<SEC-DOCUMENT>0001193125-16-643599.txt : 20160707
<SEC-HEADER>0001193125-16-643599.hdr.sgml : 20160707
<ACCEPTANCE-DATETIME>20160707173004
ACCESSION NUMBER:		0001193125-16-643599
CONFORMED SUBMISSION TYPE:	SC 13D
PUBLIC DOCUMENT COUNT:		2
FILED AS OF DATE:		20160707
DATE AS OF CHANGE:		20160707
GROUP MEMBERS:		AMIR NASHAT
GROUP MEMBERS:		JONATHAN A. FLINT
GROUP MEMBERS:		POLARIS VENTURE MANAGEMENT CO. V, L.L.C
GROUP MEMBERS:		POLARIS VENTURE PARTNERS ENTREPRENEURS' FUND V, L.P.
GROUP MEMBERS:		POLARIS VENTURE PARTNERS FOUNDERS' FUND V, L.P.
GROUP MEMBERS:		POLARIS VENTURE PARTNERS SPECIAL FOUNDERS' FUND V, L.P.
GROUP MEMBERS:		TERRANCE G. MCGUIRE

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SELECTA BIOSCIENCES INC
		CENTRAL INDEX KEY:			0001453687
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13D
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-89550
		FILM NUMBER:		161757310

	BUSINESS ADDRESS:	
		STREET 1:		480 ARSENAL STREET
		STREET 2:		BUILDING ONE
		CITY:			WATERTOWN
		STATE:			MA
		ZIP:			02472
		BUSINESS PHONE:		617-923-1400

	MAIL ADDRESS:	
		STREET 1:		480 ARSENAL STREET
		STREET 2:		BUILDING ONE
		CITY:			WATERTOWN
		STATE:			MA
		ZIP:			02472

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Polaris Venture Partners V, L.P.
		CENTRAL INDEX KEY:			0001439590
		IRS NUMBER:				204234825
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13D

	BUSINESS ADDRESS:	
		STREET 1:		1000 WINTER STREET
		STREET 2:		SUITE 3350
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
		BUSINESS PHONE:		781-290-0770

	MAIL ADDRESS:	
		STREET 1:		1000 WINTER STREET
		STREET 2:		SUITE 3350
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13D
<SEQUENCE>1
<FILENAME>d226416dsc13d.htm
<DESCRIPTION>SC 13D
<TEXT>
<HTML><HEAD>
<TITLE>SC 13D</TITLE>
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 <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 13D
</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.&nbsp;&nbsp;&nbsp;&nbsp; )* </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>SELECTA
BIOSCIENCES,&nbsp;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, $0.0001 par value </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Title of Class of Securities) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>816212104 </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="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Polaris Partners</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>One Marina Park Drive, 10<SUP STYLE="font-size:85%; vertical-align:top">th</SUP> Floor</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Boston, MA 02210</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Gunderson Dettmer Stough Villeneuve</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Franklin &amp; Hachigian, LLP</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>One Marina Park Drive, Suite 900</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Boston, MA 02210</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Attn:
Jay K. Hachigian, Esq.</B></P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(617) 648-9100</B></P></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>June&nbsp;27, 2016 </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; font-size:10pt; font-family:Times New Roman">If the filing person has
previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of &#167;&#167;240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box:&nbsp;&nbsp;<FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT> </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:2pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Note</B>: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See &#167;240.13d-7 for
other parties to whom copies are to be sent. </P> <P STYLE="font-size:4pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD ALIGN="left" VALIGN="top">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 disclosures provided in a prior cover page. </TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; 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, see the Notes). </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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<TD VALIGN="top">CUSIP No. 816212104</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right"> Page
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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">&nbsp;&nbsp;1.&nbsp;</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Names of
Reporting Persons.</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Polaris Venture Partners V, L.P. (&#147;PVP V&#148;)</P></TD></TR>

<TR STYLE="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">&nbsp;&nbsp;2.</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:8pt"> <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 (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(a)&nbsp;&nbsp;<FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;<FONT
STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;3.</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:8pt"> <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="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">&nbsp;&nbsp;4.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Source of Funds (See Instructions)</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">WC</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;5.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if Disclosure of Legal
Proceedings Is Required Pursuant to Items 2(d) or 2(e)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;6.</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:8pt"> <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:10pt; font-family:Times New Roman">Delaware</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="middle" COLSPAN="3" ROWSPAN="4" 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:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">With</P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:1pt" align="left">&nbsp;</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">&nbsp;&nbsp;7.&nbsp;</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">1,914,665 shares, of which (a) 1,836,703 shares are Common Stock and (b) 77,962 shares
represent underlying Common Stock pursuant to a warrant exercisable within 60 days, except that (i) Polaris Venture Management Co. V, L.L.C. (&#147;PVM V&#148;), the general partner of PVP V, may be deemed to have sole power to vote these shares,
and (ii) Jonathan A. Flint (&#147;Flint&#148;), a managing member of PVM V, may be deemed to have shared power to vote these shares, Terrance G. McGuire (&#147;McGuire&#148;), a managing member of PVM V, may be deemed to have shared power to vote
these shares and Amir Nashat (&#147;Nashat&#148;), an assignee of PVM V and member of the Board of Directors of the Issuer, may be deemed to have shared power to vote these shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;8.</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:8pt"> <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:10pt; font-family:Times New Roman">See response to row 7.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;9.</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">1,914,665 shares, of which (a) 1,836,703 shares are Common Stock and (b) 77,962 shares
represent underlying Common Stock pursuant to a warrant exercisable within 60 days, except that (i) PVM V, the general partner of PVP V, may be deemed to have sole power to dispose of these shares, and (ii) Flint, a managing member of PVM V, may be
deemed to have shared power to dispose of these shares, McGuire, a managing member of PVM V, may be deemed to have shared power to dispose of these shares and Nashat, an assignee of PVM V and member of the Board of Directors of the Issuer, maybe be
deemed to have shared power to dispose of these shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top">10.</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; padding-right:8pt"> <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:10pt; font-family:Times New Roman">See response to row 9.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">11.</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:8pt">
<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:10pt; font-family:Times New Roman">1,914,665</P></TD></TR>
<TR STYLE="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">12.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if the Aggregate Amount in Row
(11)&nbsp;Excludes Certain Shares (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">13.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Percent of Class Represented by Amount
in Row (11)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">10.7%</P></TD></TR>
<TR STYLE="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">14.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Type of Reporting Person (See
Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">PN</P></TD></TR>
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<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">CUSIP No. 816212104</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right"> Page
 3
 of 16</TD></TR></TABLE> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>

