百健公司
MX ˙ BMV ˙ US09062X1037
SecurityMX:BIIB / Biogen Inc.
InstitutionSTF Management LP
Latest Disclosed Ownership804 shares
Latest Disclosed Value $ 141,496
STF Management LP reports 47.28% decrease in ownership of BIIB / Biogen Inc.

On February 5, 2026 - STF Management LP filed a 13F-HR form disclosing ownership of 804 shares of Biogen Inc. (MX:BIIB) valued at $141,496 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 12, 2025 disclosing 1,525 shares of Biogen Inc.. This represents a change in shares of -47.28% during the quarter.

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.

Upgrade to unlock premium data and export to Excel .

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)
2026-02-05 2025-12-31 13F Biogen COM 09062X103 804 -721 -47.28 141 -33.80 0.1328
2025-11-12 2025-09-30 13F Biogen COM 09062X103 1,525 7 0.46 214 12.11 0.0792
2025-08-07 2025-06-30 13F Biogen COM 09062X103 1,518 76 5.27 191 -3.55 0.0752
2025-05-13 2025-03-31 13F Biogen COM 09062X103 1,442 108 8.10 197 -2.96 0.0947
2025-02-12 2024-12-31 13F Biogen COM 09062X103 1,334 -758 -36.23 204 -49.88 0.0915
2024-11-12 2024-09-30 13F Biogen COM 09062X103 2,092 -215 -9.32 406 -24.16 0.1845
2024-08-09 2024-06-30 13F Biogen COM 09062X103 2,307 -95 -3.96 535 3.29 0.2255
2024-05-01 2024-03-31 13F Biogen COM 09062X103 2,402 -58 -2.36 518 -18.71 0.2247
2024-02-09 2023-12-31 13F BIOGEN COM 09062X103 2,460 91 3.84 637 4.61 0.2992
2023-11-03 2023-09-30 13F BIOGEN COM 09062X103 2,369 1,468 162.93 609 137.50 0.3232
2023-08-02 2023-06-30 13F BIOGEN COM 09062X103 901 -752 -45.49 257 -44.23 0.2764
2023-05-12 2023-03-31 13F BIOGEN COM 09062X103 1,653 693 72.19 460 73.21 0.3097
2023-02-14 2022-12-31 13F BIOGEN COM 09062X103 960 960 266 0.3817
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.