Was the Axcelis (ACLS) CEO’s May 2026 share sale pre-planned under Rule 10b5-1?

Yes. The filing states the 1,244-share sale on May 1, 2026 was made pursuant to a Rule 10b5-1 trading plan that Russell Low adopted on December 11, 2025 , indicating the transaction was scheduled in advance.

Axcelis (NASDAQ: ACLS) CEO sells 1,244 shares in Rule 10b5-1 trade

Q: How many Axcelis (ACLS) shares does CEO Russell Low hold after the reported sale?

After the May 1, 2026 sale, Russell Low directly held 131,038 shares of Axcelis common stock. This total includes 83,480 shares issuable upon vesting of restricted stock units granted under the company’s 2012 Equity Incentive Plan.

Q: What price did Axcelis (ACLS) CEO Russell Low receive for the shares sold?

Russell Low’s open-market sale on May 1, 2026 involved 1,244 common shares at a price of $138.86 per share . This price is explicitly disclosed in the Form 4 insider trading report filed for Axcelis Technologies.

Q: How many restricted stock units does the Axcelis (ACLS) CEO have after the sale?

Following the May 1, 2026 transaction, 83,480 shares of Axcelis common stock held by Russell Low were issuable upon vesting of restricted stock units granted under the 2012 Equity Incentive Plan and remain subject to forfeiture.

Filing Impact

(High)

Filing Sentiment

(Negative)

Form Type

Rhea-AI Filing Summary

Axcelis Technologies Inc. president and CEO Russell Low reported an open-market sale of 1,244 shares of common stock at $138.86 per share on May 1, 2026. The transaction was executed under a pre-arranged Rule 10b5-1 trading plan adopted on December 11, 2025.

After this sale, Low directly held 131,038 shares of Axcelis common stock. Of this amount, 83,480 shares were issuable upon vesting of restricted stock units granted under the company’s 2012 Equity Incentive Plan and remain subject to forfeiture.

Insider Trade Summary 10b5-1

Net Seller: 1,244 shares ($172,742)

Net Sell 1 txn

Insider Low Russell

Role PRESIDENT AND CEO

Sold 1,244 shs ($173K)

Type	Security	Shares	Price	Value
Sale	Common Stock	1,244	$138.86	$173K

Holdings After Transaction: Common Stock — 131,038 shares (Direct, null)

Footnotes (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 May 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: $138.86 per share Shares held after transaction: 131,038 shares +1 more

4 metrics

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

Sale price per share $138.86 per share Price for common stock sold May 1, 2026

Shares held after transaction 131,038 shares Direct holdings following May 1, 2026 sale

RSU-linked shares 83,480 shares Issuable upon vesting under 2012 Equity Incentive Plan; subject to forfeiture

Key Terms

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

4 terms

Rule 10b5-1 trading plan regulatory

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

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 to the reporting person"

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"

open-market sale financial

"transaction_action: open-market sale"

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

Form 4 Insider Transactions: What Each Field Means →

05/04/2026 - 05:05 PM

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^*

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)
05/01/2026

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	05/01/2026		S⁽¹⁾		1,244	D	$138.86	131,038⁽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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

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 May 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	05/04/2026
	** 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)

Source: View Original Filing on SEC EDGAR

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 at $138.86 per share on May 1, 2026, under a pre-arranged Rule 10b5-1 trading plan.

How many Axcelis (ACLS) shares does CEO Russell Low hold after the reported sale?

After the May 1, 2026 sale, Russell Low directly held 131,038 shares of Axcelis common stock. This total includes 83,480 shares issuable upon vesting of restricted stock units granted under the company’s 2012 Equity Incentive Plan.

What price did Axcelis (ACLS) CEO Russell Low receive for the shares sold?

Russell Low’s open-market sale on May 1, 2026 involved 1,244 common shares at a price of $138.86 per share. This price is explicitly disclosed in the Form 4 insider trading report filed for Axcelis Technologies.

How many restricted stock units does the Axcelis (ACLS) CEO have after the sale?

Following the May 1, 2026 transaction, 83,480 shares of Axcelis common stock held by Russell Low were issuable upon vesting of restricted stock units granted under the 2012 Equity Incentive Plan and remain subject to forfeiture.