百健公司
MX ˙ BMV ˙ US09062X1037
SecurityMX:BIIB / Biogen Inc.
InstitutionSei Investments Co
Latest Disclosed Ownership59,496 shares
Latest Disclosed Value $ 10,470,544
Sei Investments Co reports 160.59% increase in ownership of BIIB / Biogen Inc.

On February 13, 2026 - Sei Investments Co filed a 13F-HR form disclosing ownership of 59,496 shares of Biogen Inc. (MX:BIIB) valued at $10,470,544 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 13, 2025 disclosing 22,831 shares of Biogen Inc.. This represents a change in shares of 160.59% 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.

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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 BIOGEN COM 09062X103 59,496 36,665 160.59 10,471 227.49 0.0103
2025-11-13 2025-09-30 13F BIOGEN COM 09062X103 22,831 803 3.65 3,198 15.58 0.0034
2025-08-14 2025-06-30 13F BIOGEN COM 09062X103 22,028 3,713 20.27 2,767 10.38 0.0032
2025-05-14 2025-03-31 13F/A-1 BIOGEN COM 09062X103 18,315 -14,379 -43.98 2,506 -49.87 0.0032
2025-05-13 2025-03-31 13F BIOGEN COM 09062X103 32,324 -370 4,895 0.0053
2025-02-11 2024-12-31 13F BIOGEN COM 09062X103 32,694 -75,258 -69.71 4,999 -76.11 0.0064
2024-11-12 2024-09-30 13F BIOGEN COM 09062X103 107,952 2,601 2.47 20,926 -14.32 0.0272
2024-08-13 2024-06-30 13F BIOGEN COM 09062X103 105,351 14,900 16.47 24,422 25.22 0.0346
2024-05-07 2024-03-31 13F BIOGEN COM 09062X103 90,451 837 0.93 19,505 -15.90 0.0286
2024-02-14 2023-12-31 13F BIOGEN COM 09062X103 89,614 -2,182 -2.38 23,192 -1.70 0.0372
2023-11-14 2023-09-30 13F BIOGEN COM 09062X103 91,796 535 0.59 23,592 -9.24 0.0424
2023-08-11 2023-06-30 13F BIOGEN COM 09062X103 91,261 -10,154 -10.01 25,992 -7.82 0.0453
2023-05-12 2023-03-31 13F BIOGEN COM 09062X103 101,415 3,983 4.09 28,197 4.52 0.0524
2023-02-10 2022-12-31 13F BIOGEN COM 09062X103 97,432 -6,426 -6.19 26,979 -2.71 0.0600
2022-11-14 2022-09-30 13F BIOGEN COM 09062X103 103,858 -7,264 -6.54 27,730 22.50 0.0619
2022-08-15 2022-06-30 13F BIOGEN COM 09062X103 111,122 -110,221 -49.80 22,637 -51.41 0.0489
2022-05-13 2022-03-31 13F BIOGEN COM 09062X103 221,343 -32,617 -12.84 46,591 -23.43 0.0936
2022-02-14 2021-12-31 13F BIOGEN COM 09062X103 253,960 44,012 20.96 60,849 2.24 0.1142
2021-11-12 2021-09-30 13F BIOGEN COM 09062X103 209,948 126,096 150.38 59,513 105.54 0.1249
2021-08-06 2021-06-30 13F BIOGEN COM 09062X103 83,852 -16,469 -16.42 28,954 6.93 0.0642
2021-05-12 2021-03-31 13F BIOGEN COM 09062X103 100,321 1,161 1.17 27,078 11.64 0.0682
2021-02-08 2020-12-31 13F BIOGEN COM 09062X103 99,160 -24,230 -19.64 24,255 -30.69 0.0627
