MICHAEL RANTTILA - 17 Dec 2025 Form 4 Insider Report for MIDDLEFIELD BANC CORP (MBCN)

Role: EVP/CFO
Signature: /s/ Michael Ranttila by Julie E. Shaw Power of Attorney
Issuer symbol: MBCN
Transactions as of: 17 Dec 2025
Net transactions value: +$455,433
Form type: 4
Filing time: 18 Dec 2025, 17:22:31 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
RANTTILA MICHAEL	EVP/CFO	15985 EAST HIGH STREET, MIDDLEFIELD	/s/ Michael Ranttila by Julie E. Shaw Power of Attorney	18 Dec 2025	0001792684

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	MBCN	Common Stock	Award	$131,646	+3,558	+58%	$37.00	9,729	17 Dec 2025	Direct	F1, F3
transaction	MBCN	Common Stock	Award	$470,381	+12,713	+131%	$37.00	22,442	17 Dec 2025	Direct	F2, F3
transaction	MBCN	Common Stock	Tax liability	$146,594	-3,962	-18%	$37.00	18,480	17 Dec 2025	Direct	F3
holding	MBCN	Common Stock						50	17 Dec 2025	as Custodian for Grandson
holding	MBCN	Common Stock						300	17 Dec 2025	held in IRA

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						3,014	17 Dec 2025	Common Stock	3,014		Direct	F4, F6
holding	MBCN	Conditional Stock Award						4,433	17 Dec 2025	Common Stock	4,433		Direct	F5, F6

* 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 details of the accelerated restricted stock grants may be found in a Form 8-K filed December 12, 2025.
F2	Amendment of performance share unit award agreement resulting in acceleration of performance share unit grants. The details of the accelerated performance share unit grants may be found in a Form 8-K filed December 12, 2025.
F3	Includes shares acquired under MBCN Dividend Reinvestment Plan
F4	The award represents a grant of restricted stock which vests ratably over a three-year period provided that Mr. Ranttila 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.
F5	The award represents a grant of restricted stock which vests ratably over a three-year period provided that Mr. Ranttila 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 filing dated January 17, 2025.
F6	Each restricted stock unit represents the right to receive, at settlement, one share of common stock.