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<TD WIDTH="3%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="5%"></TD>
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<TD WIDTH="87%"></TD></TR>


<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">&nbsp;&nbsp;1.&nbsp;</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Names of
Reporting Persons.</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Polaris Venture Partners Entrepreneurs&#146; Fund V, L.P.
(&#147;PVPE V&#148;)</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;2.</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:8pt"> <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 (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(a)&nbsp;&nbsp;<FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;<FONT
STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;3.</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:8pt"> <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="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">&nbsp;&nbsp;4.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Source of Funds (See Instructions)</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">WC</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;5.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;6.</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:8pt"> <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:10pt; font-family:Times New Roman">Delaware</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="middle" COLSPAN="3" ROWSPAN="4" 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:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">With</P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:1pt" align="left">&nbsp;</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">&nbsp;&nbsp;7.&nbsp;</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">37,312 shares, of which (a) 35,793 shares are Common Stock and (b) 1,519 shares represent
underlying Common Stock pursuant to a warrant exercisable within 60 days, except that (i) PVM V, the general partner of PVPE V, may be deemed to have sole power to vote these shares, and (ii) Flint, a managing member of PVM V, may be deemed to have
shared power to vote these shares, McGuire, a managing member of PVM V, may be deemed to have shared power to vote these shares and Nashat, an assignee of PVM V and member of the Board of Directors of the Issuer, may be deemed to have shared power
to vote these shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;8.</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:8pt"> <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:10pt; font-family:Times New Roman">See response to row 7.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;9.</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">37,312 shares, of which (a) 35,793 shares are Common Stock and (b) 1,519 shares represent
underlying Common Stock pursuant to a warrant exercisable within 60 days, except that (i) PVM V, the general partner of PVPE V, may be deemed to have sole power to dispose of these shares, and (ii) Flint, a managing member of PVM V, may be deemed to
have shared power to dispose of these shares, McGuire, a managing member of PVM V, may be deemed to have shared power to dispose of these shares, and Nashat, an assignee of PVM V and member of the Board of Directors of the Issuer, may be deemed to
have shared power to dispose of these shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top">10.</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; padding-right:8pt"> <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:10pt; font-family:Times New Roman">See response to Row 9.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">11.</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:8pt">
<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:10pt; font-family:Times New Roman">37,312</P></TD></TR>
<TR STYLE="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">12.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if the Aggregate Amount in Row
(11)&nbsp;Excludes Certain Shares (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">13.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Percent of Class Represented by Amount
in Row (11)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">0.2%</P></TD></TR>
<TR STYLE="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">14.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Type of Reporting Person (See
Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">PN</P></TD></TR>
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<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="47%"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">CUSIP No. 816212104</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right"> Page
 4
 of 16</TD></TR></TABLE> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>

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<TD WIDTH="3%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="5%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="2%"></TD>
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<TD WIDTH="87%"></TD></TR>


