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
§§240.13d-1(e),
240.13d-1(f)
or
240.13d-1(g),
check the following box: ☐
The information required on the remainder of this cover page
shall not be deemed to be filed for the purpose of Section 18 of the Securities Exchange Act of 1934 (Act) 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).
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|
|
|
|
|
|
1.
|
|
Names of
Reporting Persons.
Polaris Venture Partners VI, L.P. (PVP
VI)
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2.
|
|
Check the Appropriate Box if a Member
of a Group (See Instructions)
(a) ☐ (b) ☒
|
3.
|
|
SEC Use Only
|
4.
|
|
Source of Funds (See Instructions)
WC
|
5.
|
|
Check if Disclosure of Legal
Proceedings Is Required Pursuant to Items 2(d) or 2(e)
☐
|
6.
|
|
Citizenship or Place of
Organization
Delaware
|
Number of
Shares
Beneficially
Owned by
Each
Reporting
Person
With
|
|
7.
|
|
Sole Voting Power
1,697,924 shares, except that (i) Polaris Venture Management Co. VI, L.L.C. (PVM
VI), the general partner of PVP VI, may be deemed to have sole power to vote these shares; and (ii) Jonathan A. Flint (Flint), Terrance G. McGuire (McGuire), Brian Chee (Chee), David Barrett
(Barrett), Amir Nashat (Nashat) and Bryce Youngren (Youngren and collectively with Flint, McGuire, Chee, Barrett and Nashat, the Managing Members) are the managing members of PVM VI, and may be deemed
to have shared power to vote these shares.
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|
8.
|
|
Shared Voting Power
See response to row 7.
|
|
9.
|
|
Sole Dispositive Power
1,697,924 shares, except that (i) PVM VI, the general partner of PVP VI, may be deemed to
have sole power to dispose of these shares; and (ii) the Managing Members may be deemed to have shared power to dispose of these shares.
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|
10.
|
|
Shared Dispositive Power
See response to row 9.
|
11.
|
|
Aggregate Amount Beneficially Owned by Each Reporting Person
1,697,924
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12.
|
|
Check if the Aggregate Amount in Row
(11) Excludes Certain Shares (See Instructions)
☐
|
13.
|
|
Percent of Class Represented by Amount
in Row (11)
4.1%
|
14.
|
|
Type of Reporting Person (See
Instructions)
PN
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|
|
|
|
|
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1.
|
|
Names of
Reporting Persons.
Polaris Venture Founders Fund VI, L.P. (PVPFF
VI)
|
2.
|
|
Check the Appropriate Box if a Member
of a Group (See Instructions)
(a) ☐ (b) ☒
|
3.
|
|
SEC Use Only
|
4.
|
|
Source of Funds (See Instructions)
WC
|
5.
|
|
Check if Disclosure of Legal
Proceedings Is Required Pursuant to Items 2(d) or 2(e)
☐
|
6.
|
|
Citizenship or Place of
Organization
Delaware
|
Number of
Shares
Beneficially
Owned by
Each
Reporting
Person
With
|
|
7.
|
|
Sole Voting Power
99,220 shares, except that (i) PVM VI, the general partner of PVPFF VI, may be deemed to
have sole power to vote these shares; and (ii) the Managing Members may be deemed to have shared power to vote these shares.
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|
8.
|
|
Shared Voting Power
See response to row 7.
|
|
9.
|
|
Sole Dispositive Power
99,220 shares, except that (i) PVM VI, the general partner of PVPFF VI, may be deemed to
have sole power to dispose of these shares; and (ii) the Managing Members may be deemed to have shared power to dispose of these shares.
|
|
10.
|
|
Shared Dispositive Power
See response to row 9.
|
11.
|
|
Aggregate Amount Beneficially Owned by Each Reporting Person
99,220
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12.
|
|
Check if the Aggregate Amount in Row
(11) Excludes Certain Shares (See Instructions)
☐
|
13.
|
|
Percent of Class Represented by Amount
in Row (11)
0.2%
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14.
|
|
Type of Reporting Person (See
Instructions)
PN
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|
|
|
|
|
|
|
1.
|
|
Names of
Reporting Persons.
