BIIB · NASDAQ · CIK 0000875045
Biogen Inc.
Biogen Inc. holds 1 disclosed position, 0 of them carrying a sourced value and 1 that nobody has sized.
Biogen Inc. - Profile
- Sector
- Health CareGICS
- Industry
- Biological Products, (No Diagnostic Substances)SIC 2836
- Listed on
- Nasdaq
- Employees
- 7,500stated 2025
- Incorporated in
- Delaware
- Financial year ends
- 31 December
Source
Address, industry classification, listing and incorporation come from Biogen Inc.'s own SEC filer record, so the industry is the SEC's dry classification rather than a marketing label. The website comes from Wikidata. The headcount is the figure the Wikipedia article states for 2025, not a figure this site has verified against a filing. The description is the opening paragraph of its Wikipedia article, used under CC BY-SA 4.0.
Share price
BIIB
Description
Biogen Inc. is an American multinational biotechnology company based in Cambridge, Massachusetts, United States specializing in the treatment of neurological diseases. The company's primary products are dimethyl fumarate (Tecfidera), diroximel fumarate (Vumerity), interferon beta-1a (AVONEX), peginterferon beta-1a (Plegridy), and natalizumab (Tysabri), all for the treatment of multiple sclerosis (collectively 45% of 2024 revenues); nusinersen (Spinraza) for the treatment of spinal muscular atrophy (16.2% of 2024 revenues); omaveloxolone (Skyclarys) for the treatment of Friedreich's ataxia (4.0% of 2024 revenues); tofersen (Qalsody) for the treatment of ALS; and dimethyl fumarate (Fumaderm) f…
Equity stakes Biogen Inc. holds in other companies.
No position on this side carries a sourced value, so there is nothing to chart. The table still lists 1 of them.
Select a row or a slice for its provenance: the filing it came from, when it was measured, and the arithmetic behind it if it was modelled.
The full register, from 13F filings
The Register tab above is hand research: a dozen holders, each traced to the filing it came from. This asks the same question of the whole market for the quarter ended 31-mar-2026, where 988 managers reported a position. Broad where the research is deep, and shallow in the ways a 13F always is.
988 managers reported a position, together holding 134.3m shares, or 90.9% of the company. The 40 largest are listed. Percentages are of a share count taken later than this quarter, because the count in force at the snapshot is not published as a structured fact for this company. Where the count has moved since, the figures are off by that much.
Built from 13F filings, which report US listed, long, US custodied positions only. A register from this source is a floor rather than a level: a holder's true position can be far larger, as BlackRock's ASML stake shows at 1.28m shares in a 13F against 26.3m in its 13G/A. Holdings held through derivatives, outside US custody, or below a manager's reporting obligation do not appear. Where a holder is marked as a family, its total sums several separate filing entities and describes something no single filing describes; the constituent entities and their share counts are listed so the total can be checked. That roll-up can legitimately exceed the family's own Schedule 13G, because a 13G is filed by one legal entity: Vanguard reports Alphabet through ten advisory entities, and The Vanguard Group Inc itself reported zero after its January 2026 disaggregation.
What a reader needs to know to read these numbers
- Combined-balance trap: Biogen's 'strategic investment portfolio' ($248.7m as of 30 Jun 2026, $186.6m as of 31 Dec 2025, $226.7m as of 31 Dec 2024) is a single balance sheet figure covering Denali common stock, venture capital funds invested in biotech equity securities, and non-marketable equity securities together. No individual holding's value can be extracted from it, so Denali's holdings row carries value_usd: null with the combined figures recorded here rather than assigned to Denali.
- Samsung Bioepis: Biogen sold its entire 49.9% joint-venture equity interest in Samsung Bioepis Co., Ltd. to Samsung BioLogics in April 2022 for approximately $2.3 billion total consideration. This is a confirmed full exit; no holdings row is carried. Biogen retains only commercial/licensing collaboration arrangements with Samsung Bioepis (e.g. biosimilars profit-sharing), not an equity stake. Source: FY2025 10-K, Note 3 Dispositions.
- Sage Therapeutics (now Supernus Pharmaceuticals, Inc., which acquired Sage): Biogen fully sold its remaining investment in Sage common stock during the third quarter of 2025. Confirmed full exit via the FY2025 10-K and Schedule 13D/A filings (2025-07-21, 2025-07-30) on Sage Therapeutics' own CIK. No holdings row is carried.
