Biogen Inc.
DE ˙ DB ˙ US09062X1037
162,20 € ↑3,64 (2,30%)
2026-06-03
DEL PRIS
SecurityDE:IDP / Biogen Inc.
InstitutionAmundi
Latest Disclosed Ownership790,827 shares
Latest Disclosed Value $ 144,982,314
Amundi reports 38.15% increase in ownership of IDP / Biogen Inc.

On May 15, 2026 - Amundi filed a 13F-HR form disclosing ownership of 790,827 shares of Biogen Inc. (DE:IDP) valued at $122,775,892 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 572,429 shares of Biogen Inc.. This represents a change in shares of 38.15% during the quarter. The current value of the position is $128,272,139 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)
2026-05-15 2026-03-31 13F BIOGEN COM 09062X103 790,827 218,398 38.15 144,982 43.92 0.0166
2026-02-17 2025-12-31 13F BIOGEN COM 09062X103 572,429 -45,880 -7.42 100,742 5.76 0.0274
2025-11-14 2025-09-30 13F BIOGEN COM 09062X103 618,309 38,512 6.64 95,251 23.34 0.0306
2025-08-13 2025-06-30 13F BIOGEN COM 09062X103 579,797 -736,150 -55.94 77,223 -55.10 0.0267
2025-05-15 2025-03-31 13F BIOGEN COM 09062X103 1,315,947 98,957 8.13 172,007 -6.24 0.0626
2025-02-07 2024-12-31 13F BIOGEN COM 09062X103 1,216,990 319,478 35.60 183,461 12.13 0.0638
2024-11-13 2024-09-30 13F BIOGEN COM 09062X103 897,512 212,692 31.06 163,616 6.37 0.0603
2024-08-14 2024-06-30 13F BIOGEN COM 09062X103 684,820 -300,982 -30.53 153,817 -18.10 0.0590
2024-05-15 2024-03-31 13F BIOGEN COM 09062X103 985,802 -215,904 -17.97 187,815 -38.91 0.0807
2024-02-14 2023-12-31 13F BIOGEN COM 09062X103 1,201,706 108,182 9.89 307,444 7.20 0.1384
2023-11-14 2023-09-30 13F BIOGEN COM 09062X103 1,093,524 -93,789 -7.90 286,788 -15.38 0.1409
2023-08-14 2023-06-30 13F BIOGEN COM 09062X103 1,187,313 609,020 105.31 338,907 106.36 0.1714
2023-05-15 2023-03-31 13F BIOGEN COM 09062X103 578,293 -240,340 -29.36 164,229 -29.62 0.0885
2023-02-14 2022-12-31 13F BIOGEN COM 09062X103 818,633 169,737 26.16 233,335 37.41 0.1280
2022-11-14 2022-09-30 13F BIOGEN COM 09062X103 648,896 241,061 59.11 169,810 94.32 0.1007
2022-09-02 2022-06-30 13F/A-1 BIOGEN COM 09062X103 407,835 60,579 17.45 87,385 18.90 0.0701
2022-08-15 2022-06-30 13F BIOGEN COM 09062X103 407,835 60,579 87,385 0.0046
2022-05-16 2022-03-31 13F BIOGEN COM 09062X103 347,256 -456,338 -56.79 73,494 -61.36 0.0497
2022-02-14 2021-12-31 13F BIOGEN COM 09062X103 803,594 -51,409 -6.01 190,186 -21.40 0.1205
2021-11-15 2021-09-30 13F BIOGEN COM 09062X103 855,003 235,305 37.97 241,957 112,964.02 0.1695
2021-08-16 2021-06-30 13F BIOGEN COM 09062X103 619,698 619,698 215 0.1490
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.