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 ($13.5m this quarter). Holder counts are more reliable. Shares outstanding: 162.0m as of 2025-10-23, 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 ≈ $65.48. Options: 29 managers hold calls ($171.8m notional), 17 hold puts ($74.8m).
Trends to Q3 2025
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 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q4 2023 | 175 | 143 |
| Q1 2024 | 169 | 179 |
| Q2 2024 | 168 | 182 |
| Q3 2024 | 176 | 159 |
| Q4 2024 | 160 | 169 |
| Q1 2025 | 150 | 184 |
| Q2 2025 | 197 | 169 |
| Q3 2025 | 245 | 152 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q4 2024 | $26.1m | $30.9m | 1.18 |
| Q1 2025 | $24.8m | $18.8m | 0.76 |
| Q2 2025 | $65.2m | $34.9m | 0.54 |
| Q3 2025 | $171.8m | $74.8m | 0.44 |
Biggest buyers
| Lombard Odier Asset Management (Europe) Ltd | New | +6.5m |
| DEERFIELD MANAGEMENT COMPANY, L.P. | New | +2.0m |
| MARSHALL WACE, LLP | Added | +945.7k |
| CITADEL ADVISORS LLC | Added | +907.1k |
| AMERICAN CENTURY COMPANIES INC | Added | +899.5k |
| Pictet Asset Management Holding SA | Added | +784.5k |
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC | New | +750.0k |
| NOMURA HOLDINGS INC | Added | +701.2k |
| JPMORGAN CHASE & CO | Added | +694.0k |
| D. E. Shaw & Co., Inc. | New | +630.9k |
Biggest sellers
| T. Rowe Price Investment Management, Inc. | Reduced | -2.9m |
| ADAGE CAPITAL PARTNERS GP, L.L.C. | Reduced | -2.5m |
| BVF INC/IL | Sold out | -1.9m |
| MILLENNIUM MANAGEMENT LLC | Reduced | -1.9m |
| Bellevue Group AG | Reduced | -1.6m |
| Deep Track Capital, LP | Reduced | -1.1m |
| Woodline Partners LP | Sold out | -732.8k |
| TWO SIGMA ADVISERS, LP | Reduced | -594.5k |
| AXA S.A. | Sold out | -566.9k |
| UBS Group AG | Reduced | -482.3k |
Biggest calls
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC | New | $39.2m599.1k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $32.7m500.0k shares |
| Balyasny Asset Management L.P. | Added | $17.0m260.4k shares |
| GOLDMAN SACHS GROUP INC | New | $10.9m166.3k shares |
| BARCLAYS PLC | Added | $10.1m154.6k shares |
| CITADEL ADVISORS LLC | Added | $7.2m109.8k shares |
| DIADEMA PARTNERS LP | New | $6.5m100.0k shares |
| ROYAL BANK OF CANADA | New | $6.0m91.2k shares |
| SIMPLEX TRADING, LLC | Reduced | $4.8m73.7k shares |
| DLD Asset Management, LP | New | $4.7m71.5k shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $13.5m206.7k shares |
| GOLDMAN SACHS GROUP INC | New | $10.5m161.2k shares |
| BARCLAYS PLC | Added | $9.6m146.9k shares |
| ROYAL BANK OF CANADA | Reduced | $9.1m138.4k shares |
| CITADEL ADVISORS LLC | Added | $5.0m76.1k shares |
| SIMPLEX TRADING, LLC | Added | $4.9m75.5k shares |
| JANE STREET GROUP, LLC | Added | $4.5m68.5k shares |
| Squarepoint Ops LLC | New | $3.7m56.1k shares |
| BANK OF AMERICA CORP /DE/ | New | $2.9m45.0k shares |
| Caption Management, LLC | Reduced | $2.9m45.0k 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 in Q3 2025
