IONIS PHARMACEUTICALS INC IONS
COM · Common Stock · CUSIP 462222100 · ISIN US4622221004
American pharmaceutical company
- SectorHealth care
- IndustryPharmaceutical Preparations
- HeadquartersCarlsbad, CA
- Founded1989
- Websiteionispharma.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($56.2m this quarter). Holder counts are more reliable. Shares outstanding: 166.2m as of 2026-07-23, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $79.38. Options: 29 managers hold calls ($395.4m notional), 19 hold puts ($250.1m).
Trends to Q2 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 350 |
| Q4 2022 | 339 |
| Q1 2023 | 316 |
| Q2 2023 | 307 |
| Q3 2023 | 313 |
| Q4 2023 | 366 |
| Q1 2024 | 362 |
| Q2 2024 | 358 |
| Q3 2024 | 357 |
| Q4 2024 | 359 |
| Q1 2025 | 348 |
| Q2 2025 | 366 |
| Q3 2025 | 439 |
| Q4 2025 | 494 |
| Q1 2026 | 497 |
| Q2 2026 | 513 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q3 2024 | 176 | 159 |
| Q4 2024 | 160 | 169 |
| Q1 2025 | 150 | 184 |
| Q2 2025 | 197 | 169 |
| Q3 2025 | 245 | 152 |
| Q4 2025 | 261 | 186 |
| Q1 2026 | 241 | 223 |
| Q2 2026 | 263 | 205 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q3 2025 | $171.8m | $74.8m | 0.44 |
| Q4 2025 | $149.5m | $102.3m | 0.68 |
| Q1 2026 | $141.4m | $144.3m | 1.02 |
| Q2 2026 | $395.4m | $250.1m | 0.63 |
Biggest buyers
| ROYAL BANK OF CANADA | Added | +2.4m |
| BARCLAYS PLC | Added | +1.3m |
| WELLINGTON MANAGEMENT GROUP LLP | Added | +1.3m |
| Alyeska Investment Group, L.P. | Added | +944.8k |
| Capital International Investors | New | +823.8k |
| Polar Capital Holdings Plc | Added | +624.5k |
| Artisan Partners Limited Partnership | Added | +581.7k |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. | Added | +515.1k |
| Capital World Investors | Added | +482.9k |
| Davern Capital Partners, LP | Added | +411.8k |
Biggest sellers
| T. Rowe Price Investment Management, Inc. | Reduced | -2.2m |
| Bellevue Group AG | Reduced | -846.4k |
| MILLENNIUM MANAGEMENT LLC | Reduced | -762.6k |
| CITADEL ADVISORS LLC | Reduced | -706.2k |
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC | Reduced | -616.8k |
| AMERIPRISE FINANCIAL INC | Reduced | -592.4k |
| Squarepoint Ops LLC | Reduced | -585.9k |
| GEODE CAPITAL MANAGEMENT, LLC | Reduced | -400.3k |
| Zurich Insurance Group Ltd/FI | Sold out | -239.6k |
| J. Goldman & Co LP | Reduced | -194.9k |
Biggest calls
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $103.1m1.3m shares |
| Caption Management, LLC | New | $50.0m630.0k shares |
| JANE STREET GROUP, LLC | Added | $44.0m555.5k shares |
| Ikarian Capital, LLC | Added | $31.7m400.0k shares |
| Integral Health Asset Management, LLC | New | $23.8m300.0k shares |
| MILLENNIUM MANAGEMENT LLC | New | $20.4m257.5k shares |
| CITADEL ADVISORS LLC | Added | $18.4m232.5k shares |
| JPMORGAN CHASE & CO | Unchanged | $13.3m165.0k shares |
| CITIGROUP INC | Added | $12.0m151.3k shares |
| IMC-Chicago, LLC | Added | $10.1m127.8k shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $65.2m822.1k shares |
| JANE STREET GROUP, LLC | Added | $43.1m543.2k shares |
| CITADEL ADVISORS LLC | Added | $30.6m386.5k shares |
| Caption Management, LLC | New | $27.4m345.9k shares |
