Annexon, Inc. (ANNX) Ownership
ANNX ownership summary
as of October 18, 2026- Institutions
- 103.4% of shares outstanding
- Insiders
- 0.44% of shares outstanding
- Shares outstanding
- 189.6M
- Float
- 163.8M shares available to trade
- Short interest
- 17.87% 32.0M shares short
- Days to cover
- 9.94 short interest down 2.6% vs prior month
- Institutions 103.41%
- Insiders 0.44%
ANNX top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | FMR Inc | 10.30% | 19.5M | $66.6M | +8.9M (+83.5%) | June 30, 2026 |
| 2 | BlackRock Inc | 7.14% | 13.5M | $46.2M | +2.6M (+23.8%) | June 30, 2026 |
| 3 | Redmile Group, LLC | 6.26% | 11.9M | $40.5M | −2.7M (−18.4%) | June 30, 2026 |
| 4 | State Street Corp | 5.18% | 9.8M | $33.5M | +2.9M (+42.0%) | June 30, 2026 |
| 5 | Bvf Inc | 4.59% | 8.7M | $29.7M | — | June 30, 2026 |
| 6 | Woodline Partners LP | 3.65% | 6.9M | $23.6M | +4.6M (+196.3%) | June 30, 2026 |
| 7 | Vanguard Capital Management, LLC | 3.62% | 6.9M | $23.4M | +914,426 (+15.4%) | June 30, 2026 |
| 8 | Mak Capital One LLC | 3.09% | 5.9M | $20.0M | +1.1M (+24.1%) | June 30, 2026 |
| 9 | The Goldman Sachs Group Inc | 3.07% | 5.8M | $19.9M | +3.7M (+170.6%) | June 30, 2026 |
| 10 | Siren, L.L.C. | 2.35% | 4.5M | $15.2M | +500,000 (+12.6%) | June 30, 2026 |
| 11 | Bain Capital Life Sciences Investors, LLC | 2.34% | 4.4M | $15.1M | −774,943 (−14.9%) | June 30, 2026 |
| 12 | Bellevue Group AG | 2.16% | 4.1M | $14.0M | −1.1M (−20.5%) | June 30, 2026 |
| 13 | Geode Capital Management, LLC | 2.13% | 4.0M | $13.8M | +659,370 (+19.5%) | June 30, 2026 |
| 14 | MPM Oncology Impact Management LP | 1.87% | 3.5M | $12.1M | +3.5M (0.0%) | June 30, 2026 |
| 15 | Ameriprise Financial Inc | 1.85% | 3.5M | $12.0M | +60,502 (+1.8%) | June 30, 2026 |
| 16 | Great Point Partners LLC | 1.85% | 3.5M | $11.9M | +1.0M (+40.0%) | June 30, 2026 |
| 17 | Adage Capital Partners Gp LLC | 1.85% | 3.5M | $11.9M | −800,000 (−18.6%) | June 30, 2026 |
| 18 | Morgan Stanley - Brokerage Accounts | 1.66% | 3.1M | $10.7M | +408,483 (+14.9%) | June 30, 2026 |
| 19 | Palo Alto Investors, LLC | 1.56% | 2.9M | $10.1M | — | June 30, 2026 |
| 20 | Balyasny Asset Management LLC | 1.49% | 2.8M | $9.7M | −1.1M (−27.2%) | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 13 holders added 30.9M shares and 5 cut 6.4M.
ANNX top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | Fidelity Select Biotechnology | 3.26% | 6.2M | $21.1M | — | August 31, 2026 |
| 2 | State Street® SPDR® S&P® Biotech ETF | 3.10% | 5.9M | $20.1M | −112,500 (−1.9%) | September 30, 2026 |
| 3 | Vanguard MStar Total Stk Mkt Idx Invest | 2.62% | 5.0M | $16.9M | — | August 31, 2026 |
| 4 | iShares Russell 2000 ETF | 2.15% | 4.1M | $13.9M | −47,040 (−1.1%) | September 30, 2026 |
| 5 | Fidelity Stock Selector Small Cap | 1.09% | 2.1M | $7.1M | +446,900 (+27.6%) | July 31, 2026 |
| 6 | Columbia Acorn Inst | 0.96% | 1.8M | $6.2M | — | August 31, 2026 |
| 7 | Fidelity Small Cap Growth | 0.94% | 1.8M | $6.1M | +547,394 (+44.1%) | July 31, 2026 |
| 8 | Fidelity Small Cap Index | 0.89% | 1.7M | $5.8M | +11,859 (+0.7%) | July 31, 2026 |
| 9 | Fidelity Advisor Biotechnology I | 0.88% | 1.7M | $5.7M | — | August 31, 2026 |
| 10 | iShares Russell 2000 Growth ETF | 0.78% | 1.5M | $5.0M | −1,865 (−0.1%) | September 30, 2026 |
| 11 | Columbia Small Cap Value Discv A | 0.74% | 1.4M | $4.8M | +8,800 (+0.6%) | August 31, 2026 |
| 12 | Strategic Advisers Fidelity US TtlStk | 0.69% | 1.3M | $4.5M | +203,676 (+18.5%) | August 31, 2026 |
| 13 | iShares Biotechnology ETF | 0.68% | 1.3M | $4.4M | −9,720 (−0.8%) | September 30, 2026 |
| 14 | Columbia Small Cap Growth Inst | 0.64% | 1.2M | $4.2M | — | August 31, 2026 |
| 15 | Fidelity Select Health Care | 0.63% | 1.2M | $4.1M | — | August 31, 2026 |
