UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the Registrant  þ☒                             Filed by a Party other than the Registrant  ¨☐

Check the appropriate box:

MIDDLEFIELD BANC CORP.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

April 4, 20162019

Dear Shareholders:Shareholder:

You are cordially invited to attend the 20162019 Annual Meeting of Shareholders of Middlefield Banc Corp. The meeting will be held on Wednesday, May 11, 2016,15, 2019, 1:00 p.m. local time at SunValley Banquet & Party Center, 10000 Edwards Lane, Aurora, Ohio, 44202. The attached Notice of Annual Meeting of Shareholders and proxy statement discuss the business to be conducted at the meeting.

Your vote is important, regardless of the number of shares you own.Please read the enclosed proxy statement and then complete, sign, and date the enclosed proxy card and return it in the accompanying postage-paid return envelope as promptly as possible.possible. You may also use the Internet to vote by following the instructions on your proxy cardcard.. This will not prevent you from voting in person, but it will ensure that your vote is counted.

Thank you for your attention to this important matter.

Sincerely,

Sincerely,

Carolyn J. Turk

Chairman of the Board

Carolyn J. Turk

Chairman of the Board

15985 East High Street, P.O. Box 35 • Middlefield, Ohio 44062 •440/632-1666 •888/801-1666 •440/632-1700 (FAX) • www.middlefieldbank.com

www.middlefieldbank.bank

MIDDLEFIELD BANC CORP.

15985 East High Street

P.O. Box 35

Middlefield, Ohio 44062

(440)632-1666

NOTICEOF ANNUAL MEETINGOF SHAREHOLDERS

Notice is hereby given that the 20162019 Annual Meeting of Shareholders of Middlefield Banc Corp. will be held at SunValley Banquet & Party Center, 10000 Edwards Lane, Aurora, Ohio, 44202, on Wednesday, May 11, 2016,15, 2019, at 1:00 p.m. local time.

A proxy and a proxy statement for the 20162019 Annual Meeting of Shareholders are enclosed. The purpose of the annual meeting is to consider and act upon –

The Board of Directors is not aware of any other business to be presented at the annual meeting. Any action may be taken on the foregoing proposals at the 20162019 annual meeting on the date specified or on any date or dates to which the annual meeting is adjourned or postponed. The record date for determining shareholders entitled to vote at the meeting is March 21, 2016.2019.

Shareholders have a choice of voting on the Internet or by mailing a traditional proxy card. Your vote is important. We therefore urge you to vote promptly by using the Internet or by signing, dating, and returning the enclosed proxy card in the postage-paid return envelope provided, regardless of whether you expect to attend the annual meeting in person. If you vote by Internet, you do not need to return the proxy card. Internet voting information is provided on the proxy card.

Important Notice Regarding the Availability of Proxy Materials for the Shareholder Meeting to be held on May 11, 2016. 15, 2019. This Proxy Statement, the Proxy Card, the Chairman’s letter, and the Annual Report on Form10-K are available at www.middlefieldbank.comwww.middlefieldbank.bank.

To obtain directions to attend the annual meeting and vote in person, please contact our corporate headquarters at (440)632-1666or (888)801-1666 during regular business hours.

By Order of the Board of Directors,

Carolyn J. Turk

Kathleen M. Johnson

SecretaryChairman of the Board

Middlefield, Ohio

April 4, 20162019

THANKYOUFORACTINGPROMPTLY

MIDDLEFIELD BANC CORP.

15985 East High Street

P.O. Box 35

Middlefield, Ohio 44062

(440)632-1666

PROXY STATEMENT

Middlefield Banc Corp., an Ohio corporation, is furnishing this proxy statement to you on behalf of the board of directors to solicit your proxy for use at the 20162019 Annual Meeting of Shareholders. The annual meeting will be held on Wednesday, May 11, 2016,15, 2019, at 1:00 p.m. local time, at SunValley Banquet & Party Center, 10000 Edwards Lane, Aurora, Ohio, 44202. The accompanying Notice of Meeting and this Proxy Statement are first being mailed to shareholders on or about April 4, 2016.2019.

References in this proxy statement to “Middlefield,” “we,” “us,” and “our” mean Middlefield Banc Corp. alone or Middlefield Banc Corp. and its subsidiaries, depending on the context. The subsidiaries of Middlefield Banc Corp. are The Middlefield Banking Company and EMORECO, Inc.

GENERAL INFORMATION ABOUT THE ANNUAL MEETING

Purpose of the Meeting. At the annual meeting we will ask Middlefield shareholders (1) to elect four directors to serve until the 20192022 Annual Meeting of Shareholders or until their successors are elected and qualified, (2) to elect one director to serve until the 2018 Annual Meeting of Shareholders or until a successor is elected and qualified, (3) to act on anon-binding, advisory proposal to approve the named executive officer compensation disclosed in this proxy statement in accordance with SEC rules of the Securities and Exchange Commission (“SEC”), (3) to specify in anon-binding, advisory vote a preference for the frequency with which we submit to shareholders in the future thenon-binding, advisory proposal for approval of executive compensation, and (4) to ratify the appointment of Middlefield’s independent auditor. Thenon-binding proposal for approval of executive compensation is commonly known as asay-on-pay proposal.

Voting Procedures.If you were a shareholder at the close of business on March 21, 20162019, you are entitled to vote at the annual meeting. As of March 21, 20162019, there were 1,882,0263,256,370 shares of Middlefield common stock issued and outstanding.

