RhumbLine Advisers
AMTM icon

RhumbLine Advisers’s Amentum Holdings AMTM Stock Holding History

RhumbLine Advisers’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
Q3 		$5.08M Sell
280,568
-3,492
-1% -$73.1K ﹤0.01% 1422
2026
Q2 		$5.87M Sell
284,060
-16,233
-5% -$393K ﹤0.01% 1386
2026
Q1 		$7.83M Buy
300,293
+8,852
+3% +$278K 0.01% 1185
2025
Q4 		$8.45M Buy
291,441
+1,623
+0.6% +$41.5K 0.01% 1141
2025
Q3 		$6.94M Buy
289,818
+2,571
+0.9% +$62.6K 0.01% 1261
2025
Q2 		$6.78M Sell
287,247
-22,856
-7% -$478K 0.01% 1253
2025
Q1 		$5.64M Buy
310,103
+14,919
+5% +$304K 0.01% 1296
2024
Q4 		$6.21M Buy
295,184
+73,326
+33% +$1.9M 0.01% 1320
2024
Q3 		$7.15M Buy
+221,858
New +$6.32M 0.01% 1235

Other funds holding AMTM

American Securities
American Securities New York $2.69B AUM 8.08% 1-Year Est. Return
Invesco
Invesco Atlanta, Georgia $1.27T AUM 50.62% 1-Year Est. Return
BlackRock
BlackRock New York $6.79T AUM 37.06% 1-Year Est. Return
Primecap Management
Primecap Management Pasadena, California $161B AUM 86.05% 1-Year Est. Return
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.21T AUM
Dimensional Fund Advisors
Dimensional Fund Advisors Austin, Texas $551B AUM 33.95% 1-Year Est. Return
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.76T AUM
Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.32T AUM 44.66% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $3.44T AUM 36.12% 1-Year Est. Return
Thompson Siegel & Walmsley
Thompson Siegel & Walmsley Richmond, Virginia $5.37B AUM 3.99% 1-Year Est. Return

RhumbLine Advisers's AMTM Position: Q3 2026 in Review

RhumbLine Advisers reduced its Amentum Holdings (AMTM) stake by 1.2% in Q3 2026, selling an estimated $73.1K and leaving 280,568 shares worth $5.08M. The position accounts for ﹤0.01% of the portfolio, ranked #1422.

RhumbLine Advisers first reported a position in AMTM in Q3 2024 and has held it in 9 quarters since. The position peaked at $8.45M in Q4 2025. 360 funds tracked by Wall St. Rank hold AMTM as of Q3 2026.

  • RhumbLine Advisers held 280,568 shares of Amentum Holdings worth $5.08M as of Q3 2026.
  • RhumbLine Advisers sold 3,492 Amentum Holdings shares in Q3 2026, an estimated $73.1K.
  • Amentum Holdings made up ﹤0.01% of RhumbLine Advisers's portfolio in Q3 2026, its #1422 holding.
  • RhumbLine Advisers first reported a position in Amentum Holdings in Q3 2024 and has held it in 9 quarters since.
  • RhumbLine Advisers's Amentum Holdings position peaked at $8.45M in Q4 2025.
  • 360 funds tracked by Wall St. Rank held Amentum Holdings as of Q3 2026.

Based on RhumbLine Advisers's 13F filing for Q3 2026, filed 10 Nov 2026.