- Apellis Pharmaceuticals: Biogen entered an Agreement and Plan of Merger dated 31 Mar 2026 to acquire Apellis Pharmaceuticals via cash tender offer. A Schedule 13D filed 2026-04-06 showed an interim stake of 18,469,475 shares (14.2%) accumulated during the offer; a Schedule 13D/A filed 2026-05-14 showed 0 shares, consistent with the tender offer/merger having closed and Apellis becoming a wholly owned Biogen subsidiary. Wholly owned operating subsidiaries are excluded from holdings per the research brief; no row is carried.
- Reata Pharmaceuticals, Human Immunology Biosciences (HI-Bio), and Alcyone Therapeutics were all acquired outright by Biogen (Reata 2023, HI-Bio and Alcyone 2024) and are wholly owned subsidiaries, not minority equity holdings; excluded per the research brief.
- Capital Group: all three primary 13F registrants (Capital World Investors CIK 0001422849, Capital International Investors CIK 0001562230, Capital Research Global Investors CIK 0001422848) were checked individually against their Form 13F-HR for the quarter ended 30 Jun 2026 and none holds any Biogen position (no row matched CUSIP 09062X103 or 'BIOGEN' in any of the three information tables). Checked and found at zero; no row carried per the database convention that null rows mean 'not sized', not 'holds nothing'.
- Self-gate computed on the final file exactly as the chart computes it: no register row has rolls_up_into or is_aggregate set (the insider group row stands alone with no members counted separately), so total = raw sum of all 10 rows = 17,817,720 + 18,217,239 + 15,985,736 + 15,154,606 + 7,344,327 + 4,449,295 + 2,411,271 + 1,823,140 + 774,283 + 367,802 = 84,345,419 shares against 147,753,998 shares outstanding = 57.09%. This is above the brief's rough 55% ceiling; cross-checked against reported institutional ownership of 97.16% of the float (stockanalysis.com), which makes a top-9-institution-plus-insiders concentration of 57% plausible rather than a sign of double-counting. No duplicate holder or mixed-basis issue was found on review.
- No em dashes used in any text field per house style.
Looked for, not found
Recorded rather than filled in. Each of these is a place where a number could have been invented and was not.
- Denali Therapeutics current share count and dollar value of Biogen's holding: not disclosed after Biogen MA Inc.'s Schedule 13G/A filed 2024-11-07 (7,155,243 shares, 4.97%). No subsequent 13G/A found via EDGAR full-text search through 19 Aug 2026. The 10-K/10-Q confirm the position is still real and increased in fair value in H1 2026, but it is embedded in a combined balance that cannot be disaggregated.
- Sangamo Therapeutics: Biogen last disclosed holding 3,250,000 shares (1.6%) in a Schedule 13G/A filed 2024-08-16. Not mentioned in the FY2025 10-K's or Q2 2026 10-Q's current-period equity-securities discussion (which names only Denali, and historically Sage). No subsequent 13G/A found. Could not confirm whether this position is still held, reduced, or fully exited; not included as a holdings row given that uncertainty.
- Ionis Pharmaceuticals: Biogen purchased approximately 11.5 million shares of Ionis common stock in 2018 for $625.0 million as part of a collaboration agreement. Last Schedule 13G/A on file (via Ionis' own CIK 0000874015) was filed 2020-02-11. Not mentioned in the FY2025 10-K's current-period equity-securities discussion. Could not confirm current holding status; likely divested given the age of the last filing and its absence from recent disclosures, but no explicit sale statement was located in the filings searched.
- Neurimmune SubOne AG: a private Swiss company and longstanding royalty/licensing collaborator (source of the antibody technology behind ADUHELM/aducanumab and related programs). No equity investment by Biogen in Neurimmune was found in the FY2025 10-K or Q2 2026 10-Q text searched; treated as a licensing relationship only, not a holding.
- Biogen does not appear to file its own Form 13F (no 13F-HR or 13F-NT found under CIK 0000875045 in EDGAR submissions), consistent with it not being an institutional investment manager; individual position filings (13D/13G) were used instead where available.
- Register: aimed for 8 to 12 holders per the brief; nine institutional/family rows plus one insider-group row were sourced. Smaller holders beyond the top ~10 (e.g. AQR, Invesco, Boston Partners, Northern Trust, UBS, Legal & General per the 31-Mar-2026 register snapshot) were not individually refreshed to fresh Q2 2026 13F data given time budget; their approximate 31-Mar-2026 positions are in data/registers/BIIB.json but were not re-verified here.