Axcelis (NASDAQ: ACLS) EVP uses 573 shares to satisfy tax withholding

Rhea-AI Filing Summary

Axcelis Technologies executive vice president of global operations Robert John Mahoney reported a tax-withholding share disposition tied to vesting of performance-based restricted stock units. On March 2, 2026, 573 shares of common stock were forfeited at a price of $86.58 per share to satisfy tax obligations on 2024 PRSUs that vested on February 28, 2026. After this withholding, he beneficially owns 14,633 shares, including 10,543 shares issuable upon vesting of restricted stock units that remain subject to forfeiture.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Mahoney Robert John

Role EVP Global Operations

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	573	$86.58	$50K

Holdings After Transaction: Common Stock — 14,633 shares (Direct)

Footnotes (1)

1. This forfeiture of shares for tax withholding purposes relates to the vesting on February 28, 2026 of performance-based restricted stock units ("2024 PRSUs") granted to the executive in May 2024. Of the 2024 PRSUs granted, 150% were determined to be earned by the executive pursuant to a resolution of the Axcelis Technologies, Inc. Compensation Committee on February 13, 2025, with half of the earned shares vesting on February 28, 2025 and the remaining half of the earned shares vesting on February 28, 2026. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested 2024 PRSUs. Represents the closing price of the Company's common stock on March 2, 2026, the date of the tax withholding. Of the shares held after the vesting of the remaining 2024 PRSUs, 10,543 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture.

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).

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^*

Mahoney Robert John

(Last) (First) (Middle)

108 CHERRY HILL DRIVE

(Street)

BEVERLY MA 01915

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
AXCELIS TECHNOLOGIES INC [ ACLS ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP Global Operations

3. Date of Earliest Transaction (Month/Day/Year)
03/02/2026

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	03/02/2026		F		573	D(1)	$86.58(2)	14,633(3)	D

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. This forfeiture of shares for tax withholding purposes relates to the vesting on February 28, 2026 of performance-based restricted stock units ("2024 PRSUs") granted to the executive in May 2024. Of the 2024 PRSUs granted, 150% were determined to be earned by the executive pursuant to a resolution of the Axcelis Technologies, Inc. Compensation Committee on February 13, 2025, with half of the earned shares vesting on February 28, 2025 and the remaining half of the earned shares vesting on February 28, 2026. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested 2024 PRSUs.

2. Represents the closing price of the Company's common stock on March 2, 2026, the date of the tax withholding.

3. Of the shares held after the vesting of the remaining 2024 PRSUs, 10,543 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture.

	/s/ Eileen J. Evans, Attorney-in-Fact	03/03/2026
	** 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).
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FAQ

What insider transaction did Axcelis Technologies (ACLS) report for Robert John Mahoney?

Axcelis reported that EVP Global Operations Robert John Mahoney forfeited 573 common shares to cover tax withholding on vested 2024 performance-based RSUs. This was recorded at $86.58 per share and reflects a non-market tax-related disposition, not an open-market sale.

Why were 573 Axcelis (ACLS) shares forfeited by the executive?

The 573 shares were withheld to satisfy the executive’s tax obligation arising from the February 28, 2026 vesting of 2024 performance-based RSUs. The company reduced the shares issued on vesting by this amount to cover withholding taxes due on the earned awards.

How were the 2024 performance-based RSUs for Axcelis (ACLS) determined and vested?

The 2024 performance-based RSUs were granted in May 2024, and 150% of the target was determined earned by the compensation committee on February 13, 2025. Half of the earned shares vested on February 28, 2025, and the remaining half vested on February 28, 2026.

What was the reference price for the Axcelis (ACLS) tax-withholding shares?

The tax-withholding disposition used the closing price of Axcelis common stock on March 2, 2026, which was $86.58 per share. This price was applied to value the 573 forfeited shares used to satisfy the executive’s tax withholding obligation.

How many Axcelis (ACLS) shares does the executive hold after this transaction?

After the tax-withholding disposition, the executive beneficially owns 14,633 shares of Axcelis common stock. Of this amount, 10,543 shares are issuable upon vesting of restricted stock units granted under the 2012 Equity Incentive Plan and remain subject to forfeiture.

Are all of the Axcelis (ACLS) shares held by the executive fully vested?

No. Of the 14,633 shares beneficially owned after the transaction, 10,543 are tied to restricted stock units that will be issued only upon vesting. These unvested RSU-linked shares remain subject to forfeiture under the 2012 Equity Incentive Plan terms.