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 2023 | 0 | — | 8 | $15.0m | $14.9m |
| Q1 2024 | 0 | — | 10 | $7.1m | $897.3k |
| Q2 2024 | 0 | — | 4 | $1.1m | $900.9k |
| Q3 2024 | 0 | — | 3 | $829.8k | $829.8k |
| 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 |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2025-09-30 | Geary Richard S EVP, Chief Development Officer | Sold plan | $3.8m57.9k shares |
| 2025-09-30 | HOUGEN ELIZABETH L EVP, Finance & CFO | Sold plan | $3.2m49.8k shares |
| 2025-09-30 | O'NEIL PATRICK R. EVP CLO & General Counsel | Sold plan | $959.0k14.8k shares |
| 2025-09-29 | O'NEIL PATRICK R. EVP CLO & General Counsel | Sold plan | $675.9k10.5k shares |
| 2025-09-12 | O'NEIL PATRICK R. EVP CLO & General Counsel | Sold plan | $109.8k1.7k shares |
| 2025-09-09 | O'NEIL PATRICK R. EVP CLO & General Counsel | Sold plan | $1.4m21.0k shares |
| 2025-09-09 | Baroldi Joseph EVP, Chief Business Officer | Sold plan | $742.8k11.9k shares |
| 2025-09-05 | BENNETT C FRANK EVP, Chief Scientific Officer | Sold plan | $357.6k6.0k shares |
| 2025-09-05 | Baroldi Joseph EVP, Chief Business Officer | Sold plan | $15.5k250 shares |
| 2025-09-03 | Monia Brett P Chief Executive Officer, director | Sold | $12.3m203.8k shares |
| 2025-09-03 | O'NEIL PATRICK R. EVP CLO & General Counsel | Sold plan | $4.7m76.8k shares |
| 2025-09-03 | BENNETT C FRANK EVP, Chief Scientific Officer | Sold plan | $2.1m33.9k shares |
| 2025-09-03 | Baroldi Joseph EVP, Chief Business Officer | Sold plan | $1.9m32.8k shares |
| 2025-09-03 | KLEIN JOSEPH III Director · by Trust | Sold plan | $1.7m28.0k shares |
| 2025-09-03 | KLEIN JOSEPH III Director · by Trust | Sold plan | $1.7m28.0k shares |
| 2025-09-03 | Schneider Eugene EVP, Chf Clinical Develop Ofcr | Sold plan | $1.2m19.7k shares |
| 2025-09-03 | LOSCALZO JOSEPH Director | Sold | $962.4k16.0k shares |
| 2025-09-03 | WENDER JOSEPH H Director · by Trust | Sold plan | $673.6k11.2k shares |
| 2025-09-03 | WENDER JOSEPH H Director · by Trust | Sold plan | $673.6k11.2k shares |
| 2025-09-03 | Devers Shannon L. EVP, Chief Human Resources Ofc | Sold plan | $192.9k3.2k shares |
| 2025-09-02 | PARSHALL B LYNNE Director | Sold plan | $1.0m20.0k shares |
| 2025-09-02 | WENDER JOSEPH H Director · by Trust | Sold plan | $938.6k16.8k shares |
| 2025-09-02 | WENDER JOSEPH H Director · by Trust | Sold plan | $938.6k16.8k shares |
| 2025-09-02 | O'NEIL PATRICK R. EVP CLO & General Counsel | Sold plan | $711.4k13.1k shares |
| 2025-09-02 | Swayze Eric EVP Research | Sold plan | $552.9k11.1k shares |
| 2025-09-02 | Geary Richard S EVP, Chief Development Officer | Sold plan | $503.7k10.0k shares |
| 2025-09-02 | BENNETT C FRANK EVP, Chief Scientific Officer | Sold plan | $245.7k5.0k shares |
| 2025-08-22 | Diaz Allene M. Director | Sold plan | $60.7k1.4k shares |
| 2025-08-18 | BENNETT C FRANK EVP, Chief Scientific Officer | Sold plan | $439.8k10.0k shares |
| 2025-08-06 | PARSHALL B LYNNE Director | Sold plan | $209.7k5.0k shares |
The latest 30 of 34 trades.
