Amentum Holdings, Inc. AMTM

Set alert

21.37 USD -0.86 (-3.87%)

At closeNov 5, 2026, 6:18 PM EST

21.20 -0.17 -0.80%

After hours · Nov 5, 6:18 PM ET

20.98 Day range 22.26

17.72 52-week range 38.11

Held by insiders 1.17%

Held by institutions 106.10%

Float held by institutions 107.36%

Institutions 606

Top institutional holders
Holder	% held	Shares	Value	Reported
American Securities LLC	18.42%	45,026,743	959.75M	Jun 29, 2026
Invesco Ltd.	10.21%	24,954,251	531.90M	Jun 29, 2026
Blackrock Inc.	7.32%	17,906,984	381.69M	Jun 29, 2026
Primecap Management Company	5.02%	12,285,504	261.87M	Jun 29, 2026
Vanguard Portfolio Management LLC	3.25%	7,948,385	169.42M	Jun 29, 2026
Dimensional Fund Advisors LP	2.95%	7,210,730	153.70M	Sep 29, 2026

Top mutual fund holders
Holder	% held	Shares	Value	Reported
iShares Trust-iShares Core S&P Small-Cap ETF	3.75%	9,171,825	195.50M	Sep 29, 2026
VANGUARD FENWAY FUNDS-Vanguard PRIMECAP Core Fund	2.26%	5,516,796	117.59M	Jun 29, 2026
VANGUARD INDEX FUNDS-Vanguard Total Stock Market Index Fund	1.90%	4,653,337	99.19M	Jun 29, 2026
AIM Sector Funds (Invesco Sector Funds)-Invesco Small Cap Value Fund	1.73%	4,226,948	90.10M	Jul 30, 2026
VANGUARD INDEX FUNDS-Vanguard Small-Cap Index Fund	1.38%	3,363,425	71.69M	Jun 29, 2026
AIM Sector Fd.s -INVESCO VALUE OPPORTUNITIES Fd.	1.20%	2,945,078	62.77M	Jul 30, 2026

AMTM insiders
Insider	Relation	Latest transaction	Date	Shares held
AMENTUM JOINT VENTURE GP LLC	Director	Stock Award(Grant)	Apr 6, 2025	0
ARNETTE STEPHEN A	Chief Operating Officer	Conversion of Exercise of derivative security	May 5, 2026	106,652
BRUNING JILL L	Chief Technology Officer	Conversion of Exercise of derivative security	May 5, 2026	197,457
DEMETRIOU STEVEN J	Officer and Director	Stock Award(Grant)	Nov 16, 2025	844,026
EBERHART RALPH EDWARD	Director	Conversion of Exercise of derivative security	Mar 4, 2025	29,886
HELLER JOHN E	Chief Executive Officer	Conversion of Exercise of derivative security	May 5, 2026	376,019

Held by funds