First Manhattan’s Amentum Holdings AMTM Stock Holding History

First Manhattan’s Portfolio AMTM Stock Details AMTM Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q2	$294K	Buy	14,242 +125	+0.9%	+$3.02K	﹤0.01%	662
2026 Q1	$368K	Hold	14,117	–	–	﹤0.01%	626
2025 Q4	$409K	Sell	14,117 -83	-0.6%	-$2.12K	﹤0.01%	596
2025 Q3	$340K	Sell	14,200 -1,235	-8%	-$30.1K	﹤0.01%	606
2025 Q2	$364K	Sell	15,435 -574	-4%	-$12K	﹤0.01%	588
2025 Q1	$291K	Sell	16,009 -1,593	-9%	-$32.4K	﹤0.01%	590
2024 Q4	$370K	Buy	+17,602	New	+$455K	﹤0.01%	562

Other funds holding AMTM

American Securities New York $3.75B AUM 23.12% 1-Year Est. Return

Invesco Atlanta, Georgia $1.26T AUM 61.52% 1-Year Est. Return

BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return

Primecap Management Pasadena, California $169B AUM 114.72% 1-Year Est. Return

Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM

Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM

Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return

Dimensional Fund Advisors Austin, Texas $552B AUM 44.19% 1-Year Est. Return

State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return

FCM

Frontier Capital Management Boston, Massachusetts $10.7B AUM 67.78% 1-Year Est. Return

First Manhattan's AMTM Position: Q2 2026 in Review

First Manhattan increased its Amentum Holdings (AMTM) stake by 0.89% in Q2 2026, buying an estimated $3.02K and bringing the position to 14,242 shares worth $294K. The position accounts for ﹤0.01% of the portfolio, ranked #662.

First Manhattan first reported a position in AMTM in Q4 2024 and has held it in 7 quarters since. The position peaked at $409K in Q4 2025. 462 funds tracked by Wall St. Rank hold AMTM as of Q2 2026.

First Manhattan held 14,242 shares of Amentum Holdings worth $294K as of Q2 2026.
First Manhattan bought 125 Amentum Holdings shares in Q2 2026, an estimated $3.02K.
Amentum Holdings made up ﹤0.01% of First Manhattan's portfolio in Q2 2026, its #662 holding.
First Manhattan first reported a position in Amentum Holdings in Q4 2024 and has held it in 7 quarters since.
First Manhattan's Amentum Holdings position peaked at $409K in Q4 2025.
462 funds tracked by Wall St. Rank held Amentum Holdings as of Q2 2026.

Based on First Manhattan's 13F filing for Q2 2026, filed 14 Aug 2026.