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, Q3 2025
| Manager | Shares | Change |
|---|---|---|
| FMR LLC 0.08% of their portfolio | 23.7m $1.5bn | Added +46.0k |
| VANGUARD GROUP INC 0.02% of their portfolio | 16.5m $1.1bn | Reduced -233.1k |
| T. Rowe Price Investment Management, Inc. 0.53% of their portfolio | 13.2m $860.7m | Reduced -2.9m |
| Capital World Investors 0.11% of their portfolio | 12.7m $832.3m | Added +182.5k |
| BlackRock, Inc. 0.01% of their portfolio | 10.4m $683.5m | Reduced -449.0k |
| WELLINGTON MANAGEMENT GROUP LLP 0.08% of their portfolio | 6.6m $431.0m | Added +243.0k |
| Lombard Odier Asset Management (Europe) Ltd 0.46% of their portfolio | 6.5m $9.0m | New |
| Bellevue Group AG 8.49% of their portfolio | 6.2m $408.5m | Reduced -1.6m |
| STATE STREET CORP 0.01% of their portfolio | 4.4m $287.1m | Reduced -141.7k |
| Deep Track Capital, LP 6.95% of their portfolio | 3.8m $249.1m | Reduced -1.1m |
| GEODE CAPITAL MANAGEMENT, LLC 0.01% of their portfolio | 3.1m $200.6m | Added +175.2k |
| Tweedy, Browne Co LLC 16.48% of their portfolio | 2.9m $189.8m | Added +9.3k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.02% of their portfolio | 2.7m $178.6m | Reduced -396.4k |
| CITADEL ADVISORS LLC 0.13% of their portfolio | 2.4m $157.1m | Added +907.1k |
| TWO SIGMA ADVISERS, LP 0.27% of their portfolio | 2.1m $135.6m | Reduced -594.5k |
| DEERFIELD MANAGEMENT COMPANY, L.P. 1.98% of their portfolio | 2.0m $129.5m | New |
| TWO SIGMA INVESTMENTS, LP 0.16% of their portfolio | 1.6m $103.1m | Reduced -212.4k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.02% of their portfolio | 1.5m $99.4m | Added +32.1k |
| Pictet Asset Management Holding SA 0.09% of their portfolio | 1.4m $90.5m | Added +784.5k |
| AMERICAN CENTURY COMPANIES INC 0.05% of their portfolio | 1.4m $89.8m | Added +899.5k |
| ADAGE CAPITAL PARTNERS GP, L.L.C. 0.14% of their portfolio | 1.3m $86.0m | Reduced -2.5m |
| ROYAL BANK OF CANADA 0.01% of their portfolio | 1.2m $80.2m | Reduced -373.2k |
| MORGAN STANLEY 0.00% of their portfolio | 1.2m $77.2m | Reduced -181.9k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.02% of their portfolio | 1.2m $75.5m | Added +363.1k |
| MACQUARIE GROUP LTD 0.09% of their portfolio | 1.1m $74.1m | Reduced -302.1k |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 1.1m $71.2m | Added +694.0k |
| Vestal Point Capital, LP 3.19% of their portfolio | 1.1m $70.3m | Added +575.0k |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. 0.18% of their portfolio | 1.1m $69.3m | Reduced -291.2k |
| UBS Group AG 0.01% of their portfolio | 1.0m $68.5m | Reduced -482.3k |
| Polar Capital Holdings Plc 0.33% of their portfolio | 1.0m $67.6m | Added +33.6k |
| TD Asset Management Inc 0.05% of their portfolio | 960.3k $62.8m | Reduced -144.4k |
| MARSHALL WACE, LLP 0.07% of their portfolio | 958.8k $62.7m | Added +945.7k |
| Artisan Partners Limited Partnership 0.08% of their portfolio | 890.1k $58.2m | Added +535.1k |