The enclosed proxy is for use if you are unable to attend the annual meeting in person or if you wish to have your shares voted by proxy even if you attend the annual meeting. Regardless of whether you plan to attend the annual meeting, please vote your shares by (1) the Internet or (2) completing, signing, dating, and returning the enclosed proxy as soon as possible in the postage paid envelope provided. If you hold your shares in the name of a bank or broker, the availability of Internet voting will depend on the voting processes of the bank or broker.

Proxies solicited hereby may be used at the annual meeting only and will not be used for any other meeting. Proxies solicited by the board will be voted in accordance with the directions given. If no instructions are given, proxies will be voted in favor of the proposals set forth in this proxy statement.

Revocation of Proxies. Shareholders who execute proxies retain the right to revoke them at any time before completion of the annual meeting, but revocation will not affect a vote previously taken. If your common stock is held in street name, you must follow the instructions of your broker, bank, or other nominee to revoke your proxy instructions. If you are a holder of record and wish to revoke your proxy instructions, you may revoke a proxy by –

A written notice revoking a proxy should be delivered to Ms. Kathleen M. Johnson, Secretary,Mr. James R. Heslop, II, Executive Vice President and Chief Operating Officer, Middlefield Banc Corp., 15985 East High Street, P.O. Box 35, Middlefield, Ohio 44062. Unless revoked, the shares represented by proxies will be voted at the annual meeting.

Expense of Soliciting Proxies. Middlefield will bear the cost of soliciting proxies. We will reimburse brokerage firms and other custodians, nominees, and fiduciaries for reasonable expenses incurred by them in sending proxy material to the beneficial owners of common stock. In addition to solicitationssolicitation by mail, directors, officers, and regular employees of Middlefield and its subsidiaries may solicit proxies personally or by telephone, but they will receive no additional compensation for doing so.

Quorum and Vote Required. A quorum is necessary for the conduct of business at the annual meeting. When present in person or by proxy at the annual meeting, the holders of a majority of the shares of Middlefield common stock issued and outstanding and entitled to vote constitute a quorum.

Shareholders are entitled to one vote for each share held. Shareholders are not entitled to cumulate their votes in the election or removal of directors or otherwise. Directors are elected by a plurality vote of shareholders present in person or by proxy and constituting a quorum, meaning the nominees receiving the greatest numbers of votes will be elected. We will consider the say-on-paynon-binding proposal to approve the compensation of Middlefield Banc Corp.’s named executive officers(“say-on-pay”) to be approved if the proposal receives the affirmative vote of a majority of the votes cast. We will consider thesay-on-pay frequency alternative for future advisory votes concerningsay-on-pay proposals to be approved by a majority of the votes cast, or by a plurality if there is no clear majority. We will consider the proposal to ratify the appointment of S.R. Snodgrass, P.C. as independent auditor to be approved if the proposal receives the affirmative vote of a majority of the votes cast.

Abstentions and BrokerNon-Votes. Abstention may be specified on all proposals except the election of directors. A brokernon-vote arises when shares held by a broker nominee for a beneficial owner/customer are not voted because the broker nominee does not receive voting instructions from the customer and lacks discretionary authority to vote the shares without instructions. Brokers normally have authority to vote on routine matters, such as the ratification of independent registered public accounting firms, but not onnon-routine matters, such as amendments of charter documents, executive compensation proposals, and the election of directors. Pursuant to applicable stock exchange rules, the ratification of the appointment of Middlefield’s independent registered public accounting firm (Proposal 4) is the only routine matter. Our Regulations provide in Article I, section 7 that a majority of votes cast is sufficient to constitute the act of shareholders. Because abstentions and brokernon-votes are not counted as votes cast, they will have no impact on any of the proposals, although theyproposals. Abstentions and brokernon-votes will be counted for purposes of establishing that a quorum is present at the meeting.

Board Recommendations. The board of directors recommends that you voteFOR election of the director nominees identified in this proxy statement,FOR thesay-on-pay proposal,FOR“one year” as the preferred frequency of future advisory votes on the compensation of Middlefield Banc Corp.’s named executive officers, andFOR ratification of the appointment of S.R. Snodgrass, P.C. as auditor.auditor for the fiscal year ending December 31, 2019.

CORPORATE GOVERNANCE

Director Independence. A majority of Middlefield’s directors are independent, as the term independence is defined in Rule 5605(a)(2) of the NASDAQ Stock Market listing rules and as defined by Rule10A-3(b)(1)(ii) of the Securities and Exchange Commission.SEC. The board has determined that all of the current directors and director nominees other than Messrs. Caldwell and Heslop are independent directors, including all directors serving on the Corporate Governance and Nominating Committee, the Audit Committee, and the Compensation Committee.

Leadership Structure of the Board. The office of Chairman of the Board and the office of President and Chief Executive Officer have traditionally been separate at Middlefield. Middlefield believes that separation of these two offices is consistent with the board’s responsibility for oversight of management and of Middlefield’s affairs generally. The time, effort, and energy that the President and Chief Executive Officer and President must devote to that position, as well as the commitment required to serve as Chairman of the Board, make it impractical for one person to serve in both roles. The board believes that an independent director serving as Middlefield’s Chairman of the Board is the appropriate leadership structure at this time, demonstrating Middlefield’s commitment to good corporate governance.

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Risk Oversight. The board is actively involved in oversight of the risks that could affect Middlefield. The board’s oversight is conducted primarily through committees, but the full board retains responsibility for general oversight of risks. Board committees exercising oversight of risks include (1) an Audit Committee that takes into account financial reporting and legal and compliance risks, (2) a Compensation Committee that is responsible for risks relating to Middlefield’s employment policies and compensation and benefits systems, (3) a Corporate Governance and Nominating Committee that oversees risks relating to management and board succession planning and Middlefield’s ethics and business practices, and (4) other bank committees, such as the loan and asset/liability

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management committees, that are responsible for exercising oversight of the risks associated with the business of banking. The board satisfies its risk oversight responsibility through full reports by each committee chair regarding the committee’s considerations and actions, as well as through regular reports directly from officers responsible for oversight of particular risks within Middlefield, The Middlefield Banking Company, and EMORECO, Inc.

