Skip to main content

Castle Biosciences Inc

CSTL
Exchange
Nasdaq
Industry
Services-Medical Laboratories
SEC CIK
0001447362

In the last 90 days, Castle Biosciences Inc insiders filed 0 open-market purchases and 20 sales; 176 institutions reported holding it in 13F filings for Q2 2026, worth $653.8M in total; no superinvestor holds it.

13F holders, Q2 2026

Institutional positions in Castle Biosciences Inc as of Jun 30, 2026. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works

Institutional holders
176
−7 vs. Q1 2026
Shares held
27.4M
−182.5K (−0.7%) vs. Q1 2026
Total value
$653.8M
−$23.5M (−3.5%) vs. Q1 2026
New holders
23
80 more added
Sold out
30
56 more reduced

3 institutions that held it in Q1 2026 haven't filed for Q2 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.

Compare with Q1 2026: new holders, sold out and not filed yet

Holders and value by quarter

Institutions reporting CSTL on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.

Institutional holdersQ2 2026: 176 institutions
Q1 2021: 175 institutionsQ2 2021: 182 institutionsQ3 2021: 188 institutionsQ4 2021: 159 institutionsQ1 2022: 160 institutionsQ2 2022: 146 institutionsQ3 2022: 157 institutionsQ4 2022: 153 institutionsQ1 2023: 148 institutionsQ2 2023: 130 institutionsQ3 2023: 135 institutionsQ4 2023: 153 institutionsQ1 2024: 151 institutionsQ2 2024: 159 institutionsQ3 2024: 185 institutionsQ4 2024: 197 institutionsQ1 2025: 180 institutionsQ2 2025: 152 institutionsQ3 2025: 173 institutionsQ4 2025: 195 institutionsQ1 2026: 186 institutionsQ2 2026: 176 institutions
Value heldQ2 2026: $653.8M
Q1 2021: $1.46BQ2 2021: $1.52BQ3 2021: $1.43BQ4 2021: $919.0MQ1 2022: $1.02BQ2 2022: $495.0MQ3 2022: $569.8MQ4 2022: $522.0MQ1 2023: $503.2MQ2 2023: $316.6MQ3 2023: $391.0MQ4 2023: $527.1MQ1 2024: $584.1MQ2 2024: $550.7MQ3 2024: $740.5MQ4 2024: $709.5MQ1 2025: $518.1MQ2 2025: $542.0MQ3 2025: $609.0MQ4 2025: $1.06BQ1 2026: $677.8MQ2 2026: $653.8M
Institutions holding CSTL and their total value by quarter
QuarterHoldersValue
Q2 2026176$653.8M
Q1 2026186$677.8M
Q4 2025195$1.06B
Q3 2025173$609.0M
Q2 2025152$542.0M
Q1 2025180$518.1M
Q4 2024197$709.5M
Q3 2024185$740.5M
Q2 2024159$550.7M
Q1 2024151$584.1M
Q4 2023153$527.1M
Q3 2023135$391.0M
Q2 2023130$316.6M
Q1 2023148$503.2M
Q4 2022153$522.0M
Q3 2022157$569.8M
Q2 2022146$495.0M
Q1 2022160$1.02B
Q4 2021159$919.0M
Q3 2021188$1.43B
Q2 2021182$1.52B
Q1 2021175$1.46B

Institutions, Q2 2026

Shares, value and share of portfolio for each institution holding Castle Biosciences Inc; share changes are against Q1 2026.