| Connor, Clark & Lunn Investment Management Ltd. 0.18% of their portfolio | 878.2k $57.4m | Added +612.4k |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ 0.02% of their portfolio | 862.6k $56.4m | Added +343.4k |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 855.3k $56.0m | Reduced -140.6k |
| NORTHERN TRUST CORP 0.01% of their portfolio | 844.9k $55.3m | Added +30.7k |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.18% of their portfolio | 803.0k $52.5m | Reduced -51.6k |
| MILLENNIUM MANAGEMENT LLC 0.04% of their portfolio | 779.6k $51.0m | Reduced -1.9m |
| GOLDMAN SACHS GROUP INC 0.01% of their portfolio | 777.6k $50.9m | Reduced -370 |
| AMERIPRISE FINANCIAL INC 0.01% of their portfolio | 765.8k $50.1m | Added +397.7k |
| Balyasny Asset Management L.P. 0.10% of their portfolio | 760.1k $49.7m | Reduced -8.5k |
| SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC 1.60% of their portfolio | 750.0k $49.1m | New |
| BANK OF MONTREAL /CAN/ 0.02% of their portfolio | 747.4k $48.9m | Added +264.1k |
| NOMURA HOLDINGS INC 0.22% of their portfolio | 733.4k $48.0m | Added +701.2k |
| BARCLAYS PLC 0.02% of their portfolio | 714.0k $46.7m | Added +130.8k |
| ARK Investment Management LLC 0.25% of their portfolio | 631.2k $41.3m | Reduced -269.1k |
| D. E. Shaw & Co., Inc. 0.03% of their portfolio | 630.9k $41.3m | New |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP 0.03% of their portfolio | 630.1k $41.2m | New |
| Candriam S.C.A. 0.21% of their portfolio | 611.2k $40.0m | Reduced -113.5k |
| BAKER BROS. ADVISORS LP 0.27% of their portfolio | 566.8k $37.1m | New |
| GROUPAMA ASSET MANAGMENT 0.54% of their portfolio | 561.8k $36.8m | Reduced -99.2k |
| TANG CAPITAL MANAGEMENT LLC 1.39% of their portfolio | 550.0k $36.0m | Added +400.0k |
| Eversept Partners, LP 2.70% of their portfolio | 538.7k $35.2m | Reduced -50.2k |
| Bank of New York Mellon Corp 0.01% of their portfolio | 532.1k $34.8m | Added +4.9k |
| Invesco Ltd. 0.01% of their portfolio | 519.1k $34.0m | Added +262.8k |
| Hudson Bay Capital Management LP 0.20% of their portfolio | 515.0k $33.7m | Reduced -235.0k |
| GROUPAMA ASSET MANAGMENT 0.01% of their portfolio | 500.0k $685.3k | Unchanged |
| RENAISSANCE TECHNOLOGIES LLC 0.04% of their portfolio | 486.7k $31.8m | Added +216.0k |
| PINNACLE ASSOCIATES LTD 0.42% of their portfolio | 481.8k $31.5m | Reduced -12.8k |
| TEACHER RETIREMENT SYSTEM OF TEXAS 0.12% of their portfolio | 473.9k $31.0m | Reduced -194.3k |
| C WorldWide Group Holding A/S 0.43% of their portfolio | 426.0k $27.9m | Reduced -24.0k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.04% of their portfolio | 420.9k $27.5m | New |
| BOONE CAPITAL MANAGEMENT LLC 8.96% of their portfolio | 417.8k $27.3m | New |
| Nuveen, LLC 0.01% of their portfolio | 415.6k $27.2m | Added +170.5k |
| Ikarian Capital, LLC 5.49% of their portfolio | 415.2k $27.2m | New |
