ANNEXON INC ANNX
COM · Common Stock · CUSIP 03589W102
- SectorHealth care
- IndustryPharmaceutical Preparations
- HeadquartersBrisbane, CA
- 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 ($922.1k this quarter). Holder counts are more reliable. Implied quarter-end price ≈ $5.12. Options: 5 managers hold calls ($1.0m notional), 5 hold puts ($1.1m).
Trends to Q4 2024
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 73 |
| Q4 2022 | 86 |
| Q1 2023 | 102 |
| Q2 2023 | 97 |
| Q3 2023 | 95 |
| Q4 2023 | 101 |
| Q1 2024 | 129 |
| Q2 2024 | 141 |
| Q3 2024 | 143 |
| Q4 2024 | 154 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q1 2023 | 64 | 31 |
| Q2 2023 | 65 | 50 |
| Q3 2023 | 43 | 43 |
| Q4 2023 | 54 | 39 |
| Q1 2024 | 80 | 38 |
| Q2 2024 | 90 | 61 |
| Q3 2024 | 77 | 56 |
| Q4 2024 | 84 | 56 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q1 2024 | $16.1m | $4.3m | 0.27 |
| Q2 2024 | $26.3m | $11.6m | 0.44 |
| Q3 2024 | $1.4m | $1.5m | 1.12 |
| Q4 2024 | $1.0m | $1.1m | 1.03 |
Biggest buyers
| FMR LLC | Added | +5.7m |
| SPHERA FUNDS MANAGEMENT LTD. | New | +1.2m |
| EVENTIDE ASSET MANAGEMENT, LLC | New | +1.0m |
| Sio Capital Management, LLC | Added | +933.9k |
| BlackRock, Inc. | Added | +838.5k |
| AMERIPRISE FINANCIAL INC | Added | +767.9k |
| STATE STREET CORP | Added | +668.8k |
| Tetragon Partners GP Ltd | Added | +615.6k |
| VANGUARD GROUP INC | Added | +576.6k |
| MUTUAL OF AMERICA CAPITAL MANAGEMENT LLC | Added | +370.4k |
Biggest sellers
| Bain Capital Life Sciences Investors, LLC | Reduced | -3.2m |
| ADAGE CAPITAL PARTNERS GP, L.L.C. | Sold out | -2.8m |
| GMT Capital Corp | Sold out | -1.9m |
| JPMORGAN CHASE & CO | Reduced | -1.9m |
| ACADIAN ASSET MANAGEMENT LLC | Reduced | -789.4k |
| Woodline Partners LP | Reduced | -739.4k |
| MORGAN STANLEY | Reduced | -590.8k |
| Schonfeld Strategic Advisors LLC | Reduced | -589.1k |
| GOLDMAN SACHS GROUP INC | Reduced | -587.4k |
| Alyeska Investment Group, L.P. | Sold out | -450.0k |
Biggest calls
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $667.9k130.2k shares |
| GROUP ONE TRADING LLC | Added | $182.1k35.5k shares |
| SIMPLEX TRADING, LLC | Reduced | $115.0k22.5k shares |
| CITADEL ADVISORS LLC | Reduced | $79.0k15.4k shares |
| CONCOURSE FINANCIAL GROUP SECURITIES, INC. | Unchanged | $00 shares |
Biggest puts
| CITADEL ADVISORS LLC | Added | $454.0k88.5k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $436.1k85.0k shares |
| GROUP ONE TRADING LLC | Reduced | $106.2k20.7k shares |
| SIMPLEX TRADING, LLC | Reduced | $80.0k15.7k shares |
| CONCOURSE FINANCIAL GROUP SECURITIES, INC. | Unchanged | $00 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 |
|---|---|
| FMR LLC 13G · institution +4.8 pts · filed 2026-07-08 | 11.9% |
| Redmile Group, LLC 13G · passive investor no change · filed 2026-07-08 | 9.9% |
| BlackRock, Inc. 13G · institution +1.9 pts · filed 2026-07-27 | 8.0% |
| Satter Muneer A 13D · may seek influence filed 2025-11-21 | 7.2% |
| STATE STREET CORP 13G · institution new · filed 2026-08-07 | 6.0% |
| BIOTECHNOLOGY VALUE FUND L P 13G · passive investor filed 2026-05-15 | 5.4% |
