Annexon, Inc.
US ˙ NasdaqGS ˙ US03589W1027

SecurityANNX / Annexon, Inc.
InstitutionDimensional Fund Advisors Lp
Latest Disclosed Ownership924,078 shares
Latest Disclosed Value $ 5,115,464
Dimensional Fund Advisors Lp reports 28.58% increase in ownership of ANNX / Annexon, Inc.

On May 7, 2026 - Dimensional Fund Advisors Lp filed a 13F-HR form disclosing ownership of 924,078 shares of Annexon, Inc. (US:ANNX) valued at $5,119,392 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 718,680 shares of Annexon, Inc.. This represents a change in shares of 28.58% during the quarter. The current value of the position is $4,888,373 USD.

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)
2026-05-07 2026-03-31 13F ANNEXON COM 03589W102 924,078 205,398 28.58 5,115 41.81 0.0002
2026-02-12 2025-12-31 13F ANNEXON COM 03589W102 718,680 -48,275 -6.29 3,608 54.21 0.0008
2025-11-12 2025-09-30 13F ANNEXON COM 03589W102 766,955 -122,908 -13.81 2,340 9.56 0.0005
2025-08-12 2025-06-30 13F ANNEXON COM 03589W102 889,863 -97,016 -9.83 2,136 12.01 0.0005
2025-05-13 2025-03-31 13F ANNEXON COM 03589W102 986,879 -373,197 -27.44 1,907 -72.68 0.0005
2025-02-13 2024-12-31 13F ANNEXON COM 03589W102 1,360,076 231,034 20.46 6,977 4.37 0.0017
2024-11-07 2024-09-30 13F ANNEXON COM 03589W102 1,129,042 306,437 37.25 6,685 65.88 0.0016
2024-08-09 2024-06-30 13F ANNEXON COM 03589W102 822,605 488,692 146.35 4,030 68.34 0.0011
2024-05-10 2024-03-31 13F ANNEXON COM 03589W102 333,913 246,866 283.60 2,394 506.08 0.0006
2024-02-07 2023-12-31 13F ANNEXON COM 03589W102 87,047 28,525 48.74 395 186.23 0.0001
2023-11-09 2023-09-30 13F ANNEXON COM 03589W102 58,522 16 0.03 138 -32.68 0.0000
2023-08-09 2023-06-30 13F ANNEXON COM 03589W102 58,506 -20 -0.03 206 -8.89 0.0001
2023-05-12 2023-03-31 13F ANNEXON COM 03589W102 58,526 1,370 2.40 225 0.0001
2023-02-09 2022-12-31 13F ANNEXON COM 03589W102 57,156 20 0.04 0 -100.00 0.0001
2022-11-10 2022-09-30 13F ANNEXON COM 03589W102 57,136 30,605 115.36 353 253.00 0.0001
2022-08-12 2022-06-30 13F ANNEXON COM 03589W102 26,531 -2,138 -7.46 100 28.21 0.0000
2022-05-13 2022-03-31 13F ANNEXON COM 03589W102 28,669 0 0.00 78 -76.29 0.0000
2022-02-09 2021-12-31 13F ANNEXON COM 03589W102 28,669 28,669 329 0.0001
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.