| 16 | Fidelity Series Small Cap Opps | 0.63% | 1.2M | $4.0M | +78,500 (+7.1%) | July 31, 2026 |
| 17 | Fidelity Enhanced Small Cap Core ETF | 0.57% | 1.1M | $3.7M | +2,256 (+0.2%) | September 30, 2026 |
| 18 | CREF Total Global Stock Account R3 | 0.54% | 1.0M | $3.5M | +181,220 (+21.6%) | July 31, 2026 |
| 19 | Fidelity Select Pharmaceuticals Port | 0.53% | 1.0M | $3.4M | — | August 31, 2026 |
| 20 | Foord International B | 0.53% | 1.0M | $3.4M | +1.0M (0.0%) | June 30, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
ANNX insider transactions
latest 20| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-04-10 | William H Carson | Buy | $6.20 | 8,000 | $49,600 |
| 2026-03-10 | William H Carson | Buy | $5.67 | 8,000 | $45,360 |
| 2026-02-18 | Dean Richard Artis | Sell | $5.10 | 5,290 | $26,979 |
| 2026-02-18 | Jamie Dananberg | Sell | $5.10 | 5,290 | $26,979 |
| 2026-02-18 | Jennifer Lew | Sell | $5.11 | 7,851 | $40,119 |
| 2026-02-18 | Michael Overdorf | Sell | $5.10 | 6,225 | $31,747 |
| 2026-02-18 | Ted Yednock | Sell | $5.11 | 7,857 | $40,149 |
| 2025-12-30 | William H Carson | Buy | $5.02 | 4,115 | $20,657 |
| 2025-12-01 | Jung Choi | Buy | $4.19 | 33,000 | $138,270 |
| 2025-12-01 | William H Carson | Buy | $4.47 | 4,115 | $18,394 |
| 2025-11-21 | Muneer A Satter | Buy | $4.28 | 422,613 | $1.8M |
| 2025-11-20 | Muneer A Satter | Buy | $4.48 | 400,000 | $1.8M |
| 2025-11-19 | Muneer A Satter | Buy | $3.94 | 500,000 | $2.0M |
| 2025-11-17 | Muneer A Satter | Buy | $2.99 | 500,000 | $1.5M |
| 2025-10-30 | William H Carson | Buy | $3.17 | 4,115 | $13,045 |
| 2025-09-30 | William H Carson | Buy | $3.05 | 4,115 | $12,551 |
| 2025-07-30 | William H Carson | Buy | $2.43 | 4,115 | $9,999 |
| 2025-07-14 | Jennifer Lew | Sell | $2.58 | 1,117 | $2,882 |
| 2025-07-14 | Jennifer Lew | Sell | $2.58 | 1,117 | $2,882 |
| 2025-07-14 | Michael Overdorf | Sell | $2.61 | 853 | $2,226 |
Reported trades by company officers, directors and other filers (including disclosures by members of Congress where EODHD lists them). "—" where the filing gives no share count.
ANNX shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns ANNX
Institutional investors own 103.4% of Annexon's shares and insiders 0.44%. The largest holder is FMR Inc with 10.30% of the shares (19.5M), as of June 30, 2026. Among the top 20 institutions, 13 added shares and 5 reduced their stake in the latest filings. Short interest is 17.87% of the float, or 9.94 days of average trading volume. The share count rose 35,754.3% since 2018.
Related: ANNX analyst forecast, ANNX key metrics. See the ANNX stock overview for the latest quote and news.
ANNX ownership FAQ
Who owns the most Annexon stock?
The largest shareholders of Annexon are FMR Inc (10.30%), BlackRock Inc (7.14%), Redmile Group, LLC (6.26%), State Street Corp (5.18%), Bvf Inc (4.59%).
What percentage of Annexon is owned by institutions?
Institutions hold 103.4% of Annexon's shares outstanding; insiders hold 0.44%.
Which funds own Annexon?
The largest fund holders of Annexon are Fidelity Select Biotechnology (3.26%), State Street® SPDR® S&P® Biotech ETF (3.10%), Vanguard MStar Total Stk Mkt Idx Invest (2.62%), iShares Russell 2000 ETF (2.15%), Fidelity Stock Selector Small Cap (1.09%).
What is Annexon's short interest?
32.0M shares of Annexon were sold short, 17.87% of the float; at the average daily volume it would take 9.94 days to cover.
Are insiders buying or selling Annexon?
Of the latest 20 reported insider transactions in Annexon (since July 14, 2025), 12 were purchases and 8 were sales.
How many shares of Annexon are outstanding?
Annexon has 189.6M shares outstanding, of which 163.8M are in the public float.