Polaris Venture Management Co. VI, L.L.C. (PVM
VI)
|
2.
|
|
Check the Appropriate Box if a Member
of a Group (See Instructions)
(a) ☐ (b) ☒
|
3.
|
|
SEC Use Only
|
4.
|
|
Source of Funds (See Instructions)
AF
|
5.
|
|
Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)
☐
|
6.
|
|
Citizenship or Place of
Organization
Delaware
|
Number of
Shares
Beneficially
Owned by
Each
Reporting
Person
With
|
|
7.
|
|
Sole Voting Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that the Managing Members may be deemed to have shared power to vote these shares.
|
|
8.
|
|
Shared Voting Power
See response to row 7.
|
|
9.
|
|
Sole Dispositive Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that the Managing Members may be deemed to have shared power to dispose of these shares.
|
|
10.
|
|
Shared Dispositive Power
See response to row 9.
|
11.
|
|
Aggregate Amount Beneficially Owned by Each Reporting Person
1,797,144 shares
|
12.
|
|
Check if the Aggregate Amount in Row
(11) Excludes Certain Shares (See Instructions)
☐
|
13.
|
|
Percent of Class Represented by Amount
in Row (11)
4.3%
|
14.
|
|
Type of Reporting Person (See
Instructions)
OO
|
|
|
|
|
|
|
|
1.
|
|
Names of
Reporting Persons.
Jonathan A. Flint (Flint)
|
2.
|
|
Check the Appropriate Box if a Member
of a Group (See Instructions)
(a) ☐ (b) ☒
|
3.
|
|
SEC Use Only
|
4.
|
|
Source of Funds (See Instructions)
AF
|
5.
|
|
Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)
☐
|
6.
|
|
Citizenship or Place of
Organization
USA
|
Number of
Shares
Beneficially
Owned by
Each
Reporting
Person
With
|
|
7.
|
|
Sole Voting Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to vote PVP VIs and PVPFF VIs shares (collectively, the Fund VI Shares); and (ii)
McGuire, Chee, Barrett, Nashat and Youngren, as managing members of PVM VI, may be deemed to have shared power to vote the Fund VI Shares.
|
|
8.
|
|
Shared Voting Power
See response to row 7.
|
|
9.
|
|
Sole Dispositive Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to dispose of the Fund VI Shares; and (ii) McGuire, Chee, Barrett, Nashat and Youngren, as managing
members of PVM VI, may be deemed to have shared power to dispose of the Fund VI Shares.
|
|
10.
|
|
Shared Dispositive Power
See response to row 9.
|
11.
|
|
Aggregate Amount Beneficially Owned by Each Reporting Person
1,797,144 shares
|
12.
|
|
Check if the Aggregate Amount in Row
(11) Excludes Certain Shares (See Instructions)
☐
|
13.
|
|
Percent of Class Represented by Amount
in Row (11)
4.3%
|
14.
|
|
Type of Reporting Person (See
Instructions)
IN
|
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|
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|
1.
|
|
Names of
Reporting Persons.
Terrance G. McGuire (McGuire)
|
2.
|
|
Check the Appropriate Box if a Member
of a Group (See Instructions)
(a) ☐ (b) ☒
|
3.
|
|
SEC Use Only
|
4.
|
|
Source of Funds (See Instructions)
AF
|
5.
|
|
Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)
☐
|
6.
|
|
Citizenship or Place of
Organization
USA
|
Number of
Shares
Beneficially
Owned by
Each
Reporting
Person
With
|
|
7.
|
|
Sole Voting Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to vote the Fund VI Shares; and (ii) Flint, Chee, Barrett, Nashat and Youngren, as managing members of PVM
VI, may be deemed to have shared power to vote the Fund VI Shares.
|
|
8.
|
|
Shared Voting Power
See response to row 7.
|
|
9.
|
|
Sole Dispositive Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to dispose of the Fund VI Shares; and (ii) Flint, Chee, Barrett, Nashat and Youngren, as managing members
of PVM VI, may be deemed to have shared power to dispose of the Fund VI Shares.
|
|
10.
|
|
Shared Dispositive Power
See response to row 9.
|
11.
|
|
Aggregate Amount Beneficially Owned by Each Reporting Person
1,797,144 shares
|
12.
|
|
Check if the Aggregate Amount in Row
(11) Excludes Certain Shares (See Instructions)
☐
|
13.
|
|
Percent of Class Represented by Amount
in Row (11)
4.3%
|
14.
|
|
Type of Reporting Person (See
Instructions)
IN
|
|
|
|
|
|
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1.
|
|
Names of
Reporting Persons.