Code of Ethics. Our Code of Ethics requires that directors, executive officers, and employees avoid conflicts of interest, comply with all laws and other legal requirements, conduct business in an honest and ethical manner, and

otherwise act with integrity and in Middlefield’s best interests. Directors, executive officers, and employees must report any conduct they believe in good faith to be an actual or apparent violation of the Code of Ethics. Middlefield’s Code of Ethics includes a Code of Ethics for Financial Professionals, which applies to the principal executive officer, principal financial officer, principal accounting officer or controller, or personpersons performing similar functions. The goal of the Code of Ethics for Financial Professionals is to promote integrity in the preparation and reporting of financial information and to assure full, fair, accurate, timely, and understandable disclosure in SEC reports and other public communications. The Code of Ethics is available at www.middlefieldbank.com.www.middlefieldbank.bank.

Anti-Hedging Policy. Middlefield’s Insider Trading Policy prohibits hedging transactions involving Middlefield’s securities by directors, executive officers and employees of Middlefield or The Middlefield Banking Company. The anti-hedging policy: (i) requires that Middlefield securities purchased by a director, officer or employee in the open market must be held for a minimum of six months and preferably longer; (ii) prohibits direct and indirect short selling of Middlefield securities by directors, officers or employees; (iii) prohibits transactions by directors, officers or employees in puts, calls or other derivative transactions involving Middlefield’s securities, other than the exercise of options issued by Middlefield to its employees or directors; (iv) prohibits other forms of hedging or monetarization transactions by directors, officers or employees, such aszero-cost dollars and forward sales transactions, involving Middlefield’s securities; and (v) prohibits directors, officers or employees from holding Middlefield securities in a margin account or pledging Middlefield securities as collateral for a loan without first obtaining approval.

Shareholder Communications. A.A shareholder who wishes to communicate with the board or with individual directors concerning Middlefield’s financial statements, accounting practices, or internal controls should write to the chairman of the Audit Committee in care of Ms. Kathleen M. Johnson, Secretary,Mr. James R. Heslop, II, Executive Vice President and Chief Operating Officer, at Middlefield Banc Corp., 15985 East High Street, P.O. Box 35, Middlefield, Ohio 44062. If the shareholder’s concern relates to Middlefield’s governance practices, business ethics, or corporate conduct, the concern should be submitted in writing to the chairman of the Corporate Governance and Nominating Committee in care of Ms. Kathleen M. Johnson, Secretary,Mr. James R. Heslop, II, Executive Vice President and Chief Operating Officer, at the address above. Other concerns may be submitted to any of the independent directors in care of Ms. Kathleen M. Johnson at that address.

Board Meetings and Committees. Middlefield’s board held nineeight meetings in 2015. The individuals2018. Each individual who served in 20152018 as directorsa director of Middlefield attended at least 75% of the sum of the total number of board meetings and the total number of meetings held by all committees on which he or she served.served during the tenure of his or her service, with the exception of Mr. Valerian. The board encourages directors to attend the annual meeting of shareholders. OfAll of the tenincumbent directors who served in 2015, nineand director nominees attended the 2015 annual meeting.2018 Annual Meeting. Directors serving on the Corporate Governance and Nominating Committee, the Compensation Committee, and the Audit Committee are –

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Corporate Governance and Nominating Committee. The Corporate Governance and Nominating Committee recommends to the board the slate of director nominees to be proposed by the board for election by the shareholders, any director nominees to be elected by the board to fill interim director vacancies, and the directors to be selected for membership on and chairmanship of the committees of the board. In addition, the committee considers general corporate governance matters on behalf of the board and annually reviews with the board the requisite skills and criteria for new members. The committee also reviews the composition and function of the board as a whole. The committee met fivefour times in 2015.2018.

To identify nominees, the committee relies on personal contacts as well as its knowledge of members of the local communities. Middlefield has not previously used an independent search firm to identify nominees. The committee does not have a policy for the consideration of diversity in the nomination process, but the committee takes into account in its deliberations all facets of a potential nominee’s background, including the following –

the previous year’s annual meeting, and no more than 120 days before that date. A nomination made by a shareholder who does not comply with these procedures will be disregarded.

Middlefield’s Corporate Governance Guidelines provide that upon attaining age 75 a director may complete his or her term but may not stand for election to an additional term.

Compensation Committee. The Compensation Committee establishes the base salary of each executive officer as well asofficer. The Middlefield Banking Company’s Compensation Committee establishes the executives’ award levels under the Annual Incentive Plan.Plan and administers the executive deferred compensation agreements entered into by The committeeMiddlefield Banking Company. Middlefield’s Compensation Committee is also responsible for administration of other executive benefits and plans, including the 2007 Omnibus Equity Plan, and the executive deferred compensation agreements entered into by The Middlefield Banking Company.2017 Omnibus Equity Plan. The Compensation Committee’s performance review of the Chief Executive Officer takes into account reports submitted by each director. Performance reviews of other executives are the primary responsibility of the Chief Executive Officer. The Compensation Committee met fourthree times in 2015.2018. A copy of the Compensation Committee charter is available at www.middlefieldbank.com.www.middlefieldbank.bank. A copy of the charter is also available in print to shareholders upon request, addressed to Mr. James R. Heslop, II, Executive Vice President and Chief Operating Officer, at Middlefield Banc Corp., 15985 East High Street, P.O. Box 35, Middlefield, Ohio 44062.

