Biogen Inc. SEC filings BIIB

Biogen Inc. has 1,001 filings in SEC EDGAR's recent list, going back to Oct 2, 2014. Its latest annual report, Form ARS, was filed on Apr 28, 2026 for the period ended Dec 31, 2025. The latest quarterly report (Form 10-Q) was filed on Oct 28, 2026, covering the quarter ended Sep 30, 2026. The most recent current report (Form 8-K) was filed on Oct 28, 2026 (results of operations). The company's fiscal year ends on December 31.

Biogen Inc. SEC filings
Form Description Filed Period
SC TO-T/A Filing May 14, 2026 —
SC TO-T/A Amendment no. 2 May 12, 2026 —
SC TO-T/A Amendment no. 1 May 6, 2026 —
SC TO-T Filing Apr 14, 2026 —
SC TO-C Schedule to Apr 7, 2026 —
SC TO-C Schedule to Apr 3, 2026 —
SC TO-C Filing Mar 31, 2026 —
SC TO-C Schedule to Mar 31, 2026 —
DEFR14A Filing Jun 13, 2023 —
EFFECT Filing Jul 12, 2022 —
EFFECT Filing May 26, 2022 —
CORRESP Letter to the SEC May 24, 2022 —
UPLOAD Letter from the SEC May 23, 2022 —
UPLOAD Letter from the SEC Jun 22, 2021 —
CORRESP Letter to the SEC Jun 21, 2021 —
UPLOAD Letter from the SEC Jun 17, 2021 —
CORRESP Letter to the SEC Jun 9, 2021 —
PX14A6G Filing May 28, 2021 —
UPLOAD Letter from the SEC May 13, 2021 —
CORRESP Letter to the SEC Apr 7, 2021 —
UPLOAD Letter from the SEC Mar 25, 2021 —
UPLOAD Letter from the SEC Jul 23, 2018 —
CORRESP Letter to the SEC Jun 28, 2018 —
UPLOAD Letter from the SEC Jun 18, 2018 —
PX14A6G Filing May 3, 2018 —
PX14A6G Filing Mar 27, 2018 —
UPLOAD Letter from the SEC May 25, 2017 —
CORRESP Letter to the SEC May 10, 2017 —
UPLOAD Letter from the SEC May 3, 2017 —
CORRESP Letter to the SEC Apr 4, 2017 —
UPLOAD Letter from the SEC Mar 23, 2017 —
NO ACT Auto-generated paper document Feb 23, 2017 Feb 16, 2017
CT ORDER Filing Mar 29, 2016 —

Showing 33 filings. Main filings leave out insider and ownership forms such as Form 4; choose a type above to see them. Each form opens on SEC.gov. Older filings are on SEC EDGAR.

Company profile

Industry
Biological Products, (No Diagnostic Substances) (SIC 2836)
Listed as
BIIB (Nasdaq)
Fiscal year ends
December 31
Incorporated in
DE
Headquarters
Cambridge, MA
SEC filer status
Large accelerated filer
SEC CIK
875045
Former names
BIOGEN IDEC INC. (until Mar 20, 2015); BIOGEN IDEC INC (until Apr 25, 2007); IDEC PHARMACEUTICALS CORP / DE (until Nov 12, 2003); IDEC PHARMACEUTICALS CORP / CA (until Feb 14, 1997)

Other Biological Products, (No Diagnostic Substances) companies

Source: SEC EDGAR filings. This is company-reported data, not investment advice.