Fell to 5% or below in the last year: VANGUARD GROUP INC (0.0%, 2026-03-26)
Insider purchases and sales in Q4 2024
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 |
|---|---|---|---|---|---|
| Q1 2023 | 1 | $18.0m | 3 | $61.0k | — |
| Q2 2023 | 0 | — | 0 | — | — |
| Q3 2023 | 0 | — | 3 | $7.8k | — |
| Q4 2023 | 1 | $1.0m | 1 | $94.9k | $94.9k |
| Q1 2024 | 0 | — | 4 | $98.9k | — |
| Q2 2024 | 1 | $49.9k | 0 | — | — |
| Q3 2024 | 1 | $53.5k | 3 | $147.6k | $129.6k |
| Q4 2024 | 1 | $36.2k | 1 | $40.1k | $40.1k |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2024-12-02 | Carson William H. Director | Bought plan | $17.1k3.2k shares |
| 2024-10-15 | Yednock Ted EVP & CHIEF INNOVATION OFFICER | Sold plan | $40.1k5.4k shares |
| 2024-10-01 | Carson William H. Director | Bought plan | $19.1k3.2k 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, Q4 2024
| Manager | Shares | Change |
|---|---|---|
| FMR LLC 0.00% of their portfolio | 14.2m $73.0m | Added +5.7m |
| BlackRock, Inc. 0.00% of their portfolio | 8.5m $43.5m | Added +838.5k |
| Alerce Investment Management, L.P. 66.89% of their portfolio | 7.4m $38.0m | Unchanged |
| BVF INC/IL 1.22% of their portfolio | 7.0m $35.9m | Unchanged |
| Redmile Group, LLC 2.25% of their portfolio | 6.3m $32.3m | Reduced -126.8k |
| Point72 Asset Management, L.P. 0.08% of their portfolio | 5.6m $28.9m | Added +299.8k |
| VANGUARD GROUP INC 0.00% of their portfolio | 5.5m $28.5m | Added +576.6k |
| Bain Capital Life Sciences Investors, LLC 3.17% of their portfolio | 5.2m $26.9m | Reduced -3.2m |
| Bellevue Group AG 0.51% of their portfolio | 5.2m $26.5m | Unchanged |
| STATE STREET CORP 0.00% of their portfolio | 4.5m $23.1m | Added +668.8k |
| Nuveen Asset Management, LLC 0.00% of their portfolio | 2.7m $14.0m | Added +164.9k |
| Woodline Partners LP 0.09% of their portfolio | 2.7m $13.8m | Reduced -739.4k |
| Logos Global Management LP 1.53% of their portfolio | 2.5m $13.1m | Reduced -50.0k |
| Candriam S.C.A. 0.07% of their portfolio | 2.5m $13.0m | Added +341.4k |
| Sio Capital Management, LLC 3.42% of their portfolio | 2.4m $12.1m | Added +933.9k |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 2.2m $11.1m | Added +27.8k |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 1.5m $7.8m | Reduced -1.9m |
| Tetragon Partners GP Ltd 2.32% of their portfolio | 1.4m $7.2m | Added +615.6k |
| DIMENSIONAL FUND ADVISORS LP 0.00% of their portfolio | 1.4m $7.0m | Added +231.0k |
| GOLDMAN SACHS GROUP INC 0.00% of their portfolio | 1.3m $6.8m | Reduced -587.4k |
| SPHERA FUNDS MANAGEMENT LTD. 1.18% of their portfolio | 1.2m $6.4m | New |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio | 1.1m $5.7m | Added +69.7k |
| KENNEDY CAPITAL MANAGEMENT LLC 0.12% of their portfolio | 1.1m $5.6m | Reduced -359.1k |
| NORTHERN TRUST CORP 0.00% of their portfolio | 1.0m $5.3m | Added +239.7k |
| MUTUAL OF AMERICA CAPITAL MANAGEMENT LLC 0.06% of their portfolio | 1.0m $5.3m | Added +370.4k |
| EVENTIDE ASSET MANAGEMENT, LLC 0.10% of their portfolio | 1.0m $5.2m | New |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ 0.00% of their portfolio | 1.0m $5.2m | Reduced -144.3k |