Brian Chee (Chee)
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2.
|
|
Check the Appropriate Box if a Member
of a Group (See Instructions)
(a) ☐ (b) ☒
|
3.
|
|
SEC Use Only
|
4.
|
|
Source of Funds (See Instructions)
AF
|
5.
|
|
Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)
☐
|
6.
|
|
Citizenship or Place of
Organization
USA
|
Number of
Shares
Beneficially
Owned by
Each
Reporting
Person
With
|
|
7.
|
|
Sole Voting Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to vote the Fund VI Shares; and (ii) Flint, McGuire, Barrett, Nashat and Youngren, as managing members of
PVM VI, may be deemed to have shared power to vote the Fund VI Shares.
|
|
8.
|
|
Shared Voting Power
See response to row 7.
|
|
9.
|
|
Sole Dispositive Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to dispose of the Fund VI Shares; and (ii) Flint, McGuire, Barrett, Nashat and Youngren, as managing
members of PVM VI, may be deemed to have shared power to dispose of the Fund VI Shares.
|
|
10.
|
|
Shared Dispositive Power
See response to row 9.
|
11.
|
|
Aggregate Amount Beneficially Owned by Each Reporting Person
1,797,144 shares
|
12.
|
|
Check if the Aggregate Amount in Row
(11) Excludes Certain Shares (See Instructions)
☐
|
13.
|
|
Percent of Class Represented by Amount
in Row (11)
4.3%
|
14.
|
|
Type of Reporting Person (See
Instructions)
IN
|
|
|
|
|
|
|
|
1.
|
|
Names of
Reporting Persons.
David Barrett (Barrett)
|
2.
|
|
Check the Appropriate Box if a Member
of a Group (See Instructions)
(a) ☐ (b) ☒
|
3.
|
|
SEC Use Only
|
4.
|
|
Source of Funds (See Instructions)
AF
|
5.
|
|
Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)
☐
|
6.
|
|
Citizenship or Place of
Organization
USA
|
Number of
Shares
Beneficially
Owned by
Each
Reporting
Person
With
|
|
7.
|
|
Sole Voting Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to vote the Fund VI Shares; and (ii) Flint, McGuire, Chee, Nashat and Youngren, as managing members of PVM
VI, may be deemed to have shared power to vote the Fund VI Shares.
|
|
8.
|
|
Shared Voting Power
See response to row 7.
|
|
9.
|
|
Sole Dispositive Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to dispose of the Fund VI Shares; and (ii) Flint, McGuire, Chee, Nashat and Youngren, as managing members
of PVM VI, may be deemed to have shared power to dispose of the Fund VI Shares.
|
|
10.
|
|
Shared Dispositive Power
See response to row 9.
|
11.
|
|
Aggregate Amount Beneficially Owned by Each Reporting Person
1,797,144 shares
|
12.
|
|
Check if the Aggregate Amount in Row
(11) Excludes Certain Shares (See Instructions)
☐
|
13.
|
|
Percent of Class Represented by Amount
in Row (11)
4.3%
|
14.
|
|
Type of Reporting Person (See
Instructions)
IN
|
|
|
|
|
|
|
|
1.
|
|
Names of
Reporting Persons.
Amir Nashat (Nashat)
|
2.
|
|
Check the Appropriate Box if a Member
of a Group (See Instructions)
(a) ☐ (b) ☒
|
3.
|
|
SEC Use Only
|
4.
|
|
Source of Funds (See Instructions)
AF
|
5.
|
|
Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)
☐
|
6.
|
|
Citizenship or Place of
Organization
USA
|
Number of
Shares
Beneficially
Owned by
Each
Reporting
Person
With
|
|
7.
|
|
Sole Voting Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to vote the Fund VI Shares; and (ii) Flint, McGuire, Chee, Barrett and Youngren, as managing members of
PVM VI, may be deemed to have shared power to vote the Fund VI Shares.
|
|
8.
|
|
Shared Voting Power
See response to row 7.
|
|
9.