<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">&nbsp;&nbsp;1.&nbsp;</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Names of
Reporting Persons.</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Polaris Venture Partners Founders&#146; Fund V, L.P. (&#147;PVPFF
V&#148;)</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;2.</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:8pt"> <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 (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(a)&nbsp;&nbsp;<FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;<FONT
STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;3.</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:8pt"> <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="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">&nbsp;&nbsp;4.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Source of Funds (See Instructions)</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">WC</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;5.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;6.</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:8pt"> <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:10pt; font-family:Times New Roman">Delaware</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="middle" COLSPAN="3" ROWSPAN="4" 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:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">With</P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:1pt" align="left">&nbsp;</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">&nbsp;&nbsp;7.&nbsp;</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">13,111 shares, of which (a) 12,577 shares are Common Stock and (b) 534 shares represent
underlying Common Stock pursuant to a warrant exercisable within 60 days, except that (i) PVM V, the general partner of PVPFF V, may be deemed to have sole power to vote these shares, and (ii) Flint, a managing member of PVM V, may be deemed to have
shared power to vote these shares, McGuire, a managing member of PVM V, may be deemed to have shared power to vote these shares, and Nashat, an assignee of PVM V and member of the Board of Directors of the Issuer, may be deemed to have shared power
to vote these shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;8.</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:8pt"> <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:10pt; font-family:Times New Roman">See response to row 7.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;9.</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">13,111 shares, of which (a) 12,577 shares are Common Stock and (b) 534 shares represent
underlying Common Stock pursuant to a warrant exercisable within 60 days, except that (i) PVM V, the general partner of PVPFF V, may be deemed to have sole power to dispose of these shares, and (ii) Flint, a managing member of PVM V, may be deemed
to have shared power to dispose of these shares, McGuire, a managing member of PVM V, may be deemed to have shared power to dispose of these shares, and Nashat, an assignee of PVM V and member of the Board of Directors of the Issuer, may be deemed
to have shared power to dispose of these shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top">10.</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; padding-right:8pt"> <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:10pt; font-family:Times New Roman">See response to Row 9.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">11.</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:8pt">
<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:10pt; font-family:Times New Roman">13,111</P></TD></TR>
<TR STYLE="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">12.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if the Aggregate Amount in Row
(11)&nbsp;Excludes Certain Shares (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">13.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Percent of Class Represented by Amount
in Row (11)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">0.1%</P></TD></TR>
<TR STYLE="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">14.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Type of Reporting Person (See
Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">PN</P></TD></TR>
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<TD VALIGN="top">CUSIP No. 816212104</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right"> Page
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<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">&nbsp;&nbsp;1.&nbsp;</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Names of
Reporting Persons.</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Polaris Venture Partners Special Founders&#146; Fund V, L.P.
(&#147;PVPSFF V&#148;)</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;2.</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:8pt"> <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 (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(a)&nbsp;&nbsp;<FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;<FONT
STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;3.</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:8pt"> <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="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">&nbsp;&nbsp;4.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Source of Funds (See Instructions)</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">WC</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;5.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;6.</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:8pt"> <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:10pt; font-family:Times New Roman">Delaware</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="middle" COLSPAN="3" ROWSPAN="4" 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:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">With</P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:1pt" align="left">&nbsp;</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">&nbsp;&nbsp;7.&nbsp;</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">22,380 shares, of which (a) 18,364 shares are Common Stock and (b) 4,016 shares represent
underlying Common Stock pursuant to a warrant exercisable within 60 days, except that (i) PVM V, the general partner of PVPSFF V, may be deemed to have sole power to vote these shares, and (ii) Flint, a managing member of PVM V, may be deemed to
have shared power to vote these shares, McGuire, a managing member of PVM V, may be deemed to have shared power to vote these shares, and Nashat, an assignee of PVM V and member of the Board of Directors of the Issuer, may be deemed to have shared
power to vote these shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;8.</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:8pt"> <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:10pt; font-family:Times New Roman">See response to row 7.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;9.</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">22,380 shares, of which (a) 18,364 shares are Common Stock and (b) 4,016 shares represent
underlying Common Stock pursuant to a warrant exercisable within 60 days, except that (i) PVM V, the general partner of PVPSFF V, may be deemed to have sole power to dispose of these shares, and (ii) Flint, a managing member of PVM V, may be deemed
to have shared power to dispose of these shares, McGuire, a managing member of PVM V, may be deemed to have shared power to dispose of these shares, and Nashat, an assignee of PVM V and member of the Board of Directors of the Issuer, may be deemed
to have shared power to dispose of these shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top">10.</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; padding-right:8pt"> <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:10pt; font-family:Times New Roman">See response to row 9.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">11.</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:8pt">
<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:10pt; font-family:Times New Roman">22,380</P></TD></TR>
<TR STYLE="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">12.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if the Aggregate Amount in Row
(11)&nbsp;Excludes Certain Shares (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">13.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Percent of Class Represented by Amount
in Row (11)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">0.1%</P></TD></TR>
<TR STYLE="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">14.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Type of Reporting Person (See
Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">PN</P></TD></TR>
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<TD VALIGN="top">CUSIP No. 816212104</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right"> Page
 6
 of 16</TD></TR></TABLE> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>

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<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">&nbsp;&nbsp;1.&nbsp;</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Names of
Reporting Persons.</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Polaris Venture Management Co. V, L.L.C. (&#147;PVM
V&#148;)</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;2.</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:8pt"> <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 (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(a)&nbsp;&nbsp;<FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;<FONT
STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;3.</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:8pt"> <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="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">&nbsp;&nbsp;4.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Source of Funds (See Instructions)</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">AF</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;5.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;6.</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:8pt"> <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:10pt; font-family:Times New Roman">Delaware</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="middle" COLSPAN="3" ROWSPAN="4" 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:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">With</P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:1pt" align="left">&nbsp;</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">&nbsp;&nbsp;7.&nbsp;</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">1,987,468 shares, of which (a) 1,836,703 shares are directly owned by PVP V, (b) 77,962
shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVP V, (c) 35,793 shares are directly owned by PVPE V, (d) 1,519 shares represent underlying Common Stock pursuant to a warrant exercisable within 60
days issued to PVPE V, (e) 12,577 shares are directly owned by PVPFF V, (g) 534 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPFF V, (h) 18,364 shares are directly owned by PVPSFF V and (i)
4,016 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPSFF V, except that Flint, a managing member of PVM V, as the general partner of each of PVP V, PVPE V, PVPFF V and PVPSFF V, may be deemed
to have shared power to vote these shares, McGuire, a managing member of PVM V, may be deemed to have shared power to vote these shares, and Nashat, an assignee of PVM V and member of the Board of Directors of the Issuer, may be deemed to have
shared power to vote these shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;8.</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:8pt"> <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:10pt; font-family:Times New Roman">See response to row 7.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;9.</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">1,987,468 shares, of which (a) 1,836,703 shares are directly owned by PVP V, (b) 77,962
shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVP V, (c) 35,793 shares are directly owned by PVPE V, (d) 1,519 shares represent underlying Common Stock pursuant to a warrant exercisable within 60
days issued to PVPE V, (e) 12,577 shares are directly owned by PVPFF V, (g) 534 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPFF V, (h) 18,364 shares are directly owned by PVPSFF V and (i)
4,016 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPSFF V, except that Flint, a managing member of PVM V, as the general partner of each of PVP V, PVPE V, PVPFF V and PVPSFF V, may be deemed
to have shared power to dispose of these shares, McGuire, a managing member of PVM V, may be deemed to have shared power to dispose of these shares, and Nashat, an assignee of PVM V and member of the Board of Directors of the Issuer, may be deemed
to have shared power to dispose of these shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top">10.</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; padding-right:8pt"> <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:10pt; font-family:Times New Roman">See response to row 9.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">11.</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:8pt">
<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:10pt; font-family:Times New Roman">1,987,468</P></TD></TR>
<TR STYLE="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">12.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if the Aggregate Amount in Row
(11)&nbsp;Excludes Certain Shares (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">13.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Percent of Class Represented by Amount
in Row (11)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">11.1%</P></TD></TR>
<TR STYLE="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">14.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Type of Reporting Person (See
Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">OO</P></TD></TR>
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<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="47%"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">CUSIP No. 816212104</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right"> Page
 7
 of 16</TD></TR></TABLE> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>

