[Form 4] Amentum Holdings, Inc. Insider Trading Activity
Filing Impact
Filing Sentiment
Form Type
4
Rhea-AI Filing Summary
Amentum Holdings, Inc. Chief Operating Officer Stephen A. Arnette reported routine equity compensation activity involving restricted stock units. On May 6, 2026, 13,609 restricted stock units vested and were delivered as the same number of shares of AMTM common stock. Of these, 3,314 shares of common stock were tendered back to the company to satisfy tax withholding obligations, a non‑market disposition. As a result of these transactions, Arnette’s direct holdings increased, with the filing showing 109,966 shares of AMTM common stock held directly after the RSU-related activity.
Positive
- None.
Negative
- None.
Insider Trade Summary
13,609 shares exercised/converted
Mixed
3 txns
Insider
Arnette Stephen A
Role
Chief Operating Officer
| Type | Security | Shares | Price | Value |
|---|---|---|---|---|
| Exercise | Restricted Stock Units | 13,609 | $0.00 | -- |
| Exercise | Common Stock | 13,609 | $0.00 | -- |
| Tax Withholding | Common Stock | 3,314 | $24.89 | $82K |
Holdings After Transaction:
Restricted Stock Units — 13,609 shares (Direct, null);
Common Stock — 109,966 shares (Direct, null)
Footnotes (1)
- Represents distribution of AMTM common stock upon vesting of restricted stock units. Represents number of shares of AMTM common stock tendered for tax withholding upon vesting of restricted stock units. Each restricted stock unit represents a contingent right to receive one share of AMTM common stock. One-half of the restricted stock units shall vest and be delivered on the 18th month and three-year anniversaries of the date of grant.
Key Figures
RSUs vested: 13,609 units/shares
Shares for tax withholding: 3,314 shares
Direct holdings after transaction: 109,966 shares
+1 more
4 metrics
RSUs vested
13,609 units/shares
Restricted stock units vesting into AMTM common stock on May 6, 2026
Shares for tax withholding
3,314 shares
Common shares tendered to cover tax obligations on RSU vesting
Direct holdings after transaction
109,966 shares
AMTM common stock directly held by COO after Form 4 transactions
RSU-to-share ratio
1 RSU : 1 share
Each restricted stock unit represents one share of AMTM common stock
Key Terms
Restricted Stock Units, tax withholding, derivative security, contingent right, +1 more
5 terms
Restricted Stock Units financial
"Represents distribution of AMTM common stock upon vesting of restricted stock units."
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.
tax withholding financial
"Represents number of shares of AMTM common stock tendered for tax withholding upon vesting"
Tax withholding is the practice of taking a portion of a payment—such as wages, dividends, or sale proceeds—before it reaches the recipient and sending that portion to the tax authority as an advance on the recipient’s eventual tax bill. For investors it matters because withholding reduces immediate cash received and affects after‑tax returns, estimated tax payments, and whether you may owe more or receive a refund when taxes are finally calculated, like having a small automatic savings set aside for your tax bill.
derivative security financial
"transaction_code_description: Exercise or conversion of derivative security"
A derivative security is a financial contract whose value comes from the price or performance of something else, such as a stock, bond, commodity, or market index. For investors it acts like an insurance policy or a wager: it can be used to protect against losses, lock in prices, or amplify gains and losses, so it can change a portfolio’s risk and potential return without owning the underlying asset directly.
contingent right financial
"Each restricted stock unit represents a contingent right to receive one share"
vest and be delivered financial
"One-half of the restricted stock units shall vest and be delivered on the 18th month"
