EX-21 4 biib-20201231xex21.htm EX-21
Exhibit 21
BIOGEN INC.
The following is a list of subsidiaries of Biogen Inc. as of December 31, 2020, omitting some subsidiaries which, considered in the aggregate, would not constitute a significant subsidiary.

SUBSIDIARY |  | STATE OR OTHER JURISDICTION OF INCORPORATION OR ORGANIZATION
Biogen Foundation Inc. |  | Massachusetts
Biogen MA Inc. |  | Massachusetts
Biogen Realty Corporation |  | Massachusetts
Biogen Realty Limited Partnership |  | Massachusetts
Biogen U.S. Corporation |  | Massachusetts
Biogen U.S. Limited Partnership |  | Massachusetts
Biogen (RTP) Realty LLC |  | Delaware
Biogen Chesapeake LLC |  | Delaware
Biogen Holding I LLC |  | Delaware
Biogen Holding II LLC |  | Delaware
Biogen Manufacturing Holding LLC |  | Delaware
Biogen New Ventures Inc. |  | Delaware
Biogen SRO Inc. |  | Delaware
Biogen Therapeutics Inc. |  | Delaware
Biogen U.S. Pacific LLC |  | Delaware
Biogen U.S. West Corporation |  | Delaware
Conforma Therapeutics Corporation |  | Delaware
Stromedix, Inc. |  | Delaware
Nightstar, Inc. |  | Delaware
Biogen (Argentina) SRL |  | Argentina
Biogen Australia PTY Ltd |  | Australia
Biogen Austria GmbH |  | Austria
Biogen Belgium N.V./S.A. |  | Belgium
Biogen International Holding Limited |  | Bermuda
Biogen (Bermuda) Technologies Ltd. |  | Bermuda
Biogen Brasil Produtos Farmaceuticos LTDA |  | Brazil
Biogen Canada Inc. |  | Canada
Biogen Chile SpA |  | Chile
Biogen Biotechnology (Shanghai) Co., Ltd |  | China
BIIB Colombia S.A.S. |  | Colombia
Biogen Pharma d.o.o. |  | Croatia
Biogen (Czech Republic) s.r.o. |  | Czech Republic
Biogen (Denmark) A/S |  | Denmark
Biogen Estonia OU |  | Estonia
Biogen Finland OY |  | Finland
Biogen France S.A.S. |  | France
Biogen GmbH |  | Germany
Biogen Hong Kong Limited |  | Hong Kong
Biogen Hungary KFT |  | Hungary
Biogen Idec Biotech India Pvt. Ltd. |  | India
Biogen Idec (Ireland) Ltd. |  | Ireland

Nightstar Europa Limited |  | Ireland
Biogen Italia S.R.L. |  | Italy
Biogen Japan Ltd. |  | Japan
Biogen Korea LLC |  | Korea
Biogen Latvia SIA |  | Latvia
Biogen Lithuania UAB |  | Lithuania
Biogen Luxembourg Holding S.a.r.l. |  | Luxembourg
Biogen Mexico S. de R.L. de C.V. |  | Mexico
Biogen Mexico Servicios S. de R.L. de C.V. |  | Mexico
Biogen NZ Biopharma Ltd. |  | New Zealand
Biogen Norway AS |  | Norway
Biogen Poland Sp. z.o.o. |  | Poland
Biogen Portugal Sociedade Farmaceutica, Unipessoal Lda. |  | Portugal
Biogen Slovakia s.r.o. |  | Slovak Republic
Biogen Pharma, farmacevtska in biotehnoloska druzba, d.o.o. |  | Slovenia
Biogen Spain, S.L. |  | Spain
Biogen Sweden AB |  | Sweden
Biogen International GmbH |  | Switzerland
Biogen International Neuroscience GmbH |  | Switzerland
Biogen Management Services GmbH |  | Switzerland
Biogen Swiss Investments GmbH |  | Switzerland
Biogen Swiss Manufacturing GmbH |  | Switzerland
Biogen Switzerland AG |  | Switzerland
Biogen Switzerland Holdings GmbH |  | Switzerland
Eidetica Biopharma GmbH |  | Switzerland
Biogen Taiwan Limited |  | Taiwan
Biogen B.V. |  | The Netherlands
Biogen Netherlands B.V. |  | The Netherlands
Biogen Idec Limited |  | United Kingdom
Biogen Idec Research Ltd. |  | United Kingdom
Convergence Pharmaceuticals Limited |  | United Kingdom
Convergence Pharmaceuticals Holdings Ltd. |  | United Kingdom
Old Convergence Pharmaceuticals Limited |  | United Kingdom
Silver Acquisition Co. Ltd. |  | United Kingdom
Nightstar Therapeutics Limited |  | United Kingdom
NightstaRx Limited |  | United Kingdom
Tungsten Bidco Limited |  | United Kingdom
Biogen Idec Uruguay SA |  | Uruguay