| Ikarian Capital, LLC | New | $23.8m300.0k shares |
| JPMORGAN CHASE & CO | Unchanged | $13.3m165.0k shares |
| IMC-Chicago, LLC | Added | $9.9m124.9k shares |
| BOOTHBAY FUND MANAGEMENT, LLC | New | $7.3m92.1k shares |
| SIG BROKERAGE, LP | Added | $6.5m82.5k shares |
| SIMPLEX TRADING, LLC | Added | $5.1m64.9k shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| Capital World Investors 13G · institution +1.7 pts · filed 2026-05-14 | 12.8% |
| BlackRock, Inc. 13G · institution filed 2025-04-17 | 5.7% |
| VANGUARD CAPITAL MANAGEMENT LLC 13G · institution new · filed 2026-04-30 | 5.0% |
Fell to 5% or below in the last year: T. Rowe Price Investment Management, Inc. (3.7%, 2026-05-15), VANGUARD GROUP INC (0.0%, 2026-03-27; now reported by VANGUARD CAPITAL MANAGEMENT LLC)
Insider purchases and sales since 1 Apr 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q4 2024 | 1 | $181.1k | 3 | $811.0k | $809.0k |
| Q1 2025 | 0 | — | 10 | $5.2m | $1.5m |
| Q2 2025 | 1 | $477.9k | 3 | $216.4k | — |
| Q3 2025 | 0 | — | 14 | $42.6m | $29.3m |
| Q4 2025 | 0 | — | 12 | $26.8m | $23.7m |
| Q1 2026 | 0 | — | 15 | $75.8m | $57.6m |
| Q2 2026 | 0 | — | 13 | $26.5m | $25.7m |
| Q3 2026 | 1 | $1.1m | 4 | $3.5m | $3.5m |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2026-07-31 | Hayden Michael R Director · by Spouse | Bought | $258.0k5.0k shares |
| 2026-07-30 | Hayden Michael R Director · by Spouse | Bought | $800.7k15.0k shares |
| 2026-07-07 | BENNETT C FRANK EVP, Chief Scientific Officer | Sold plan | $1.3m15.0k shares |
| 2026-07-07 | Diaz Allene M. Director | Sold plan | $863.7k10.1k shares |
| 2026-07-07 | BENNETT C FRANK EVP, Chief Scientific Officer | Sold plan | $462.7k5.5k shares |
| 2026-07-07 | Kordasiewicz Holly B. EVP, Chief Development Officer | Sold plan | $30.5k362 shares |
| 2026-07-01 | KLEIN JOSEPH III Director | Sold plan | $910.4k11.5k shares |
| 2026-06-26 | Monia Brett P Chief Executive Officer, director | Sold plan | $4.0m50.0k shares |
| 2026-06-26 | Schneider Eugene EVP, Chf Clinical Develop Ofcr | Sold plan | $2.1m26.0k shares |
| 2026-06-26 | Baroldi Joseph EVP, Chief Business Officer · by Spouse | Sold plan | $451.7k5.6k shares |
| 2026-06-26 | O'NEIL PATRICK R. EVP CLO & General Counsel | Sold plan | $245.5k3.1k shares |
| 2026-06-25 | Monia Brett P Chief Executive Officer, director | Sold plan | $1.7m21.1k shares |
| 2026-06-25 | Swayze Eric EVP Research | Sold plan | $839.5k10.6k shares |
| 2026-06-24 | Monia Brett P Chief Executive Officer, director | Sold plan | $1.1m14.6k shares |
| 2026-06-15 | BERTHELSEN SPENCER R Director | Sold plan | $587.9k8.0k shares |
| 2026-06-12 | Kordasiewicz Holly B. EVP, Chief Development Officer | Sold plan | $4.5m60.8k shares |
| 2026-06-01 | BERTHELSEN SPENCER R Director | Sold plan | $605.4k8.0k shares |
| 2026-05-14 | Monia Brett P Chief Executive Officer, director | Sold plan | $253.3k3.2k shares |
| 2026-05-13 | Monia Brett P Chief Executive Officer, director | Sold plan | $102.7k1.3k shares |
| 2026-05-04 | LOSCALZO JOSEPH Director | Sold plan | $5.8m77.3k shares |
| 2026-05-01 | KLEIN JOSEPH III Director | Sold plan | $743.2k10.1k shares |
