Simplex Trading
CSTL icon

Simplex Trading’s Castle Biosciences CSTL Stock Holding History

Simplex Trading’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
2025
Q4 		– Sell
-200
Closed -$4K – 8801
2025
Q3 		$4K Hold
200
– – ﹤0.01% 8388
2025
Q2 		$4K Buy
200
+100
+100% +$1.85K ﹤0.01% 7823
2025
Q1 		$2K Sell
100
-800
-89% -$19.8K ﹤0.01% 7953
2024
Q4 		$23K Sell
900
-900
-50% -$27.4K ﹤0.01% 6564
2024
Q3 		$51K Buy
+1,800
New +$45.8K ﹤0.01% 5856
2024
Q2 		– Sell
-200
Closed -$4K – 8931
2024
Q1 		$4K Hold
200
– – ﹤0.01% 8099
2023
Q4 		$4K Sell
200
-1,600
-89% -$28.2K ﹤0.01% 7950
2023
Q3 		$30K Sell
1,800
-700
-28% -$12.2K ﹤0.01% 6250
2023
Q2 		$34K Buy
+2,500
New +$50.7K ﹤0.01% 6211
2023
Q1 		– Sell
-400
Closed -$9K – 9173
2022
Q4 		$9K Hold
400
– – ﹤0.01% 7611
2022
Q3 		$10K Buy
+400
New +$11.2K ﹤0.01% 8223
2022
Q2 		– Sell
-200
Closed -$8K – 10107
2022
Q1 		$8K Hold
200
– – ﹤0.01% 9041
2021
Q4 		$8K Sell
200
-400
-67% -$20.9K ﹤0.01% 9180
2021
Q3 		$42K Hold
600
– – ﹤0.01% 7718
2021
Q2 		$43K Buy
600
+599
+59,900% +$39.6K ﹤0.01% 7821
2021
Q1 		$6K Sell
1
-19
-95% -$1.43K ﹤0.01% 8133
2020
Q4 		$134K Hold
20
– – ﹤0.01% 5121
2020
Q3 		$102K Hold
20
– – ﹤0.01% 4886
2020
Q2 		$75K Buy
+20
New +$683 ﹤0.01% 5094

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

Simplex Trading's CSTL Position: Q4 2025 in Review

Simplex Trading sold out of Castle Biosciences (CSTL) in Q4 2025, closing a stake of 1,512 shares — an estimated $48.7K sold.

Simplex Trading first reported a position in CSTL in Q2 2020 and held it in 14 quarters. The position peaked at $342K in Q3 2024. 194 funds tracked by Wall St. Rank hold CSTL as of Q4 2025.

  • Simplex Trading reported no remaining Castle Biosciences position as of Q4 2025 after selling out during the quarter.
  • Simplex Trading sold 1,512 Castle Biosciences shares in Q4 2025, an estimated $48.7K.
  • Simplex Trading first reported a position in Castle Biosciences in Q2 2020 and held it in 14 quarters.
  • Simplex Trading's Castle Biosciences position peaked at $342K in Q3 2024.
  • 194 funds tracked by Wall St. Rank held Castle Biosciences as of Q4 2025.

Based on Simplex Trading's 13F filing for Q4 2025, filed 11 Feb 2026.