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<TD WIDTH="5%"></TD>
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<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">&nbsp;&nbsp;1.&nbsp;</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Names of
Reporting Persons.</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Jonathan A. Flint</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;2.</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:8pt"> <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 (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(a)&nbsp;&nbsp;<FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;<FONT
STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;3.</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:8pt"> <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="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">&nbsp;&nbsp;4.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Source of Funds (See Instructions)</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">AF</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;5.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;6.</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:8pt"> <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:10pt; font-family:Times New Roman">USA</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="middle" COLSPAN="3" ROWSPAN="4" 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:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">With</P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:1pt" align="left">&nbsp;</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">&nbsp;&nbsp;7.&nbsp;</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">1,987,468 shares, of which (a) 1,836,703 shares are directly owned by PVP V, (b) 77,962
shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVP V, (c) 35,793 shares are directly owned by PVPE V, (d) 1,519 shares represent underlying Common Stock pursuant to a warrant exercisable within 60
days issued to PVPE V, (e) 12,577 shares are directly owned by PVPFF V, (g) 534 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPFF V, (h) 18,364 shares are directly owned by PVPSFF V and (i)
4,016 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPSFF V, except that PVM V, as the general partner of PVP V, PVPE V, PVPFF V and PVPSFF V, may be deemed to have sole power to vote PVP
V&#146;s, PVPE V&#146;s, PVPFF V&#146;s and PVPSFF V&#146;s shares (collectively, the &#147;Fund V Shares&#148;), McGuire, as a managing member of PVM V, may be deemed to have shared power to vote the Fund V Shares, and Nashat, an assignee of PVM V,
may be deemed to have shared power to vote the Fund V Shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;8.</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:8pt"> <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:10pt; font-family:Times New Roman">See response to row 7.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;9.</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">1,987,468 shares, of which (a) 1,836,703 shares are directly owned by PVP V, (b) 77,962
shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVP V, (c) 35,793 shares are directly owned by PVPE V, (d) 1,519 shares represent underlying Common Stock pursuant to a warrant exercisable within 60
days issued to PVPE V, (e) 12,577 shares are directly owned by PVPFF V, (g) 534 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPFF V, (h) 18,364 shares are directly owned by PVPSFF V and (i)
4,016 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPSFF V, except that PVM V, as general partner of PVP V, PVPE V, PVPFF V and PVPSFF V, maybe deemed to have sole power to dispose of the Fund
V Shares, McGuire, as a managing member of PVM V, may be deemed to have shared power to dispose of the Fund V Shares, and Nashat, an assignee of PVM V, may be deemed to have shared power to dispose of the Fund V Shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top">10.</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; padding-right:8pt"> <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:10pt; font-family:Times New Roman">See response to row 9.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">11.</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:8pt">
<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:10pt; font-family:Times New Roman">1,987,468</P></TD></TR>
<TR STYLE="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">12.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if the Aggregate Amount in Row
(11)&nbsp;Excludes Certain Shares (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">13.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Percent of Class Represented by Amount
in Row (11)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">11.1%</P></TD></TR>
<TR STYLE="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">14.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Type of Reporting Person (See
Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">IN</P></TD></TR>
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<TD VALIGN="top">CUSIP No. 816212104</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right"> Page
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 of 16</TD></TR></TABLE> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>

