SEI Investments
AMTM

SEI Investments’s Amentum Holdings AMTM Stock Holding History

SEI Investments’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 		$3.93M Sell
190,069
-104,599
-35% -$2.53M ﹤0.01% 1619
2026
Q1 		$7.69M Buy
294,668
+77,624
+36% +$2.44M 0.01% 1274
2025
Q4 		$6.29M Buy
217,044
+16,521
+8% +$422K 0.01% 1275
2025
Q3 		$4.8M Sell
200,523
-18,603
-8% -$453K 0.01% 1314
2025
Q2 		$5.17M Buy
219,126
+16,976
+8% +$355K 0.01% 1256
2025
Q1 		$3.68M Sell
202,150
-85,163
-30% -$1.73M ﹤0.01% 1394
2024
Q4 		$6.04M Buy
287,313
+43,597
+18% +$1.13M 0.01% 1211
2024
Q3 		$7.86M Buy
+243,716
New +$6.94M 0.01% 1084

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

SEI Investments's AMTM Position: Q2 2026 in Review

SEI Investments reduced its Amentum Holdings (AMTM) stake by 35% in Q2 2026, selling an estimated $2.53M and leaving 190,069 shares worth $3.93M. The position accounts for ﹤0.01% of the portfolio, ranked #1619.

SEI Investments first reported a position in AMTM in Q3 2024 and has held it in 8 quarters since. The position peaked at $7.86M in Q3 2024. 462 funds tracked by Wall St. Rank hold AMTM as of Q2 2026.

  • SEI Investments held 190,069 shares of Amentum Holdings worth $3.93M as of Q2 2026.
  • SEI Investments sold 104,599 Amentum Holdings shares in Q2 2026, an estimated $2.53M.
  • Amentum Holdings made up ﹤0.01% of SEI Investments's portfolio in Q2 2026, its #1619 holding.
  • SEI Investments first reported a position in Amentum Holdings in Q3 2024 and has held it in 8 quarters since.
  • SEI Investments's Amentum Holdings position peaked at $7.86M in Q3 2024.
  • 462 funds tracked by Wall St. Rank held Amentum Holdings as of Q2 2026.

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