| 2026-04-28 | Baroldi Joseph EVP, Chief Business Officer | Sold plan | $116.7k1.6k shares |
| 2026-04-16 | Baroldi Joseph EVP, Chief Business Officer | Sold | $419.0k5.6k shares |
| 2026-04-16 | Jenne Kyle EVP, Chf GL Pdt Str Ofcr | Sold | $368.5k4.9k shares |
| 2026-04-16 | Birchler Brian EVP, Corp and Development Ops | Sold | $73.0k973 shares |
| 2026-04-15 | PARSHALL B LYNNE Director | Sold plan | $381.4k5.0k shares |
| 2026-04-02 | Devers Shannon L. EVP, Chief Human Resources Ofc | Sold plan | $458.6k6.2k shares |
| 2026-04-01 | KLEIN JOSEPH III Director | Sold plan | $1.7m22.3k shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q2 2026
| Manager | Shares | Change |
|---|---|---|
| FMR LLC 0.08% of their portfolio | 24.6m $2.0bn | Added +75.3k |
| Capital World Investors 0.20% of their portfolio | 21.7m $1.7bn | Added +482.9k |
| BlackRock, Inc. 0.01% of their portfolio | 10.7m $848.8m | Added +262.2k |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.03% of their portfolio | 7.9m $623.2m | Added +50.6k |
| WELLINGTON MANAGEMENT GROUP LLP 0.10% of their portfolio | 7.7m $606.7m | Added +1.3m |
| VANGUARD CAPITAL MANAGEMENT LLC 0.01% of their portfolio | 7.2m $571.8m | Added +93.2k |
| TWO SIGMA INVESTMENTS, LP 0.37% of their portfolio | 6.3m $495.7m | Added +394.7k |
| ROYAL BANK OF CANADA 0.08% of their portfolio | 6.2m $490.2m | Added +2.4m |
| STATE STREET CORP 0.01% of their portfolio | 4.3m $343.7m | Added +339.3k |
| T. Rowe Price Investment Management, Inc. 0.21% of their portfolio | 4.0m $313.9m | Reduced -2.2m |
| GEODE CAPITAL MANAGEMENT, LLC 0.02% of their portfolio | 3.6m $294.8m | Reduced -400.3k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.03% of their portfolio | 3.2m $252.5m | Added +159.2k |
| JPMORGAN CHASE & CO 0.01% of their portfolio | 2.7m $216.2m | Added +308.1k |
| Artisan Partners Limited Partnership 0.34% of their portfolio | 2.6m $209.3m | Added +581.7k |
| Tweedy, Browne Co LLC 13.70% of their portfolio | 2.3m $180.8m | Added +4.7k |
| Deep Track Capital, LP 2.57% of their portfolio | 2.2m $174.4m | Added +250.0k |
| GOLDMAN SACHS GROUP INC 0.02% of their portfolio | 2.1m $167.3m | Added +410.1k |
| BAKER BROS. ADVISORS LP 0.81% of their portfolio | 2.0m $162.4m | Unchanged |
| DEERFIELD MANAGEMENT COMPANY, L.P. 1.64% of their portfolio | 2.0m $157.0m | Unchanged |
| AMERICAN CENTURY COMPANIES INC 0.07% of their portfolio | 1.9m $154.4m | Added +283.3k |
| FRANKLIN RESOURCES INC 0.03% of their portfolio | 1.6m $128.7m | Added +48.4k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.02% of their portfolio | 1.6m $127.3m | Added +21.8k |
| BARCLAYS PLC 0.04% of their portfolio | 1.6m $127.1m | Added +1.3m |
| Pictet Asset Management Holding SA 0.12% of their portfolio | 1.6m $127.0m | Added +162.0k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.02% of their portfolio | 1.5m $115.3m | Reduced -21.0k |
| Polar Capital Holdings Plc 0.33% of their portfolio | 1.5m $115.3m | Added +624.5k |
| Alyeska Investment Group, L.P. 0.29% of their portfolio | 1.4m $112.4m | Added +944.8k |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. 0.15% of their portfolio | 1.3m $103.1m | Added +515.1k |
