<SEC-DOCUMENT>0001127602-21-006281.txt : 20210217
<SEC-HEADER>0001127602-21-006281.hdr.sgml : 20210217
<ACCEPTANCE-DATETIME>20210217170306
ACCESSION NUMBER:		0001127602-21-006281
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210212
FILED AS OF DATE:		20210217
DATE AS OF CHANGE:		20210217

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Vounatsos Michel
		CENTRAL INDEX KEY:			0001672709

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19311
		FILM NUMBER:		21645867

	MAIL ADDRESS:	
		STREET 1:		BIOGEN INC.
		STREET 2:		225 BINNEY ST.
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

ISSUER:		

	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

	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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            <rptOwnerStreet2>225 BINNEY ST.</rptOwnerStreet2>
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            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02142</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isOfficer>1</isOfficer>
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    <footnotes>
        <footnote id="F1">Represents shares withheld to satisfy the withholding tax liability due upon the vesting of shares, as previously disclosed by reporting person on January 29, 2021.</footnote>
        <footnote id="F2">The number of RSUs reported represents the maximum possible number of shares that are eligible for vesting, which is 200% of the number of shares at target payout. One-third of these RSUs are eligible to vest on each of the first three anniversaries of the grant date. The actual number of shares that will vest on each vesting date will be determined by comparing the price of Biogen common stock on such vesting date to the price on the grant date (i.e., number of vested shares = number of shares at target payout times [the 30-day average closing stock price ending on the vesting date divided by the 30-day average closing stock price following and including the grant date]).</footnote>
        <footnote id="F3">This represents the difference between the maximum possible number of shares that were eligible for vesting and the actual number that vested.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Suzanne Murray, Attorney in Fact for Michel Vounatsos</signatureName>
        <signatureDate>2021-02-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
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</SEC-DOCUMENT>
