[Form 4] Middlefield Banc Corp. Insider Trading Activity

Rhea-AI Filing Summary

Middlefield Banc Corp. (MBCN) – Form 4 (08/06/25): CEO & Director Ronald L. Zimmerly Jr. reported routine equity transactions tied to previously granted restricted stock.

• Direct common-stock activity: 2,260 restricted shares vested (Code A) at $27.11; 663 shares were withheld for taxes (Code F), producing a net increase of 1,597 shares.
• Post-transaction direct ownership: 35,840.283 shares.
• Indirect holdings: 8,786 shares held in an IRA.
• Outstanding equity awards: 18,894 restricted stock units across four grants with scheduled vesting between Dec-2025 and Jan-2028 (largest grant = 6,864 RSUs granted 01/14/25).
• All awards confer no voting or dividend rights until vested; full vesting requires continued employment and, for some grants, the achievement of performance targets as disclosed in prior 8-K filings.

No cash was exchanged by the issuer; transactions reflect share delivery and tax withholding only. The filing signals continued insider equity accumulation and alignment but does not by itself alter Middlefield’s operating or financial outlook.

Positive

• CEO’s direct ownership increased by 1,597 shares, enhancing management–shareholder alignment.

Negative

• None.

Insights

Corporate Governance Expert

TL;DR: Routine RSU vesting; CEO’s net long position rises modestly, governance impact neutral.

The activity is entirely compensation-related. Zimmerly allowed 2,260 RSUs to vest and surrendered 663 shares for taxes, increasing his direct stake by ~4.7%. Remaining unvested RSUs (18,894) extend retention incentives through 2028. No open-market buying or selling occurred, so market-signal value is limited, yet the growing ownership base modestly reinforces management-shareholder alignment. Impact on governance risk is neutral to slightly positive.

Portfolio Manager

TL;DR: Insider net add of 1.6k shares is small; not an actionable catalyst.

Net purchase value (vested less withheld) is roughly $43k—immaterial versus MBCN’s ~$180 m market cap. The absence of discretionary buying tempers any bullish read-through. Still, the CEO now controls ~45k shares (direct + IRA + RSUs at target), maintaining skin in the game. I classify the event as non-impactful for portfolio weighting.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Zimmerly Ronald Len Jr.

(Last) (First) (Middle)

15985 EAST HIGH STREET

(Street)

MIDDLEFIELD OH 44062

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
MIDDLEFIELD BANC CORP [ MBCN ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Executive Officer

3. Date of Earliest Transaction (Month/Day/Year)
08/06/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	08/06/2025		A(1)		2,260	A	$27.11	36,503.283(2)	D
Common Stock	08/06/2025		F		663	D	$27.11	35,840.283(2)	D
Common Stock								8,786	I	Held in IRA

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Conditional Stock Award(3)	(4)							(3)	08/30/2027	Common Stock	4,520		4,520	D
Conditional Stock Award(5)	$27.4							(5)	03/10/2026	Common Stock	3,722		3,722	D
Conditional Stock Award(6)	$28.6							(6)	12/01/2025	Common Stock	3,788		3,788	D
Conditional Stock Award(7)	(4)	01/14/2025		A		6,864		(7)	01/14/2028	Common Stock	6,864	(4)	6,864	D

Explanation of Responses:

1. The acquisition represents the vesting of restricted stock granted to the reporting person on August 6, 2024. The shares vested on the first anniversary of the grant date.

2. Includes shares acquired under MBCN Dividend Reinvestment Plan

3. The award represents a grant of restricted stock which vests ratably over a three-year period provided that Mr. Zimmerly 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 September 4, 2024.

4. Each restricted stock unit represents the right to receive, at settlement, one share of common stock.

5. Until the award vests, the award confers no right to vote, no right to dividends, and no other shareholder rights to the recipient. Vesting is subject to a time-based or service condition and a performance-based condition. The details of the vesting conditions may be found in a Form 8K filing dated March 17, 2023.

6. The award represents a grant of restricted stock which vests ratably over a three-year period provided that Mr. Zimmerly 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.

7. The award represents a grant of restricted stock which vests ratably over a three-year period provided that Mr. Zimmerly 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.

	/s/ Ronald L. Zimmerly, Jr. by Julie E. Shaw Power of Attorney	08/07/2025
	** Signature of Reporting Person	Date
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FAQ

How many MBCN shares does CEO Ronald L. Zimmerly Jr. now own directly?

After the reported transactions he holds 35,840.283 direct shares.

What triggered the share acquisition on 08/06/2025?

It was the vesting of a 2,260-share restricted stock grant issued 08/06/2024.

Why were 663 shares disposed of in the same filing?

Those shares were withheld to cover tax obligations associated with the vesting (Code F).

How many unvested RSUs does the CEO still hold?

He has 18,894 restricted stock units scheduled to vest between 2025-2028.

Is there any open-market buying or selling by the CEO?

No. The filing only shows automatic vesting and tax withholding; no discretionary trades occurred.