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<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">&nbsp;&nbsp;1.&nbsp;</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Names of
Reporting Persons.</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Terrance G. McGuire</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;2.</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:8pt"> <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 (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(a)&nbsp;&nbsp;<FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;<FONT
STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;3.</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:8pt"> <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="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">&nbsp;&nbsp;4.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Source of Funds (See Instructions)</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">AF</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;5.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;6.</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:8pt"> <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:10pt; font-family:Times New Roman">USA</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="middle" COLSPAN="3" ROWSPAN="4" 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:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">With</P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:1pt" align="left">&nbsp;</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">&nbsp;&nbsp;7.&nbsp;</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">1,987,468 shares, of which (a) 1,836,703 shares are directly owned by PVP V, (b) 77,962
shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVP V, (c) 35,793 shares are directly owned by PVPE V, (d) 1,519 shares represent underlying Common Stock pursuant to a warrant exercisable within 60
days issued to PVPE V, (e) 12,577 shares are directly owned by PVPFF V, (g) 534 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPFF V, (h) 18,364 shares are directly owned by PVPSFF V and (i)
4,016 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPSFF V, except that PVM V, as the general partner of PVP V, PVPE V, PVPFF V and PVPSFF V, may be deemed to have sole power to vote the Fund V
Shares, Flint, as a managing member of PVM V, may be deemed to have shared power to vote the Fund V Shares, and Nashat, an assignee of PVM V, may be deemed to have shared power to vote the Fund V Shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;8.</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:8pt"> <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:10pt; font-family:Times New Roman">See response to row 7.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;9.</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">1,987,468 shares, of which (a) 1,836,703 shares are directly owned by PVP V, (b) 77,962
shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVP V, (c) 35,793 shares are directly owned by PVPE V, (d) 1,519 shares represent underlying Common Stock pursuant to a warrant exercisable within 60
days issued to PVPE V, (e) 12,577 shares are directly owned by PVPFF V, (g) 534 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPFF V, (h) 18,364 shares are directly owned by PVPSFF V and (i)
4,016 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPSFF V, except that PVM V, as general partner of PVP V, PVPE V, PVPFF V and PVPSFF V, may be deemed to have sole power to dispose of the Fund
V Shares, Flint, as a managing member of PVM V, may be deemed to have shared power to dispose of the Fund V Shares, and Nashat, an assignee of PVM V, may be deemed to have shared power to dispose of the Fund V Shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top">10.</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; padding-right:8pt"> <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:10pt; font-family:Times New Roman">See response to row 9.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">11.</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:8pt">
<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:10pt; font-family:Times New Roman">1,987,468</P></TD></TR>
<TR STYLE="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">12.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if the Aggregate Amount in Row
(11)&nbsp;Excludes Certain Shares (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">13.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Percent of Class Represented by Amount
in Row (11)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">11.1%</P></TD></TR>
<TR STYLE="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">14.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Type of Reporting Person (See
Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">IN</P></TD></TR>
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<TD VALIGN="top">CUSIP No. 816212104</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right"> Page
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 of 16</TD></TR></TABLE> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>

