<SEC-DOCUMENT>0001193125-21-006295.txt : 20210111
<SEC-HEADER>0001193125-21-006295.hdr.sgml : 20210111
<ACCEPTANCE-DATETIME>20210111161958
ACCESSION NUMBER:		0001193125-21-006295
CONFORMED SUBMISSION TYPE:	SC 13G
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20210111
DATE AS OF CHANGE:		20210111
GROUP MEMBERS:		BIOGEN MA INC.

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Sage Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001597553
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-88275
		FILM NUMBER:		21521009

	BUSINESS ADDRESS:	
		STREET 1:		215 FIRST STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		617-299-8380

	MAIL ADDRESS:	
		STREET 1:		215 FIRST STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

FILED BY:		

	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:		SC 13G

	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>SC 13G
<SEQUENCE>1
<FILENAME>d73181dsc13g.htm
<DESCRIPTION>SC 13G
<TEXT>
<HTML><HEAD>
<TITLE>SC 13G</TITLE>
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>WASHINGTON, D.C. 20549 </B></P> <P STYLE="font-size:18pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SCHEDULE 13G
</B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>UNDER THE SECURITIES EXCHANGE ACT OF 1934 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>(Amendment No.__) </B></P> <P STYLE="font-size:18pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:22pt; font-family:Times New Roman" ALIGN="center"><B>Sage
Therapeutics, Inc. </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(Name of Issuer) </B></P>
<P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Common Stock </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Title of
Class&nbsp;of Securities) </B></P> <P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>78667J108 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(CUSIP Number) </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>December&nbsp;31, 2020 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Date of Event Which Requires Filing of this Statement) </B></P> <P STYLE="font-size:18pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:18pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Check the
appropriate box to designate the rule pursuant to which this Schedule is filed: </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; margin-left:2%; text-indent:2%; font-size:10pt; font-family:Times New Roman">&#9744; Rule <FONT
STYLE="white-space:nowrap">13d-1(b)</FONT> </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">&#9746; Rule <FONT STYLE="white-space:nowrap">13d-1(c)</FONT> </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">&#9744; Rule <FONT STYLE="white-space:nowrap">13d-1(d)</FONT> </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">*</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">The remainder of this cover page shall be filled out for a reporting person&#146;s initial filing on this form
with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page. </P></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The information required on the remainder of this cover page shall not be deemed to be &#147;filed&#148; for the purpose of Section&nbsp;18 of the Securities
Exchange Act of 1934 (&#147;Act&#148;) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, <I>see</I> the <I>Notes</I>) </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
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<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>&nbsp;&nbsp;1&nbsp;</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-TOP:1px solid #000000; BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">NAME OF
REPORTING PERSON: I.R.S. IDENTIFICATION NO. OF ABOVE PERSON</P> <P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">Biogen Inc.
33-0112644</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><B>&nbsp;&nbsp;2</B></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">CHECK THE APPROPRIATE BOX IF A MEMBER
OF A GROUP</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(a)&nbsp;&nbsp;&#9744;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&#9744;</P>
<P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:1pt">&nbsp;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>&nbsp;&nbsp;3</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">SEC USE ONLY</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:1pt">&nbsp;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>&nbsp;&nbsp;4</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">CITIZENSHIP OR PLACE OF
ORGANIZATION</P> <P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">Delaware</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="middle" COLSPAN="3" ROWSPAN="4" ALIGN="center" STYLE="BORDER-LEFT:1px solid #000000; padding-left:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">NUMBER&nbsp;OF</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">SHARES</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">BENEFICIALLY</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">OWNED&nbsp;BY</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">EACH</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">REPORTING</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">PERSON</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">WITH</P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT STYLE="font-size:10pt"><B>5&nbsp;</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">SOLE VOTING POWER</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:1pt">&nbsp;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT STYLE="font-size:10pt"><B>6</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">SHARED VOTING POWER</P>
<P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">6,241,473 shares</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT STYLE="font-size:10pt"><B>7</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">SOLE DISPOSITIVE POWER</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:1pt">&nbsp;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><FONT STYLE="font-size:10pt"><B>8</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">SHARED DISPOSITIVE POWER</P>
<P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">6,241,473 shares</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>&nbsp;&nbsp;9</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-TOP:1px solid #000000; BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt">
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON</P> <P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">6,241,473 shares</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>10</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">CHECK IF THE AGGREGATE AMOUNT IN ROW
(9) EXCLUDES CERTAIN SHARES</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">&#9744;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>11</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">PERCENT OF CLASS REPRESENTED BY AMOUNT
IN ROW (9)</P> <P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">10.7%</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>12</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">TYPE OF REPORTING PERSON</P>
<P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">CO</P></TD></TR>
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<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>&nbsp;&nbsp;1&nbsp;</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-TOP:1px solid #000000; BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">NAME OF
REPORTING PERSON: I.R.S. IDENTIFICATION NO. OF ABOVE PERSON</P> <P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">Biogen MA Inc.
04-3002117</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><B>&nbsp;&nbsp;2</B></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">CHECK THE APPROPRIATE BOX IF A MEMBER
OF A GROUP</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(a)&nbsp;&nbsp;&#9744;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&#9744;</P>
<P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:1pt">&nbsp;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>&nbsp;&nbsp;3</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">SEC USE ONLY</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:1pt">&nbsp;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>&nbsp;&nbsp;4</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">CITIZENSHIP OR PLACE OF
ORGANIZATION</P> <P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">Massachusetts</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="middle" COLSPAN="3" ROWSPAN="4" ALIGN="center" STYLE="BORDER-LEFT:1px solid #000000; padding-left:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">NUMBER&nbsp;OF</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">SHARES</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">BENEFICIALLY</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">OWNED&nbsp;BY</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">EACH</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">REPORTING</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">PERSON</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">WITH</P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT STYLE="font-size:10pt"><B>5&nbsp;</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">SOLE VOTING POWER</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:1pt">&nbsp;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT STYLE="font-size:10pt"><B>6</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">SHARED VOTING POWER</P>
