6CM
AMTM

683 Capital Management’s Amentum Holdings AMTM Stock Holding History

683 Capital Management’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
2025
Q2 		– Sell
-100,000
Closed -$1.82M – 162
2025
Q1 		$1.82M Buy
+100,000
New +$2.04M 0.13% 109

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

683 Capital Management's AMTM Position: Q2 2026 in Review

683 Capital Management increased its Amentum Holdings (AMTM) stake by 42% in Q2 2026, buying an estimated $7.86M and bringing the position to 1,100,000 shares worth $22.7M. The position accounts for 1.12% of the portfolio, ranked #24.

683 Capital Management first reported a position in AMTM in Q4 2024 and has held it in 7 quarters since. The position peaked at $38.5M in Q2 2025. 462 funds tracked by Wall St. Rank hold AMTM as of Q2 2026.

  • 683 Capital Management held 1,100,000 shares of Amentum Holdings worth $22.7M as of Q2 2026.
  • 683 Capital Management bought 325,000 Amentum Holdings shares in Q2 2026, an estimated $7.86M.
  • Amentum Holdings made up 1.12% of 683 Capital Management's portfolio in Q2 2026, its #24 holding.
  • 683 Capital Management first reported a position in Amentum Holdings in Q4 2024 and has held it in 7 quarters since.
  • 683 Capital Management's Amentum Holdings position peaked at $38.5M in Q2 2025.
  • 462 funds tracked by Wall St. Rank held Amentum Holdings as of Q2 2026.

Based on 683 Capital Management's 13F filing for Q2 2026, filed 14 Aug 2026.