Axcelis (ACLS) CEO sells 1,244 shares under 10b5-1 plan

Rhea-AI Filing Summary

Axcelis Technologies president and CEO Russell Low executed an open-market sale of 1,244 shares of common stock at $94.06 per share on April 1, 2026. The transaction was made under a pre-arranged Rule 10b5-1 trading plan adopted on December 11, 2025.

Following this sale, Low directly holds 132,282 shares of Axcelis common stock. Of these, 83,480 shares are issuable upon vesting of restricted stock units granted under the 2012 Equity Incentive Plan and remain subject to forfeiture.

Insider Trade Summary 10b5-1

Net Seller: 1,244 shares ($117,011)

Net Sell 1 txn

Insider Low Russell

Role PRESIDENT AND CEO

Sold 1,244 shs ($117K)

Type	Security	Shares	Price	Value
Sale	Common Stock	1,244	$94.06	$117K

Holdings After Transaction: Common Stock — 132,282 shares (Direct)

Footnotes (1)

1. This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 11, 2025. Of the shares held after this sale on April 1, 2026, 83,480 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture.

Key Figures

Shares sold: 1,244 shares Sale price per share: $94.06 per share Shares held after transaction: 132,282 shares +2 more

5 metrics

Shares sold 1,244 shares Open-market sale on April 1, 2026

Sale price per share $94.06 per share Price for common stock sold

Shares held after transaction 132,282 shares Direct holdings following sale

RSU-related shares 83,480 shares Issuable upon vesting of restricted stock units; subject to forfeiture

Trading plan adoption date December 11, 2025 Date Rule 10b5-1 trading plan was adopted

Key Terms

Rule 10b5-1 trading plan, restricted stock units, 2012 Equity Incentive Plan

3 terms

Rule 10b5-1 trading plan regulatory

"This transaction was made pursuant to a Rule 10b5-1 trading plan adopted"

A Rule 10b5-1 trading plan is a pre-arranged schedule that allows company insiders to buy or sell stock at specific times, even if they have inside information. It helps prevent accusations of unfair trading by making these transactions look planned and transparent, rather than sneaky or illegal.

restricted stock units financial

"83,480 were issuable on vesting of restricted stock units granted"

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

2012 Equity Incentive Plan financial

"restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan"

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).

X

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^*

Low Russell

(Last) (First) (Middle)

C/O AXCELIS TECHNOLOGIES, INC.

108 CHERRY HILL DRIVE

(Street)

BEVERLY MASSACHUSETTS 01915

(City) (State) (Zip)

UNITED STATES

(Country)

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

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

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	PRESIDENT AND CEO

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
04/01/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

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	04/01/2026		S(1)		1,244	D	$94.06	132,282(2)	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 transaction was made pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 11, 2025.

2. Of the shares held after this sale on April 1, 2026, 83,480 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	04/02/2026
	** 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).
** 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.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did Axcelis Technologies (ACLS) report for Russell Low?

Axcelis Technologies reported that president and CEO Russell Low sold 1,244 shares of common stock in an open-market transaction. The sale occurred on April 1, 2026, and was executed at a price of $94.06 per share under a pre-arranged Rule 10b5-1 trading plan.

Was the Axcelis (ACLS) CEO’s share sale pre-planned under a Rule 10b5-1 plan?

Yes. The sale by Axcelis CEO Russell Low was made pursuant to a Rule 10b5-1 trading plan adopted on December 11, 2025. Such plans pre-schedule trades, indicating the timing of this 1,244-share sale was established in advance rather than decided spontaneously.

How many Axcelis (ACLS) shares does CEO Russell Low hold after this transaction?

After selling 1,244 shares, Russell Low directly holds 132,282 shares of Axcelis common stock. This total includes a substantial portion tied to equity compensation, providing ongoing exposure to the company’s performance following the open-market sale reported in this Form 4 filing.

How many of Russell Low’s Axcelis (ACLS) shares are from restricted stock units?

Of the 132,282 shares held after the sale, 83,480 are issuable upon vesting of restricted stock units. These RSUs were granted under Axcelis’s 2012 Equity Incentive Plan and remain subject to forfeiture until vesting conditions are satisfied by the CEO.

What price did the Axcelis (ACLS) CEO receive per share in the reported sale?

Russell Low sold 1,244 shares of Axcelis common stock at a price of $94.06 per share. This per-share amount reflects the execution price for the April 1, 2026 open-market transaction disclosed in the Form 4 insider trading report for the company’s CEO.