<SEC-DOCUMENT>0001193125-24-118405-index.html : 20240426
<SEC-HEADER>0001193125-24-118405.hdr.sgml : 20240426
<ACCEPTANCE-DATETIME>20240426171504
ACCESSION NUMBER:		0001193125-24-118405
CONFORMED SUBMISSION TYPE:	ARS
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20231231
FILED AS OF DATE:		20240426
DATE AS OF CHANGE:		20240426
EFFECTIVENESS DATE:		20240426

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BIOGEN INC.
		CENTRAL INDEX KEY:			0000875045
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		ORGANIZATION NAME:           	03 Life Sciences
		IRS NUMBER:				330112644
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		ARS
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19311
		FILM NUMBER:		24885246

	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>
<DOCUMENT>
<TYPE>ARS
<SEQUENCE>1
<FILENAME>d803137dars.pdf
<DESCRIPTION>ARS
<TEXT>
Document 1 - file: d803137dars.pdf

</DOCUMENT>
</SEC-DOCUMENT>