<SEC-DOCUMENT>0001193125-18-138875-index.html : 20180427
<SEC-HEADER>0001193125-18-138875.hdr.sgml : 20180427
<ACCEPTANCE-DATETIME>20180427161056
ACCESSION NUMBER:		0001193125-18-138875
CONFORMED SUBMISSION TYPE:	DEFA14A
PUBLIC DOCUMENT COUNT:		7
FILED AS OF DATE:		20180427
DATE AS OF CHANGE:		20180427
EFFECTIVENESS DATE:		20180427

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:		DEFA14A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19311
		FILM NUMBER:		18783960

	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>DEFA14A
<SEQUENCE>1
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<TEXT>
Document 1 - file: d519919ddefa14a.htm

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<TEXT>
Document 2 - file: g519919logo.jpg

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<SEQUENCE>3
<FILENAME>g519919n2.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 3 - file: g519919n2.jpg

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<TEXT>
Document 4 - file: g519919naa1.jpg

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<FILENAME>g519919naa2.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 5 - file: g519919naa2.jpg

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<SEQUENCE>6
<FILENAME>g519919naa3.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 6 - file: g519919naa3.jpg

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<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>7
<FILENAME>g519919naa4.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 7 - file: g519919naa4.jpg

</DOCUMENT>
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