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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">&nbsp;&nbsp;1.&nbsp;</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Names of
Reporting Persons.</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Amir Nashat</P></TD></TR>
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<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">&nbsp;&nbsp;2.</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:8pt"> <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 (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(a)&nbsp;&nbsp;<FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;<FONT
STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></P></TD></TR>
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<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">&nbsp;&nbsp;3.</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:8pt"> <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>
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<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">&nbsp;&nbsp;4.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Source of Funds (See Instructions)</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">AF</P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;5.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">&nbsp;&nbsp;6.</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:8pt"> <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:10pt; font-family:Times New Roman">USA</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="middle" COLSPAN="3" ROWSPAN="4" 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:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">With</P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:1pt" align="left">&nbsp;</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">&nbsp;&nbsp;7.&nbsp;</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">1,987,468 shares, of which (a) 1,836,703 shares are directly owned by PVP V, (b) 77,962
shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVP V, (c) 35,793 shares are directly owned by PVPE V, (d) 1,519 shares represent underlying Common Stock pursuant to a warrant exercisable within 60
days issued to PVPE V, (e) 12,577 shares are directly owned by PVPFF V, (g) 534 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPFF V, (h) 18,364 shares are directly owned by PVPSFF V and (i)
4,016 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPSFF V, except that PVM V, as the general partner of PVP V, PVPE V, PVPFF V and PVPSFF V, may be deemed to have sole power to vote the Fund V
Shares, Flint, as a managing member of PVM V, may be deemed to have shared power to vote the Fund V Shares, and McGuire, a managing member of PVM V, may be deemed to have shared power to vote the Fund V Shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;8.</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:8pt"> <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:10pt; font-family:Times New Roman">See response to row 7.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<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">&nbsp;&nbsp;9.</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:8pt"> <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:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">1,987,468 shares, of which (a) 1,836,703 shares are directly owned by PVP V, (b) 77,962
shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVP V, (c) 35,793 shares are directly owned by PVPE V, (d) 1,519 shares represent underlying Common Stock pursuant to a warrant exercisable within 60
days issued to PVPE V, (e) 12,577 shares are directly owned by PVPFF V, (g) 534 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPFF V, (h) 18,364 shares are directly owned by PVPSFF V and (i)
4,016 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPSFF V, except that PVM V, as general partner of PVP V, PVPE V, PVPFF V and PVPSFF V, may be deemed to have sole power to dispose of the Fund
V Shares, Flint, as a managing member of PVM V, may be deemed to have shared power to dispose of the Fund V Shares, and McGuire, a managing member of PVM V, may be deemed to have shared power to dispose of the Fund V Shares.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top">10.</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000">&nbsp;&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-RIGHT:1px solid #000000; padding-right:8pt"> <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:10pt; font-family:Times New Roman">See response to row 9.</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">11.</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:8pt">
<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:10pt; font-family:Times New Roman">1,987,468</P></TD></TR>
<TR STYLE="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">12.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Check if the Aggregate Amount in Row
(11)&nbsp;Excludes Certain Shares (See Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><FONT
STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></P></TD></TR>
<TR STYLE="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">13.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Percent of Class Represented by Amount
in Row (11)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">11.1%</P></TD></TR>
<TR STYLE="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">14.</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:8pt"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Type of Reporting Person (See
Instructions)</P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">IN</P></TD></TR>
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<TD VALIGN="top">CUSIP No. 816212104</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right"> Page
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 of 16</TD></TR></TABLE> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SCHEDULE 13D </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Item&nbsp;1. Security and Issuer. </U></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">This statement on
Schedule 13D relates to the Common Stock, $0.0001 par value per share (the &#147;Common Stock&#148;), of Selecta Bioscience, Inc. (the &#147;Issuer&#148;). The Issuer&#146;s principal executive office is located at 480 Arsenal Street, Building One,
Watertown, MA 02472 </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Item&nbsp;2. Identity and Background. </U></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(a) This Schedule 13D is being filed on behalf of each of the following persons pursuant to Rule 13d-1(k) of Regulation D-G under the Securities Exchange Act
of 1934, as amended (the &#147;Exchange Act&#148;): Polaris Venture Partners V, L.P. (&#147;PVP V&#148;), Polaris Venture Partners Entrepreneurs&#146; Fund V, L.P. (&#147;PVPE V&#148;), Polar Venture Partners Founders&#146; Fund V, L.P (&#147;PVPFF
V&#148;),Polaris Venture Partners Special Founders&#146; Fund, L.P. (&#147;PVPSFF V&#148;), Polaris Venture Management Co. V, L.L.C. (&#147;PVM V), Jonathan A. Flint (&#147;Flint&#148;), Terrance G. McGuire (&#147;McGuire&#148;) and Amir Nashat
(&#147;Nashat&#148;) (collectively, the &#147;Reporting Persons&#148;). The Reporting Persons are making this single, joint filing because they may be deemed to constitute a &#147;group&#148; within the meaning of Section&nbsp;13(d)(3) of the
Exchange Act. The agreement between the Reporting Persons to file as a group (the &#147;Joint Filing Agreement&#148;) is attached hereto as Exhibit A. </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(b)-(c)&nbsp;The principal business of each of PVP V, PVPE V, PVPFF V and PVPSFF V is that of a private investment partnership. The sole general partner of
each of PVP V, PVPE V, PVPFF VI and PVPSFF V is PVM V. The principal business of PVM V is that of a limited liability company acting as the general partner of each of PVP V, PVPE V, PVPFF VI and PVPSFF V. Flint and McGuire are the managing members
of PVM VI, and Nashat is a member of the Board of Directors of the Issuer and the holder of an assignee interest in PVM V. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The principal business address
of each of the entities and individuals named in this Item&nbsp;2 is c/o Polaris Partners, One Marina Park Drive, 10<SUP STYLE="font-size:85%; vertical-align:top">th</SUP> Floor, Boston, Massachusetts, 02210. </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(d)&#150;(e) During the last five years, none of the Reporting Persons or individuals named in this Item&nbsp;2 has (i)&nbsp;been convicted in any criminal
proceeding (excluding traffic violations or similar misdemeanors); or (ii)&nbsp;been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction resulting in his being subject to a judgment, decree or final order
enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws. </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD ALIGN="left" VALIGN="top">Each of the individuals named in this Item&nbsp;2 is a citizen of the United States. </TD></TR></TABLE> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Item&nbsp;3. Source
and Amount of Funds or Other Consideration. </U></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">On June&nbsp;21, 2016, the Registration Statement on Form S-1 filed with the Securities and Exchange
Commission by the Issuer (File No.&nbsp;333-211555) in connection with its initial public offering of 5,000,000 shares of Common Stock was declared effective. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">In a number of transactions, the Reporting Persons acquired 158,904 shares of Common Stock, shares of Series A Preferred Stock convertible into 345,315 shares
of Common Stock, shares Series B Preferred Stock convertible into 631,458 shares of Common Stock, shares Series C Preferred Stock convertible into 235,041 shares of Common Stock, shares Series D Preferred Stock convertible into 247,133 shares of
Common Stock, shares Series E Preferred Stock convertible into 253,748 shares of Common Stock and warrants to purchase an aggregate of 84,031 shares of Common Stock, collectively for an aggregate purchase price of $16,067,386.97 (collectively, the
&#147;Pre-IPO shares&#148;). The Pre-IPO shares converted into Common Stock, respectively, upon the closing of the offering. </P>

