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Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON , D.C. 20549 ( Mark One ) ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31 , 2020 Delaware ( State or other jurisdiction of incorporation or organization ) FORM 10 - K TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from 11 Hurley Street Cambridge , Massachusetts ( Address of principal executive offices ) or Title of each class Common Stock , $ 0.0001 par value per share to EDITAS MEDICINE , INC . ( Exact name of registrant as specified in its charter ) Commission File Number 001-37687 ( 617 ) 401-9000 ( Registrant's telephone number , including area code ) Securities registered pursuant to Section 12 ( b ) of the Act : Trading Symbol ( s ) . 46-4097528 ( I.R.S. Employer Identification No. ) EDIT Securities registered pursuant to Section 12 ( g ) of the Act : None 02141 ( Zip Code ) Name of each exchange on which registered The Nasdaq Stock Market LLC No Indicate by check mark if the registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . Yes Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15 ( d ) of the Act . Yes No Indicate by check mark whether the registrant ( 1 ) has filed all reports required to be filed by Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 during the preceding 12 months ( or for such shorter period that the registrant was required to file such reports ) , and ( 2 ) has been subject to such filing requirements for the past 90 days . Yes NO Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S - T ( § 232.405 of this chapter ) during the preceding 12 months ( or for such shorter period that the registrant was required to submit such files ) . Yes No Indicate by check mark whether the registrant is a large accelerated filer , an accelerated filer , a non - accelerated filer , a smaller reporting company , or an emerging growth company . See definitions of " large accelerated filer , " " accelerated filer , " " smaller reporting company , " and " emerging growth company " in Rule 12b - 2 of the Exchange Act . Large accelerated filer Accelerated filer Non - accelerated filer Smaller reporting company Emerging growth company If an emerging growth company , indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13 ( a ) of the Exchange Act . Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial reporting under Section 404 ( b ) of the Sarbanes - Oxley Act ( 15 U.S.C. 7262 ( b ) ) by the registered public accounting firm that prepared or issued its audit report . Indicate by check mark whether the registrant is a shell company ( as defined in Rule 12b - 2 of the Act ) . Yes No As of June 30 , 2020 , the last business day of the registrant's most recently completed second fiscal quarter , the aggregate market value of the registrant's Common Stock held by non - affiliates of the registrant was approximately $ 1,840,064,425 based upon the closing price of the registrant's Common Stock on June 30 , 2020 . The number of shares of the registrant's Common Stock outstanding as of February 14 , 2021 was 67,362,791 . DOCUMENTS INCORPORATED BY REFERENCE Portions of the registrant's definitive proxy statement for its 2021 Annual Meeting of Stockholders to be filed pursuant to Regulation 14A within 120 days of the end of the registrant's fiscal year ended December 31 , 2020 are incorporated by reference into Part III of this Annual Report on Form 10 - K to the extent stated herein .