    <SEC-DOCUMENT>0001193125-22-251791-index.html : 20220927
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    <ACCEPTANCE-DATETIME>20220927090625
    ACCESSION NUMBER:		0001193125-22-251791
    CONFORMED SUBMISSION TYPE:	424B3
    PUBLIC DOCUMENT COUNT:		10
    FILED AS OF DATE:		20220927
    DATE AS OF CHANGE:		20220927

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			MIDDLEFIELD BANC CORP
    		CENTRAL INDEX KEY:			0000836147
    		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
    		IRS NUMBER:				341585111
    		STATE OF INCORPORATION:			OH

    	FILING VALUES:
    		FORM TYPE:		424B3
    		SEC ACT:		1933 Act
    		SEC FILE NUMBER:	333-266694
    		FILM NUMBER:		221267473

    	BUSINESS ADDRESS:
    		STREET 1:		15985 E HIGH ST
    		STREET 2:		P O BOX 35
    		CITY:			MIDDLEFILED
    		STATE:			OH
    		ZIP:			44062-9263
    		BUSINESS PHONE:		4406321666

    	MAIL ADDRESS:
    		STREET 1:		15985 EAST HIGH STREET
    		STREET 2:		P O BOX 35
    		CITY:			MIDDLEFIELD
    		STATE:			OH
    		ZIP:			44062-9263
    </SEC-HEADER>
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    <TYPE>424B3
    <SEQUENCE>1
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    <DESCRIPTION>424B3
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    <SEQUENCE>4
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    <DESCRIPTION>GRAPHIC
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    <SEQUENCE>8
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    <DESCRIPTION>GRAPHIC
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