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( Mark One ) UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31 , 2020 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO FORM 10 - K DELAWARE ( State or other jurisdiction of incorporation or organization ) Commission File Number 001-38276 APELLIS PHARMACEUTICALS , INC . ( Exact name of registrant as specified in its charter ) 100 Fifth Avenue Waltham , MA ( Address of principal executive offices ) Title of each class Common Stock , $ 0.0001 par value Large accelerated filer Non - accelerated filer 27-1537290 ( I.R.S. Employer Identification No. ) 02451 ( Zip Code ) Registrant's telephone number , including area code : ( 617 ) 977-5700 Securities registered pursuant to Section 12 ( b ) of the Act : Trading Symbol ( s ) APLS per share Securities registered pursuant to Section 12 ( g ) of the Act : None Name of each exchange on which registered Nasdaq Global Select Market Indicate by check mark if the registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . YES NO Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 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 the definitions of “ large accelerated filer , ” “ accelerated filer , ” “ smaller reporting company , " and " emerging growth company " in Rule 12b - 2 of the Exchange Act . Accelerated filer Small 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 . ロロロ 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 ) ) 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 Exchange Act ) . YES NO > As of June 30 , 2020 , the aggregate market value of the voting and non - voting common equity held by non - affiliates of the registrant , based on the closing price of the shares of common stock on the Nasdaq Global Select Stock Market on such date , was $ 1,953,553,262 . The number of shares of the registrant's common stock , par value $ 0.0001 per share outstanding as of February 22 , 2021 was 80,375,365 . DOCUMENTS INCORPORATED BY REFERENCE The registrant intends to file a definitive proxy statement pursuant to Regulation 14A in connection with its 2021 Annual Meeting of Stockholders within 120 days of the end of the registrant's fiscal year ended December 31 , 2020. Portions of such proxy statement are incorporated by reference into Part III of this Annual Report on Form 10 - K .