Skip to main content
Institutional Ownership · SEC Form 13F

Who owns Ionis Pharmaceuticals (IONS)


Which tracked institutional funds hold IONS, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See IONS 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.

488
Institutional holders
188M
Shares held (tracked funds)

How the tape is positioned

152 tracked funds added or opened IONS while 103 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

IONS’s largest tracked holder by dollar value, FMR LLC, sizes it at 0.1% of its own reported 13F book, while the median holder sizes it at 0.1% of theirs — a 0.0pp conviction gap — its largest holder concentrates the name more heavily than the typical one.

Book-share is each fund’s reported value in IONS 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 483 tracked filers holding IONS, 245 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 IONS 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 21

  • Capital International Investors$65M
  • Freestone Grove Partners LP$27M
  • Life Cycle Investment Partners Ltd$17M
  • Eagle Health Investments LP$15M
  • PICTON MAHONEY ASSET MANAGEMENT$8M
  • BANK OF NOVA SCOTIA$5M

Full exits 39

  • T. Rowe Price Investment Management, Inc.$462M
  • GW&K Investment Management, LLC$59M
  • C WorldWide Group Holding A/S$27M
  • HRT FINANCIAL LP$19M
  • Zurich Insurance Group Ltd/FI$18M
  • Handelsbanken Fonder AB$16M

Largest adds

  • ROYAL BANK OF CANADA$205M
  • BlackRock, Inc.$191M
  • WELLINGTON MANAGEMENT GROUP LLP$127M
  • Capital World Investors$127M
  • FMR LLC$109M
  • BARCLAYS PLC$105M

Largest trims

  • Bellevue Group AG$59M
  • MILLENNIUM MANAGEMENT LLC$56M
  • CITADEL ADVISORS LLC$52M
  • AMERIPRISE FINANCIAL INC$44M
  • Squarepoint Ops LLC$44M
  • SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC$43M

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.