|
|
Sole Dispositive Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to dispose of the Fund VI Shares; and (ii) Flint, McGuire, Chee, Barrett and Youngren, as managing members
of PVM VI, may be deemed to have shared power to dispose of the Fund VI Shares.
|
|
10.
|
|
Shared Dispositive Power
See response to row 9.
|
11.
|
|
Aggregate Amount Beneficially Owned by Each Reporting Person
1,797,144 shares
|
12.
|
|
Check if the Aggregate Amount in Row
(11) Excludes Certain Shares (See Instructions)
☐
|
13.
|
|
Percent of Class Represented by Amount
in Row (11)
4.3%
|
14.
|
|
Type of Reporting Person (See
Instructions)
IN
|
|
|
|
|
|
|
|
1.
|
|
Names of
Reporting Persons.
Bryce Youngren (Youngren)
|
2.
|
|
Check the Appropriate Box if a Member
of a Group (See Instructions)
(a) ☐ (b) ☒
|
3.
|
|
SEC Use Only
|
4.
|
|
Source of Funds (See Instructions)
AF
|
5.
|
|
Check if Disclosure of Legal
Proceedings is Required Pursuant to Items 2(d) or 2(e)
☐
|
6.
|
|
Citizenship or Place of
Organization
USA
|
Number of
Shares
Beneficially
Owned by
Each
Reporting
Person
With
|
|
7.
|
|
Sole Voting Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to vote the Fund VI Shares; and (ii) Flint, McGuire, Chee, Barrett and Nashat, as managing members of PVM
VI, may be deemed to have shared power to vote the Fund VI Shares.
|
|
8.
|
|
Shared Voting Power
See response to row 7.
|
|
9.
|
|
Sole Dispositive Power
1,797,144 shares, of which 1,697,924 shares are directly owned by PVP VI and 99,220
shares are directly owned by PVPFF VI, except that (i) PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to have sole power to dispose of the Fund VI Shares; and (ii) Flint, McGuire, Chee, Barrett and Nashat, as managing members
of PVM VI, may be deemed to have shared power to dispose of the Fund VI Shares.
|
|
10.
|
|
Shared Dispositive Power
See response to row 9.
|
11.
|
|
Aggregate Amount Beneficially Owned by Each Reporting Person
1,797,144 shares
|
12.
|
|
Check if the Aggregate Amount in Row
(11) Excludes Certain Shares (See Instructions)
☐
|
13.
|
|
Percent of Class Represented by Amount
in Row (11)
4.3%
|
14.
|
|
Type of Reporting Person (See
Instructions)
IN
|
CUSIP No. 28106W103
SCHEDULE 13D
This Amendment No. 3
(Amendment No. 3) amends and supplements the Schedule 13D originally filed with the Securities and Exchange Commission (the SEC) on May 16, 2016 (the Schedule 13D), Amendment No. 1 to the Schedule
13D filed with the SEC on September 19, 2016 and Amendment No. 2 (Amendment No. 2) to the Schedule 13D filed with the SEC on May 22, 2017, by Polaris Venture Partners VI, L.P. (PVP VI), Polaris Venture
Founders Fund VI, L.P. (PVPFF VI), Polaris Venture Management Co. VI, L.L.C. (PVM VI), Jonathan A. Flint (Flint), Terrance G. McGuire (McGuire), Brian Chee (Chee), David Barrett
(Barrett), Amir Nashat (Nashat) and Bryce Youngren (Youngren and together with, PVP VI, PVPFF VI, PVM VI, Flint, McGuire, Chee, Barrett, and Nashat, collectively, the Reporting Persons), with respect
to shares of Common Stock of the Issuer beneficially owned by the Reporting Persons. This Amendment No. 3 is being filed to report the disposition of Common Stock by PVP VI and PVPFF VI on September 1, 2017, September 5, 2017,
September 7, 2017, September 8, 2017, September 11, 2017, September 12, 2017, September 13, 2017 and September 14, 2017; all other information is as set forth in the Schedule 13D, Amendment No. 1 and Amendment
No. 2. Information given in response to each item shall be deemed incorporated by reference in all other items, as applicable. Capitalized terms used herein but not defined shall have the meanings ascribed thereto in the Schedule 13D.
Item 4. Purpose of Transaction.
