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
2026
Q1 		$68.7K Buy
2,800
+2,200
+367% +$72.1K ﹤0.01% 5508
2025
Q4 		$23.3K Buy
+600
New +$19.3K ﹤0.01% 6335
2025
Q2 		– Sell
-200
Closed -$4K – 8798
2025
Q1 		$4K Sell
200
-500
-71% -$12.4K ﹤0.01% 7645
2024
Q4 		$18K Sell
700
-1,000
-59% -$30.5K ﹤0.01% 6758
2024
Q3 		$48K Sell
1,700
-12,000
-88% -$305K ﹤0.01% 5914
2024
Q2 		$298K Buy
13,700
+11,200
+448% +$250K ﹤0.01% 4228
2024
Q1 		$55K Buy
2,500
+2,200
+733% +$47.9K ﹤0.01% 6175
2023
Q4 		$6K Buy
300
+100
+50% +$1.76K ﹤0.01% 7735
2023
Q3 		$3K Sell
200
-2,800
-93% -$49K ﹤0.01% 7872
2023
Q2 		$41K Buy
3,000
+2,200
+275% +$44.6K ﹤0.01% 6032
2023
Q1 		$18K Sell
800
-400
-33% -$9.77K ﹤0.01% 6999
2022
Q4 		$28K Sell
1,200
-36,500
-97% -$846K ﹤0.01% 6538
2022
Q3 		$983K Buy
37,700
+37,000
+5,286% +$1.04M ﹤0.01% 2656
2022
Q2 		$15K Sell
700
-2,600
-79% -$60.4K ﹤0.01% 7863
2022
Q1 		$148K Buy
+3,300
New +$136K ﹤0.01% 5602
2021
Q4 		– Sell
-700
Closed -$49K – 10595
2021
Q3 		$49K Hold
700
– – ﹤0.01% 7518
2021
Q2 		$51K Buy
700
+692
+8,650% +$45.7K ﹤0.01% 7617
2021
Q1 		$54K Buy
8
+4
+100% +$301 ﹤0.01% 6512
2020
Q4 		$26K Buy
4
+3
+300% +$163 ﹤0.01% 6777
2020
Q3 		$5K Buy
+1
New +$44 ﹤0.01% 7098

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.