CSTL Castle Biosciences, Inc.

NASDAQ
$32.33

Castle Biosciences, Inc. (CSTL) Hedge Fund Activity

This view isolates hedge funds from the broader institutional ownership shown on the Institutional tab. A pension fund tracking an index may have no view on a stock; when a hedge fund builds or exits a position, that decision can carry information. This page measures those changes. Positions as of June 30, 2026.

Based on quarterly 13F long-equity filings. Changes compare reported quarter-end positions; filings can be reported up to 45 days later and do not represent a fund's complete exposure.

Hedge fund breadth
-9.09
10 buyers / 12 sellers
MIXED
Funds compared
22
funds with comparable CSTL positions
18 current holders · 20 prior-quarter holders
Net share change
-1.09M
+820.2K added, -1.91M cut
Position activity
2 new 8 increased 8 reduced 4 exited

Most significant moves

Ranked by conviction, not size — how much of the fund's own book the position represents, how far it moved, and what kind of fund made it.

Fund Action Shares changed Change Est. value Portfolio wt. Score
Point72 Asset Management, L.P. New +357.3K — $8.5M 0.0% 61
Magnetar Capital Event Quant Sold Out -23.3K -100.0% $556.5K 0.0% 54
CITADEL ADVISORS LLC Quant Increased +144.4K +119.3% $3.4M 0.0% 54
Portolan Capital Management Long/Short Reduced -1.02M -75.6% $24.4M 0.3% 53
Quadrature Capital Quant New +10.2K — $242.7K 0.0% 52
ExodusPoint Capital Management Long/Short Quant Sold Out -32.6K -100.0% $777.7K 0.0% 52
Brevan Howard Capital Management Macro Sold Out -18.6K -100.0% $442.7K 0.0% 49
Graham Capital Management Quant Macro Sold Out -11.1K -100.0% $265.5K 0.0% 49
Tudor Investment Corporation Macro Reduced -208.5K -93.5% $5.0M 0.0% 48
Man Group Event Long/Short Increased +61.6K +130.7% $1.5M 0.0% 48

Most significant buyers

By move score, not size.

  • Point72 Asset Management, L.P. New · +357.3K
  • CITADEL ADVISORS LLC Increased · +144.4K
  • Quadrature Capital New · +10.2K
  • Man Group Increased · +61.6K
  • AQR Capital Management Increased · +101.7K

Most significant sellers

By move score, not size.

  • Magnetar Capital Sold Out · -23.3K
  • Portolan Capital Management Reduced · -1.02M
  • ExodusPoint Capital Management Sold Out · -32.6K
  • Brevan Howard Capital Management Sold Out · -18.6K
  • Graham Capital Management Sold Out · -11.1K

Hedge fund positions

Fund Tier Shares Previous Change Change % Portfolio wt. Action Score
Point72 Asset Management, L.P. 1 357.3K 0 +357.3K — 0.0% New 61
Magnetar Capital 2 0 23.3K -23.3K -100.0% 0.0% Sold Out 54
CITADEL ADVISORS LLC 1 265.4K 121.0K +144.4K +119.3% 0.0% Increased 54
Portolan Capital Management 3 328.8K 1.4M -1.02M -75.6% 0.3% Reduced 53
Quadrature Capital 3 10.2K 0 +10.2K — 0.0% New 52
ExodusPoint Capital Management 3 0 32.6K -32.6K -100.0% 0.0% Sold Out 52
Brevan Howard Capital Management 3 0 18.6K -18.6K -100.0% 0.0% Sold Out 49
Graham Capital Management 3 0 11.1K -11.1K -100.0% 0.0% Sold Out 49
Tudor Investment Corporation 2 14.5K 223.0K -208.5K -93.5% 0.0% Reduced 48
Man Group 3 108.8K 47.1K +61.6K +130.7% 0.0% Increased 48
AQR Capital Management 3 166.6K 64.9K +101.7K +156.7% 0.0% Increased 47
TWO SIGMA INVESTMENTS, LP 2 100.4K 248.8K -148.5K -59.7% 0.0% Reduced 43
D. E. Shaw & Co., Inc. 1 112.8K 212.0K -99.2K -46.8% 0.0% Reduced 40
MILLENNIUM MANAGEMENT LLC 2 205.4K 353.3K -148.0K -41.9% 0.0% Reduced 39
RENAISSANCE TECHNOLOGIES LLC 1 371.2K 532.8K -161.6K -30.3% 0.0% Reduced 37
Trexquant Investment 3 206.1K 130.4K +75.7K +58.0% 0.0% Increased 36
Quantbot Technologies 4 2.6K 22.1K -19.5K -88.2% 0.0% Reduced 36
RTW Investments 1 2.8M 2.8M +20.0K +0.7% 0.6% Increased 34
Schonfeld Strategic Advisors 3 19.9K 42.4K -22.5K -53.0% 0.0% Reduced 33
Engineers Gate 4 29.5K 18.3K +11.2K +61.5% 0.0% Increased 32
Y-Intercept 4 31.9K 23.5K +8.4K +35.8% 0.0% Increased 26
Qube Research & Technologies Ltd 2 589.3K 559.6K +29.7K +5.3% 0.0% Increased 25

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

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Hedge funds are identified from their 13F filings, which are due 45 days after quarter end and cover long U.S.-listed equity positions only. A fund's short book never appears, so a reduced position can mean a changed view or a changed hedge — the filing doesn't say which.