argenx SE - Depositary Receipt (Common Stock)
US ˙ NasdaqGS ˙ US04016X1019

SecurityARGX / argenx SE - Depositary Receipt (Common Stock)
InstitutionSei Investments Co
Latest Disclosed Ownership330,506 shares
Latest Disclosed Value $ 277,936,826
Sei Investments Co reports 5.84% increase in ownership of ARGX / argenx SE - Depositary Receipt (Common Stock)

On February 13, 2026 - Sei Investments Co filed a 13F-HR form disclosing ownership of 330,506 shares of argenx SE - Depositary Receipt (Common Stock) (US:ARGX) valued at $277,939,021 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 13, 2025 disclosing 312,268 shares of argenx SE - Depositary Receipt (Common Stock). This represents a change in shares of 5.84% during the quarter. The current value of the position is $268,747,649 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)
2026-02-13 2025-12-31 13F ARGENX SE SPONSORED ADR 04016X101 330,506 18,238 5.84 277,937 20.68 0.2743
2025-11-13 2025-09-30 13F ARGENX SE SPONSORED ADR 04016X101 312,268 -4,131 -1.31 230,318 32.06 0.2477
2025-08-14 2025-06-30 13F ARGENX SE SPONSORED ADR 04016X101 316,399 -44,601 -12.35 174,404 -18.37 0.2022
2025-05-14 2025-03-31 13F/A-1 ARGENX SE SPONSORED ADR 04016X101 361,000 -5,620 -1.53 213,662 -5.24 0.2750
2025-05-13 2025-03-31 13F ARGENX SE SPONSORED ADR 04016X101 367,751 1,131 225,998 0.2458
2025-02-11 2024-12-31 13F ARGENX SE SPONSORED ADR 04016X101 366,620 -14,075 -3.70 225,475 9.26 0.2896
2024-11-12 2024-09-30 13F ARGENX SE SPONSORED ADR 04016X101 380,695 -849 -0.22 206,366 25.77 0.2680
2024-08-13 2024-06-30 13F ARGENX SE SPONSORED ADR 04016X101 381,544 50,477 15.25 164,079 25.88 0.2325
2024-05-07 2024-03-31 13F ARGENX SE SPONSORED ADR 04016X101 331,067 -950 -0.29 130,347 3.20 0.1910
2024-02-14 2023-12-31 13F ARGENX SE SPONSORED ADR 04016X101 332,017 45,707 15.96 126,309 -10.26 0.2028
2023-11-14 2023-09-30 13F ARGENX SE SPONSORED ADR 04016X101 286,310 26,152 10.05 140,757 38.82 0.2529
2023-08-11 2023-06-30 13F ARGENX SE SPONSORED ADR 04016X101 260,158 -6,716 -2.52 101,392 1.97 0.1769
2023-05-12 2023-03-31 13F ARGENX SE SPONSORED ADR 04016X101 266,874 95,489 55.72 99,433 53.15 0.1847
2023-02-10 2022-12-31 13F ARGENX SE SPONSORED ADR 04016X101 171,385 -8,098 -4.51 64,927 2.46 0.1443
2022-11-14 2022-09-30 13F ARGENX SE SPONSORED ADR 04016X101 179,483 3,330 1.89 63,367 -5.11 0.1413
2022-08-15 2022-06-30 13F ARGENX SE SPONSORED ADR 04016X101 176,153 -18,978 -9.73 66,776 8.47 0.1442
2022-05-13 2022-03-31 13F ARGENX SE SPONSORED ADR 04016X101 195,131 15,411 8.58 61,561 -2.17 0.1237
2022-02-14 2021-12-31 13F ARGENX SE SPONSORED ADR 04016X101 179,720 29,719 19.81 62,929 38.90 0.1181
2021-11-12 2021-09-30 13F ARGENX SE SPONSORED ADR 04016X101 150,001 7,964 5.61 45,304 5.94 0.0950
2021-08-06 2021-06-30 13F ARGENX SE SPONSORED ADR 04016X101 142,037 14,468 11.34 42,765 21.73 0.0948
2021-05-12 2021-03-31 13F ARGENX SE SPONSORED ADR 04016X101 127,569 42,709 50.33 35,131 40.77 0.0885
2021-02-08 2020-12-31 13F ARGENX SE SPONSORED ADR 04016X101 84,860 31,176 58.07 24,956 77.08 0.0645
2020-12-04 2020-09-30 13F/A-1 ARGENX SE SPONSORED ADR 04016X101 53,684 12,744 31.13 14,093 52.84 0.0408
2020-11-06 2020-09-30 13F ARGENX SE SPONSORED ADR 04016X101 53,688 12,748 14,094 33,935.2184
2020-08-17 2020-06-30 13F/A-1 ARGENX SE SPONSORED ADR 04016X101 40,940 4,139 11.25 9,221 90.20 0.0286
2020-08-11 2020-06-30 13F ARGENX SE SPONSORED ADR 04016X101 25,919 -10,882 4,161 11,286.9340
2020-05-14 2020-03-31 13F ARGENX SE SPONSORED ADR 04016X101 36,801 10,882 41.98 4,848 16.51 0.0178
2020-02-06 2019-12-31 13F ARGENX SE SPONSORED ADR 04016X101 25,919 -1,047 -3.88 4,161 35.41 0.0124
2019-11-12 2019-09-30 13F ARGENX SE SPONSORED ADR 04016X101 26,966 3,303 13.96 3,073 -8.27 0.0079
2019-08-14 2019-06-30 13F ARGENX SE SPONSORED ADR 04016X101 23,663 10,821 84.26 3,350 108.98 0.0109
2019-05-15 2019-03-31 13F ARGENX SE SPONSORED ADR 04016X101 12,842 12,842 1,603 0.0054
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.