<SEC-DOCUMENT>0001193125-20-118235-index.html : 20200424
<SEC-HEADER>0001193125-20-118235.hdr.sgml : 20200424
<ACCEPTANCE-DATETIME>20200424082823
ACCESSION NUMBER:		0001193125-20-118235
CONFORMED SUBMISSION TYPE:	S-3ASR
PUBLIC DOCUMENT COUNT:		10
FILED AS OF DATE:		20200424
DATE AS OF CHANGE:		20200424
EFFECTIVENESS DATE:		20200424

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BIOGEN INC.
		CENTRAL INDEX KEY:			0000875045
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				330112644
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		S-3ASR
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-237819
		FILM NUMBER:		20812575

	BUSINESS ADDRESS:	
		STREET 1:		225 BINNEY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		7814642000

	MAIL ADDRESS:	
		STREET 1:		225 BINNEY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BIOGEN IDEC INC.
		DATE OF NAME CHANGE:	20070427

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BIOGEN IDEC INC
		DATE OF NAME CHANGE:	20031112

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	IDEC PHARMACEUTICALS CORP / DE
		DATE OF NAME CHANGE:	19970530
</SEC-HEADER>
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<TYPE>S-3ASR
<SEQUENCE>1
<FILENAME>d880238ds3asr.htm
<DESCRIPTION>S-3ASR
<TEXT>
Document 1 - file: d880238ds3asr.htm

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<SEQUENCE>2
<FILENAME>d880238dex51.htm
<DESCRIPTION>EX-5.1
<TEXT>
Document 2 - file: d880238dex51.htm

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<DOCUMENT>
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<SEQUENCE>3
<FILENAME>d880238dex231.htm
<DESCRIPTION>EX-23.1
<TEXT>
Document 3 - file: d880238dex231.htm

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<DOCUMENT>
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<SEQUENCE>4
<FILENAME>d880238dex25.htm
<DESCRIPTION>EX-25
<TEXT>
Document 4 - file: d880238dex25.htm

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<DESCRIPTION>GRAPHIC
<TEXT>
Document 5 - file: g880238g01g44.jpg

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<DESCRIPTION>GRAPHIC
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Document 6 - file: g880238g02z45.jpg

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<SEQUENCE>7
<FILENAME>g880238g03w14.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 7 - file: g880238g03w14.jpg

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<TYPE>GRAPHIC
<SEQUENCE>8
<FILENAME>g880238g04n55.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 8 - file: g880238g04n55.jpg

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Document 9 - file: g880238g05x47.jpg

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<SEQUENCE>10
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<DESCRIPTION>GRAPHIC
<TEXT>
Document 10 - file: g880238g79x07.jpg

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