MIDDLEFIELD BANC CORP false 0000836147 0000836147 2025-06-02 2025-06-02

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): June 2, 2025

MIDDLEFIELD BANC CORP.

(Exact name of registrant as specified in its charter)

Ohio |  | 001-36613 |  | 34-1585111
(State or other jurisdiction of incorporation) |  | (Commission File No.) |  | (IRS Employer I.D. No.)

15985 East High Street, Middlefield, Ohio 44062
(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (440) 632-1666

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐ | Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ | Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ | Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ | Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class |  | Trading Symbol |  | Name of each exchange on which registered
Common Stock, no par value |  | MBCN |  | The NASDAQ Stock Market, LLC (NASDAQ Capital Market)

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 7.01 Other Events.

Middlefield Banc Corp. (NASDAQ: MBCN) intends to use the materials furnished herewith in one or more meetings with investors/analysts during the second quarter of 2025.

The information in this current Report on Form 8-K is being furnished under item 7.01 and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934 (the “Exchange Act”), nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

Item 9.01(d) Exhibits

The following exhibit is furnished as Regulation FD Disclosure to this Current Report on Form 8-K.

(a) Exhibits.

99.1 |  | 2025 First Quarter Investor Presentation
104 |  | Cover Page Interactive File (embedded within the Inline XBRL document)

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

MIDDLEFIELD BANC CORP.
By: |  | /s/ Ronald L. Zimmerly, Jr.
|  | Ronald L. Zimmerly, Jr.
|  | Chief Executive Officer
Date: |  | June 2, 2025