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Equibles

CSTL

Castle Biosciences Inc

Company with tickers: CSTL

CIK
1447362
CUSIP
14843C105
Shares Outstanding
30,329,952
13F Activity (30d)
113 filings 110 filers

Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.

Holders: 187
Total Value: $679,713,738
Total Shares: 27,686,919
Showing 1–100 of 191 holdings by value · page 1 of 2

Institutional Ownership Trend

26 quarters

Holder Concentration

Across 187 13F filers · Δ vs Dec 31, 2025
Top Holder
10.8%
Sep 2023 → Mar 2026 · range 10.3% – 15.3%
−1.0 pts
Top 5
36.3%
Sep 2023 → Mar 2026 · range 33.7% – 45.9%
−5.2 pts
Top 10
52.2%
Sep 2023 → Mar 2026 · range 48.6% – 63.1%
−6.2 pts
HHI
406
Sep 2023 → Mar 2026 · range 362 – 592
Broadly held−90

Quarterly Activity

vs Dec 31, 2025
New
50
Increased
61
Decreased
52
Sold Out
36
Unchanged
24
Holder count: +14
Institutional value: -2.8%
Shares held: +54.0%

Top Buyers

vs Dec 31, 2025
Institution Added Now Holds Open
Large RTW INVESTMENTS, LP +643,098 2,758,335
Large Qube Research & Technologies Ltd +324,065 559,583
Large SG Americas Securities, LLC +223,624 244,886
Large Allianz Asset Management GmbH +189,025 811,324
Large PANAGORA ASSET MANAGEMENT INC +176,358 222,353

Top Sellers

vs Dec 31, 2025
Institution Sold Now Holds Open
Mid Portolan Capital Management, LLC −379,180 1,350,283
Mega CITADEL ADVISORS LLC −240,979 165,977
Mega BANK OF AMERICA CORP /DE/ −195,209 67,810
Mega SCHRODER INVESTMENT MANAGEMENT GROUP −193,220 298,941
Mid SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC −118,040 940,685

Top New Positions

vs Dec 31, 2025
Institution Acquired Value (USD) Open
Mega BlackRock, Inc. 2,982,946 $73,231,316
Mega VANGUARD CAPITAL MANAGEMENT LLC 1,177,522 $28,908,165
Mega DIMENSIONAL FUND ADVISORS LP 1,039,761 $25,526,130
Mega VANGUARD PORTFOLIO MANAGEMENT LLC 861,771 $21,156,478
Large WASATCH ADVISORS LP 455,036 $11,171,133