| MORGAN STANLEY 0.01% of their portfolio | 1.3m $101.6m | Added +254.9k |
| Invesco Ltd. 0.01% of their portfolio | 1.1m $88.9m | Reduced -156.7k |
| VANGUARD FIDUCIARY TRUST CO 0.02% of their portfolio | 1.1m $84.1m | Added +36.5k |
| Bellevue Group AG 1.62% of their portfolio | 972.3k $77.1m | Reduced -846.4k |
| GROUPAMA ASSET MANAGMENT 0.95% of their portfolio | 937.1k $75.2m | Added +112.5k |
| NORTHERN TRUST CORP 0.01% of their portfolio | 913.6k $72.4m | Added +45.4k |
| Capital International Investors 0.01% of their portfolio | 823.8k $65.3m | New |
| Davern Capital Partners, LP 10.80% of their portfolio | 798.7k $63.3m | Added +411.8k |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 791.0k $62.7m | Reduced -49.6k |
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC 1.62% of their portfolio | 787.3k $62.4m | Reduced -616.8k |
| GW&K Investment Management, LLC 0.46% of their portfolio | 747.0k $59.2m | Reduced -32.4k |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. 0.06% of their portfolio | 734.2k $58.2m | Reduced -173.3k |
| Nuveen, LLC 0.01% of their portfolio | 726.3k $57.6m | Added +77.8k |
| Connor, Clark & Lunn Investment Management Ltd. 0.10% of their portfolio | 684.2k $54.3m | Reduced -189.9k |
| Eversept Partners, LP 2.87% of their portfolio | 664.7k $52.7m | Added +32.6k |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.22% of their portfolio | 655.5k $52.0m | Reduced -17.4k |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ 0.02% of their portfolio | 651.8k $51.7m | Reduced -14.3k |
| NEUBERGER BERMAN GROUP LLC 0.03% of their portfolio | 633.5k $50.2m | Added +190.3k |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP 0.02% of their portfolio | 632.0k $50.1m | Reduced -105.8k |
| UBS Group AG 0.01% of their portfolio | 624.9k $49.5m | Reduced -183.6k |
| TimesSquare Capital Management, LLC 0.72% of their portfolio | 614.1k $48.7m | Added +338.4k |
| EVENTIDE ASSET MANAGEMENT, LLC 0.61% of their portfolio | 575.0k $45.6m | Unchanged |
| PERCEPTIVE ADVISORS LLC 0.70% of their portfolio | 566.0k $44.9m | Added +62.0k |
| RENAISSANCE TECHNOLOGIES LLC 0.06% of their portfolio | 559.4k $44.4m | Added +253.9k |
| Bank of New York Mellon Corp 0.01% of their portfolio | 542.5k $43.0m | Added +27.8k |
| TEACHER RETIREMENT SYSTEM OF TEXAS 0.11% of their portfolio | 522.3k $41.4m | Reduced -1.6k |
| BOONE CAPITAL MANAGEMENT LLC 9.64% of their portfolio | 520.0k $41.2m | Added +19.5k |
| JANE STREET GROUP, LLC 0.03% of their portfolio | 503.6k $39.9m | Added +311.8k |
| NEW YORK STATE COMMON RETIREMENT FUND 0.05% of their portfolio | 500.1k $39.6m | Added +149.6k |
| BNP PARIBAS FINANCIAL MARKETS 0.02% of their portfolio | 454.6k $36.0m | Reduced -24.8k |
| Candriam S.C.A. 0.16% of their portfolio | 445.0k $35.3m | Reduced -39.0k |
| FIRST TRUST ADVISORS LP 0.02% of their portfolio | 427.2k $33.9m | Reduced -41.2k |
| PINNACLE ASSOCIATES LTD 0.36% of their portfolio | 419.8k $33.3m | Reduced -16.7k |
| NOMURA HOLDINGS INC 0.13% of their portfolio | 402.2k $31.9m | Added +288.1k |
| Handelsbanken Fonder AB 0.09% of their portfolio | 383.2k $30.4m | Added +169.3k |