| AMERIPRISE FINANCIAL INC 0.00% of their portfolio | 926.6k $4.8m | Added +767.9k |
| READYSTATE ASSET MANAGEMENT LP 0.17% of their portfolio | 774.9k $4.0m | Unchanged |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio | 743.8k $3.8m | Added +11.6k |
| Walleye Capital LLC 0.03% of their portfolio | 656.3k $3.4m | Added +327.6k |
| MORGAN STANLEY 0.00% of their portfolio | 644.7k $3.3m | Reduced -590.8k |
| DEERFIELD MANAGEMENT COMPANY, L.P. 0.06% of their portfolio | 583.9k $3.0m | Unchanged |
| Rhenman & Partners Asset Management AB 0.29% of their portfolio | 542.5k $2.8m | Reduced -17.5k |
| DEUTSCHE BANK AG\ 0.00% of their portfolio | 536.5k $2.8m | Added +28.4k |
| RENAISSANCE TECHNOLOGIES LLC 0.00% of their portfolio | 493.7k $2.5m | Added +92.3k |
| Board of Trustees of The Leland Stanford Junior University 0.21% of their portfolio | 482.6k $2.5m | Unchanged |
| Qube Research & Technologies Ltd 0.00% of their portfolio | 461.4k $2.4m | Added +31.8k |
| Hennion & Walsh Asset Management, Inc. 0.10% of their portfolio | 429.6k $2.2m | Added +170.2k |
| Parkman Healthcare Partners LLC 0.23% of their portfolio | 330.8k $1.7m | Added +2.2k |
| UBS Group AG 0.00% of their portfolio | 328.7k $1.7m | Added +109.6k |
| OCONNOR, A Distinct Business Unit of UBS ASSET MANAGEMENT AMERICAS (LLC) 0.04% of their portfolio | 318.9k $1.6m | Reduced -1.7k |
| WELLINGTON MANAGEMENT GROUP LLP 0.00% of their portfolio | 268.2k $1.4m | Added +4.8k |
| Driehaus Capital Management LLC 0.00% of their portfolio | 258.3k $547.4k | Unchanged |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 235.8k $1.2m | Added +17.5k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 230.5k $1.2m | Added +6.2k |
| Rafferty Asset Management, LLC 0.00% of their portfolio | 218.4k $1.1m | Added +41.5k |
| BARCLAYS PLC 0.00% of their portfolio | 207.0k $1.1m | Added +29.2k |
| AMERICAN CENTURY COMPANIES INC 0.00% of their portfolio | 178.5k $915.8k | Added +34.3k |
| Artia Global Partners LP 0.36% of their portfolio | 172.2k $883.5k | Unchanged |
| PRUDENTIAL FINANCIAL INC 0.00% of their portfolio | 171.7k $880.7k | Added +10.4k |
| CITIGROUP INC 0.00% of their portfolio | 168.8k $865.9k | Added +98.8k |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.00% of their portfolio | 159.0k $815.8k | Reduced -567 |
| J. Safra Sarasin Holding AG 0.01% of their portfolio | 155.7k $799.0k | New |
| MILLENNIUM MANAGEMENT LLC 0.00% of their portfolio | 155.7k $798.6k | Added +83.0k |
| ACADIAN ASSET MANAGEMENT LLC 0.00% of their portfolio | 155.6k $798.0k | Reduced -789.4k |
| Point72 Europe (London) LLP 0.05% of their portfolio | 155.6k $798.1k | Reduced -4.4k |
| Exome Asset Management LLC 0.56% of their portfolio | 144.8k $743.0k | New |
| RHUMBLINE ADVISERS 0.00% of their portfolio | 141.9k $727.7k | Added +5.9k |
| TWO SIGMA INVESTMENTS, LP 0.00% of their portfolio | 137.2k $703.7k | Reduced -3.7k |
| Cinctive Capital Management LP 0.04% of their portfolio | 135.5k $694.9k | Reduced -51.4k |
| Swiss National Bank 0.00% of their portfolio | 135.0k $692.5k | New |
| TD Asset Management Inc 0.00% of their portfolio | 133.6k $685.6k | Unchanged |
