Annexon, Inc.
US ˙ NasdaqGS ˙ US03589W1027

SecurityANNX / Annexon, Inc.
InstitutionVanguard Group Inc
Latest Disclosed Ownership0 shares
Ownership 0.00%
Vanguard Group Inc ownership in ANNX / Annexon, Inc.

2026-03-26 - Vanguard Group Inc has filed an SCHEDULE 13G/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 0 shares of Annexon, Inc. (US:ANNX). This represents 0.0 percent ownership of the company. In their previous filing dated 2025-10-30 , Vanguard Group Inc had reported owning 5,835,112 shares, indicating a decrease of -100.00 percent.

Institutional Ownership: 13D/G Filings

This table shows a history of the 13D/G filings made by the investor and/or investor group. Note that the share values in this table are not directly comparable to any numbers shown in the 13F table (if any).

File
Date
Effective
Date
Form Prev
Shares
Latest
Shares
ΔShares
(Percent)
Ownership
(Percent)
ΔOwnership
(Percent)
2026-03-26 2026-03-26 13G/A 5,835,112 0 -100.00 0.00 -100.00
2025-10-30 2025-10-30 13G 5,379,659 5,835,112 8.47 5.31 8.37
2025-04-30 2025-04-30 13G/A 5,546,918 5,379,659 -3.02 4.90 -5.77
2025-01-31 2025-01-31 13G 5,546,918 5.20

Important Note: One of the primary uses of the 13D/G filings is to evaluate the ability of a firm to control a company (ie, the "beneficial ownership"). To that end, firms are required to report not just direct holdings in companies, but indirect holdings that they control. For investment firms, these indirect holdings can include shares in funds they manage, advisory accounts, and in the case of activist campaigns, pledged votes. Therefore, share counts listed in 13D/G filings can differ significantly than share counts listed in 13F filings.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-01-29 2025-12-31 13F ANNEXON COM 03589W102 7,753,387 1,918,275 32.87 38,922 118.70 0.0006
2025-11-07 2025-09-30 13F ANNEXON COM 03589W102 5,835,112 469,073 8.74 17,797 38.20 0.0003
2025-08-11 2025-06-30 13F ANNEXON COM 03589W102 5,366,039 -13,620 -0.25 12,878 24.04 0.0002
2025-05-09 2025-03-31 13F ANNEXON COM 03589W102 5,379,659 -167,259 -3.02 10,383 -63.51 0.0002
2025-02-11 2024-12-31 13F ANNEXON COM 03589W102 5,546,918 576,625 11.60 28,456 -3.29 0.0005
2024-11-13 2024-09-30 13F ANNEXON COM 03589W102 4,970,293 413,653 9.08 29,424 31.79 0.0005
2024-08-13 2024-06-30 13F ANNEXON COM 03589W102 4,556,640 808,985 21.59 22,328 -16.91 0.0004
2024-05-10 2024-03-31 13F ANNEXON COM 03589W102 3,747,655 1,839,329 96.38 26,871 210.17 0.0005
2024-03-11 2023-12-31 13F/A-1 ANNEXON COM 03589W102 1,908,326 13,917 0.73 8,664 93.80 0.0002
2024-02-14 2023-12-31 13F ANNEXON COM 03589W102 1,908,326 13,917 8,664 0.0002
2023-12-18 2023-09-30 13F/A-1 ANNEXON COM 03589W102 1,894,409 144,639 8.27 4,471 -27.42 0.0001
2023-11-14 2023-09-30 13F ANNEXON COM 03589W102 1,894,409 144,639 4,471 0.0000
2023-08-14 2023-06-30 13F ANNEXON COM 03589W102 1,749,770 179,799 11.45 6,159 1.90 0.0001
2023-07-14 2023-03-31 13F/A-1 ANNEXON COM 03589W102 1,569,971 21,100 1.36 6,044 -24.52 0.0002
2023-05-15 2023-03-31 13F ANNEXON COM 03589W102 1,569,971 21,100 6,044 0.0000
2023-02-10 2022-12-31 13F ANNEXON COM 03589W102 1,548,871 8,404 0.55 8,008 -15.89 0.0002
2022-11-14 2022-09-30 13F ANNEXON COM 03589W102 1,540,467 241,273 18.57 9,520 94.37 0.0003
2022-08-12 2022-06-30 13F ANNEXON COM 03589W102 1,299,194 204,162 18.64 4,898 63.81 0.0001
2022-05-13 2022-03-31 13F ANNEXON COM 03589W102 1,095,032 19,722 1.83 2,990 -75.80 0.0001
2022-02-14 2021-12-31 13F ANNEXON COM 03589W102 1,075,310 54,452 5.33 12,355 -34.97 0.0003
2021-11-12 2021-09-30 13F ANNEXON COM 03589W102 1,020,858 117,921 13.06 18,999 -6.52 0.0005
2021-08-13 2021-06-30 13F ANNEXON COM 03589W102 902,937 60,646 7.20 20,325 -13.33 0.0005
2021-05-14 2021-03-31 13F ANNEXON COM 03589W102 842,291 76,641 10.01 23,450 22.36 0.0006
2021-02-12 2020-12-31 13F ANNEXON COM 03589W102 765,650 44,963 6.24 19,165 -12.03 0.0006
2020-11-16 2020-09-30 13F ANNEXON COM 03589W102 720,687 720,687 21,787 0.0007
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.