13D Filing: Polaris Venture Partners VI, L.P. and Editas Medicine Inc (EDIT)

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You can access the original SEC filing by clicking here.

Ownership Summary Table

Name Sole Voting Power Shared Voting Power Sole Dispositive Power Shared Dispositive Power Aggregate Amount Owned Power Percent of Class
Polaris Venture Partners VI 1,697,924 1,697,924 1,697,924 4.1%
Polaris Venture Founders 146 Fund VI 99,220 99,220 99,220 0.2%
Polaris Venture Management Co. VI 1,797,144 1,797,144 1,797,144 4.3%
Jonathan A. Flint ( 147 Flint 148 ) 1,797,144 1,797,144 1,797,144 4.3%
Terrance G. McGuire ( 147 McGuire 148 ) 1,797,144 1,797,144 1,797,144 4.3%
Brian Chee ( 147 Chee 148 ) 1,797,144 1,797,144 1,797,144 4.3%
David Barrett ( 147 Barrett 148 ) 1,797,144 1,797,144 1,797,144 4.3%
Amir Nashat ( 147 Nashat 148 ) 1,797,144 1,797,144 1,797,144 4.3%
Bryce Youngren ( 147 Youngren 148 ) 1,797,144 1,797,144 1,797,144 4.3%

Page 1 of 14 – SEC Filing

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 3)*

EDITAS
MEDICINE, INC.

(Name of Issuer)

Common Stock, $0.001 par value

(Title of Class of Securities)

28106W103

(CUSIP Number)

Polaris Partners

One Marina Park Drive

10th Floor

Boston, MA
02210

Gunderson Dettmer Stough Villeneuve

Franklin & Hachigian, LLP

One Marina Park Drive, Suite 900

Boston, MA 02210

Attn:
Jay K. Hachigian, Esq.

(617) 648-9100

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

September 8, 2017

(Date of Event which Requires Filing of this Statement)

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:  ☐

Note: Schedules filed in paper format shall
include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

* The remainder of this cover page shall be filled out for a reporting persons 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.

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).

Follow Editas Medicine Inc.

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