XT
AMTM

XTX Topco’s Amentum Holdings AMTM Stock Holding History

XTX Topco’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 		$1.09M Buy
52,938
+29,151
+123% +$705K 0.01% 1702
2026
Q1 		$620K Sell
23,787
-21,034
-47% -$660K 0.01% 1826
2025
Q4 		$1.3M Sell
44,821
-4,444
-9% -$114K 0.03% 844
2025
Q3 		$1.18M Sell
49,265
-15,458
-24% -$376K 0.06% 466
2025
Q2 		$1.53M Buy
+64,723
New +$1.35M 0.06% 444
2025
Q1 		– Sell
-90,065
Closed -$1.89M – 3250
2024
Q4 		$1.89M Buy
90,065
+82,673
+1,118% +$2.14M 0.16% 96
2024
Q3 		$238K Buy
+7,392
New +$211K 0.02% 1339

Other funds holding AMTM

AS
American Securities New York $3.75B AUM 23.12% 1-Year Est. Return
Invesco
Invesco Atlanta, Georgia $1.26T AUM 61.52% 1-Year Est. Return
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
Primecap Management
Primecap Management Pasadena, California $169B AUM 114.72% 1-Year Est. Return
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM
Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return
Dimensional Fund Advisors
Dimensional Fund Advisors Austin, Texas $552B AUM 44.19% 1-Year Est. Return
State Street
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

XTX Topco's AMTM Position: Q2 2026 in Review

XTX Topco increased its Amentum Holdings (AMTM) stake by 123% in Q2 2026, buying an estimated $705K and bringing the position to 52,938 shares worth $1.09M. The position accounts for 0.01% of the portfolio, ranked #1702.

XTX Topco first reported a position in AMTM in Q3 2024 and has held it in 7 quarters since. The position peaked at $1.89M in Q4 2024. 464 funds tracked by Wall St. Rank hold AMTM as of Q2 2026.

  • XTX Topco held 52,938 shares of Amentum Holdings worth $1.09M as of Q2 2026.
  • XTX Topco bought 29,151 Amentum Holdings shares in Q2 2026, an estimated $705K.
  • Amentum Holdings made up 0.01% of XTX Topco's portfolio in Q2 2026, its #1702 holding.
  • XTX Topco first reported a position in Amentum Holdings in Q3 2024 and has held it in 7 quarters since.
  • XTX Topco's Amentum Holdings position peaked at $1.89M in Q4 2024.
  • 464 funds tracked by Wall St. Rank held Amentum Holdings as of Q2 2026.

Based on XTX Topco's 13F filing for Q2 2026, filed 14 Aug 2026.