Biogen Inc.
US ˙ NasdaqGS ˙ US09062X1037

SecurityBIIB / Biogen Inc.
InstitutionInceptionr Llc
Latest Disclosed Ownership2,248 shares
Latest Disclosed Value $ 412,126
Inceptionr Llc reports 53.90% decrease in ownership of BIIB / Biogen Inc.

On May 14, 2026 - Inceptionr Llc filed a 13F-HR form disclosing ownership of 2,248 shares of Biogen Inc. (US:BIIB) valued at $412,126 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 4,876 shares of Biogen Inc.. This represents a change in shares of -53.90% during the quarter. The current value of the position is $440,518 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)
2026-05-14 2026-03-31 13F BIOGEN COM 09062X103 2,248 -2,628 -53.90 412 -51.98 0.0992
2026-02-11 2025-12-31 13F BIOGEN COM 09062X103 4,876 -426 -8.03 858 15.63 0.2381
2025-11-13 2025-09-30 13F BIOGEN COM 09062X103 5,302 -4,198 -44.19 743 -37.80 0.1793
2025-08-12 2025-06-30 13F BIOGEN COM 09062X103 9,500 2,954 45.13 1,193 33.30 0.2760
2025-05-12 2025-03-31 13F BIOGEN COM 09062X103 6,546 741 12.76 896 0.90 0.2677
2025-02-06 2024-12-31 13F BIOGEN COM 09062X103 5,805 -889 -13.28 888 -31.61 0.1980
2024-11-08 2024-09-30 13F BIOGEN COM 09062X103 6,694 3,142 88.46 1,298 57.59 0.3168
2024-08-13 2024-06-30 13F BIOGEN COM 09062X103 3,552 -2,644 -42.67 823 -38.40 0.2324
2024-05-09 2024-03-31 13F BIOGEN COM 09062X103 6,196 3,727 150.95 1,336 109.40 0.3438
2024-02-08 2023-12-31 13F BIOGEN COM 09062X103 2,469 -898 -26.67 639 -26.24 0.4558
2023-11-14 2023-09-30 13F BIOGEN COM 09062X103 3,367 3,367 865 0.4908
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.