The Compensation Committee has in the past sought input on both board and executive compensation issues from compensation consultants. The committee sometimes engages consultants to conduct periodic comprehensive total compensation studies or to advise about compensation practices generally. The Compensation Committee retains the right to hire, fire, and obtain advice and assistance from legal counsel or other experts or consultants, consistent with its charter. In 20142017, the Compensation Committee solicited proposals from compensation consultants for recommendations about equity compensation, both forselected Blanchard Consulting Group to review management and director compensation. Blanchard Consulting Group reviewed Middlefield’s compensation practices and provided surveys of the compensation practices in Middlefield’s peer group of financial institutions. In 2018, the Compensation Committee adopted several of Blanchard Consulting Group’s recommendations, including recommendations to increase the annual fee paid to the Chairman of the Board of Directors, to increase the base salaries of the President and Chief Executive Officer and of the Senior Vice President, Chief Financial Officer and Treasurer to bring those salaries in line with Middlefield’s peer group, and to establish new minimum, intermediate and maximum award levels under the annual short-term cash incentive plan for directors.named executive officers and selected senior officers.

Total compensation for the named executive officers is comprised of base salaries, annual cash incentive awards, retirement plan contributions, equity awards and other benefits and perquisites. To determine compensation levels for the named executive officers, as well as other officers, the Compensation Committee reviews compensation survey data from independent sources to ensure that the total compensation program is competitive. In making determinations on the mix and amount of executive compensation, the Compensation Committee reviews all components of executive compensation for each executive. The Compensation Committee ultimately selected Meyer-Chatfieldhas no mandatory policy for the allocation among base salary, short-term performance-based cash bonuses, long-term incentives, and retirement benefits. The Compensation AdvisorsCommittee considers Middlefield’s performance, industry comparative data, experience, tenure, and responsibilities in late 2014.recommending compensation for each position. Executive and officer compensation is weighted toward Middlefield’s performance and achievement of annual and long-term objectives. In early 2015 Meyer-Chatfield analyzed communitygeneral, Middlefield attempts to target total compensation for named executive officers at market competitive levels of peer financial companies.

The Compensation Committee and the compensation consultant evaluated Middlefield pay practices for the named executive officers with comparison to the following similarly situated banking organizations’ equity compensation practices and made recommendations for more closely aligning equity compensation practices with stockholder interests. Taking Meyer-Chatfield’s recommendations and analysis into account, we have implemented a change in our equity compensation practices, awarding restricted stock with vesting dependent not only on continued service over time but also on achieving an established average annual return on Middlefield stock.

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The peer group is made up of 25 banks with 2016-year end assets between $1.5 billion and $655.2 million. Each of the financial services institutions listed above are publicly traded institutions that ranged in size from approximately 190% of Middlefield’s asset level to approximately 83% of Middlefield’s asset level, and are located in Indiana, Kentucky, Michigan, Ohio, western Pennsylvania, and West Virginia.

Companies are included in Middlefield’s group based on their relevance in terms of asset size, business model, products, services and geographic location as compared to that of Middlefield.

Audit Committee. The Audit Committee appoints Middlefield’s independent public auditor, reviews and approves the audit plan and fee estimate of the independent public auditor, appraises the effectiveness of the internal and external audit efforts, evaluates the adequacy and effectiveness of accounting policies and financial and accounting management, supervises the internal auditor, and reviews and approves the annual financial statements. The Audit Committee has the authority to engage separate legal counsel and other advisors, as necessary, to execute its duties. The Audit Committee met sixfour times in 2015.2018. A copy of the Audit Committee charter is available at www.middlefieldbank.com.www.middlefieldbank.bank. A copy of the charter is also available in print to shareholders upon request, addressed to Mr. James R. Heslop, II, Executive Vice President and Chief Operating Officer, at Middlefield Banc Corp., 15985 East High Street, P.O. Box 35, Middlefield, Ohio 44062.

Middlefield believes that the directors serving on the Audit Committee do not have a relationship with Middlefield or its subsidiaries that would interfere with the exercise of independent judgment as directors. The board believes that all members of the Audit Committee satisfy the current independence requirements of the NASDAQ Stock Market and applicable rules and regulations of the SEC, and that Director Jones and Director Turk are audit committee financial experts, as that term is defined in SEC rules.

Audit Committee Report. The Audit Committee reviewed and discussed the audited financial statements for the year ended December 31, 2015,2018 and discussed the audited financial statements with management. The Audit Committee has also discussed with S.R. Snodgrass, P.C., Middlefield’s independent auditor, the matters required to be discussed by PCAOB AU Section 380Auditing Standard No. 16 (Communication with Audit Committees). The Audit Committee received the written disclosures and the letter from S.R. Snodgrass, P.C. required by Independence Standards Board Standard No. 1 (Independence Discussion with Audit Committees), and discussed with S.R. Snodgrass, P.C. its independence. Based on this, the Audit Committee recommended to the board that the audited financial statements be included in Middlefield’s Annual Report on Form10-K for the fiscal year ended December 31, 20152018 for filing with the Securities and Exchange Commission.SEC.

Submitted by the Audit Committee:

Kenneth E. Jones, Darryl E. Mast, James J. McCaskey,Clayton W. Rose, III, Robert W. Toth, and Carolyn J. Turk, C.P.A.Turk.

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DIRECTOR COMPENSATION

The following table shows the compensation paid to nonemployee directors for their service in 2015,2018, including their service on our board, on the board of The Middlefield Banking Company, and on the board committees of Middlefield and The Middlefield Banking Company. The compensation of Directors Caldwell and Heslop is included in the Summary Compensation Table.