Top Sold-Out Positions

vs Dec 31, 2025
Institution Previously Held Last Value (USD) Open
Mid BRAIDWELL LP 177,183 $6,892,418
Large Point72 Asset Management, L.P. 119,458 $4,646,916
Small Informed Momentum Co LLC 74,138 $2,883,968
Large Squarepoint Ops LLC 55,118 $2,144,090
Mega AMERIPRISE FINANCIAL INC 35,368 $1,375,814
Filter: New 50 Increased 61 Reduced 52 Sold out 36 Unchanged 24
Showing 100 of 191
All Common Calls Puts
Export CSV
Holder Value (USD) % of 13F Shares Open
Mega BlackRock, Inc. $73,231,316 10.77% 2,982,946
Large RTW INVESTMENTS, LP $67,717,124 9.96% 2,758,335
Mega PRINCIPAL FINANCIAL GROUP INC $43,450,479 6.39% 1,769,877
Mid Portolan Capital Management, LLC $33,149,447 4.88% 1,350,283
Mega VANGUARD CAPITAL MANAGEMENT LLC $28,908,165 4.25% 1,177,522
Mega DIMENSIONAL FUND ADVISORS LP $25,526,130 3.76% 1,039,761
Mid SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC $23,093,816 3.40% 940,685
Mega VANGUARD PORTFOLIO MANAGEMENT LLC $21,156,478 3.11% 861,771
Large Allianz Asset Management GmbH $19,918,003 2.93% 811,324
Mega STATE STREET CORP $18,880,889 2.78% 769,079
Mega GEODE CAPITAL MANAGEMENT, LLC $17,874,854 2.63% 728,100
Small AIGH Capital Management LLC $14,499,254 2.13% 590,601
Large Qube Research & Technologies Ltd $13,737,762 2.02% 559,583
Mid PALISADE CAPITAL MANAGEMENT, LP $13,155,952 1.94% 535,884
Large RENAISSANCE TECHNOLOGIES LLC $13,080,240 1.92% 532,800
Mega Nuveen, LLC $12,818,217 1.89% 522,127
Large ACADIAN ASSET MANAGEMENT LLC $11,893,026 1.75% 484,441
Large WASATCH ADVISORS LP $11,171,133 1.64% 455,036
Mega MORGAN STANLEY $10,530,326 1.55% 428,934
Mid EVENTIDE ASSET MANAGEMENT, LLC $9,486,733 1.40% 386,425
Large Connor, Clark & Lunn Investment Management Ltd. $9,257,363 1.36% 377,082
Mega MILLENNIUM MANAGEMENT LLC $8,673,981 1.28% 353,319
Mega GOLDMAN SACHS GROUP INC $8,375,747 1.23% 341,171
Mega SCHRODER INVESTMENT MANAGEMENT GROUP $7,339,001 1.08% 298,941
Mega NORTHERN TRUST CORP Bank $6,704,627 0.99% 273,101
Large SILVERCREST ASSET MANAGEMENT GROUP LLC $6,592,534 0.97% 268,535
Mid KORNITZER CAPITAL MANAGEMENT INC /KS $6,490,921 0.95% 264,396
Mid BRIDGEWAY CAPITAL MANAGEMENT, LLC $6,264,767 0.92% 255,184
Mega TWO SIGMA INVESTMENTS, LP $6,109,022 0.90% 248,840
Mid Advisors Capital Management, LLC $6,097,630 0.90% 248,376
Large SG Americas Securities, LLC Broker-Dealer $6,011,951 0.88% 244,886
Mega CHARLES SCHWAB INVESTMENT MANAGEMENT INC $5,938,154 0.87% 241,880
Large NEW YORK STATE COMMON RETIREMENT FUND Pension $5,721,279 0.84% 233,046
Large TUDOR INVESTMENT CORP ET AL $5,474,208 0.81% 222,982
Large PANAGORA ASSET MANAGEMENT INC $5,458,766 0.80% 222,353
Mega D. E. Shaw & Co., Inc. $5,203,765 0.77% 211,966
Mega VANGUARD FIDUCIARY TRUST CO Bank $4,620,580 0.68% 188,211
Large Allspring Global Investments Holdings, LLC $3,944,276 0.58% 160,663
Mid Campbell & CO Investment Adviser LLC $3,653,629 0.54% 148,824
Large Empowered Funds, LLC $3,245,117 0.48% 132,184
Large Trexquant Investment LP $3,202,154 0.47% 130,434
Small Parkman Healthcare Partners LLC $3,096,982 0.46% 126,150
Mega BNP PARIBAS ARBITRAGE, SA $2,998,929 0.44% 122,156
