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.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 176 | $653.8M |
| Q1 2026 | 186 | $677.8M |
| Q4 2025 | 195 | $1.06B |
| Q3 2025 | 173 | $608.3M |
| Q2 2025 | 152 | $541.8M |
| Q1 2025 | 180 | $516.3M |
| Q4 2024 | 197 | $706.4M |
| Q3 2024 | 185 | $736.9M |
| Q2 2024 | 159 | $549.4M |
| Q1 2024 | 151 | $553.2M |
| Q4 2023 | 153 | $515.4M |
| Q3 2023 | 135 | $391.0M |
| Q2 2023 | 130 | $316.6M |
| Q1 2023 | 148 | $501.9M |
| Q4 2022 | 153 | $522.0M |
| Q3 2022 | 157 | $569.8M |
| Q2 2022 | 146 | $495.0M |
| Q1 2022 | 160 | $1.02B |
| Q4 2021 | 159 | $918.6M |
| Q3 2021 | 188 | $1.42B |
| Q2 2021 | 182 | $1.52B |
| Q1 2021 | 175 | $1.46B |
Institutions, Q2 2026
Shares, value and share of portfolio for each institution holding Castle Biosciences Inc; share changes are against Q1 2026.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| MAI Capital Management | 0 | $0 | 0.00% | −19−100.0% | Sold out |
| Missouri Trust & Investment Co | 0 | $0 | 0.00% | −19−100.0% | Sold out |
| Signature Equity Partners, LLC | 0 | $0 | 0.00% | −16−100.0% | Sold out |
| Wealth Preservation Advisors, LLC | 0 | $0 | 0.00% | −4−100.0% | Sold out |
| Larson Financial Group LLC | 0 | $0 | 0.00% | −1−100.0% | Sold out |
| Twin Peaks Wealth Advisors, LLC | 0 | $0 | 0.00% | −1−100.0% | Sold out |
| Janus Henderson Group PLC | – | – | – | – | Not filed |
| CWM, LLC | – | – | – | – | Not filed |
| Sunbelt Securities, Inc. | – | – | – | – | Not filed |