[Form 4] Ultra Clean Holdings, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Christopher S. Cook, President, Products Division of Ultra Clean Holdings, Inc., reported an equity award on Form 4 showing acquisition of 73,686 restricted stock units on 08/29/2025 at no cash price. After the award, Mr. Cook beneficially owned 130,015 shares of Common Stock directly and had an additional 4,100 shares held indirectly by a trust. The restricted stock units vest over three years in equal annual installments beginning on the vesting commencement date of 08/29/2025. The Form 4 was signed by an attorney-in-fact on behalf of Mr. Cook on 09/03/2025.

Positive

• 73,686 restricted stock units were granted, increasing direct beneficial ownership to 130,015 shares
• The RSUs have a clear three-year vesting schedule with equal annual vesting, aligning compensation with tenure

Negative

• None.

Insights

Financial Analyst

TL;DR: Routine equity grant increases insider ownership but contains no cash purchase or immediate dilution details.

The filing documents a grant of 73,686 restricted stock units to an executive, which increases reported direct beneficial ownership to 130,015 shares and shows 4,100 shares held indirectly by trust. Because the awards vest over three years, the economic and voting rights are subject to future vesting events; the report does not disclose exercise of options or sale activity. This disclosure is standard for executive compensation and aligns management incentives with shareholder outcomes, but it does not provide financial impact on outstanding share count or potential accounting expense details.

Corporate Governance Expert

TL;DR: Standard restricted stock unit grant with multi-year vesting; governance implication is alignment of executive interests with long-term performance.

The Form 4 shows an equity award with a clear vesting schedule: equal parts vesting on each anniversary over three years from 08/29/2025. The filing names the reporting person and role, and indicates direct and indirect holdings separately. The document was executed by an attorney-in-fact, consistent with procedural practice. The disclosure is complete for Section 16 purposes but does not include broader compensation plan terms or any acceleration provisions.

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

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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^*

Cook Christopher S

(Last) (First) (Middle)

ULTRA CLEAN HOLDINGS, INC.

26462 CORPORATE AVENUE

(Street)

HAYWARD CA 94545

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Ultra Clean Holdings, Inc. [ UCTI ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	President, Products Division

3. Date of Earliest Transaction (Month/Day/Year)
08/29/2025

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	08/29/2025		A		73,686(1)	A	$0	130,015	D
Common Stock								4,100	I	by Trust

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

Explanation of Responses:

1. Restricted stock units vest over 3 years with equal parts vesting on each anniversary of the vesting commencement date of August 29, 2025.

	/s/ Paul Y. Cho, as attorney-in-fact for Christopher S. Cook	09/03/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did Ultra Clean Holdings (UCTI) report on this Form 4?

The Form 4 reports that Christopher S. Cook acquired 73,686 restricted stock units on 08/29/2025, increasing his direct beneficial ownership to 130,015 shares.

What is the vesting schedule for the restricted stock units?

The restricted stock units vest over 3 years with equal parts vesting on each anniversary of the vesting commencement date of 08/29/2025.

Does the Form 4 show any cash purchase price for the RSUs?

No. The transaction is reported at a $0 price for the restricted stock units acquired on 08/29/2025.

Are there any indirect holdings reported for the reporting person?

Yes. The filing shows 4,100 shares held indirectly by a trust in addition to direct beneficial ownership.

Who signed the Form 4 and when?

The Form 4 was signed by /s/ Paul Y. Cho, as attorney-in-fact for Christopher S. Cook on 09/03/2025.