| AXA Investment Managers S.A. 0.07% of their portfolio | 406.5k $26.6m | First filing |
| Squarepoint Ops LLC 0.05% of their portfolio | 383.8k $25.1m | Added +249.4k |
| BNP PARIBAS FINANCIAL MARKETS 0.02% of their portfolio | 383.2k $25.1m | Added +205.5k |
| JANE STREET GROUP, LLC 0.03% of their portfolio | 365.1k $23.9m | New |
| Man Group plc 0.04% of their portfolio | 333.8k $21.8m | Added +324.9k |
| Legal & General Group Plc 0.00% of their portfolio | 319.6k $20.9m | Reduced -84.8k |
| Assenagon Asset Management S.A. 0.03% of their portfolio | 312.3k $20.4m | Added +294.6k |
| Alyeska Investment Group, L.P. 0.06% of their portfolio | 311.3k $20.4m | Added +152.2k |
| Rhenman & Partners Asset Management AB 2.24% of their portfolio | 310.0k $20.3m | Added +128.0k |
| Swiss National Bank 0.01% of their portfolio | 293.1k $19.2m | Added +4.5k |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 285.3k $18.7m | Added +75.4k |
| SECTOR GAMMA AS 4.40% of their portfolio | 271.0k $17.7m | Reduced -14.9k |
| GW&K Investment Management, LLC 0.15% of their portfolio | 264.0k $17.3m | Reduced -184.8k |
| ALGERT GLOBAL LLC 0.28% of their portfolio | 252.3k $16.5m | Added +214.2k |
| Privium Fund Management B.V. 2.93% of their portfolio | 248.9k $16.3m | Reduced -18.7k |
| RAYMOND JAMES FINANCIAL INC 0.01% of their portfolio | 240.4k $15.7m | Added +29.8k |
| Jain Global LLC 0.19% of their portfolio | 225.7k $14.8m | Added +218.5k |
| Orion Investment Co 4.67% of their portfolio | 224.7k $14.7m | Added +7.3k |
| California Public Employees Retirement System 0.01% of their portfolio | 215.8k $14.1m | Added +13.9k |
| Trexquant Investment LP 0.15% of their portfolio | 215.1k $14.1m | Added +86.3k |
| STIFEL FINANCIAL CORP 0.01% of their portfolio | 202.6k $13.3m | Added +6.3k |
| Schonfeld Strategic Advisors LLC 0.09% of their portfolio | 200.8k $13.1m | Reduced -248.4k |
| Universal- Beteiligungs- und Servicegesellschaft mbH 0.02% of their portfolio | 197.4k $12.9m | Added +47.6k |
| TOCQUEVILLE ASSET MANAGEMENT L.P. 0.18% of their portfolio | 193.0k $12.6m | Added +5.7k |
| GREAT LAKES ADVISORS, LLC 0.10% of their portfolio | 186.9k $12.2m | Reduced -212.7k |
| RHUMBLINE ADVISERS 0.01% of their portfolio | 182.1k $11.9m | Added +462 |
| Cinctive Capital Management LP 0.57% of their portfolio | 173.8k $11.4m | New |
| Sonora Investment Management Group, LLC 0.79% of their portfolio | 169.8k $11.1m | Added +6.6k |
| NEW YORK STATE COMMON RETIREMENT FUND 0.01% of their portfolio | 168.2k $11.0m | Added +81.2k |
| Sicart Associates LLC 2.91% of their portfolio | 164.3k $10.7m | Reduced -21.0k |
| BOOTHBAY FUND MANAGEMENT, LLC 0.27% of their portfolio | 163.5k $10.7m | New |
| Capricorn Fund Managers Ltd 3.58% of their portfolio | 162.8k $10.7m | New |
| Aquatic Capital Management LLC 0.19% of their portfolio | 159.0k $10.4m | First filing |
| EDMOND DE ROTHSCHILD HOLDING S.A. 0.16% of their portfolio | 156.7k $10.3m | Reduced -40.9k |