Director Fees. Middlefield directors receive compensation of $750 for each board and committee meeting attended. Middlefield’s Chairman of the Board receives additional annual compensation of $4,000.$10,000. The Chairmen of Middlefield’s Audit Committee and Compensation Committee each receive additional annual compensation of $3,000 and the Chairmen of Middlefield’s Corporate Governance and Nominating Committee and Executive Committee each receive additional annual compensation of $2,000. The Middlefield Banking Company directors receive compensation of approximately $1,800 per month, less $100 for each meeting not attended inconsisting of a particular month.monthly cash retainer of $1,000, and a grant of Middlefield stock with an approximate value of $9,600. The directors receive the stock grant, which vests immediately, as near to January 1 as possible and is calculated based upon the closing price on the last trading day of the previous year. The Middlefield Banking Company directors also receive $500 in committee fees for each meeting attended. The 2015Chairmen of The Middlefield Banking Company’s Asset Liability Committee and Risk/Compliance Committee each receive additional annual compensation of $2,000. The 2018 compensation of Director Jones and Director Rose includes $2,700$3,300 and $3,000, respectively, for histheir service on our Central Ohio Regional Advisory Board. Directors of EMORECO, Inc. receive no compensation for board service.

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Director Indemnification. At the 2001 annual meeting shareholders approved the form and use of indemnification agreements for directors. The indemnification agreements allow directors to select the most favorable indemnification rights provided under (1) Middlefield’s Second Amended and Restated Articles of Incorporation or Regulations in effect on the date of the indemnification agreement or on the date expenses are incurred, (2) state law in effect on the date of the indemnification agreement or on the date expenses are incurred, (3) any liability insurance policy in effect when a claim is made against the director or on the date expenses are incurred, and (4) any other indemnification arrangement otherwise available. The agreements cover all fees, expenses, judgments, fines, penalties, and settlement amounts paid in any matter relating to the director’s role as a Middlefield director, officer, employee, agent, or when serving as Middlefield’s representative with respect to another entity. Each indemnification agreement provides for the prompt advancement of all expenses incurred in connection with any proceeding subject to the director’s obligation to repay those advances if it is determined later that the director is not entitled to indemnification.

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VOTING SECURITIES AND PRINCIPAL HOLDERS

The following table shows the beneficial ownership of Middlefield common stock on March 21, 20162019 on the part of each director, each director nominee, each executive officer identified in the Summary Compensation Table, and all directors, nominees, and executive officers as a group. For purposes of the table, a person is considered to own beneficially any shares over which he or she exercises sole or shared voting or investment power or of which he or she has the right to acquire beneficial ownership within 60 days. Unless noted otherwise, voting power and investment power are exercised solely by the person named or they are shared with members of his or her household. The percentage figures are based on 1,882,0263,256,370 shares outstanding, plus the number of shares each individual has the right to acquire within 60 days.

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Director Stock Ownership Guidelines. Middlefield’s Corporate Governance Guidelines include stock ownership guidelines for directors. The guidelines state that within three years after election a director should own Middlefield common stock equal in value to at least two times the director’s yearly base compensation for service as a director of The Middlefield Banking Company, and three times base compensation within six years. As of December 31, 2015, the projected annual yearly compensation of a director other than the Chairman2018, all of the Board is $21,600.directors met the stock ownership guidelines. While Middlefield encourages ownership of Middlefield stock by all executive officers, Middlefield has not adopted a stock ownership requirement for

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Middlefield’s named executive officers. As of December 31, 2018, ownership of Middlefield common stock, which includes thein-the-money value of stock options, for Middlefield’s named executive officers equaled in value for Mr. Caldwell more than two times Mr. Caldwell’s base salary, for Mr. Heslop, approximately two times Mr. Heslop’s base salary, and for Mr. Stacy, approximately one times Mr. Stacy’s base salary.

Section 16(a) Beneficial Ownership Reporting Compliance. Section 16(a) of the Securities Exchange Act of 1934 requires that directors and executive officers, as well as any persons who own more than 10% of a registered class of equity securities, file with the SEC initial reports of ownership and reports of changes in ownership. Based solely on review of the copies of such reports furnished to Middlefield and written representations to Middlefield, to Middlefield’s knowledge all section 16(a) filing requirements applicable to its executive officers, directors, and greater than 10% beneficial owners were complied with during the fiscal year ended December 31, 2015,2018, except that (i) Directors Caldwell, Heslop, Hummel, Jones, Mast, McCaskey, Rose, Skidmore, Toth and Turk each filed late one Form 4 relating to a stock award granted to directors of The Middlefield Banking Company; (ii) Director MastWilliam A. Valerian filed late one Form 4 relating to a stock sale; and (iii) executive officers Dalessandro, Erminio, Hollinger,Allen and MaleLane have not filed a Form 3.

SUMMARY COMPENSATION TABLE

The majority of the compensation of executive officers is paid by The Middlefield Banking Company, but compensation shown in the table is aggregate compensation paid by Middlefield and The Middlefield Banking Company, and Emerald Bank.Company. No compensation is paid by EMORECO, Inc. Emerald Bank merged into The Middlefield Banking Company on January 20, 2014.

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Perquisites and other personal benefits provided to each of the named executive officers in 20152018 and 20142017 had a value of less than $10,000. The value of insurance on the lives of the named executive officers is not included in the Summary Compensation Table because the executives have no interest in the policies. However, the executives are entitled to designate the beneficiary of death benefits payable by The Middlefield Banking Company under executive survivor income agreements. See the “Executive Survivor Income Agreements” discussion below.section.

