Courtney M. Erminio - 17 Dec 2025 Form 4 Insider Report for MIDDLEFIELD BANC CORP (MBCN)

Role: EVP/Chief Risk Officer
Signature: /s/ Courtney M. Erminio by Julie E. Shaw Power of Attorney
Issuer symbol: MBCN
Transactions as of: 17 Dec 2025
Net transactions value: +$112,369
Form type: 4
Filing time: 18 Dec 2025, 16:10:21 UTC
Previous filing: 07 Aug 2025
Next filing: 16 Jan 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Erminio Courtney M	EVP/Chief Risk Officer	15985 EAST HIGH STREET, MIDDLEFIELD	/s/ Courtney M. Erminio by Julie E. Shaw Power of Attorney	18 Dec 2025	0001698885

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	MBCN	Common Stock	Award	$75,295	+2,035	+46%	$37.00	6,472	17 Dec 2025	Direct	F1, F3
transaction	MBCN	Common Stock	Award	$81,548	+2,204	+34%	$37.00	8,676	17 Dec 2025	Direct	F2, F3
transaction	MBCN	Common Stock	Tax liability	$44,474	-1,202	-14%	$37.00	7,474	17 Dec 2025	Direct	F3
holding	MBCN	Common Stock						151	17 Dec 2025	Direct	F3, F4

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
holding	MBCN	Conditional Stock Award						1,708	17 Dec 2025	Common Stock	1,708		Direct	F5, F7
holding	MBCN	Conditional Stock Award						2,828	17 Dec 2025	Common Stock	2,828		Direct	F6, F7

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Amendment of conditional stock award agreement resulting in acceleration of restricted stock grants. The restricted stock award was originally granted on March 10, 2023, and provides for vesting on the third anniversary of the award.
F2	Amendment of performance share unit award agreement resulting in acceleration of performance share unit grants. The performance share unit award was originally granted on August 6, 2024, and provides for vesting in any earned performance share units upon the payment date, defined as within sixty days after December 31, 2026.
F3	Includes shares acquired under MBCN Dividend Reinvestment Plan
F4	Includes shares held jointly with spouse.
F5	The award represents a grant of restricted stock which vests ratably over a three-year period provided that Mrs. Erminio 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 8-K dated September 4, 2024.
F6	The award represents a grant of restricted stock which vests ratably over a three-year period provided that Mrs. Erminio 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 8-K dated January 17, 2025.
F7	Each restricted stock unit represents the right to receive, at settlement, one share of common stock.