John Overdeck’s Amentum Holdings AMTM Stock Holding History

John Overdeck’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	$5.88M	Sell	284,268 -615,909	-68%	-$14.9M	﹤0.01%	1986
2026 Q1	$23.5M	Buy	900,177 +262,191	+41%	+$8.23M	0.02%	860
2025 Q4	$18.5M	Buy	637,986 +238,863	+60%	+$6.11M	0.03%	766
2025 Q3	$9.56M	Buy	399,123 +385,394	+2,807%	+$9.38M	0.01%	983
2025 Q2	$324K	Sell	13,729 -40,371	-75%	-$844K	﹤0.01%	2761
2025 Q1	$985K	Buy	+54,100	New	+$1.1M	﹤0.01%	2184
2024 Q4	–	Sell	-321,096	Closed	-$10.4M	–	3550
2024 Q3	$10.4M	Buy	+321,096	New	+$9.15M	0.02%	746

Other funds holding AMTM

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

TCA

Troluce Capital Advisors Dorado, Puerto Rico $971M AUM 2.27% 1-Year Est. Return

John Overdeck's AMTM Position: Q2 2026 in Review

John Overdeck reduced its Amentum Holdings (AMTM) stake by 68% in Q2 2026, selling an estimated $14.9M and leaving 284,268 shares worth $5.88M. The position accounts for ﹤0.01% of the portfolio, ranked #1986.

John Overdeck first reported a position in AMTM in Q3 2024 and has held it in 7 quarters since. The position peaked at $23.5M in Q1 2026. 457 funds tracked by Wall St. Rank hold AMTM as of Q2 2026.

John Overdeck held 284,268 shares of Amentum Holdings worth $5.88M as of Q2 2026.
John Overdeck sold 615,909 Amentum Holdings shares in Q2 2026, an estimated $14.9M.
Amentum Holdings made up ﹤0.01% of John Overdeck's portfolio in Q2 2026, its #1986 holding.
John Overdeck first reported a position in Amentum Holdings in Q3 2024 and has held it in 7 quarters since.
John Overdeck's Amentum Holdings position peaked at $23.5M in Q1 2026.
457 funds tracked by Wall St. Rank held Amentum Holdings as of Q2 2026.

Based on Two Sigma Investments's 13F filing for Q2 2026, filed 14 Aug 2026.