2020-12-04 2020-09-30 13F/A-1 BIOGEN COM 09062X103 123,390 -1,930 -1.54 34,996 4.13 0.1013
2020-11-06 2020-09-30 13F BIOGEN COM 09062X103 126,204 884 35,794 86,183.9936
2020-08-17 2020-06-30 13F/A-1 BIOGEN COM 09062X103 125,320 -791 -0.63 33,609 -15.77 0.1043
2020-08-11 2020-06-30 13F BIOGEN COM 09062X103 133,082 6,971 38,411 104,191.8821
2020-05-14 2020-03-31 13F BIOGEN COM 09062X103 126,111 -541 -0.43 39,902 6.14 0.1466
2020-02-06 2019-12-31 13F BIOGEN COM 09062X103 126,652 8,462 7.16 37,594 37.73 0.1121
2019-11-12 2019-09-30 13F BIOGEN COM 09062X103 118,190 11,886 11.18 27,295 10.58 0.0698
2019-08-14 2019-06-30 13F BIOGEN COM 09062X103 106,304 -10,827 -9.24 24,683 -10.35 0.0806
2019-05-15 2019-03-31 13F BIOGEN COM 09062X103 117,131 -16,545 -12.38 27,533 -40.64 0.0925
2019-02-13 2018-12-31 13F BIOGEN COM 09062X103 133,676 5,394 4.20 46,383 2.40 0.1651
2018-11-08 2018-09-30 13F BIOGEN COM 09062X103 128,282 -41,324 -24.36 45,294 -7.98 0.1642
2018-08-03 2018-06-30 13F BIOGEN COM 09062X103 169,606 9,327 5.82 49,222 12.15 0.1673
2018-05-11 2018-03-31 13F BIOGEN COM 09062X103 160,279 -172,152 -51.79 43,889 -58.56 0.1682
2018-02-08 2017-12-31 13F BIOGEN COM 09062X103 332,431 9,809 3.04 105,904 4.84 0.3678
2017-11-06 2017-09-30 13F BIOGEN COM 09062X103 322,622 5,885 1.86 101,019 17.53 0.3591
2017-07-31 2017-06-30 13F BIOGEN COM 09062X103 316,737 -50,369 -13.72 85,949 -14.37 0.3426
2017-05-05 2017-03-31 13F BIOGEN COM 09062X103 367,106 75,587 25.93 100,373 21.42 0.4399
2017-02-02 2016-12-31 13F BIOGEN COM 09062X103 291,519 -37,329 -11.35 82,669 -19.69 0.4003
2016-11-04 2016-09-30 13F BIOGEN COM 09062X103 328,848 215,294 189.60 102,940 274.87 0.5229
2016-08-11 2016-06-30 13F BIOGEN COM 09062X103 113,554 -14,805 -11.53 27,460 -17.82 0.1647
2016-05-10 2016-03-31 13F/A-1 BIOGEN COM 09062X103 128,359 2,223 1.76 33,414 -13.53 0.2079
2016-02-03 2015-12-31 13F BIOGEN COM 09062X103 126,136 31,366 33.10 38,642 39.73 0.2355
2015-11-02 2015-09-30 13F/A-1 BIOGEN IDEC COM 09062X103 94,770 -102,471 -51.95 27,655 -65.29 0.2538
2015-10-30 2015-09-30 13F BIOGEN IDEC COM 09062X103 94,770 27,656
2015-08-07 2015-06-30 13F/A-1 BIOGEN IDEC COM 09062X103 197,241 -66,825 -25.31 79,674 -28.54 0.7203
2015-08-04 2015-06-30 13F BIOGEN IDEC COM 09062X103 197,241 -66,825 79,674 0.7203
2015-05-14 2015-03-31 13F/A-1 BIOGEN IDEC COM 09062X103 264,066 -70,754 -21.13 111,494 -1.89 0.9682
2015-05-01 2015-03-31 13F BIOGEN IDEC COM 09062X103 264,066 111,494
2015-02-10 2014-12-31 13F BIOGEN IDEC COM 09062X103 334,820 334,820 113,647 1.0045
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.