Castle Biosciences
CSTL • NASDAQ
Castle Biosciences is a medical - diagnostics & research company in the healthcare sector on NASDAQ, led by Derek J. Maetzold, with a market cap of $1.1B. As of Q3 2025, 91% of shares are held by 172 institutional investors, with BlackRock, Inc. as the largest holder at 11.0%.
CEODerek J. Maetzold
Market Cap$1.1B
Medical - Diagnostics & Research
Healthcare
Employees638.0
Websitecastlebiosciences.com
Country
United States of America
Overview
Overview of institutional ownership in CSTL as of Q3 2025 with a market cap of $660.5M
All Institutions
- Institutions
- 172
- Value Held
- $603.8M
- Shares Held
- 26.5M
- Avg Position
- $3.5M
- Median Position
- $394.7K
Hedge Funds
- Hedge Funds
- 29
- Value Held
- $147.9M
- Shares Held
- 6.5M
- Avg Position
- $5.1M
- Median Position
- $1.2M
Ownership Breakdown
Based on market cap of $660.5M as of Q3 2025. Institutional (non-HF) excludes hedge funds to avoid double counting.
Biggest Investors
Institutions with the largest positions in CSTL as of Q3 2025
| Institution | Position Value |
|---|---|
B BlackRock, Inc. Institution | $72.6M 0.00% of portfolio |
 VANGUARD GROUP INC Institution | $49.5M 0.00% of portfolio |
 PRINCIPAL FINANCIAL GROUP INC Institution | $40.9M 0.02% of portfolio |
 Portolan Capital Management, LLC Hedge Fund•Long/Short | $34.5M 1.87% of portfolio |
 DIMENSIONAL FUND ADVISORS LP Long Only Manager | $33.6M 0.01% of portfolio |
N Nuveen, LLC Institution | $21.8M 0.01% of portfolio |
B BRAIDWELL LP Hedge Fund•Multi-Strategy | $18.7M 0.76% of portfolio |
 STATE STREET CORP Institution | $16.5M 0.00% of portfolio |
A AIGH Capital Management LLC Hedge Fund•Long/Short | $16.1M 5.08% of portfolio |
 GEODE CAPITAL MANAGEMENT LLC ETF Provider | $15.9M 0.00% of portfolio |
Net Capital Flow
Institutional buying and selling activity for CSTL in Q3 2025
- Traded
- +$2.8M
- Buyers
- 98
- Sellers
- 66
- Total Bought
- +$73.2M
- Total Sold
- −$70.4M
- Avg Position
- $3.3M
Biggest Buyers
| Institution | Net Bought |
|---|---|
A AIGH Capital Management LLC Hedge Fund•Long/Short | +$16.1M +707.3K shares |
 SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC Hedge Fund•Long/Short | +$9.1M +400.0K shares |
 Point72 Asset Management, L.P. Hedge Fund•Multi-Strategy | +$7.7M +337.0K shares |
 Connor, Clark & Lunn Investment Management Ltd. Long Only Manager | +$4.8M +209.5K shares |
 MILLENNIUM MANAGEMENT LLC Hedge Fund•Multi-Strategy | +$3.3M +146.7K shares |
B BRIDGEWAY CAPITAL MANAGEMENT INC Long Only Manager | +$3.1M +136.4K shares |
 Parkman Healthcare Partners LLC Hedge Fund•Long/Short | +$2.8M +123.3K shares |
 MORGAN STANLEY RIA/Wealth | +$2.3M +102.0K shares |
DIMENSIONAL FUND ADVISORS LP Long Only Manager | +$2.2M +96.1K shares |
 SILVERCREST ASSET MANAGEMENT GROUP LLC RIA/Wealth | +$2.0M +87.9K shares |
Biggest Sellers
| Institution | Net Sold |
|---|---|
 CITADEL ADVISORS LLC Hedge Fund•Multi-Strategy | −$14.5M −637.6K shares |
 WASATCH ADVISORS INC Long Only Manager | −$8.7M −380.7K shares |
 WELLINGTON MANAGEMENT CO LLP Long Only Manager | −$8.3M −407.2K shares |
 SCHRODER INVESTMENT MANAGEMENT GROUP RIA/Wealth | −$3.4M −153.6K shares |
 Trexquant Investment LP Hedge Fund•Quant | −$3.2M −139.6K shares |
 ALGERT COLDIRON INVESTORS LLC Hedge Fund•Quant | −$2.9M −127.3K shares |
 AMERIPRISE FINANCIAL INC Institution | −$2.6M −116.2K shares |
N Nuveen, LLC Institution | −$2.6M −116.0K shares |
S Squarepoint Ops LLC Hedge Fund•Quant | −$2.6M −125.7K shares |
 RENAISSANCE TECHNOLOGIES LLC Hedge Fund•Quant | −$2.5M −107.9K shares |
Entry and Exit Activity
