pagination. Credits and usage limits depend on the account.

MCP endpoint: https://api.akkrudata.ai/mcp
API / MCP / CLI documentation: /documents
llms.txt: /llms.txt

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.