[425] MIDDLEFIELD BANC CORP Business Combination Communication

Rhea-AI Filing Summary

Middlefield Banc Corp. (MBCN) announced it entered into an Agreement and Plan of Merger with Farmers National Banc Corp., under which Middlefield will merge into Farmers. The disclosure was made on October 22, 2025 and includes a joint press release and investor presentation furnished as Exhibits 99.1 and 99.2.

Farmers expects to file a Form S-4 to register the Farmers common stock to be issued to Middlefield shareholders, with a joint proxy statement/prospectus to seek shareholder approvals. The transaction remains subject to regulatory and shareholder approvals and other customary closing conditions.

Insights

Bank M&A analyst

Announced bank merger; stock issuance via S-4 and shareholder votes.

Middlefield Banc Corp. agreed to merge into Farmers National Banc Corp.. The filing states Farmers will register shares on Form S-4 for issuance to Middlefield shareholders, indicating equity consideration. A joint proxy statement/prospectus will be used to solicit approvals from both companies’ shareholders.

Completion is conditioned on regulatory and shareholder approvals and customary closing conditions. The filing highlights integration and timing risks, including potential delays in approvals and execution risks during integration.

Key items to track include the effectiveness of the S-4 and the shareholder meetings for approval. Specific financial terms were not included in the provided excerpt; subsequent filings may detail the exchange mechanics.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

October 22, 2025

(Date of Report: Date of earliest event reported)

Middlefield Banc Corp.

(Exact name of registrant as specified in its charter)

Ohio

(State or other jurisdiction of incorporation)

001-36613

(Commission File Number)

34-1585111

(I.R.S. Employer Identification Number)

15985 East High Street

Middlefield, Ohio 44062

(Address of principal executive offices, including zip code)

(440) 632-1666

(Registrant’s telephone number, including area code)

(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:

☒ 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))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

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. ☐

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

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

ITEM 8.01  OTHER EVENTS

On October 22, 2025, Middlefield Banc Corp. (the “Company”) issued a joint press release announcing that it had entered into an Agreement and Plan of Merger with Farmers National Banc Corp., an Ohio corporation and bank holding company (“Farmers”) providing for, among other things, the merger of the Company with and into Farmers (the “Merger”). A copy of the joint press release, as well as a copy of the accompanying investor presentation, are furnished as Exhibit 99.1 and Exhibit 99.2 hereto, respectively, and incorporated herein by reference.

Forward-Looking Statements

This current report on Form 8-K contains “forward-looking statements” within the meaning of the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. These forward-looking statements are not statements of historical fact, but rather statements based on the Company’s current expectations, beliefs and assumptions regarding the future of the Company’s business, future plans and strategies, projections, anticipated events and trends, its intended results and future performance, the economy and other future conditions. Forward-looking statements are preceded by terms such as “will,” “would,” “should,” “could,” “may,” “expect,” “estimate,” “believe,” “anticipate,” “intend,” “plan” “project,” or variations of these words, or similar expressions.

Forward-looking statements are not a guarantee of future performance and actual future results could differ materially from those contained in forward-looking information. Because forward-looking statements relate to the future, they are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict and many of which are outside of the Company’s control. Numerous uncertainties, risks, and changes could cause or contribute to the Company’s actual results, performance, and achievements to be materially different from those expressed or implied by the forward-looking statements. Factors that may cause or contribute to these differences include, without limitation, risks that the proposed merger transaction will not close when expected or at all because required regulatory, shareholder or other approvals or conditions to closing are delayed or not received or satisfied on a timely basis or at all; risks that the benefits from the transaction may not be fully realized or may take longer to realize than expected, including as a result of changes in general economic and market conditions, interest and exchange rates, monetary policy, laws and regulations and their enforcement, and the degree of competition in the geographic and business areas in which the Company and Farmers operate; uncertainties regarding the ability of Farmers to promptly and effectively integrate the Company with its businesses in accordance with expectations; changes in business and operational strategies that may occur between signing and closing; uncertainties regarding the reaction to the transaction of the companies’ respective customers, employees, and contractual counterparties; and risks relating to the diversion of management time on merger-related issues; and other factors disclosed periodically in the Company’s filings with the Securities and Exchange Commission (“SEC”).

Because of the risks and uncertainties inherent in forward-looking statements, readers are cautioned not to place undue reliance on them, whether included in this report or made elsewhere from time to time by the Company or Farmers or on the Company or Farmer’s behalf. The Company and Farmers disclaim any obligation and do not intend to update or revise any forward-looking statements contained in this communication, which speak only as of the date hereof, whether as a result of new information, future events or otherwise, except as required by federal securities laws.