| SUSQUEHANNA FUNDAMENTAL INVESTMENTS, LLC 0.01% of their portfolio | 119.7k $614.2k | First filing |
| PARK AVENUE SECURITIES LLC 0.01% of their portfolio | 118.1k $606.0k | Unchanged |
| ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio | 111.3k $571.0k | Reduced -16.1k |
| JANE STREET GROUP, LLC 0.00% of their portfolio | 92.4k $473.9k | Added +25.5k |
| ALPS ADVISORS INC 0.00% of their portfolio | 86.2k $442.2k | Added +11.8k |
| Legal & General Group Plc 0.00% of their portfolio | 85.5k $438.8k | Added +71.7k |
| ExodusPoint Capital Management, LP 0.00% of their portfolio | 83.4k $428.0k | New |
| OSAIC HOLDINGS, INC. 0.00% of their portfolio | 80.5k $412.8k | Added +17.9k |
| STATE OF WISCONSIN INVESTMENT BOARD 0.00% of their portfolio | 69.2k $355.2k | Added +43.3k |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio | 66.4k $340.5k | Added +59.4k |
| MetLife Investment Management, LLC 0.00% of their portfolio | 65.0k $333.3k | Added +9.8k |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.00% of their portfolio | 63.4k $325.3k | Added +4.1k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.00% of their portfolio | 62.8k $322.4k | Added +31.7k |
| Quarry LP 0.06% of their portfolio | 58.0k $297.5k | Added +38.0k |
| Squarepoint Ops LLC 0.00% of their portfolio | 57.2k $293.2k | Reduced -49.4k |
| FRANKLIN RESOURCES INC 0.00% of their portfolio | 49.3k $253.0k | Reduced -82 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio | 49.1k $251.7k | New |
| Corebridge Financial, Inc. 0.00% of their portfolio | 48.5k $249.0k | Reduced -2.6k |
| DNB Asset Management AS 0.00% of their portfolio | 47.7k $244.5k | Added +861 |
| Schonfeld Strategic Advisors LLC 0.00% of their portfolio | 47.3k $242.6k | Reduced -589.1k |
| INTECH INVESTMENT MANAGEMENT LLC 0.00% of their portfolio | 45.7k $234.6k | Added +19.7k |
| PRELUDE CAPITAL MANAGEMENT, LLC 0.02% of their portfolio | 43.4k $222.5k | New |
| PROFUND ADVISORS LLC 0.01% of their portfolio | 42.3k $216.9k | Added +6.8k |
| MARSHALL WACE, LLP 0.00% of their portfolio | 38.8k $199.3k | Reduced -253.5k |
| XTX Topco Ltd 0.02% of their portfolio | 35.2k $180.3k | New |
| JANUS HENDERSON GROUP PLC 0.00% of their portfolio | 34.5k $177.2k | New |
| NEW YORK STATE COMMON RETIREMENT FUND 0.00% of their portfolio | 34.5k $176.9k | Added +20.3k |
| AQR CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 33.2k $170.1k | Reduced -31.6k |
| ProShare Advisors LLC 0.00% of their portfolio | 32.5k $167.0k | Added +14.5k |
| Invesco Ltd. 0.00% of their portfolio | 31.9k $163.6k | Added +10.6k |
| Shay Capital LLC 0.04% of their portfolio | 31.0k $159.0k | New |
| SG Americas Securities, LLC 0.00% of their portfolio | 31.0k $159.0k | Reduced -1.8k |
| HSBC HOLDINGS PLC 0.00% of their portfolio | 30.8k $156.5k | Reduced -7.0k |
| SHERBROOKE PARK ADVISERS LLC 0.05% of their portfolio | 30.1k $154.6k | Reduced -12.9k |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 29.9k $153.6k | Reduced -137.2k |
| SIMPLEX TRADING, LLC 0.00% of their portfolio | 29.4k $150.0k | Added +3.6k |
| VOYA INVESTMENT MANAGEMENT LLC 0.00% of their portfolio | 28.6k $146.7k | Reduced -1.4k |