Middlefield Banc(MBCN) - 2022 Q4 - Annual Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K Title of Each Class MBCN Name of Each Exchange on Which Registered Common Stock, Without Par Value Trading Symbol The NASDAQ Stock Market, LLC (NASDAQ Capital Market) (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, 2022 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period f ...