X0508 4 2024-09-06 0000836147 MIDDLEFIELD BANC CORP MBCN 0002008413 Winters Sarah A 15985 EAST HIGH STREET MIDDLEFIELD OH 44062 1 EVP/CHRO 0 Conditional Stock Award 2024-09-06 4 A 0 2561 A 2027-09-06 Common Stock 2561 2561 D The award represents a grant of restricted stock which vests ratably over a three-year period provided that Mrs. Winters remains continuously employed by Middlefield as of each vesting date. Until the award vests, the award confers no right to vote, no right to dividends, and no other shareholder rights to the recipient. Each restricted stock unit represents the right to receive, at settlement, one share of common stock. /s/ Sarah A. Winters by Julie E. Shaw Power of Attorney 2024-09-10