Institutions that initiated new positions or completely exited CSTL in Q3 2025
- New Positions
- 10
- New Value
- $27.1M
- Exited Positions
- 13
- Exited Value
- $14.4M
New Positions
| Institution | Position Value |
|---|---|
A AIGH Capital Management LLC Hedge Fund•Long/Short | $16.1M 707.3K shares |
SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC Hedge Fund•Long/Short | $9.1M 400.0K shares |
 SummitTX Capital, L.P. Hedge Fund•Multi-Strategy | $1.0M 45.0K shares |
 CAPSTONE INVESTMENT ADVISORS, LLC Hedge Fund•Multi-Strategy | $379.7K 16.7K shares |
 Glenmede Investment Management, LP Long Only Manager | $232.2K 10.2K shares |
 Atom Investors LP Hedge Fund•Market Neutral | $223.8K 9.8K shares |
S State of Alaska, Department of Revenue Institution | $35.4K 1.6K shares |
 FIRST HORIZON NATIONAL CORP RIA/Wealth | $10.2K 447.0 shares |
 Point72 Europe LLP Digital Asset Manager | $2.6K 112.0 shares |
O Optiver Holding B.V. Institution | $911.0 40.0 shares |
Exited Positions
| Institution | Previous Position |
|---|---|
WELLINGTON MANAGEMENT CO LLP Long Only Manager | $8.3M 407.2K shares |
S Squarepoint Ops LLC Hedge Fund•Quant | $2.6M 125.7K shares |
Y Y-Intercept Ltd Institution | $1.6M 78.9K shares |
X XTX Topco Ltd Institution | $945.5K 46.3K shares |
J Jump Financial, LLC Institution | $446.3K 21.9K shares |
 Advantage Alpha Capital Partners LP Hedge Fund•Market Neutral | $327.1K 16.0K shares |
 Mount Yale Investment Advisors, LLC RIA/Wealth | $170.8K 8.4K shares |
 RAYMOND JAMES FINANCIAL INC RIA/Wealth | $13.5K 662.0 shares |
 LAZARD ASSET MANAGEMENT LLC Long Only Manager | $1.0K 72.0 shares |
P Parkside Financial Bank & Trust Institution | $511.0 25.0 shares |
Options Activity
Institutions with the largest Call and Put options positions in CSTL as of Q3 2025
- Call Positions
- 2
- Call Value
- $960.9K
- Put Positions
- 1
- Put Value
- $211.8K
Call Positions
| Institution | Position Value |
|---|---|
CITADEL ADVISORS LLC Hedge Fund•Multi-Strategy | $553.3K 243.0 contracts |
J JANE STREET GROUP, LLC Institution | $407.6K 179.0 contracts |
Put Positions
| Institution | Position Value |
|---|---|
CITADEL ADVISORS LLC Hedge Fund•Multi-Strategy | $211.8K 93.0 contracts |
Most Committed Institutions
Institutions with CSTL as the highest % of their portfolio as of Q3 2025
| Institution | Portfolio Weight |
|---|---|
A AIGH Capital Management LLC Hedge Fund•Long/Short | 5.08% $16.1M |
B Birchview Capital, LP Hedge Fund•Value | 1.93% $2.5M |
Portolan Capital Management, LLC Hedge Fund•Long/Short | 1.87% $34.5M |
Parkman Healthcare Partners LLC Hedge Fund•Long/Short | 1.19% $10.8M |
B BRAIDWELL LP Hedge Fund•Multi-Strategy | 0.76% $18.7M |
 PERKINS CAPITAL MANAGEMENT INC RIA/Wealth | 0.56% $640.9K |
 PALISADE CAPITAL MANAGEMENT LLC/NJ Long Only Manager | 0.45% $14.5M |
SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC Hedge Fund•Long/Short | 0.29% $9.1M |
 Green Alpha Advisors, LLC Long Only Manager | 0.21% $217.2K |
 KORNITZER CAPITAL MANAGEMENT INC /KS Long Only Manager | 0.13% $6.3M |
Hedge Fund Spotlight
Discover hedge funds investing in CSTL
CAPSTONE INVESTMENT ADVISORS, LLC
Hedge Fund • Multi-Strategy
Portfolio ManagerPaul Matthew Britton
- Portfolio Value
- $9.4B
- Positions
- 1,012
- Last Reported
- Q3 2025
Sector Allocation
Position in Castle Biosciences
- Market Value
- $379.7K
- Shares Held
- 16.7K
- Portfolio Weight
- 0.00%
- Owned Since
- 2025-Q3
| Top Holding | Sector | Market Value | Weight |
|---|---|---|---|
Semiconductors Technology | $1.3B | 13.35% | |
Software - Infrastructure Technology | $1.1B | 11.84% | |
Specialty Retail Consumer Cyclical | $1.0B | 11.12% |
