X0306 4 2021-05-05 0 0000836147 MIDDLEFIELD BANC CORP MBCN 0001543854 Moore Charles O 15985 EAST HIGH STREET MIDDLEFIELD OH 44062 0 1 0 0 President, Central Ohio Region Common Stock 2021-05-05 4 P 0 1000 22.901 A 4318.211 D Price reported in Column 4 is a weighted average price based on various purchase prices within a range. For the 1,000 shares, the per share purchase prices ranged from $22.800 to $22.956. The reporting person will, upon request, provide to MBCN, any security holder of MBCN, and the staff of the Securities and Exchange Commission full information regarding the number of shares purchased in each separate price within the range set forth in this footnote to this Form 4. Charles O. Moore by James R. Heslop, II Power of Attorney 2021-05-07