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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">On June&nbsp;27, 2016, the Reporting person acquired 150,000 shares of Common Stock for an aggregate purchase
price of $2,100,000 (the &#147;IPO shares&#148;). </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Reporting Persons obtained the amounts required for all purchases of Pre-IPO shares and IPO shares
from their working capital. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Item&nbsp;4. Purpose of Transaction. </U></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Nashat, as a director of the Issuer and by virtue of his assignee interest in PVM V, and each of Flint and McGuire, by virtue of their roles as the managing
members of PVM V, may each be deemed to hold certain voting powers with respect to the reportable securities owned by PVP V, PVPE V, PVPFF V, and PVPSFF V. Except as otherwise described in this statement, the Reporting Persons do not have any
present plans or proposals that relate to or would result in: (i)&nbsp;the acquisition by any person of additional securities of the Issuer, or the disposition of securities of the Issuer; (ii)&nbsp;an extraordinary corporate transaction, such as a
merger, reorganization or liquidation, involving the Issuer or any of its subsidiaries; (iii)&nbsp;a sale or transfer of a material amount of assets of the Issuer or any of its subsidiaries; (iv)&nbsp;any change in the present board of directors or
management of the Issuer, including any plans or proposals to change the number or term of directors or to fill any existing vacancies on the board; (v)&nbsp;any material change in the present capitalization or dividend policy of the Issuer;
(vi)&nbsp;any other material change in the Issuer&#146;s business or corporate structure; (vii)&nbsp;changes in the Issuer&#146;s charter, by-laws or instruments corresponding thereto or other actions which may impede the acquisition of control of
the Issuer by any person; (viii)&nbsp;causing a class of securities of the Issuer to be de-listed from a national securities exchange or to cease to be authorized to be quoted in an inter-dealer quotation system of a registered national securities
association; (ix)&nbsp;a class of equity securities of the Issuer becoming eligible for termination of registration pursuant to Section&nbsp;12(g)(4) of the Exchange Act; or (x)&nbsp;any action similar to any of those enumerated above. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Item&nbsp;5. Interest in Securities of the Issuer. </U></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The
information below is based on a total of 17,899,586 shares of Common Stock outstanding as reported on the Issuer&#146;s Prospectus filed with the SEC on June&nbsp;23, 2016. </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(a) PVP V beneficially owns 1,914,665 shares of Common Stock, or approximately 10.7% of the Common Stock outstanding, of which 1,836,703 shares are directly
owned by PVP V and 77,962 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVP V. PVPE V beneficially owns 37,312 shares of Common Stock, or approximately 0.2% of the Common Stock outstanding, of
which 35,793 shares are directly owned by PVPE V and 1,519 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPE V. PVPFF V beneficially owns 13,111 shares of Common Stock, or approximately 0.1% of
the Common Stock outstanding, of which 12,577 shares are directly owned by PVPFF V and 534 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPFF V. PVPSFF V beneficially owns 22,380 shares of
Common Stock, or approximately 0.1% of the Common Stock outstanding, of which 18,364 shares are directly owned by PVPSFF V and 4,016 shares represent underlying Common Stock pursuant to a warrant exercisable within 60 days issued to PVPSFF V. PVM V,
as the general partner of PVP V, PVPE V, PVPFF V and PVPSFF V, may be deemed to indirectly beneficially own the securities owned by PVP V, PVPE V, PVPFF V and PVPSFF V. </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(b) The managing members of PVM V and Nashat may be deemed to share the power to vote or direct the voting of and to dispose or direct the disposition of the
securities of the Issuer that are beneficially owned by PVP V, PVPE V, PVPFF V and PVPSFF V. Each such person disclaims beneficial ownership of all securities other than those he or she owns directly, if any, or by virtue of his or her indirect pro
rata interest, as a member of PVM V, in the securities owned by PVP V, PVPE V, PVPFF V and PVPSFF V. PVM V may be deemed to have sole power to vote or direct the voting of and to dispose or direct the disposition of the securities of the Issuer that
are beneficially owned by PVP V, PVPE V, PVPFF V and PVPSFF V. </P>

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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(c) Except as described in this statement, none of the Reporting Persons has effected any transactions in the
Common Stock in the 60 days prior to the date of this statement. </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(d) Except as described in this statement, no person has the power to direct the receipt
of dividends on or the proceeds of sales of, the shares of Common Stock owned by the Reporting Persons. </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD ALIGN="left" VALIGN="top">Not applicable. </TD></TR></TABLE> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Item&nbsp;6. Contracts, Arrangements, Understandings or Relationships with Respect to
Securities of the Issuer. </U></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Each of PVP V, PVPE V, PVPFF V and PVPSFF V and certain other investors are party to a Fifth Amended and Restated
Investors&#146; Rights Agreement (the &#147;IRA&#148;) entered into with the (i)&nbsp;Issuer; (ii)&nbsp;the holders of Senior Preferred Stock (as defined therein) and the Purchaser (as listed therein); and (iii)&nbsp;the Initial Stockholders (as
listed therein). </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Reporting Persons are subject to a restricted period during the period ending 180 days after the date of the Prospectus, during
which the Reporting Persons have agreed, subject to limited exceptions, not to offer, pledge, sell, contract to sell, sell any options or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase,
lend, or otherwise transfer or dispose of, directly or indirectly, any shares of common stock beneficially owned by the Issuer or Reporting Persons or any securities so owned convertible into or exercisable or exchangeable for common stock or enter
into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the common stock, or publicly disclose the intention to make any such offer, pledge sale, contract, purchase, grant,
loan, transfer, or disposition, or enter into any such swap or other arrangement. The IRA is attached as Exhibit 4.1 to Issuer&#146;s Registration Statement on Form S-1 (File No.&nbsp;333-211555), and is incorporated herein by reference. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Issuer has entered into an indemnification agreement with each of its directors and executive officers, including Nashat. The indemnification agreement,
among other things, require the Issuer or will require the Issuer to indemnify Nashat (and in certain cases each of PVP V, PVPE V, PVPFF V and PVPSFF V) to the fullest extent permitted by Delaware law, including indemnification of expenses such as
attorneys&#146; fees, judgments, fines and settlement amounts incurred by Nashat in any action or proceeding, including any action or proceeding by or in right of the Issuer, arising out of his services as a director. The form of Indemnification
Agreement for the Issuer&#146;s directors and officers is attached as Exhibit 10.5 to the Issuer&#146;s Registration Statement on Form S-1 (File No.&nbsp;333-211555), and is incorporated herein by reference. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Item&nbsp;7. Material to be Filed as Exhibits. </U></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Exhibit
A&#151;Joint Filing Agreement </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Exhibit B &#150; IRA, filed on May&nbsp;24, 2016 as Exhibit 4.1 to the Issuer&#146;s Registration Statement on Form S-1
(File No.&nbsp;333-211555), and incorporated herein by reference. </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Exhibit C&#151;Form of Indemnification Agreement for board members and senior
management, filed on May&nbsp;24, 2016 as Exhibit 10.5 to the Issuer&#146;s Registration Statement on Form S-1 (File No.&nbsp;333-211555), and incorporated herein by reference. </P>