<P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">6,241,473 shares</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT STYLE="font-size:10pt"><B>7</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">SOLE DISPOSITIVE POWER</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:1pt">&nbsp;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><FONT STYLE="font-size:10pt"><B>8</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">SHARED DISPOSITIVE POWER</P>
<P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">6,241,473 shares</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>&nbsp;&nbsp;9</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-TOP:1px solid #000000; BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt">
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON</P> <P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">6,241,473 shares</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>10</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">CHECK IF THE AGGREGATE AMOUNT IN ROW
(9) EXCLUDES CERTAIN SHARES</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">&#9744;</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>11</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">PERCENT OF CLASS REPRESENTED BY AMOUNT
IN ROW (9)</P> <P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">10.7%</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:12pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt"><FONT STYLE="font-size:10pt"><B>12</B></FONT></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="5" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">TYPE OF REPORTING PERSON</P>
<P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:12pt; font-family:Times New Roman">CO</P></TD></TR>
</TABLE>
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;1(a). Name of Issuer: </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Sage Therapeutics, Inc. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;1(b).
Address of Issuer&#146;s Principal Executive Offices: </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The principal business address of Sage Therapeutics, Inc. is 215 First Street,
Cambridge, MA 02142. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;2(a). Name of Person Filing: </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">This statement is being filed on behalf of Biogen Inc. and Biogen MA Inc. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;2(b). Address of Principal Business Office or, if None, Residence: </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The principal business office of Biogen Inc. and Biogen MA Inc. is 225 Binney Street, Cambridge, Massachusetts 02142. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;2(c). Citizenship: </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Biogen Inc.
is a corporation organized under the laws of the State of Delaware. Biogen MA Inc. is a corporation organized under the laws of the Commonwealth of Massachusetts. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;2(d). Title of Class&nbsp;of Securities: </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Common Stock </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;2(e). CUSIP Number:
</B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">78667J108 </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;3. If this
statement is filed pursuant to &#167;&#167; <FONT STYLE="white-space:nowrap">240.13d-1(b),</FONT> or &#167;&#167; <FONT STYLE="white-space:nowrap">240.13d-2(b)</FONT> or (c), check whether the person filing is a: </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(a) [ ] Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o); </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(b) [ ] Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c); </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(c) [ ] Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c); </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(d) [ ] Investment company registered under Section&nbsp;8 of the Investment Company Act of 1940 (15 U.S.C. <FONT STYLE="white-space:nowrap">80a-8);</FONT>
</P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(e) [ ] An investment adviser in accordance with &#167; <FONT STYLE="white-space:nowrap">240.13d-1(b)(1)(ii)(E);</FONT> </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(f) [ ] An employee benefit plan or endowment fund in accordance with &#167; 240.13d 1(b)(1)(ii)(F); </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(g) [ ] A parent holding company or control person in accordance with &#167; <FONT STYLE="white-space:nowrap">240.13d-1(b)(1)(ii)(G);</FONT> </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(h) [ ] A savings association as defined in Section&nbsp;3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813); </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(i) [ ] A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act (15 U.S.C. <FONT
STYLE="white-space:nowrap">80a-3);</FONT> </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(j) [ ] A <FONT STYLE="white-space:nowrap">non-U.S.</FONT> institution in accordance with &#167; <FONT
STYLE="white-space:nowrap">240.13d-1(b)(1)(ii)(J);</FONT> </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(k) [ ] Group, in accordance with
<FONT STYLE="white-space:nowrap">&#167;240.13d-1(b)(1)(ii)(K).</FONT> </P>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">If filing as a <FONT STYLE="white-space:nowrap">non-U.S.</FONT> institution in accordance with &#167; <FONT
STYLE="white-space:nowrap">240.13d-1(b)(1)(ii)(J),</FONT> please specify the type of institution: </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;4. Ownership. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">4(a) <B>Amount beneficially owned:</B> </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">6,241,473
</P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">4(b) <B>Percent of Class:</B> </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">10.7%, as
calculated based on the number of shares of common stock outstanding as of October&nbsp;29, 2020, disclosed in Sage Therapeutics, Inc.&#146;s most recent quarterly report on Form <FONT STYLE="white-space:nowrap">10-Q</FONT> filed November&nbsp;5,
2020, plus the shares issued to Biogen as part of this transaction. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">4(c) <B>Number of shares as to which such person has</B>: </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(i) Sole power to vote or to direct the vote: 0 </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(ii) Shared power to vote or to direct the vote: 6,241,473 shares </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(iii) Sole power to dispose or to direct the disposition of: 0 </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(iv) Shared power to dispose or to direct the disposition of: 6,241,473 shares </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;5. Ownership of Five Percent or Less of a Class. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of
more than five percent of the class of securities, check the following [ ]. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;6. Ownership of More Than Five Percent on behalf of another
person. </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Not applicable. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;7. Identification and Classification of the Subsidiary Which Acquired the Security Being reported on by the Parent Holding Company. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Not applicable. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;8. Identification
and Classification of Members of the Group. </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Not applicable. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;9. Notice of Dissolution of Group. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Not applicable. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;10.
Certifications. </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not
acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that
purpose or effect, other than activities solely in connection with a nomination under &#167; <FONT STYLE="white-space:nowrap">240.14a-11.</FONT> </P>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SIGNATURE </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true,
complete and correct. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">BIOGEN INC. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">By:</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Michael Dambach</TD></TR>
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<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Name: Michael Dambach</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Title: &nbsp;&nbsp;Vice President and Treasurer</TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">BIOGEN MA INC. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">By:</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Michael Dambach</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Name: Michael Dambach</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Title: &nbsp;&nbsp;Vice President and Treasurer</TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Date: January&nbsp;11, 2021 </P>
</DIV></Center>


