AMTM

Industrials

Amentum Holdings, Inc.

$28.07+0.07 (+0.25%)

Prev Close

$28.00

Open

$28.11

High

$28.50

Low

$27.33

Volume

964.6K

Market Cap

$7.39B

P/E

70.18

Div Yield

—

Over the past 12 months, insider activity at Amentum Holdings, Inc. (AMTM) has been exclusively selling, with 0 insider purchases totaling $0.00 and 13 insider sales totaling $2.64M. The most recent insider transaction was by St. Mary Michele T (Chief Legal Officer & GC), who sold $69.4K worth of shares on Feb 17, 2026. Amentum Holdings, Inc. operates in the Industrials sector, within the Aerospace & Defense industry, with a market cap of $7.39B.

Buys (12M)

$0.00

Sells (12M)

$2.64M

Net Activity

Net Seller

$2.64M

Active Insiders

last 12 mo

AMTM Price Chart

AMTM Insider Trading Activity

Date	Insider	Role	Type	Shares	Avg Price	Value
Feb 17, 2026↗	St. Mary Michele T	Chief Legal Officer & GC	Sell	2,308	$30.05	$69.4K
Jan 28, 2026↗	Heller John E.	Chief Executive Officer	Sell	19,768	$35.71	$705.9K
Dec 17, 2025↗	Mullen Sean Thomas	Chief Growth Officer	Sell	4,194	$28.67	$120.2K
Dec 5, 2025↗	Burton Darren	Chief People Officer	Sell	1,392	$28.88	$40.2K
Nov 17, 2025↗	Arnette Stephen A	Chief Operating Officer	Sell	287	$21.49	$6.2K
Nov 17, 2025↗	DEMETRIOU STEVEN J.	Executive Chair	Sell	17,077	$21.49	$367.0K
Nov 15, 2025↗	Arnette Stephen A	Chief Operating Officer	Sell	4,651	$22.07	$102.6K
Nov 6, 2025↗	Arnette Stephen A	Chief Operating Officer	Sell	3,093	$21.79	$67.4K
Nov 6, 2025↗	Bruning Jill L	Chief Technology Officer	Sell	1,457	$21.79	$31.7K
Nov 6, 2025↗	DEMETRIOU STEVEN J.	Executive Chair	Sell	28,818	$21.79	$627.9K
Nov 6, 2025↗	Heller John E.	Chief Executive Officer	Sell	17,868	$21.79	$389.3K
Nov 6, 2025↗	Johnson Travis Barton	Chief Financial Officer	Sell	3,642	$21.79	$79.4K
Nov 6, 2025↗	Mullen Sean Thomas	Chief Growth Officer	Sell	1,621	$21.79	$35.3K
Mar 3, 2025↗	Arnette Stephen A	Chief Operating Officer	Sell	517	$19.37	$10.0K
Feb 18, 2025↗	Loughran Barbara	Director	Buy	4,600	$21.23	$97.6K
Feb 12, 2025↗	DEMETRIOU STEVEN J.	Executive Chair	Buy	100,000	$20.81	$2.08M

AMTM Insider Buying Activity

The following table shows recent insider purchases of Amentum Holdings, Inc. (AMTM) stock reported via SEC Form 4 filings.

Date	Insider	Role	Type	Shares	Avg Price	Value	Shares After
Feb 18, 2025↗	Loughran Barbara	Director	Buy	4,600	$21.23	$97.6K	0
Feb 12, 2025↗	DEMETRIOU STEVEN J.	Executive Chair	Buy	100,000	$20.81	$2.08M	0

AMTM Insider Selling Activity

The following table shows recent insider sales of Amentum Holdings, Inc. (AMTM) stock reported via SEC Form 4 filings.

Date	Insider	Role	Type	Shares	Avg Price	Value
Feb 17, 2026↗	St. Mary Michele T	Chief Legal Officer & GC	Sell	2,308	$30.05	$69.4K
Jan 28, 2026↗	Heller John E.	Chief Executive Officer	Sell	19,768	$35.71	$705.9K
Dec 17, 2025↗	Mullen Sean Thomas	Chief Growth Officer	Sell	4,194	$28.67	$120.2K
Dec 5, 2025↗	Burton Darren	Chief People Officer	Sell	1,392	$28.88	$40.2K
Nov 17, 2025↗	Arnette Stephen A	Chief Operating Officer	Sell	287	$21.49	$6.2K
Nov 17, 2025↗	DEMETRIOU STEVEN J.	Executive Chair	Sell	17,077	$21.49	$367.0K
Nov 15, 2025↗	Arnette Stephen A	Chief Operating Officer	Sell	4,651	$22.07	$102.6K
Nov 6, 2025↗	Arnette Stephen A	Chief Operating Officer	Sell	3,093	$21.79	$67.4K
Nov 6, 2025↗	Bruning Jill L	Chief Technology Officer	Sell	1,457	$21.79	$31.7K
Nov 6, 2025↗	DEMETRIOU STEVEN J.	Executive Chair	Sell	28,818	$21.79	$627.9K
Nov 6, 2025↗	Heller John E.	Chief Executive Officer	Sell	17,868	$21.79	$389.3K
Nov 6, 2025↗	Johnson Travis Barton	Chief Financial Officer	Sell	3,642	$21.79	$79.4K
Nov 6, 2025↗	Mullen Sean Thomas	Chief Growth Officer	Sell	1,621	$21.79	$35.3K
Mar 3, 2025↗	Arnette Stephen A	Chief Operating Officer	Sell	517	$19.37	$10.0K