X0508 4 2025-12-17 0000836147 MIDDLEFIELD BANC CORP MBCN 0001976448 Wilson Thomas M 15985 EAST HIGH STREET MIDDLEFIELD OH 44062 1 EVP-Chief Strategy Officer 0 Common Stock 2025-12-17 4 A 0 1651 37 A 9528 D Common Stock 2025-12-17 4 F 0 480 37 D 9048 D Common Stock 12498 I held in IRA Conditional Stock Award 2027-09-06 Common Stock 1708 1708 D Conditional Stock Award 2028-01-14 Common Stock 2685 2685 D Amendment of conditional stock award agreement resulting in acceleration of restricted stock grants. The restricted stock award was originally granted on March 10, 2023, and provides for vesting on the third anniversary of the award. The award represents grant of restricted stock which vests ratably over a three-year period provided that Mr. Wilson 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. The details of the vesting conditions may be found in a Form 8K filing dated January 17, 2025 Each restricted stock unit represents the right to receive, at settlement, one share of common stock. The award represents a grant of restricted stock which vests ratably over a three-year period provided that Mr. Wilson 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. The details of the vesting conditions may be found in a Form 8K filed dated September 4, 2025. /s/ Thomas M. Wilson by Julie E. Shaw Power of Attorney 2025-12-18