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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B><U>Exhibit A </U></B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>JOINT FILING AGREEMENT </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">In accordance with Rule <FONT STYLE="white-space:nowrap">13d-1(k)</FONT> under the Securities Exchange Act of 1934, as amended, each of the
persons named below agrees to the joint filing of a Statement on Schedule 13G (including amendments thereto) with respect to the common stock, $0.0001 par value per share, of Sage Therapeutics, Inc., a Delaware corporation, and further agrees that
this Joint Filing Agreement be included as an exhibit to such filings provided that, as contemplated by <FONT STYLE="white-space:nowrap">Section&nbsp;13d-1(k)(1)(ii),</FONT> no person shall be responsible for the completeness or accuracy of the
information concerning the other persons making the filing, unless such person knows or has reason to believe that such information is inaccurate. This Joint Filing Agreement may be executed in any number of counterparts, all of which together shall
constitute one and the same instrument. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Dated as of January&nbsp;11, 2021 </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


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<TD WIDTH="7%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">BIOGEN INC.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">By:</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Michael Dambach</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Name: Michael Dambach</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Title: &nbsp;&nbsp;Vice President and Treasurer</TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="7%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">BIOGEN MA INC.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">By:</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Michael Dambach</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Name: Michael Dambach</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Title: &nbsp;&nbsp;Vice President and Treasurer</TD></TR>
</TABLE>
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