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 <P STYLE="margin-top:12pt; 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">Date: July&nbsp;7, 2016 </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
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<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="5">POLARIS VENTURE PARTNERS V, L.P.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="4"></TD></TR>
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<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3">Polaris Venture Management Co. V, L.L.C.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="4"></TD></TR>
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<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">*</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3">Managing Member</TD></TR>
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<TD HEIGHT="16" COLSPAN="5"></TD></TR>
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<TD VALIGN="top" COLSPAN="5"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">POLARIS VENTURE PARTNERS</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">ENTREPRENEURS&#146; FUND V, L.P.</P></TD></TR>
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<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3">Polaris Venture Management Co. V, L.L.C.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="4"></TD></TR>
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<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">*</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3">Managing Member</TD></TR>
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<TD HEIGHT="16" COLSPAN="5"></TD></TR>
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<TD VALIGN="top" COLSPAN="5"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">POLARIS VENTURE PARTNERS</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">FOUNDERS&#146; FUND V, L.P.</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="5"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="5">By: Polaris Venture Management Co. V, L.L.C.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="4"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">*</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3">Managing Member</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="5"></TD></TR>
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<TD VALIGN="top" COLSPAN="5"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">POLARIS VENTURE PARTNERS SPECIAL</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">FOUNDERS&#146; FUND V, L.P.</P></TD></TR>
<TR STYLE="font-size:1pt">
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<TD HEIGHT="16" COLSPAN="4"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3">Polaris Venture Management Co. V, L.L.C.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="4"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">*</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Managing Member</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
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<TD VALIGN="top" COLSPAN="5"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">POLARIS VENTURE MANAGEMENT CO. V, L.L.C.</P></TD></TR>
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<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">*</P></TD></TR>
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<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3">Managing Member</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="5"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="5">JONATHAN A. FLINT</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="4"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Jonathan A. Flint</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="5">Jonathan A. Flint</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="5"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="5">TERRANCE G. MCGUIRE</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="4"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Terrance G. McGuire</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="5">Terrance G. McGuire</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="5"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="5">AMIR NASHAT</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="4"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Amir Nashat</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" COLSPAN="3">Amir Nashat</TD></TR></TABLE></DIV> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="3%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="95%"></TD></TR>

<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">*By:<U> </U></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Mary Blair</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Name: <U></U></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Mary Blair</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Attorney-in-Fact</TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">[This Schedule 13D was executed pursuant to a Power of Attorney. Note that copies of the applicable Powers of
Attorney are already on file with the appropriate agencies.] </P>
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<DOCUMENT>
<TYPE>EX-99.A
<SEQUENCE>2
<FILENAME>d226416dex99a.htm
<DESCRIPTION>EX-99.A
<TEXT>
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<TITLE>EX-99.A</TITLE>
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<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">

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<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">CUSIP No. 816212104</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right"> Page
 1
5 of 16</TD></TR></TABLE> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><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">AGREEMENT REGARDING THE JOINT FILING OF </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">SCHEDULE 13D </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The undersigned, being duly
authorized thereunto, hereby execute this agreement as an exhibit to this Schedule 13D to evidence the agreement of the below-named parties, in accordance with the rules promulgated pursuant to the Securities Exchange Act of 1934, to file this
Schedule jointly on behalf of each such party. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Date: July&nbsp;7, 2016 </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
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<TD WIDTH="6%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">POLARIS VENTURE PARTNERS V, L.P.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">By: Polaris Venture Management Co. V, L.L.C.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">*</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Managing Member</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">POLARIS VENTURE PARTNERS ENTREPRENEURS&#146; FUND V, L.P.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">By: Polaris Venture Management Co. V, L.L.C.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">*</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Managing Member</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">POLARIS VENTURE PARTNERS FOUNDERS&#146; FUND V, L.P.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">By: Polaris Venture Management Co. V, L.L.C.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">*</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Managing Member</TD></TR>
</TABLE></DIV>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">



<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">

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<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">CUSIP No. 816212104</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right">Page 16 of 16</TD></TR></TABLE> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
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<TD WIDTH="6%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">POLARIS VENTURE PARTNERS SPECIAL FOUNDERS&#146; FUND V, L.P.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">By: Polaris Venture Management Co. V, L.L.C.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">*</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Managing Member</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">POLARIS VENTURE MANAGEMENT CO. V, L.L.C.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman" ALIGN="center">*</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Managing Member</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">JONATHAN A. FLINT</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Jonathan A. Flint</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Jonathan A. Flint</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">TERRANCE G. MCGUIRE</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Terrance G. McGuire</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Terrance G. McGuire</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3">AMIR NASHAT</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Amir Nashat</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Amir Nashat</TD></TR></TABLE></DIV> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TR>
<TD WIDTH="13%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="86%"></TD></TR>

<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">*By:<U> </U></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Mary Blair</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Name:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Mary Blair</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Attorney-in-Fact</TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">[This Schedule 13D was executed pursuant to a Power of Attorney. Note that copies of the applicable Powers of
Attorney are already on file with the appropriate agencies.] </P>
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</SEC-DOCUMENT>
