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Mountaineer Partners Management’s ATI ATI Stock Holding History

Mountaineer Partners Management’s Portfolio ATI Stock Details ATI Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q2 		$11.9M Sell
60,419
-31,365
-34% -$5.32M 8.66% 6
2026
Q1 		$13.4M Sell
91,784
-37,125
-29% -$5.17M 6.63% 8
2025
Q4 		$14.8M Sell
128,909
-15,111
-10% -$1.47M 8.28% 3
2025
Q3 		$11.7M Buy
144,020
+21,050
+17% +$1.71M 6.81% 5
2025
Q2 		$10.6M Sell
122,970
-58,405
-32% -$4M 7.02% 8
2025
Q1 		$9.44M Sell
181,375
-1,295
-0.7% -$73.5K 9.03% 4
2024
Q4 		$10.1M Buy
182,670
+42,020
+30% +$2.48M 7.36% 3
2024
Q3 		$9.41M Sell
140,650
-68,423
-33% -$4.25M 5.87% 10
2024
Q2 		$11.6M Sell
209,073
-27,323
-12% -$1.53M 6.03% 4
2024
Q1 		$12.1M Sell
236,396
-15,443
-6% -$698K 5.58% 7
2023
Q4 		$11.5M Buy
251,839
+1,879
+0.8% +$78K 5.82% 8
2023
Q3 		$10.3M Buy
249,960
+1,131
+0.5% +$50.3K 6.59% 6
2023
Q2 		$11M Buy
+248,829
New +$9.52M 6.07% 5
2023
Q1 		– Sell
-195,589
Closed -$5.84M – 14
2022
Q4 		$5.84M Sell
195,589
-14,918
-7% -$437K 5.54% 8
2022
Q3 		$5.6M Hold
210,507
– – 7.08% 4
2022
Q2 		$4.78M Hold
210,507
– – 4.81% 6
2022
Q1 		$5.65M Sell
210,507
-448,877
-68% -$10.4M 3.11% 13
2021
Q4 		$10.5M Buy
659,384
+97,102
+17% +$1.56M 5.71% 11
2021
Q3 		$9.35M Buy
562,282
+125,443
+29% +$2.37M 6.11% 11
2021
Q2 		$9.11M Sell
436,839
-400
-0.1% -$9.17K 6.63% 11
2021
Q1 		$9.21M Buy
437,239
+7,097
+2% +$139K 6.45% 9
2020
Q4 		$7.21M Buy
430,142
+100,000
+30% +$1.27M 5.18% 15
2020
Q3 		$2.88M Hold
330,142
– – 2.49% 14
2020
Q2 		$3.36M Sell
330,142
-8,291
-2% -$71.9K 4.52% 11
2020
Q1 		$2.88M Buy
338,433
+22,900
+7% +$366K 4.09% 10
2019
Q4 		$6.52M Sell
315,533
-50,400
-14% -$1.09M 7.26% 8
2019
Q3 		$7.41M Sell
365,933
-120,000
-25% -$2.54M 7.46% 8
2019
Q2 		$12.2M Buy
485,933
+48,800
+11% +$1.19M 5.65% 4
2019
Q1 		$11.2M Sell
437,133
-34,500
-7% -$909K 9.54% 3
2018
Q4 		$10.3M Buy
+471,633
New +$12.2M 8.73% 4

Other funds holding ATI

BlackRock
BlackRock New York $6.73T AUM 46.02% 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
Capital World Investors
Capital World Investors Los Angeles, California $846B AUM 46.74% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return
Capital Research Global Investors
Capital Research Global Investors Los Angeles, California $717B AUM 35.42% 1-Year Est. Return
Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return
Capital International Investors
Capital International Investors Los Angeles, California $484B AUM 34.9% 1-Year Est. Return
Invesco
Invesco Atlanta, Georgia $1.26T AUM 61.52% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.88T AUM 44.46% 1-Year Est. Return

Mountaineer Partners Management's ATI Position: Q2 2026 in Review

Mountaineer Partners Management reduced its ATI (ATI) stake by 34% in Q2 2026, selling an estimated $5.32M and leaving 60,419 shares worth $11.9M. The position accounts for 8.66% of the portfolio, ranked #6.

Mountaineer Partners Management first reported a position in ATI in Q4 2018 and has held it in 30 quarters since. The position peaked at $14.8M in Q4 2025. 793 funds tracked by Wall St. Rank hold ATI as of Q2 2026.

  • Mountaineer Partners Management held 60,419 shares of ATI worth $11.9M as of Q2 2026.
  • Mountaineer Partners Management sold 31,365 ATI shares in Q2 2026, an estimated $5.32M.
  • ATI made up 8.66% of Mountaineer Partners Management's portfolio in Q2 2026, its #6 holding.
  • Mountaineer Partners Management first reported a position in ATI in Q4 2018 and has held it in 30 quarters since.
  • Mountaineer Partners Management's ATI position peaked at $14.8M in Q4 2025.
  • 793 funds tracked by Wall St. Rank held ATI as of Q2 2026.

Based on Mountaineer Partners Management's 13F filing for Q2 2026, filed 13 Aug 2026.