FundSharesReported value% of valueQuarter
FMR LLC added24,631,956$2.0B14.9%2026-Q2
Capital World Investors added21,669,226$1.7B13.1%2026-Q2
BlackRock, Inc. added10,704,660$849M6.5%2026-Q2
VANGUARD PORTFOLIO MANAGEMENT LLC added7,859,529$623M4.7%2026-Q2
WELLINGTON MANAGEMENT GROUP LLP added7,651,415$607M4.6%2026-Q2
VANGUARD CAPITAL MANAGEMENT LLC added7,211,497$572M4.4%2026-Q2
TWO SIGMA INVESTMENTS, LP added6,252,342$496M3.8%2026-Q2
ROYAL BANK OF CANADA added6,182,479$490M3.7%2026-Q2
STATE STREET CORP added4,334,848$344M2.6%2026-Q2
GEODE CAPITAL MANAGEMENT, LLC trimmed3,584,024$295M2.2%2026-Q2
PRICE T ROWE ASSOCIATES INC /MD/ added3,184,500$252M1.9%2026-Q2
JPMORGAN CHASE & CO added2,671,717$216M1.6%2026-Q2
Artisan Partners Limited Partnership added2,640,024$209M1.6%2026-Q2
Tweedy, Browne Co LLC added2,280,311$181M1.4%2026-Q2
Deep Track Capital, LP added2,200,000$174M1.3%2026-Q2
GOLDMAN SACHS GROUP INC added2,109,945$167M1.3%2026-Q2
BAKER BROS. ADVISORS LP2,047,727$162M1.2%2026-Q2
DEERFIELD MANAGEMENT COMPANY, L.P.1,979,669$157M1.2%2026-Q2
AMERICAN CENTURY COMPANIES INC added1,947,076$154M1.2%2026-Q2
FRANKLIN RESOURCES INC added1,623,377$129M1.0%2026-Q2
CHARLES SCHWAB INVESTMENT MANAGEMENT INC added1,605,054$127M1.0%2026-Q2
BARCLAYS PLC added1,603,136$127M1.0%2026-Q2
Pictet Asset Management Holding SA added1,596,998$127M1.0%2026-Q2
UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC trimmed1,454,672$115M0.9%2026-Q2
Polar Capital Holdings Plc added1,454,021$115M0.9%2026-Q2
Alyeska Investment Group, L.P. added1,417,916$112M0.9%2026-Q2
NOMURA ASSET MANAGEMENT INTERNATIONAL INC. added1,300,392$103M0.8%2026-Q2
MORGAN STANLEY added1,281,444$102M0.8%2026-Q2
Invesco Ltd. trimmed1,120,707$89M0.7%2026-Q2
VANGUARD FIDUCIARY TRUST CO added1,060,845$84M0.6%2026-Q2
Bellevue Group AG trimmed972,258$77M0.6%2026-Q2
GROUPAMA ASSET MANAGMENT added937,083$75M0.6%2026-Q2
NORTHERN TRUST CORP added913,610$72M0.6%2026-Q2
Capital International Investors new823,764$65M0.5%2026-Q2
Davern Capital Partners, LP added798,709$63M0.5%2026-Q2
BANK OF AMERICA CORP /DE/ trimmed790,990$63M0.5%2026-Q2
SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC trimmed787,263$62M0.5%2026-Q2
BNP PARIBAS ASSET MANAGEMENT Holding S.A. trimmed734,219$58M0.4%2026-Q2
Nuveen, LLC added726,282$58M0.4%2026-Q2
Connor, Clark & Lunn Investment Management Ltd. trimmed684,236$54M0.4%2026-Q2
Eversept Partners, LP added664,684$53M0.4%2026-Q2
VOLORIDGE INVESTMENT MANAGEMENT, LLC trimmed655,454$52M0.4%2026-Q2
MASSACHUSETTS FINANCIAL SERVICES CO /MA/ trimmed651,816$52M0.4%2026-Q2
NEUBERGER BERMAN GROUP LLC added633,533$50M0.4%2026-Q2
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP trimmed632,028$50M0.4%2026-Q2
UBS Group AG trimmed624,874$50M0.4%2026-Q2
TimesSquare Capital Management, LLC added614,070$49M0.4%2026-Q2
EVENTIDE ASSET MANAGEMENT, LLC575,000$46M0.3%2026-Q2
PERCEPTIVE ADVISORS LLC added566,000$45M0.3%2026-Q2
RENAISSANCE TECHNOLOGIES LLC added559,414$44M0.3%2026-Q2
Bank of New York Mellon Corp added542,454$43M0.3%2026-Q2
TEACHER RETIREMENT SYSTEM OF TEXAS trimmed522,317$41M0.3%2026-Q2
BOONE CAPITAL MANAGEMENT LLC added519,977$41M0.3%2026-Q2
JANE STREET GROUP, LLC added503,647$40M0.3%2026-Q2
NEW YORK STATE COMMON RETIREMENT FUND added500,050$40M0.3%2026-Q2
BNP PARIBAS FINANCIAL MARKETS trimmed454,649$36M0.3%2026-Q2
Candriam S.C.A. trimmed445,019$35M0.3%2026-Q2
FIRST TRUST ADVISORS LP trimmed427,197$34M0.3%2026-Q2
PINNACLE ASSOCIATES LTD trimmed419,752$33M0.3%2026-Q2
NOMURA HOLDINGS INC added402,192$32M0.2%2026-Q2
TD Asset Management Inc trimmed340,548$27M0.2%2026-Q2
ALLIANCEBERNSTEIN L.P. trimmed340,450$26M0.2%2026-Q2
Freestone Grove Partners LP new339,967$27M0.2%2026-Q2
Qube Research & Technologies Ltd added333,952$26M0.2%2026-Q2
Capital Research Global Investors added331,936$26M0.2%2026-Q2
CAPITAL FUND MANAGEMENT S.A. added329,554$26M0.2%2026-Q2
Carmignac Gestion added321,000$25M0.2%2026-Q2
Privium Fund Management B.V. added319,924$25M0.2%2026-Q2
Swiss National Bank added315,000$25M0.2%2026-Q2
Jump Financial, LLC added306,330$24M0.2%2026-Q2
ARK Investment Management LLC added300,770$24M0.2%2026-Q2
Legal & General Group Plc added299,184$24M0.2%2026-Q2
D. E. Shaw & Co., Inc. trimmed297,041$24M0.2%2026-Q2
MILLENNIUM MANAGEMENT LLC trimmed288,872$23M0.2%2026-Q2
DAVENPORT & Co LLC added283,960$23M0.2%2026-Q2
Aberdeen Group plc added277,400$22M0.2%2026-Q2
California Public Employees Retirement System added270,843$21M0.2%2026-Q2
TOCQUEVILLE ASSET MANAGEMENT L.P. added251,215$20M0.2%2026-Q2
RAYMOND JAMES FINANCIAL INC added237,348$19M0.1%2026-Q2
CITADEL ADVISORS LLC trimmed236,284$19M0.1%2026-Q2
Universal- Beteiligungs- und Servicegesellschaft mbH added233,499$19M0.1%2026-Q2
WELLS FARGO & COMPANY/MN added226,213$18M0.1%2026-Q2
Empowered Funds, LLC added223,142$18M0.1%2026-Q2
Orion Investment Co trimmed220,335$17M0.1%2026-Q2
Life Cycle Investment Partners Ltd new219,896$17M0.1%2026-Q2
ALGERT GLOBAL LLC added206,853$16M0.1%2026-Q2
STIFEL FINANCIAL CORP added202,983$16M0.1%2026-Q2
Corient Private Wealth LP added196,791$16M0.1%2026-Q2
Eagle Health Investments LP new194,577$15M0.1%2026-Q2
SECTOR GAMMA AS added189,468$15M0.1%2026-Q2
HSBC HOLDINGS PLC added188,402$15M0.1%2026-Q2
CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM added180,949$14M0.1%2026-Q2
Polymer Capital Management (HK) LTD added177,897$14M0.1%2026-Q2
DEUTSCHE BANK AG\ added169,614$13M0.1%2026-Q2
ADAR1 Capital Management, LLC added166,286$13M0.1%2026-Q2
RHUMBLINE ADVISERS trimmed164,911$13M0.1%2026-Q2
Sicart Associates LLC added160,694$13M0.1%2026-Q2
VANGUARD ASSET MANAGEMENT, Ltd added155,088$12M0.1%2026-Q2
CSS LLC/IL added152,289$12M0.1%2026-Q2
DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main trimmed151,301$12M0.1%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.

HoldersTotal shares

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.

Learn how to read institutional ownership