Annual Incentive Plan. In 2003, The Middlefield Banking Company established the Annual Incentive Plan, a short-term cash incentive plan that rewards employees with additional cash compensation if specific objectives are achieved. An employee’s potential cash incentive payment under the Annual Incentive Plan depends upon two factors: (x) the employee’s position, which establishes a maximum cash incentive award as a percent of base salary, and (y) the degree to which the performance targets, such as targeted net income, and individual performance targets, are achieved. Annual incentive payments under the plan for a particular year generally are based on objective financial performance criteria established by theThe Middlefield Banking Company board, with the Compensation Committee’s recommendation. A copy of the plan is included as exhibit 10.22 to the Form 8-K Current Report that we filed with the SEC on June 12, 2012, which is available for viewing or download at www.sec.gov. All employees are eligible for awards under the Annual Incentive Plan. The plan is terminable by the board at any time.

The bank-wide performance objectives that had to be achieved in 20152018 in order for Messrs. Caldwell, Heslop, and Stacy to receive a cash incentive payment under the plan included a net income goal, a goal for reduction of adversely classified loans as a percent of the sum of tier 1 capital and the allowance for loan and lease losses, a goal for loan growth, and a goal having to do with the regulatory and supervisory status of Middlefield and The Middlefield Banking Company.Company, and a goal for deposit growth. Please see the Form8-K Current Report filed by Middlefield with the SEC on June 18, 2015March 13, 2018 for additional information. In future years other financial performance measures could be taken into account, such as return on average equity (ROAE), return on average assets (ROAA), deposit growth, and net interest margin. The bank’s Compensation Committee also considers individual performance goals.

The Annual Incentive Plan was amended and restated effective March 11, 2019. A copy of the plan is included as exhibit 10.22 to the Form8-K Current Report that we filed with the SEC on March 12, 2019, which is available for viewing or download at www.sec.gov. All employees are eligible for awards under the Annual Incentive Plan. The plan is terminable by the board at any time.    As amended, the Annual Incentive Plan provides that Mr. Caldwell is

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eligible for a cash bonus in an amount ranging from a minimum of 12% of his salary if actual performance is 90% of targeted performance goals established by the bank’s Compensation Committee, 24% of salary if actual performance is 100% of targeted performance goals, and a maximum of 36% of salary if actual performance is 110% or more of targeted performance goals. Mr. Caldwell’s annual award under the plan is exclusively determined by the bank’s performance. Mr. Heslop and Mr. Stacy are eligible for cash bonuses in an amount ranging from a minimum of 12% of salary if actual performance is 90% of targeted performance goals, 18% of salary if actual performance is 100% of targeted performance goals, and a maximum of 24% of salary if actual performance is 110% or more of targeted performance goals. Messrs. Heslop and Stacy’s annual award under the plan is exclusively determined by the bank’s performance.

The Annual Incentive Plan has certain forfeiture and recoupment, or “clawback,” provisions that allow the board to rescind awards under the plan that have not yet been paid, and recover awards that have been paid, upon the occurrence of certain events. The Compensation Committee may rescind and not pay an incentive award to a participant in the Annual Incentive Plan if the Compensation Committee finds that the participant failed significantly to satisfy expectations, engaged in fraudulent or unethical conduct in the course of the participant’s employment or committed an intentional violation of bank policy. The Annual Incentive Plan also provides that a participant in the plan agrees to repay to The Middlefield Banking Company any award that is entirely or partially attributable to a financial reporting error. If an award is entirely attributable to a financial reporting error, the participant must promptly repay to The Middlefield Banking Company the entire amount of the award and if an award is partially attributable to a financial reporting error the participant must promptly repay to The Middlefield Banking Company the portion of the award that the Compensation Committee determines is attributable to the financial reporting error.

20072017 Omnibus Equity Plan. On May 10, 2017, shareholders approved the 2017 Omnibus Equity Plan. No further equity awards will be made under the 2007 Omnibus Equity Plan; however, awards previously granted and outstanding under the 2007 Omnibus Equity Plan remain in effect.

The 20072017 Omnibus Equity Plan authorizes the issuance of 160,000224,000 shares of Middlefield common stock. Middlefield’s Compensation Committee administers the Omnibus Equity Plan. Shares of common stock issued under the Omnibus Equity Plan may be treasury shares, authorized and unissued shares not reserved for any other purpose, or a combination of treasury shares and authorized but unissued shares. Awards to employees may take the form of incentive stock options, orISOs, that qualify for favored tax treatment under Internal Revenue Code section 422, stock options that do not qualify under section 422, referred to asNQSOs, stock appreciation rights, orSARs, restricted stock, restricted stock units, performance shares, which become fully vested if conditions imposed in the award agreement are satisfied, and performance shares.other stock-based awards. In contrast to the kinds of awards that may be

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made to employees,non-employee directors are eligible for awards of NQSOs, and restricted stock, only.restricted stock units and other stock-based awards. The terms of each award are stated in award agreements. Of the shares authorized for issuance under the Omnibus Equity Plan, up to one half, or 112,000 shares, may be reserved for issuance under incentive stock options. The aggregate number of shares underlying awards granted to an individual participant in a single year may not exceed 16,000.22,400.

Unless the participant’s award agreement provides otherwise, when a participant employee’s serviceemployment terminates or when anon-employee director participant’s service terminates, the portion of any award held by the participant that is not exercisable is forfeited and the portion of any restricted stock award or performance share award that is unvested and held in escrow is forfeited. All NQSOs, SARs, ISOs and ISOsother stock-based awards held by the participant that are exercisable are forfeited if not exercised before the earlier of the expiration date specified in the award agreement or 90 days after termination occurs. However, all of a participant’s outstanding awards are forfeited if the participant’s employment or director service terminates for cause or if in Middlefield’s judgment a basis for termination for cause exists, regardless of whether the awards are exercisable and regardless of whether the participant’s employment or director service actually terminates. However, shares of restricted stock or performance shares that have been released from escrow and distributed to the participant are not affected by a termination for cause.

