XT
CSTL icon

XTX Topco’s Castle Biosciences CSTL Stock Holding History

XTX Topco’s Portfolio CSTL Stock Details CSTL Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$498K Sell
20,283
-1,842
-8% -$60.3K 0.01% 2059
2025
Q4 		$861K Buy
+22,125
New +$713K 0.02% 1138
2025
Q3 		– Sell
-46,301
Closed -$945K – 2685
2025
Q2 		$945K Buy
46,301
+26,673
+136% +$494K 0.04% 697
2025
Q1 		$393K Buy
+19,628
New +$486K 0.02% 1205
2024
Q3 		– Sell
-10,003
Closed -$218K – 2169
2024
Q2 		$218K Buy
+10,003
New +$223K 0.02% 1179
2024
Q1 		– Sell
-14,145
Closed -$305K – 1917
2023
Q4 		$305K Buy
+14,145
New +$249K 0.07% 602
2023
Q2 		– Sell
-16,254
Closed -$369K – 1480
2023
Q1 		$369K Buy
+16,254
New +$397K 0.08% 489

Other funds holding CSTL

BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
RI
RTW Investments New York $10B AUM 135.35% 1-Year Est. Return
Principal Financial Group
Principal Financial Group Des Moines, Iowa $187B AUM 18.48% 1-Year Est. Return
PCM
Portolan Capital Management Boston, Massachusetts $1.88B AUM 115.74% 1-Year Est. Return
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
Dimensional Fund Advisors
Dimensional Fund Advisors Austin, Texas $481B AUM 30.42% 1-Year Est. Return
SPPAM
Summit Partners Public Asset Management Boston, Massachusetts $3.72B AUM 162.29% 1-Year Est. Return
VPM
Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM
Allianz Asset Management
Allianz Asset Management Munich, Germany $95.4B AUM 38.74% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return

XTX Topco's CSTL Position: Q1 2026 in Review

XTX Topco reduced its Castle Biosciences (CSTL) stake by 8.3% in Q1 2026, selling an estimated $60.3K and leaving 20,283 shares worth $498K. The position accounts for 0.01% of the portfolio, ranked #2059.

XTX Topco first reported a position in CSTL in Q1 2023 and has held it in 7 quarters since. The position peaked at $945K in Q2 2025. 186 funds tracked by Wall St. Rank hold CSTL as of Q1 2026.

  • XTX Topco held 20,283 shares of Castle Biosciences worth $498K as of Q1 2026.
  • XTX Topco sold 1,842 Castle Biosciences shares in Q1 2026, an estimated $60.3K.
  • Castle Biosciences made up 0.01% of XTX Topco's portfolio in Q1 2026, its #2059 holding.
  • XTX Topco first reported a position in Castle Biosciences in Q1 2023 and has held it in 7 quarters since.
  • XTX Topco's Castle Biosciences position peaked at $945K in Q2 2025.
  • 186 funds tracked by Wall St. Rank held Castle Biosciences as of Q1 2026.

Based on XTX Topco's 13F filing for Q1 2026, filed 15 May 2026.