CSTL Castle Biosciences, Inc.

NASDAQ
$32.33

Castle Biosciences, Inc. (CSTL) Institutional Ownership

What the institutions did with CSTL last quarter, from their 13F filings. Counting managers rather than shares is the point: a single index fund adding to a position tells you far less than four hundred separate managers all deciding to. Positions as reported for the quarter ended June 30, 2026.

Managers compared
202
filed both this quarter and last
Managers holding
172
-11 on the quarter
Buyers
99
19 opened new
Sellers
86
30 sold out entirely
Buyer share
53.5%
of managers who traded it
Breadth
+7.0
net buyers, as a share of those trading

Every manager below opens. Subscribers can see any firm's whole portfolio — every position, its weight, and what they bought, trimmed and exited last quarter.

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Ownership map

Each block is one manager, sized by shares held and colored by how much they moved the position last quarter. Green added, red cut, grey stood pat.

Cut Unchanged Added Color saturates at ±50%.

Largest holders

Manager Shares % of reported
BlackRock, Inc. 3.3M 12.0%
RTW INVESTMENTS, LP 2.8M 10.1%
PRINCIPAL FINANCIAL GROUP INC 1.7M 6.3%
VANGUARD CAPITAL MANAGEMENT LLC 1.2M 4.5%
ACADIAN ASSET MANAGEMENT LLC 918.7K 3.4%
Allianz Asset Management GmbH 879.3K 3.2%
VANGUARD PORTFOLIO MANAGEMENT LLC 840.8K 3.1%
SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC 824.9K 3.0%
STATE STREET CORP 822.1K 3.0%
GEODE CAPITAL MANAGEMENT, LLC 795.9K 2.9%
MACKENZIE FINANCIAL CORP 793.5K 2.9%
DIMENSIONAL FUND ADVISORS LP 791.1K 2.9%
Jefferies Financial Group Inc. 647.4K 2.4%
Qube Research & Technologies Ltd 589.3K 2.2%
AIGH Capital Management LLC 545.1K 2.0%
RENAISSANCE TECHNOLOGIES LLC 371.2K 1.4%
GOLDMAN SACHS GROUP INC 358.4K 1.3%
Point72 Asset Management, L.P. 357.3K 1.3%
KENNEDY CAPITAL MANAGEMENT LLC 348.4K 1.3%
Connor, Clark & Lunn Investment Management Ltd. 331.7K 1.2%
MORGAN STANLEY 329.7K 1.2%
Portolan Capital Management, LLC 328.8K 1.2%
PANAGORA ASSET MANAGEMENT INC 301.0K 1.1%
Allspring Global Investments Holdings, LLC 292.5K 1.1%
NORTHERN TRUST CORP 285.2K 1.0%