| C WorldWide Group Holding A/S 0.70% of their portfolio | 366.0k $29.0m | Unchanged |
| TD Asset Management Inc 0.02% of their portfolio | 340.5k $27.0m | Reduced -189.4k |
| ALLIANCEBERNSTEIN L.P. 0.01% of their portfolio | 340.4k $25.6m | Reduced -60.2k |
| Freestone Grove Partners LP 0.18% of their portfolio | 340.0k $27.0m | New |
| Qube Research & Technologies Ltd 0.03% of their portfolio | 334.0k $26.5m | Added +291.1k |
| Capital Research Global Investors 0.00% of their portfolio | 331.9k $26.3m | Added +8.9k |
| CAPITAL FUND MANAGEMENT S.A. 0.19% of their portfolio | 329.6k $26.1m | Added +187.4k |
| Carmignac Gestion 0.33% of their portfolio | 321.0k $25.5m | Added +268.0k |
| Privium Fund Management B.V. 4.66% of their portfolio | 319.9k $25.4m | Added +29.9k |
| Swiss National Bank 0.01% of their portfolio | 315.0k $25.0m | Added +10.5k |
| Jump Financial, LLC 0.22% of their portfolio | 306.3k $24.3m | Added +99.7k |
| ARK Investment Management LLC 0.15% of their portfolio | 300.8k $23.8m | Added +12.1k |
| Legal & General Group Plc 0.00% of their portfolio | 299.2k $23.7m | Added +4.5k |
| D. E. Shaw & Co., Inc. 0.01% of their portfolio | 297.0k $23.6m | Reduced -132.6k |
| MILLENNIUM MANAGEMENT LLC 0.02% of their portfolio | 288.9k $22.9m | Reduced -762.6k |
| DAVENPORT & Co LLC 0.11% of their portfolio | 284.0k $22.5m | Added +45.7k |
| Aberdeen Group plc 0.03% of their portfolio | 277.4k $22.0m | Added +163.6k |
| California Public Employees Retirement System 0.01% of their portfolio | 270.8k $21.5m | Added +15.4k |
| TOCQUEVILLE ASSET MANAGEMENT L.P. 0.26% of their portfolio | 251.2k $19.9m | Added +32.0k |
| RAYMOND JAMES FINANCIAL INC 0.01% of their portfolio | 237.3k $18.8m | Added +2.2k |
| CITADEL ADVISORS LLC 0.01% of their portfolio | 236.3k $18.7m | Reduced -706.2k |
| Universal- Beteiligungs- und Servicegesellschaft mbH 0.03% of their portfolio | 233.5k $18.5m | Added +13.8k |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 226.2k $17.9m | Added +36.4k |
| Empowered Funds, LLC 0.09% of their portfolio | 223.1k $17.7m | Added +120.0k |
| Orion Investment Co 5.10% of their portfolio | 220.3k $17.5m | Reduced -4.7k |
| Life Cycle Investment Partners Ltd 0.08% of their portfolio | 219.9k $17.4m | New |
| ALGERT GLOBAL LLC 0.19% of their portfolio | 206.9k $16.4m | Added +90.3k |
| STIFEL FINANCIAL CORP 0.01% of their portfolio | 203.0k $16.1m | Added +6.3k |
| Corient Private Wealth LP 0.02% of their portfolio | 196.7k $15.6m | Added +62 |
| Eagle Health Investments LP 2.56% of their portfolio | 194.6k $15.4m | New |
| SECTOR GAMMA AS 3.26% of their portfolio | 189.5k $15.0m | Added +20.0k |
| HSBC HOLDINGS PLC 0.01% of their portfolio | 188.4k $15.0m | Added +2.4k |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.01% of their portfolio | 180.9k $14.3m | Added +4.5k |
| Polymer Capital Management (HK) LTD 1.43% of their portfolio | 177.9k $14.1m | Added +116.7k |
| DEUTSCHE BANK AG\ 0.00% of their portfolio | 169.6k $13.4m | Added +9.7k |
| ADAR1 Capital Management, LLC 0.62% of their portfolio | 166.3k $13.2m | Added +5.9k |
| RHUMBLINE ADVISERS 0.01% of their portfolio | 164.9k $13.1m | Reduced -8.5k |