If a change in control of Middlefield occurs, the Compensation Committee has broad authority and sole discretion to take actions it deems appropriate to preserve the value of participants’ awards. In general, a change in control means one or more of the following events occur –

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To align equity compensation practices with stockholder interests, in 2015 we implemented a change in our equity compensation practices, awarding restricted stock with vesting that is typically dependent not only on continued service over time but also on achieving an established average annual return on Middlefield stock.

Executive Deferred Compensation Agreements. The Middlefield Banking Company entered into executive variable benefit deferred compensation agreements with Messrs. Heslop and Stacy on July 9, 2018. Under the executive variable benefit deferred compensation agreements, the executives will receive an annual contribution ranging from 5% to 15% of their base salary. Contributions exceeding 5% of salary are conditional on achievement of performance goals involving (i) the bank’s net income for the plan year and (ii) the bank’s peer ranking for the plan year based on the top 50% of all FDIC-insured commercial banks having assets between $1 billion and $3 billion as reported on the Uniform Bank Performance Report (“UBPR”) as reported on the Federal Financial Institutions Examination Council’s website at www.ffiec.gov/UBPR.htm. The UBPR is an analytical tool created for bank supervisory, examination, and management purposes. In a concise format, the UBPR shows the impact of management decisions and economic conditions on a bank’s performance and balance-sheet composition. The executive variable benefit deferred compensation agreements do not supersede the May 8, 2008 amended executive deferred compensation agreements to which Messrs. Heslop and Stacy are parties.

The Middlefield Banking Company entered into executive deferred compensation agreements with Messrs. Caldwell, Heslop, and Stacy on December 28, 2006. Amended on May 9, 2008 for compliance with Internal Revenue Code section 409A, the executive deferred compensation agreements provide supplemental retirement income benefits. The arrangement is noncontributory, meaning contributions can be made solely by The Middlefield Banking Company. For each year the executive remains employed with The Middlefield Banking Company, until attaining age 65 Thethe Middlefield Banking Company may creditcredits each executive with a contribution equalranging from 5% to 5%15% of the executive’s base annual salary. Messrs. Heslop and Stacy’s contributions ended after the executives reached age 65 during the fourth quarter of 2018. Messrs. Heslop and Stacy’s payments began after the executives reached aged 65. Contributions exceeding 5% of salary are conditional on achievement of performance goals:goals involving: (x) The Middlefield Banking Company’s net income for the plan year and (y) The Middlefield Banking Company’s peer ranking for the plan year, based on the Uniform Bank Performance Report availabletop 50% of all FDIC-insured commercial banks having assets between $1 billion and $3 billion as reported on the UBPR as reported on the Federal Financial Institutions Examination Council’s website at www.ffiec.gov/UBPR.htm. The UBPR is an analytical tool created for bank supervisory, examination, and management purposes. In a concise format, the UPBR shows the impact of management decisions and economic conditions on a bank’s performance and balance-sheet composition.

Each of the two performance goals can account for a contribution of up to 7.5% of the executive’s base annual salary. The net income goal for each year is established by theThe Middlefield Banking Company’s Compensation Committee by March 31 of that year. The Compensation Committee’s decisions are not final unless approved by a majority of Middlefield’sthe independent directors.

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Executive Survivor Income Agreements. The Middlefield Banking Company entered into executive survivor income agreements with executives in June 2003, including Messrs. Caldwell, Heslop, and Stacy. The agreements promise a specific cash benefit payable by The Middlefield Banking Company to an executive’s designated beneficiary at the executive’s death, provided the executive dies before attaining age 85. The benefit would be paid to the executive’s beneficiary if the executive dies in active service to The Middlefield Banking Company, but it also would be payable for death occurring after the executive’s termination of service if the executive terminated (x) because of disability, or (y) within 12 months after a change in control of Middlefield, or (z) after having attained age 55 with at least ten years of service to The Middlefield Banking Company or after having attained age 65.

The total death benefit payable to Mr. Caldwell’s beneficiaries if he dies in active service to The Middlefield Banking Company is $471,741, the benefit payable to Mr. Heslop’s beneficiaries is $368,970, and the benefit payable to Mr. Stacy’s beneficiaries is $222,619. For death after terminating active service with The Middlefield Banking Company, the death benefit for Mr. Caldwell’s beneficiaries is $471,741, $368,970 for Mr. Heslop’s beneficiaries, and $111,309 for Mr. Stacy’s beneficiaries. To assure itself of funds sufficient to pay the promised death benefits, The Middlefield Banking Company purchased insurance on the executives’ lives with a single premium payment. The Middlefield Banking Company owns the policies and is the sole beneficiary. Of the total premium paid for the insurance on the various executives’ lives, $495,873 is attributable to insurance purchased on the life of Mr. Caldwell, $447,351 is attributable to insurance on the life of Mr. Heslop, and $333,890 is attributable to insurance purchased on the life of Mr. Stacy. The premium amounts are not included in the Summary Compensation Table. The Middlefield Banking Company expects the policies’ death benefits to be sufficient to pay all benefits promised under the executive survivor income agreements.

