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Table of Contents 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 ( Mark One ) ☐ ☑ 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 : 001-39173 I - MAB ( Exact Name of Registrant as Specified in Its Charter ) N / A ( Translation of Registrant's Name Into English ) Cayman Islands ( Jurisdiction of Incorporation or Organization ) Suite 802 , West Tower , OmniVision , 88 Shangke Road , Pudong District Shanghai , 201210 People's Republic of China ( Address of Principal Executive Offices ) Jielun Zhu , Chief Financial Officer Suite 802 , West Tower , OmniVision , 88 Shangke Road , Pudong District Shanghai , 201210 People's Republic of China Phone : +86 21-6057-8000 Email : jielun.zhu@i-mabbiopharma.com ( Name , Telephone , Email and / or Facsimile number and Address of Company Contact Person ) Securities registered or to be registered pursuant to Section 12 ( b ) of the Act : Title of Each Class American depositary shares , each ten ( 10 ) American depositary shares representing twenty- three ( 23 ) ordinary shares Ordinary shares , par value US $ 0.0001 per share * Trading Symbol IMAB Name of Each Exchange On Which Registered The Nasdaq Stock Market LLC ( The Nasdaq Global Market ) The Nasdaq Stock Market LLC ( The Nasdaq Global Market )