Blumenstock Gerald M 4

4 · AXCELIS TECHNOLOGIES INC · Filed Mar 3, 2026

AI-generated summary of this filing

Updated Mar 3, 2026

Axcelis (ACLS) EVP Gerald Blumenstock Forfeits 1,121 Shares for Taxes

What Happened

Gerald M. Blumenstock, Executive Vice President, Research, Development & Engineering at Axcelis Technologies, forfeited 1,121 shares on March 2, 2026 to satisfy tax withholding obligations related to the vesting of performance-based restricted stock units (2024 PRSUs). The withholding value was $97,056, based on the closing price of $86.58 on March 2, 2026.
This was a tax-withholding forfeiture (transaction code F), not an open-market sale or purchase.

Key Details

Transaction date: 2026-03-02; filing date: 2026-03-03 (no late filing indicated).
Price used for value: $86.58 (closing price on 3/2/2026).
Shares forfeited/withheld: 1,121; value: $97,056.
Reason: Withholding to cover tax obligations on 2024 PRSUs that vested on February 28, 2026.
Grant background: The 2024 PRSUs were granted in May 2024 and were earned at 150% by Compensation Committee resolution (2/13/2025); half of the earned shares vested 2/28/2025 and the remainder vested 2/28/2026.
Post-vesting note: Of the shares held after the vesting of the remaining 2024 PRSUs, 16,525 were issuable on vesting of other restricted stock units and remain subject to forfeiture.

Context

This is a routine tax-withholding event (shares surrendered to cover taxes) rather than an intentional market sale or purchase; such transactions are common when equity awards vest and do not necessarily signal insider sentiment.

Form 4

Period: 2026-03-02

EVP, Research, Dev. & Eng.

Transactions

Tax Payment
Common Stock
[F2][F1][F3]
2026-03-02$86.58/sh−1,121$97,056→ 17,540 total

Footnotes (3)

[F1]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.
[F2]Represents the closing price of the Company's common stock on March 2, 2026, the date of the tax withholding.
[F3]Of the shares held after the vesting of the remaining 2024 PRSUs, 16,525 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture.

Signature

/s/ Eileen J. Evans, Attorney-in-Fact|2026-03-03

1 file