William Blair Investment Management
KOS icon

William Blair Investment Management’s Kosmos Energy KOS Stock Holding History

William Blair Investment Management’s Portfolio KOS Stock Details KOS Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2025
Q2 		– Sell
-17,169,011
Closed -$39.1M – 444
2025
Q1 		$39.1M Sell
17,169,011
-1,574,723
-8% -$4.65M 0.11% 165
2024
Q4 		$64.1M Buy
18,743,734
+4,114,499
+28% +$15.7M 0.16% 133
2024
Q3 		$59M Buy
14,629,235
+1,008,381
+7% +$4.91M 0.15% 127
2024
Q2 		$75.5M Buy
13,620,854
+1,624,495
+14% +$9.47M 0.2% 122
2024
Q1 		$71.5M Sell
11,996,359
-197,987
-2% -$1.19M 0.18% 131
2023
Q4 		$81.8M Sell
12,194,346
-504,658
-4% -$3.53M 0.24% 118
2023
Q3 		$104M Buy
12,699,004
+2,559,942
+25% +$18.1M 0.35% 92
2023
Q2 		$60.7M Sell
10,139,062
-5,081,035
-33% -$33.1M 0.19% 126
2023
Q1 		$113M Buy
+15,220,097
New +$111M 0.39% 88

Other funds holding KOS

BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
Grantham, Mayo, Van Otterloo & Co (GMO)
Grantham, Mayo, Van Otterloo & Co (GMO) Boston, Massachusetts $44.4B AUM 36.05% 1-Year Est. Return
American Century Companies
American Century Companies Kansas City, Missouri $226B AUM 44.75% 1-Year Est. Return
Hotchkis & Wiley Capital Management
Hotchkis & Wiley Capital Management Los Angeles, California $34.3B AUM 22.63% 1-Year Est. Return
PCM
Patient Capital Management Baltimore, Maryland $3.05B AUM 42.09% 1-Year Est. Return
EPIM
Equinox Partners Investment Management Stamford, Connecticut $212M AUM 153.42% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return
Vanguard Group
Vanguard Group Malvern, Pennsylvania $6.9T AUM 27.45% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.88T AUM 44.46% 1-Year Est. Return
Dimensional Fund Advisors
Dimensional Fund Advisors Austin, Texas $552B AUM 44.19% 1-Year Est. Return

William Blair Investment Management's KOS Position: Q2 2025 in Review

William Blair Investment Management sold out of Kosmos Energy (KOS) in Q2 2025, closing a stake of 17,169,011 shares — an estimated $39.1M sold.

William Blair Investment Management first reported a position in KOS in Q1 2023 and held it in 9 quarters. The position peaked at $113M in Q1 2023. 226 funds tracked by Wall St. Rank hold KOS as of Q2 2025.

  • William Blair Investment Management reported no remaining Kosmos Energy position as of Q2 2025 after selling out during the quarter.
  • William Blair Investment Management sold 17,169,011 Kosmos Energy shares in Q2 2025, an estimated $39.1M.
  • William Blair Investment Management first reported a position in Kosmos Energy in Q1 2023 and held it in 9 quarters.
  • William Blair Investment Management's Kosmos Energy position peaked at $113M in Q1 2023.
  • 226 funds tracked by Wall St. Rank held Kosmos Energy as of Q2 2025.

Based on William Blair Investment Management's 13F filing for Q2 2025, filed 29 Jul 2025.