SeveranceChange-in-Control Agreements. Middlefield and its subsidiaries do not have written employment agreements with officers, although Middlefield entered into severance agreements with executives, including Messrs. Caldwell, Heslop, and Stacy. The severance agreements provide that the executive is entitled to severance compensation if a change in control occurs during the term of the agreement. The severance compensation is payable in a single lump sum. For purposes of the severance agreements, the term change“change in controlcontrol” is defined as it is defined in Internal Revenue Code section 409A and implementing rules. In the case of executives other than Messrs. Caldwell, Heslop, and Stacy, thelump-sum severance benefit is payable immediately after involuntary termination without cause or voluntary termination with good reason occurring within 24 months after a change in control. Rather than being contingent on a separation from service after a change in control, the Thelump-sum benefit of Messrs. Caldwell, Heslop, and Stacy is payable immediately afterwhen a change in control occurs.

The agreements promise to each executive alump-sum payment calculated as a multiple of the executive’s salary and the executive’s cash bonus and cash incentive compensation. The multiple of compensation payable under the severance agreements is 2.5 times in the case of Mr.Messrs. Caldwell, Heslop and Mr. HeslopStacy and two times compensation for other executives. The agreements also promise continued life, health, and disability insurance coverage for 24 months after employment termination and legal fee reimbursement if the severance agreements are challenged after a change in control. Thechange-in-control agreements with Messrs. Caldwell, Heslop and Stacy are included in the Form8-K Current Report filed by Middlefield with the SEC on March 12, 2019.

Retirement Plan. Middlefield does not maintain a defined benefit or actuarial plan providing retirement benefits for officers or employees based on actual or average final compensation. But The Middlefield Banking Company maintains a section 401(k) employee savings and investment plan for substantially all employees and officers who have more than one year of service. The bank’s contribution to the plan is based on 50% matching of voluntary contributions, up to 6% of compensation. An eligible employee may contribute up to 15% of his or her salary. Employee contributions are vested at all times. Bank contributions are fully vested after six years, vesting in 20% annual increments beginning with the second year. Employees also have life insurance benefits under a group term life insurance program, paying benefits to an employee’s beneficiary if the employee dies while employed by The Middlefield Banking Company, up to the lesser of (x) twice the employee’s annual salary at the time of death or (y) $200,000.

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Internal Revenue Code Limits. The qualifying compensation regulations issued by the Internal Revenue Service under Internal Revenue Code section 162(m) state that no deduction is allowed for applicable employee remuneration paid by a publicly held corporation to a covered employee to the extent that the remuneration exceeds $1

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million for the applicable taxable year, unless specified conditions are satisfied. Salary and bonus amounts deferred by executives are not subject to section 162(m). Currently, Middlefield’s remuneration is not expected to exceed $1 million for any employee. Therefore, Middlefield does not expect that compensation will be affected by the qualifying compensation regulations. The Compensation Committee and Middlefield’s board intend to maintain executive compensation within the section 162(m) deductibility limits, but could permit compensation exceeding the section 162(m) limits in the future.

Transactions with Related Parties. Middlefield directors and executive officers and their associates are customers of and enter into banking transactions with The Middlefield Banking Company in the ordinary course of business. Middlefield expects that these relationships and transactions will continue. The transactions with directors, executive officers, and their associates have not involved more than the normal risk of collectability and have not presented other unfavorable features. Loans and commitments to lend included in these transactions were made and will be made on substantially the same terms – including interest rates and collateral – as those prevailing at the time for comparable transactions with persons not affiliated with Middlefield.

OUTSTANDING EQUITY AWARDS

The following table shows as of December 31, 20152018 unvested and unearned stock awards and the number of shares acquirable, exercise prices, and expiration dates of all unexercised stock options held by the executives identified in the Summary Compensation Table.

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PROPOSAL ONE – ELECTION OF FOUR DIRECTORS FOR THE TERM EXPIRING IN 2019

AND

PROPOSAL TWO – ELECTION OF A DIRECTOR FOR THE TERM EXPIRING IN 20182022

According to articleArticle III, section 2, of Middlefield’s regulations,Regulations, the board may consist of no fewer than five and no more than 25 directors, the precise number being fixed or changed from time to time within that range by the board or by majority vote of shareholders acting at an annual meeting. Article III, section 2(b) of Middlefield’s regulationsRegulations provides that if the number of directors (including vacancies) of Middlefield is six or more, the directors must be classified into at least two classes, as nearly equal in number as possible and consisting of no fewer than three directors in each class, designated Class I, Class II, and if there are nine or more directors, Class III. Our board currently consists of ten directors, although one of those director positions has become vacant with the resignation of Director Thomas.twelve directors. Class I of Middlefield’s board consists of Directors Hummel, Jones, McCaskey and McCaskeyValerian (term expiring at the 20172020 annual meeting), Class II includes Directors Bevan, Heslop, Rose, and Toth (term expiring at the 20182021 annual meeting), and Class III consists of Directors Caldwell, Mast, Skidmore, and Turk (term expiring at the 20162019 annual meeting). Mr. Joseph J. Thomas, a Class II director, notified Middlefield on February 24, 2016 of his resignation as a director, effective March 31, 2016. Clayton W. Rose III is

Four Nominees for the nominee to fillterm ending at the vacancy created by the resignation of Director Thomas.

Nominees2022 annual meeting (Proposal One).. The Corporate Governance and Nominating Committee recommended Directors Caldwell, Mast, Skidmore and Turk for reelection to the board. The board accepted the Corporate Governance and Nominating Committee’s recommendation and nominated these four individuals to serve as directors for the term ending at the 20192022 Annual Meeting of Shareholders or until their successors are elected and qualified. The Corporate Governance and Nominating Committee recommended and the board nominated Clayton W. Rose III for election to the term expiring at the 2018 Annual Meeting of Shareholders or until a successor is elected and qualified.