Additional factors which could affect future results of the Company can be found in the Company’s Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, and the Current Reports on Form 8-K, in each case filed with the SEC and available on the SEC’s website at https://www.sec.gov.

Information about the Merger and Where to Find It

In connection with the proposed Merger, Farmers expects to file a registration statement on Form S-4 with the SEC to register the shares of Farmers’ common stock that will be issued to the Company’s shareholders in connection with the Merger (the “Registration Statement”). The Registration Statement will include a joint proxy statement of the Company and Farmers that also constitutes a prospectus of Farmers. When available, the definitive joint proxy statement will be sent to the shareholders of Farmers and the Company seeking their approval of the proposed Merger. This communication is not a substitute for the joint proxy statement/prospectus or Registration Statement or for any other document that the Company or Farmers may file with the SEC and send to the Company’s shareholders in connection with the proposed merger transaction.

INVESTORS AND SECURITY HOLDERS ARE URGED TO CAREFULLY READ THE REGISTRATION STATEMENT AND ACCOMPANYING JOINT PROXY STATEMENT/PROSPECTUS REGARDING THE PROPOSED MERGER TRANSACTION WHEN IT BECOMES AVAILABLE ANDANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THOSE DOCUMENTS, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION.

Investors and security holders will be able to obtain free copies of the Registration Statement on Form S-4 (when available) and other documents containing information about the Company, Farmers, and the proposed merger transaction filed with the SEC through the website maintained by the SEC at http://www.sec.gov. Copies of the documents filed with the SEC by the Company will be available free of charge on the Company’s website at https://www.middlefieldbank.com or may be obtained from the Company by written request to Middlefield Banc Corp., 15985 East High Street, Middlefield, Ohio 44062, Attention: Investor Relations. Copies of the documents filed with the SEC by Farmers will be available free of charge on Farmers’ website at https://www.farmersbankgroup.com or may be obtained from Farmers by written request to Farmers National Banc Corp., 20 South Broad Street, Canfield, Ohio 44406, Attention: Investor Relations.

Participants in the Solicitation

The respective directors and executive officers of the Company and Farmers and other persons may be deemed to be participants in the solicitation of proxies from Farmers shareholders and Company shareholders with respect to the Merger. Information regarding the directors and executive officers of the Company is available in its proxy statement filed with the SEC on April 4, 2025. Information regarding the directors and executive officers of Farmers, is set forth in the proxy statement for Farmers’ 2025 annual meeting of shareholders, as filed with the SEC on March 18, 2025. Additional information regarding the interests of those participants and other persons who may be deemed participants may be obtained by reading the joint proxy statement/prospectus included in the Registration Statement and other relevant documents regarding the proposed merger transaction filed with the SEC when they become available. Copies of these documents may be obtained free of charge from the sources described above.

No Offer or Solicitation

This communication shall not constitute an offer to sell or the solicitation of an offer to buy any securities nor shall there be any sale of securities in any jurisdiction in which the offer, solicitation or sale is unlawful before registration or qualification of the securities under the securities laws of the jurisdiction. No offer of securities shall be made except by means of a prospectus satisfying the requirements of Section 10 of the Securities Act of 1933, as amended, and otherwise in accordance with applicable law.

ITEM 9.01 FINANCIAL STATEMENTS AND EXHIBITS

The following exhibits are furnished to this Current Report on Form 8-K:

(d) Exhibits.

	99.1	Joint Press Release dated October 22, 2025
	99.2	Investor Presentation dated October 22, 2025

104 Cover Page Interactive File (embedded within the Inline XBRL document)

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 hereunto duly authorized.

	MIDDLEFIELD BANC CORP.
Date: October 22, 2025	/s/ Ronald L. Zimmerly, Jr
	President and Chief Executive Officer

FAQ

What did Middlefield Banc Corp. (MBCN) announce in its Form 8-K?

Middlefield disclosed it entered into a merger agreement with Farmers National Banc Corp. under which Middlefield will merge into Farmers.

What filings will be prepared for the MBCN–Farmers merger?

Farmers expects to file a Form S-4 registering Farmers shares to be issued, including a joint proxy statement/prospectus for shareholder approvals.

What approvals are required for the MBCN merger?

The transaction is subject to regulatory and shareholder approvals and other customary closing conditions.

Where can investors find documents related to the merger?

Free copies will be available on the SEC’s website and on the investor relations pages of Middlefield and Farmers.

What exhibits accompanied the MBCN 8-K announcement?

A joint press release (Exhibit 99.1) and an investor presentation (Exhibit 99.2).

Will Middlefield shareholders receive stock from Farmers?

Yes. Farmers plans to register its common stock on Form S-4 for issuance to Middlefield shareholders in connection with the merger.