Form 4: Amentum COO Stephen Arnette's Stock Vesting & Tax Sale

Amentum Holdings COO Stephen Arnette reported the vesting of restricted stock units and subsequent sale of shares for tax withholding.

Summary

• Stephen A. Arnette, Chief Operating Officer of Amentum Holdings, Inc. (AMTM), reported transactions on November 6, 2025.
• 12,701 shares of AMTM common stock were acquired upon the vesting of restricted stock units.
• 3,093 shares of AMTM common stock were disposed of at a price of $21.79 per share to cover tax withholding obligations related to the vesting.
• Following these transactions, Arnette directly beneficially owns 31,628 shares of common stock and 25,404 restricted stock units.

Sentiment

Score: 7

Explanation: The filing reports a routine executive compensation event involving the vesting of restricted stock units and a standard tax-related share disposal, indicating normal course of business without significant positive or negative implications beyond the expected.

Positives

• The vesting of 12,701 restricted stock units represents a realization of executive compensation for the Chief Operating Officer.

Negatives

• 3,093 shares of common stock were sold to cover tax withholding, resulting in a reduction of direct share ownership.

Stakeholder Impact

• Shareholders: Minor, routine impact from the vesting of restricted stock units, which is a standard component of executive compensation and an expected source of share issuance.
• Employees (Executive): Positive impact for Stephen A. Arnette, as a portion of his compensation in the form of restricted stock units has vested and converted to common stock.

Key Dates

Recommendation

This Form 4 filing details a routine executive compensation event involving the vesting of restricted stock units and a subsequent sale of shares to cover tax liabilities. Such transactions are standard and do not typically provide new fundamental information that would alter an investment thesis for Amentum Holdings, Inc. Therefore, a 'hold' recommendation is appropriate as the filing does not present a catalyst for a change in valuation or outlook.

Keywords

Amentum Holdings, AMTM, Form 4, Insider Transaction, Stock Vesting, Restricted Stock Units, Executive Compensation, Stephen Arnette, Tax Withholding