Item 4 of the Original
Schedule 13D is hereby amended to add the following statements:
On September 1, 2017, PVP VI sold 70,859 shares of Common Stock on the open market
and PVPFF VI sold 4,141 shares of Common Stock on the open market.
On September 5, 2017, PVP VI sold 141,412 shares of Common Stock on the open
market and PVPFF VI sold 8,264 shares of Common Stock on the open market.
On September 7, 2017, PVP VI sold 118,337 shares of Common Stock on the
open market and PVPFF VI sold 6,915 shares of Common Stock on the open market.
On September 8, 2017, PVP VI sold 142,986 shares of Common Stock on
the open market and PVPFF VI sold 8,356 shares of Common Stock on the open market.
On September 11, 2017, PVP VI sold 82,609 shares of Common Stock
on the open market and PVPFF VI sold 4,827 shares of Common Stock on the open market.
On September 12, 2017, PVP VI sold 13,778 shares of Common
Stock on the open market and PVPFF VI sold 805 shares of Common Stock on the open market.
On September 13, 2017, PVP VI sold 212,578 shares of
Common Stock on the open market and PVPFF VI sold 12,422 shares of Common Stock on the open market.
On September 14, 2017, PVP VI sold 162,231
shares of Common Stock on the open market and PVPFF VI sold 9,480 shares of Common Stock on the open market.
Item 5. Interest in Securities of the
Issuer.
Items 5(a) and (c) of the Schedule 13D are hereby amended and restated in their entirety as follows:
The information below is based on a total of 41,627,446 shares of Common Stock outstanding as reported on Form
10-Q,
Quarterly Report Pursuant to Section 13 or 15(d) of the Security Exchange Act of 1934 filed with the Securities and Exchange Commission by the Issuer on August 9, 2017.
|
(a)
|
PVP VI directly beneficially owns 1,697,924 shares of Common Stock, or approximately 4.1% of the Common Stock outstanding. PVPFF VI directly beneficially owns 99,220 shares of Common Stock, or approximately 0.2% of the
Common Stock outstanding. PVM VI, as the general partner of PVP VI and PVPFF VI, may be deemed to indirectly beneficially own the securities owned by PVP VI and PVPFF VI. PVM VI, as general partner of PVP VI and PVPFF VI may be deemed to indirectly
beneficially own 1,797,144 shares of Common Stock, or approximately 4.3% of the Common Stock outstanding. Each of the Managing Members, in their respective capacities as managing members of PVM VI, may be deemed to indirectly beneficially own
1,797,144 shares of Common Stock, or approximately 4.3% of the Common Stock outstanding, aggregately owned by PVP VI and PVPFF VI.
|
|
(c)
|
Except as described in this statement and this Item 5(c), none of the Reporting Persons has effected any transactions in the Common Stock in the 60 days prior to the date of this statement.
|
Item 7. Material to be Filed as Exhibits.
|
|
|
Exhibit
|
|
Description
|
|
|
A
|
|
Agreement Regarding the Joint Filing of Schedule 13D
|
CUSIP No. 28106W103
SIGNATURE
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.
Date:
September 18, 2017
|
|
|
POLARIS VENTURE PARTNERS VI, L.P.
|
|
|
By:
|
|
Polaris Venture Management Co. VI, L.L.C.
|
|
|
By:
|
|
*
|
|
|
Authorized Signatory
|
|
POLARIS VENTURE PARTNERS FOUNDERS FUND VI, L.P.
|
|
|
By:
|
|
Polaris Venture Management Co. VI, L.L.C.
|
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By:
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*
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Authorized Signatory
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POLARIS VENTURE MANAGEMENT CO. VI, L.L.C.
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*
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Authorized Signatory
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JONATHAN A. FLINT
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By:
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*
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Jonathan A. Flint
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TERRANCE G. MCGUIRE
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By:
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*
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Terrance G. McGuire
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BRIAN CHEE
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By:
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*
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Brian Chee
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CUSIP No. 28106W103
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DAVID BARRETT
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By:
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*
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David Barrett
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AMIR NASHAT
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By:
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*
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Amir Nashat
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BRYCE YOUNGREN
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By:
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*
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Bryce Youngren
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*By:
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/s/ Max Eisenberg
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Name:
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Max Eisenberg
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Attorney-in-Fact
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[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.]