Institutions holding CSTL in Q2 2026
InstitutionSharesValue% of portfolioChange in sharesAction
BlackRock, Inc.3,291,963$78.5M0.00%+309,017+10.4%Added
RTW Investments, LP2,778,335$66.3M0.57%+20,000+0.7%Added
Principal Financial Group Inc1,726,648$41.2M0.02%−43,229−2.4%Reduced
Vanguard Capital Management LLC1,226,497$29.3M0.00%+48,975+4.2%Added
Acadian Asset Management LLC918,668$21.9M0.03%+434,227+89.6%Added
Allianz Asset Management GmbH879,258$21.0M0.02%+67,934+8.4%Added
Vanguard Portfolio Management LLC840,785$20.1M0.00%−20,986−2.4%Reduced
Summit Partners Public Asset Management, LLC824,872$19.7M0.51%−115,813−12.3%Reduced
State Street Corp822,079$19.6M0.00%+53,000+6.9%Added
Geode Capital Management, LLC795,912$19.0M0.00%+67,812+9.3%Added
Mackenzie Financial Corp793,507$18.9M0.02%+719,396+970.7%Added
Dimensional Fund Advisors LP791,085$18.9M0.00%−248,676−23.9%Reduced
Jefferies Financial Group Inc.647,391$15.4M0.14%+647,391New
Qube Research & Technologies Ltd589,300$14.1M0.02%+29,717+5.3%Added
AIGH Capital Management LLC545,101$13.0M1.18%−45,500−7.7%Reduced
Renaissance Technologies LLC371,200$8.85M0.01%−161,600−30.3%Reduced
Goldman Sachs Group Inc358,397$8.55M0.00%+17,226+5.0%Added
Point72 Asset Management, L.P.357,317$8.52M0.01%+357,317New
Kennedy Capital Management, Inc.348,371$8.31M0.15%+348,371New
Connor, Clark & Lunn Investment Management Ltd.331,727$7.91M0.01%−45,355−12.0%Reduced
Morgan Stanley329,684$7.86M0.00%−99,250−23.1%Reduced
Portolan Capital Management, LLC328,818$7.84M0.29%−1,021,465−75.6%Reduced
Panagora Asset Management Inc301,040$7.18M0.02%+78,687+35.4%Added
Allspring Global Investments Holdings, LLC292,470$6.98M0.01%+131,807+82.0%Added
Northern Trust Corp285,158$6.80M0.00%+12,057+4.4%Added
Wasatch Advisors Inc279,349$6.66M0.04%−175,687−38.6%Reduced
Citadel Advisors LLC265,353$6.33M0.00%+144,376+119.3%Added
Kornitzer Capital Management Inc264,235$6.30M0.13%−161−0.1%Reduced
Silvercrest Asset Management Group LLC256,095$6.11M0.04%−12,440−4.6%Reduced
Charles Schwab Investment Management Inc254,535$6.07M0.00%+12,655+5.2%Added
Advisors Capital Management, LLC238,204$5.68M0.06%−10,172−4.1%Reduced
New York State Common Retirement Fund234,746$5.60M0.01%+1,700+0.7%Added
Palisade Capital Management LLC231,931$5.53M0.24%−303,953−56.7%Reduced
Nuveen, LLC231,726$5.53M0.00%−290,401−55.6%Reduced
Bridgeway Capital Management, LLC221,338$5.28M0.09%−33,846−13.3%Reduced
Trexquant Investment LP206,111$4.92M0.03%+75,677+58.0%Added
Millennium Management LLC205,369$4.90M0.00%−147,950−41.9%Reduced
Vanguard Fiduciary Trust Co197,494$4.71M0.00%+9,283+4.9%Added
AQR Capital Management LLC166,567$3.97M0.00%+101,687+156.7%Added
First Trust Advisors LP145,064$3.46M0.00%+145,064New
Parkman Healthcare Partners LLC144,791$3.45M0.35%+18,641+14.8%Added
Empowered Funds, LLC142,338$3.39M0.02%+10,154+7.7%Added
HRT Financial LP115,853$2.76M0.01%+99,995+630.6%Added
D. E. Shaw & Co., Inc.112,789$2.69M0.00%−99,177−46.8%Reduced
Man Group plc108,761$2.59M0.00%+61,623+130.7%Added
Two Sigma Investments, LP100,374$2.39M0.00%−148,466−59.7%Reduced
Bank of America Corp98,745$2.36M0.00%+30,935+45.6%Added
