ACM Research Insider Net-Exercise Adds 130,000 Shares

Rhea-AI Filing Summary

David H. Wang, CEO and Director of ACM Research, Inc. (ACMR), exercised 130,000 vested stock options by net exercise on 09/08/2025 at an exercise price of $1 per share. The filing shows the option was fully vested and the net exercise closed on that date, resulting in 610,002 shares held directly after the transaction. The report also discloses indirect holdings: 100,002 shares held by Jing Chen (his wife), 45,837 by his daughter Sophia Wang, 180,000 by a family trust for his children, and 620,001 by the Wang-Chen Family Living Trust. The Form 4 was signed by an attorney-in-fact on 09/30/2025.

Positive

• Insider exercised 130,000 vested options, increasing direct ownership and converting compensation into equity
• Transaction executed at $1 per share, with the option described as fully vested
• Full disclosure of indirect holdings (spouse, daughter, trusts) with specific share counts

Negative

• None.

Insights

Financial Analyst

TL;DR: Insider exercised 130,000 vested options, increasing direct holdings to 610,002 shares—a meaningful insider purchase signal.

The transaction is a net exercise of previously granted options at $1 per share, executed on 09/08/2025 for 130,000 shares. Net exercises convert options into common stock without an immediate cash outlay equal to the full strike cost, and here the reporting person increases direct equity to 610,002 shares. From a capital-structure perspective this is a routine conversion of options to shares and the filing states the options were fully vested.

Corporate Governance Expert

TL;DR: Filing documents a standard, vested-option exercise and lists related-party indirect holdings; disclosure appears complete and procedural.

The Form 4 identifies the reporting person as CEO, President and Director and discloses indirect ownership through spouse, child and family trusts with specific share counts. The form was executed by an attorney-in-fact. The filing includes the required transaction code (M) and vesting statement; no amendments or qualifications are noted within the document provided.

Insider Trade Summary

130,000 shares exercised/converted

Mixed 6 txns

Insider Wang David H

Role See Remarks

Type	Security	Shares	Price	Value
Exercise	Stock Option	130,000	$0.00	--
Exercise	Class A Common Stock	130,000	$1.00	$130K
holding	Class A Common Stock	--	--	--
holding	Class A Common Stock	--	--	--
holding	Class A Common Stock	--	--	--
holding	Class A Common Stock	--	--	--

Holdings After Transaction: Stock Option — 610,002 shares (Direct); Class A Common Stock — 802,708 shares (Direct); Class A Common Stock — 100,002 shares (Indirect, By Jing Chen, wife of David H. Wang)

Footnotes (1)

1. On September 8, 2025, the reporting person exercised, by net exercise, a previously issued stock option to purchase 130,000 shares of Class A Common Stock of the Issuer. The option is fully vested and exercisable.

Form 4 Insider Transactions: What Each Field Means →

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
Estimated average burden
hours per response:			0.5

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

1. Name and Address of Reporting Person^*

Wang David H

(Last) (First) (Middle)

C/O ACM RESEARCH, INC.

42307 OSGOOD ROAD, SUITE I

(Street)

FREMONT CA 94539

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
ACM Research, Inc. [ ACMR ]

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

X	Director	X	10% Owner
X	Officer (give title below)		Other (specify below)
	See Remarks

3. Date of Earliest Transaction (Month/Day/Year)
09/08/2025

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
Class A Common Stock	09/08/2025		M(1)		130,000	A	$1	802,708	D
Class A Common Stock								100,002	I	By Jing Chen, wife of David H. Wang
Class A Common Stock								45,837	I	By Sophia Wang, daughter of David H. Wang
Class A Common Stock								180,000	I	By David Hui Wang and Jing Chen Family Irrevocable Trust for Wang Children
Class A Common Stock								620,001	I	By Wang-Chen Family Living 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
Stock Option	$1	09/08/2025		M(1)			130,000	(2)	12/27/2026	Class A Common Stock	130,000	$0	610,002	D

Explanation of Responses:

1. On September 8, 2025, the reporting person exercised, by net exercise, a previously issued stock option to purchase 130,000 shares of Class A Common Stock of the Issuer.

2. The option is fully vested and exercisable.

Remarks:

Chief Executive Officer, President and Director

	/s/ Mark McKechnie, Attorney-in-Fact for David H. Wang	09/30/2025
	** 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 ACMR insider David H. Wang do on 09/08/2025?

He exercised 130,000 vested stock options by net exercise at an exercise price of $1 per share on 09/08/2025.

How many Class A shares does David H. Wang directly own after the transaction?

The filing reports 610,002 shares held directly following the reported transaction.

Does the Form 4 disclose indirect holdings for David H. Wang?

Yes. It lists 100,002 shares by Jing Chen (wife), 45,837 shares by Sophia Wang (daughter), 180,000 shares by a family trust for his children, and 620,001 shares by the Wang-Chen Family Living Trust.

Was the option exercised fully vested?

Yes. The filing explicitly states the option is fully vested and exercisable.

Who signed the Form 4 and when?

The Form 4 is signed by Mark McKechnie, Attorney-in-Fact for David H. Wang on 09/30/2025.