Biogen Inc.
MX ˙ BMV ˙ US09062X1037
SecurityMX:BIIB / Biogen Inc.
InstitutionRegions Financial Corp
Latest Disclosed Ownership1,188 shares
Latest Disclosed Value $ 217,797
Regions Financial Corp reports 3.96% decrease in ownership of BIIB / Biogen Inc.

On May 5, 2026 - Regions Financial Corp filed a 13F-HR form disclosing ownership of 1,188 shares of Biogen Inc. (MX:BIIB) valued at $217,797 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 27, 2026 disclosing 1,237 shares of Biogen Inc.. This represents a change in shares of -3.96% 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)
2026-05-05 2026-03-31 13F BIOGEN COM 09062X103 1,188 -49 -3.96 218 0.00 0.0014
2026-01-27 2025-12-31 13F BIOGEN COM 09062X103 1,237 1,237 218 0.0014
2025-05-08 2025-03-31 13F Biogen COM 09062X103 0 -1,354 -100.00 0 -100.00
2025-02-14 2024-12-31 13F Biogen COM 09062X103 1,354 -340 -20.07 207 -36.89 0.0015
2024-11-14 2024-09-30 13F Biogen COM 09062X103 1,694 -1 -0.06 328 -16.33 0.0024
2024-07-31 2024-06-30 13F Biogen COM 09062X103 1,695 -643 -27.50 393 -22.22 0.0030
2024-04-23 2024-03-31 13F Biogen COM 09062X103 2,338 465 24.83 504 4.13 0.0038
2024-02-06 2023-12-31 13F Biogen COM 09062X103 1,873 -66 -3.40 485 -2.81 0.0040
2023-11-01 2023-09-30 13F Biogen COM 09062X103 1,939 -249 -11.38 498 -20.06 0.0045
2023-08-09 2023-06-30 13F Biogen COM 09062X103 2,188 -55 -2.45 623 0.0054
2023-05-12 2023-03-31 13F Biogen COM 09062X103 2,243 219 10.82 1 0.0056
2023-02-06 2022-12-31 13F Biogen COM 09062X103 2,024 -24 -1.17 1 -100.00 0.0052
2022-11-03 2022-09-30 13F Biogen COM 09062X103 2,048 -90 -4.21 546 25.23 0.0055
2022-07-25 2022-06-30 13F Biogen COM 09062X103 2,138 -5,781 -73.00 436 -73.85 0.0041
2022-04-25 2022-03-31 13F Biogen COM 09062X103 7,919 -455 -5.43 1,667 -17.02 0.0135
2022-01-31 2021-12-31 13F Biogen COM 09062X103 8,374 4,246 102.86 2,009 72.00 0.0157
2021-11-04 2021-09-30 13F Biogen COM 09062X103 4,128 -1,063 -20.48 1,168 -35.00 0.0101
2021-07-27 2021-06-30 13F Biogen COM 09062X103 5,191 -10,228 -66.33 1,797 -58.34 0.0155
2021-06-02 2021-03-31 13F Biogen COM 09062X103 15,419 -25,367 -62.20 4,314 -56.80 0.0391
2021-02-05 2020-12-31 13F Biogen COM 09062X103 40,786 -2,931 -6.70 9,987 -19.47 0.0963
2020-10-15 2020-09-30 13F Biogen COM 09062X103 43,717 2,073 4.98 12,402 11.32 0.1353
2020-07-27 2020-06-30 13F Biogen COM 09062X103 41,644 11,988 40.42 11,141 18.74 0.1297
2020-04-29 2020-03-31 13F Biogen COM 09062X103 29,656 27,890 1,579.28 9,383 1,690.65 0.1249
2020-02-03 2019-12-31 13F Biogen COM 09062X103 1,766 -60 -3.29 524 23.29 0.0055
2019-10-24 2019-09-30 13F Biogen COM 09062X103 1,826 -518 -22.10 425 -22.45 0.0047
2019-07-19 2019-06-30 13F Biogen COM 09062X103 2,344 -302 -11.41 548 -12.32 0.0062
2019-04-19 2019-03-31 13F Biogen COM 09062X103 2,646 -163 -5.80 625 -26.04 0.0072
2019-01-28 2018-12-31 13F Biogen COM 09062X103 2,809 -66 -2.30 845 -16.75 0.0106
2018-10-22 2018-09-30 13F Biogen COM 09062X103 2,875 -27 -0.93 1,015 20.40 0.0109
2018-07-26 2018-06-30 13F Biogen COM 09062X103 2,902 -72 -2.42 843 3.44 0.0095
2018-04-18 2018-03-31 13F Biogen COM 09062X103 2,974 -327 -9.91 815 -22.53 0.0091
2018-01-18 2017-12-31 13F Biogen COM 09062X103 3,301 90 2.80 1,052 4.57 0.0114
2017-10-23 2017-09-30 13F BIOGEN COMMON STOCK 09062X103 3,211 -1,840 -36.43 1,006 -26.57 0.0114
2017-07-31 2017-06-30 13F BIOGEN COMMON STOCK 09062X103 5,051 76 1.53 1,370 0.74 0.0161
2017-05-02 2017-03-31 13F BIOGEN COMMON STOCK 09062X103 4,975 -130 -2.55 1,360 -6.08 0.0161
2017-02-03 2016-12-31 13F BIOGEN COMMON STOCK 09062X103 5,105 33 0.65 1,448 -8.82 0.0177
2016-10-28 2016-09-30 13F BIOGEN COMMON STOCK 09062X103 5,072 135 2.73 1,588 33.11 0.0205
2016-07-26 2016-06-30 13F BIOGEN COMMON STOCK 09062X103 4,937 -392 -7.36 1,193 -13.99 0.0155
2016-05-02 2016-03-31 13F BIOGEN COMMON STOCK 09062X103 5,329 -672 -11.20 1,387 -24.54 0.0184
2016-01-29 2015-12-31 13F BIOGEN COMMON STOCK 09062X103 6,001 -808 -11.87 1,838 -7.50 0.0247
2015-10-20 2015-09-30 13F BIOGEN COMMON STOCK 09062X103 6,809 -2,066 -23.28 1,987 -44.57 0.0283
2015-07-14 2015-06-30 13F BIOGEN COMMON STOCK 09062X103 8,875 530 6.35 3,585 1.73 0.0476
2015-04-23 2015-03-31 13F BIOGEN COMMON STOCK 09062X103 8,345 105 1.27 3,524 25.99 0.0453
2015-01-21 2014-12-31 13F BIOGEN IDEC COMMON STOCK 09062X103 8,240 -25,964 -75.91 2,797 -75.28 0.0363
2014-10-27 2014-09-30 13F BIOGEN IDEC COMMON STOCK 09062X103 34,204 -1,039 -2.95 11,315 1.83 0.1411
2014-07-23 2014-06-30 13F BIOGEN IDEC COMMON STOCK 09062X103 35,243 1,013 2.96 11,112 6.13 0.1361
2014-04-17 2014-03-31 13F BIOGEN IDEC COMMON STOCK 09062X103 34,230 -2,165 -5.95 10,470 2.90 0.1328
2014-01-27 2013-12-31 13F BIOGEN IDEC COMMON STOCK 09062X103 36,395 -6,325 -14.81 10,175 -1.07 0.1257
2013-10-18 2013-09-30 13F BIOGEN IDEC COMMON STOCK 09062X103 42,720 -3,333 -7.24 10,285 3.77 0.1359
2013-08-02 2013-06-30 13F BIOGEN IDEC COM 09062X103 46,053 46,053 9,911 0.1351
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.