Bank of New York Mellon Corp98,018$2.34M0.00%+9,364+10.6%Added
Franklin Resources Inc97,733$2.33M0.00%+6,824+7.5%Added
Arrowstreet Capital, Limited Partnership92,736$2.21M0.00%+65,594+241.7%Added
UBS Group AG89,368$2.13M0.00%+40,205+81.8%Added
JPMorgan Chase & Co84,804$2.06M0.00%−3,967−4.5%Reduced
SummitTX Capital, L.P.79,018$1.88M0.05%+11,985+17.9%Added
SEI Investments Co74,433$1.78M0.00%+39,387+112.4%Added
Algert Global LLC70,478$1.68M0.02%+35,700+102.7%Added
Brinker Capital Investments, LLC69,654$1.66M0.01%−5,242−7.0%Reduced
BNP Paribas Arbitrage, SA69,571$1.66M0.00%−52,585−43.0%Reduced
American Century Companies Inc65,413$1.56M0.00%−13,694−17.3%Reduced
UBS Asset Management Americas Inc64,346$1.53M0.00%−618−1.0%Reduced
Norges Bank60,100$1.43M0.00%+60,100New
FMR LLC55,871$1.33M0.00%+5,459+10.8%Added
Envestnet Asset Management Inc55,157$1.32M0.00%−6,708−10.8%Reduced
Invesco Ltd.54,888$1.31M0.00%−6,124−10.0%Reduced
Swiss National Bank53,700$1.28M0.00%−3,600−6.3%Reduced
Price T Rowe Associates Inc53,242$1.27M0.00%+15,450+40.9%Added
Jane Street Group, LLC44,793$1.07M0.00%+2,231+5.2%Added
XTX Topco Ltd39,923$952.2K0.01%+19,640+96.8%Added
Rhumbline Advisers39,010$930.4K0.00%+632+1.6%Added
California State Teachers Retirement System37,802$901.6K0.00%+10,289+37.4%Added
KBC Group NV36,042$860.0K0.00%−890−2.4%Reduced
Russell Investments Group, Ltd.31,679$761.4K0.00%+22,364+240.1%Added
Y-Intercept (Hong Kong) Ltd31,916$761.2K0.02%+8,415+35.8%Added
Harbor Capital Advisors, Inc.31,748$757.0K0.05%+6,134+23.9%Added
STRS Ohio30,500$727.4K0.00%+5,500+22.0%Added
Barclays PLC30,330$723.4K0.00%+3,520+13.1%Added
Deutsche Bank AG30,139$718.8K0.00%+5,975+24.7%Added
Wells Fargo & Company29,543$704.6K0.00%+16,651+129.2%Added
Engineers Gate Manager LP29,480$703.1K0.01%+11,224+61.5%Added
CWM Advisors, LLC29,047$692.8K0.03%+8,002+38.0%Added
Alliancebernstein L.P.27,100$665.3K0.00%+1,830+7.2%Added
Universal- Beteiligungs- und Servicegesellschaft mbH25,221$601.5K0.00%−9,166−26.7%Reduced
Truist Financial Corp23,786$567.3K0.00%+50.0%Added
Toroso Investments, LLC22,186$529.1K0.00%+22,186New
Legal & General Group Plc20,548$490.1K0.00%−2,636−11.4%Reduced
Schonfeld Strategic Advisors LLC19,930$475.3K0.00%−22,483−53.0%Reduced
First Bank & Trust18,591$443.4K0.07%+2,087+12.6%Added
Vanguard Asset Management, Ltd17,653$421.0K0.00%00.0%Unchanged
MetLife Investment Management17,008$405.6K0.00%+286+1.7%Added
Counterpoint Mutual Funds LLC16,510$393.8K0.04%+16,510New
Campbell & CO Investment Adviser LLC16,476$393.0K0.02%−132,348−88.9%Reduced
Quantinno Capital Management LP16,428$391.8K0.00%−29,048−63.9%Reduced
Diversify Wealth Management, LLC15,932$389.4K0.01%+172+1.1%Added
Diversify Advisory Services, LLC15,932$389.4K0.01%+15,932New
Citigroup Inc16,144$385.0K0.00%+12,117+300.9%Added
Perkins Capital Management Inc16,140$384.9K0.29%+725+4.7%Added
Zurcher Kantonalbank (Zurich Cantonalbank)15,579$371.6K0.00%+551+3.7%Added
Jupiter Topco LLC15,037$358.2K0.00%+15,037New
Tudor Investment Corp Et Al14,462$344.9K0.00%−208,520−93.5%Reduced
LPL Financial LLC14,220$339.1K0.00%+4,520+46.6%Added
Mirae Asset Global ETFs Holdings Ltd.13,785$328.8K0.00%+109+0.8%Added