Mega CITADEL ADVISORS LLC $2,969,984 0.44% 120,977
Mega FRANKLIN RESOURCES INC $2,231,814 0.33% 90,909
Mega JPMORGAN CHASE & CO $2,179,325 0.32% 88,771
Mega Bank of New York Mellon Corp Bank $2,176,454 0.32% 88,654
Mega AMERICAN CENTURY COMPANIES INC $1,942,076 0.29% 79,107
Mid Orion Porfolio Solutions, LLC $1,838,696 0.27% 74,896
Large MACKENZIE FINANCIAL CORP $1,819,425 0.27% 74,111
Mega BANK OF AMERICA CORP /DE/ Bank $1,664,735 0.24% 67,810
Mid SummitTX Capital, L.P. $1,645,660 0.24% 67,033
Mega UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC $1,594,864 0.23% 64,964
Mega AQR CAPITAL MANAGEMENT LLC $1,592,801 0.23% 64,880
Mega ENVESTNET ASSET MANAGEMENT INC $1,518,785 0.22% 61,865
Mega Invesco Ltd. $1,497,843 0.22% 61,012
Mega Swiss National Bank Bank $1,406,715 0.21% 57,300
Mega FMR LLC $1,237,613 0.18% 50,412
Mega UBS Group AG $1,206,950 0.18% 49,163
Large Man Group plc $1,157,237 0.17% 47,138
Small FORMULA GROWTH LTD $1,129,300 0.17% 46,000
Large Quantinno Capital Management LP $1,116,435 0.16% 45,476
Mega JANE STREET GROUP, LLC $1,044,896 0.15% 42,562
Large Schonfeld Strategic Advisors LLC $1,041,239 0.15% 42,413
Mega RHUMBLINE ADVISERS $942,179 0.14% 38,378
Mega PRICE T ROWE ASSOCIATES INC /MD/ $927,793 0.14% 37,792
Large KBC Group NV $906,680 0.13% 36,932
Large NOMURA HOLDINGS INC $877,613 0.13% 35,748
Large SEI INVESTMENTS CO $860,378 0.13% 35,046
Mid ALGERT GLOBAL LLC $853,799 0.13% 34,778
Large Universal- Beteiligungs- und Servicegesellschaft mbH $844,200 0.12% 34,387
Large ExodusPoint Capital Management, LP $800,526 0.12% 32,608
Mega CITADEL ADVISORS LLC $797,875 0.12% 32,500
Large Corient Private Wealth LLC $782,408 0.12% 31,870
Large CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM Pension $675,444 0.10% 27,513
Mega ARROWSTREET CAPITAL, LIMITED PARTNERSHIP $666,336 0.10% 27,142
Mega BARCLAYS PLC $658,184 0.10% 26,810
Small FOX RUN MANAGEMENT, L.L.C. $644,363 0.09% 26,247
Mid HARBOR CAPITAL ADVISORS, INC. $628,823 0.09% 25,614
Mega ALLIANCEBERNSTEIN L.P. $620,378 0.09% 25,270
Large STRS OHIO $613,750 0.09% 25,000
Mega DEUTSCHE BANK AG\ Bank $593,226 0.09% 24,164
Large TRUIST FINANCIAL CORP $583,823 0.09% 23,781
Mid Y-Intercept (Hong Kong) Ltd $576,949 0.08% 23,501
Mid Magnetar Financial LLC $572,800 0.08% 23,332
Mega Legal & General Group Plc $569,166 0.08% 23,184
Mega JANE STREET GROUP, LLC $559,740 0.08% 22,800
Mid Quantbot Technologies LP $541,573 0.08% 22,060
Mid Inspire Investing, LLC $516,654 0.08% 21,045
Mid XTX Topco Ltd $497,947 0.07% 20,283
Mid Brevan Howard Capital Management LP $455,648 0.07% 18,560
Mid Engineers Gate Manager LP $448,184 0.07% 18,256
Mega VANGUARD ASSET MANAGEMENT, Ltd $433,381 0.06% 17,653
Large MetLife Investment Management, LLC $410,525 0.06% 16,722
Small First Bank & Trust Bank $405,173 0.06% 16,504
Small Dynamic Technology Lab Private Ltd $390,664 0.06% 15,913
Large HRT FINANCIAL LP $389,313 0.06% 15,858
Mid DIVERSIFY WEALTH MANAGEMENT, LLC $386,908 0.06% 15,760
Small PERKINS CAPITAL MANAGEMENT INC $378,438 0.06% 15,415
Mega JANUS HENDERSON GROUP PLC $369,158 0.05% 15,037

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