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UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON , D.C. 20549 FORM 20 - F REGISTRATION STATEMENT PURSUANT TO SECTION 12 ( B ) OR 12 ( G ) OF THE SECURITIES EXCHANGE ACT OF 1934 OR ☒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 OR SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15 ( D ) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of event requiring this shell company report For the transition period from to Commission file number 001-33869 STAR BULK CARRIERS CORP . ( Exact name of Registrant as specified in its charter ) Not Applicable ( Translation of Registrant's name into English ) Republic of the Marshall Islands ( Jurisdiction of incorporation or organization ) c / o Star Bulk Management Inc. , 40 Agiou Konstantinou Str . , Maroussi 15124 , Athens , Greece ( Address of principal executive offices ) Petros Pappas , 011 30 210 617 8400 , mgt@starbulk.com , c / o Star Bulk Management Inc. , 40 Agiou Konstantinou Str . Maroussi 15124 , Athens , Greece ( Name , telephone , E - mail and / or Facsimile number and Address of Company Contact Person ) Securities registered or to be registered pursuant to Section 12 ( b ) of the Act . Trading Symbol ( s ) SBLK SBLKZ Name of exchange on which registered Nasdaq Global Select Market Nasdaq Global Select Market Title of each class Common Shares , par value $ 0.01 per share 8.30 % Senior Notes due 2022 Securities registered or to be registered pursuant to Section 12 ( g ) of the Act : None Securities for which there is a reporting obligation pursuant to Section 15 ( d ) of the Act : None