Annexon, Inc.
Annexon, Inc. (ANNX) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · ANNX · as of Mar 31, 2025
Ownership Breakdown
152
Institutional Holders
▼ 4 vs Q4
$192.19M
Total Inst. Value
▼ $382.44M vs Q4
119.60M
Shares Outstanding
freeFloat 107.16%
99.76M
13F Shares Held
▼ 12.41M vs Q4
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
ANNX largest shareholders · institutional ownership
Q1 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
FMR LLC pharmaceutical preparations | 13.26M | 8.95% | 8.95% | $25.60B | May 12, 2025 | ▼ 962.1K |
BLACKROCK, INC. pharmaceutical preparations | 8.53M | 5.76% | 5.76% | $16.46B | May 2, 2025 | ▲ 40.3K |
BVF INC/IL pharmaceutical preparations | 7.00M | 4.73% | 4.73% | $13.51B | May 15, 2025 | — held |
REDMILE GROUP, LLC pharmaceutical preparations | 6.30M | 4.25% | 4.25% | $12.16B | May 15, 2025 | — held |
VANGUARD GROUP INC pharmaceutical preparations | 5.38M | 3.63% | 3.63% | $10.38B | May 9, 2025 | ▼ 167.3K |
BAIN CAPITAL LIFE SCIENCES INVESTORS, LLC pharmaceutical preparations | 5.25M | 3.54% | 3.54% | $10.13B | May 15, 2025 | — held |
BELLEVUE GROUP AG pharmaceutical preparations | 5.16M | 3.48% | 3.48% | $9.95B | May 14, 2025 | — held |
LOGOS GLOBAL MANAGEMENT LP pharmaceutical preparations | 4.00M | 2.70% | 2.70% | $7.72B | May 15, 2025 | ▲ 1.45M |
AMERIPRISE FINANCIAL INC pharmaceutical preparations | 3.99M | 2.69% | 2.69% | $7.69B | May 14, 2025 | ▲ 3.06M |
SIO CAPITAL MANAGEMENT, LLC pharmaceutical preparations | 3.40M | 2.29% | 2.29% | $6.56B | May 15, 2025 | ▲ 1.03M |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q1 2025 vs prior quarter
Q1 2025
27
Increased
+10.48M shares2
New Positions
first time holders13
Decreased
−6.07M shares0
Sold Out
fully exitedNet shares change (top 50)
+4.42M
+10.48M / −6.07M
Net new holders
+16
2 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
ANNX insider trading · insider activity
Source: SEC Form 4
Insiders have been net buyers of shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
3
Buy transactions
0
Sell transactions
0.00
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Satter Muneer A director | May 28, 2026 | Purchase | 613,497 | $5.41 | $3.32M | 10.34M | Form 4 ↗ |
Carson William H. director | May 11, 2026 | Purchase | 8,000 | $5.78 | $46.2K | 78.4K | Form 4 ↗ |
Carson William H. director | Apr 10, 2026 | Purchase | 8,000 | $6.20 | $49.6K | 70.4K | Form 4 ↗ |
Carson William H. director | Mar 10, 2026 | Purchase | 8,000 | $5.67 | $45.4K | 62.4K | Form 4 ↗ |
Dananberg Jamie CHIEF MEDICAL OFFICER | Mar 2, 2026 | Sale | 5,820 | $5.43 | $31.6K | 123.6K | Form 4 ↗ |
Overdorf Michael EVP & CHIEF BUSINESS OFFICER | Mar 2, 2026 | Sale | 4,339 | $5.42 | $23.5K | 182.6K | Form 4 ↗ |
Yednock Ted EVP & CHIEF INNOVATION OFFICER | Mar 2, 2026 | Sale | 5,566 | $5.42 | $30.2K | 154.2K | Form 4 ↗ |
ARTIS DEAN RICHARD EVP & CHIEF SCIENTIFIC OFFICER | Mar 2, 2026 | Sale | 5,894 | $5.43 | $32.0K | 180.1K | Form 4 ↗ |
Lew Jennifer EVP & CHIEF FINANCIAL OFFICER | Mar 2, 2026 | Sale | 5,565 | $5.42 | $30.2K | 170.7K | Form 4 ↗ |
Love Douglas PRESIDENT AND CEO | Feb 19, 2026 | Award | 1,250,000 | $5.10 | $6.38M | 1.25M | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
Annexon, Inc. (ANNX) is primarily owned by institutional investors, who hold approximately 83.4% of total shares outstanding. Company insiders own approximately 0.00%, while retail and public investors account for the remaining 23.74%.
The largest institutional shareholder of Annexon, Inc. is FMR LLC, holding approximately 13.26 million shares — equal to 8.95% of outstanding shares — as of March 31, 2025.
A total of 152 institutional investors currently hold ANNX stock, with a combined institutional value of approximately $192,194,831 as of the most recent 13F filing period.
Frequently asked questions
ANNX ownershipAnnexon, Inc. (ANNX) is primarily owned by institutional investors, who hold approximately 83.4% of shares. The largest shareholder is FMR LLC with a 8.95% stake. Company insiders hold 0.00%. Data sourced from SEC Form 13F as of March 31, 2025.