---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-24-227910"
form_type: "8-K"
ticker: "AMTM"
cik: "0002011286"
company_name: "Amentum Holdings, Inc."
filed_at: "2024-09-27T23:59:59+00:00"
generated_at: "2026-05-31T01:24:16.898772+00:00"
event_type: "leadership"
sentiment: "neutral"
materiality_score: 0.5
calibrated_materiality_score: 0.5
confidence: "high"
source: SEC EDGAR
---

# Amentum names Stephen A. Arnette as COO; authorizes 1B shares, effects stock split

## Summary
- Stephen A. Arnette appointed Chief Operating Officer, effective September 27, 2024.
- Board increased authorized shares to 1,000,000,000 via amendment to certificate of incorporation.
- Stock split of outstanding common stock resulted in 153,280,369 issued and outstanding shares.
- Actions taken in connection with Jacobs Solutions' distribution of Amentum shares to Jacobs stockholders.

## SEC filing metadata
- accession: 0001193125-24-227910
- form_type: 8-K
- ticker: AMTM
- cik: 0002011286
- company_name: Amentum Holdings, Inc.
- filed_at: 2024-09-27T23:59:59+00:00
- event_type: leadership
- sentiment: neutral
- materiality_score: 0.5
- calibrated_materiality_score: 0.5
- confidence: high
- sec_items: 5.02, 5.03, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/2011286/000119312524227910/0001193125-24-227910-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/2011286/000119312524227910/d905502d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-24-227910
- JSON: https://secwatch.observer/filing/0001193125-24-227910.json
- Plain text: https://secwatch.observer/filing/0001193125-24-227910.txt

## Key facts
- Executive change
  Stephen A. Arnette was appointed as Chief Operating Officer at Amentum Holdings, Inc..
  - Action: appointed
  - Role: Chief Operating Officer
  source text: appointed Stephen A. Arnette as Chief Operating Officer of the Company, with such appointment to be effective September 27, 2024.
  evidence_url: https://www.sec.gov/Archives/edgar/data/2011286/000119312524227910/0001193125-24-227910-index.htm

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.