Largest changes

Manager Action Previous Current Change
Portolan Capital Management, LLC Reduced 1.4M 328.8K -1.0M
MACKENZIE FINANCIAL CORP Increased 74.1K 793.5K +719.4K
Jefferies Financial Group Inc. New 0 647.4K +647.4K
ACADIAN ASSET MANAGEMENT LLC Increased 484.4K 918.7K +434.2K
EVENTIDE ASSET MANAGEMENT, LLC Sold Out 386.4K 0 -386.4K
Point72 Asset Management, L.P. New 0 357.3K +357.3K
KENNEDY CAPITAL MANAGEMENT LLC New 0 348.4K +348.4K
BlackRock, Inc. Increased 3.0M 3.3M +309.0K
PALISADE CAPITAL MANAGEMENT, LP Reduced 535.9K 231.9K -304.0K
SCHRODER INVESTMENT MANAGEMENT GROUP Sold Out 298.9K 0 -298.9K
Nuveen, LLC Reduced 522.1K 231.7K -290.4K
DIMENSIONAL FUND ADVISORS LP Reduced 1.0M 791.1K -248.7K
SG Americas Securities, LLC Sold Out 244.9K 0 -244.9K
TUDOR INVESTMENT CORP ET AL Reduced 223.0K 14.5K -208.5K
WASATCH ADVISORS LP Reduced 455.0K 279.3K -175.7K
RENAISSANCE TECHNOLOGIES LLC Reduced 532.8K 371.2K -161.6K
TWO SIGMA INVESTMENTS, LP Reduced 248.8K 100.4K -148.5K
MILLENNIUM MANAGEMENT LLC Reduced 353.3K 205.4K -148.0K
FIRST TRUST ADVISORS LP New 0 145.1K +145.1K
CITADEL ADVISORS LLC Increased 121.0K 265.4K +144.4K
Campbell & CO Investment Adviser LLC Reduced 148.8K 16.5K -132.3K
Allspring Global Investments Holdings, LLC Increased 160.7K 292.5K +131.8K
SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC Reduced 940.7K 824.9K -115.8K
AQR CAPITAL MANAGEMENT LLC Increased 64.9K 166.6K +101.7K
HRT FINANCIAL LP Increased 15.9K 115.9K +100.0K
MORGAN STANLEY Reduced 428.9K 329.7K -99.3K
D. E. Shaw & Co., Inc. Reduced 212.0K 112.8K -99.2K
PANAGORA ASSET MANAGEMENT INC Increased 222.4K 301.0K +78.7K
Trexquant Investment LP Increased 130.4K 206.1K +75.7K
Allianz Asset Management GmbH Increased 811.3K 879.3K +67.9K
GEODE CAPITAL MANAGEMENT, LLC Increased 728.1K 795.9K +67.8K
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP Increased 27.1K 92.7K +65.6K
Man Group plc Increased 47.1K 108.8K +61.6K
STATE STREET CORP Increased 769.1K 822.1K +53.0K
BNP PARIBAS FINANCIAL MARKETS Reduced 122.2K 69.6K -52.6K
VANGUARD CAPITAL MANAGEMENT LLC Increased 1.2M 1.2M +49.0K
FORMULA GROWTH LTD Sold Out 46.0K 0 -46.0K
AIGH Capital Management LLC Reduced 590.6K 545.1K -45.5K
Connor, Clark & Lunn Investment Management Ltd. Reduced 377.1K 331.7K -45.4K
PRINCIPAL FINANCIAL GROUP INC Reduced 1.8M 1.7M -43.2K
UBS Group AG Increased 49.2K 89.4K +40.2K
SEI INVESTMENTS CO Increased 35.0K 74.4K +39.4K
NOMURA HOLDINGS INC Sold Out 35.7K 0 -35.7K
ALGERT GLOBAL LLC Increased 34.8K 70.5K +35.7K
BRIDGEWAY CAPITAL MANAGEMENT, LLC Reduced 255.2K 221.3K -33.8K
ExodusPoint Capital Management, LP Sold Out 32.6K 0 -32.6K
Corient Private Wealth LP Sold Out 31.9K 0 -31.9K
BANK OF AMERICA CORP /DE/ Increased 67.8K 98.7K +30.9K
Qube Research & Technologies Ltd Increased 559.6K 589.3K +29.7K
Quantinno Capital Management LP Reduced 45.5K 16.4K -29.0K
FOX RUN MANAGEMENT, L.L.C. Sold Out 26.2K 0 -26.2K
Magnetar Financial LLC Sold Out 23.3K 0 -23.3K
Schonfeld Strategic Advisors LLC Reduced 42.4K 19.9K -22.5K
Russell Investments Group, Ltd. Increased 9.3K 31.7K +22.4K
Tidal Investments LLC New 0 22.2K +22.2K
VANGUARD PORTFOLIO MANAGEMENT LLC Reduced 861.8K 840.8K -21.0K
RTW INVESTMENTS, LP Increased 2.8M 2.8M +20.0K
XTX Topco Ltd Increased 20.3K 39.9K +19.6K
Quantbot Technologies LP Reduced 22.1K 2.6K -19.5K
Parkman Healthcare Partners LLC Increased 126.2K 144.8K +18.6K

13F filings are due 45 days after quarter end and cover long positions in U.S.-listed equities only, so this is a lagged and partial picture: shorts, bonds and foreign listings never appear. Options positions are excluded here rather than folded into the share counts. Political ownership is coming.