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, Q1 2026
Institutional positions in Castle Biosciences Inc as of Mar 31, 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
- 186
- −7 vs. Q4 2025
- Shares held
- 27.6M
- +2.50M (+10.0%) vs. Q4 2025
- Total value
- $677.8M
- −$298.6M (−30.6%) vs. Q4 2025
- New holders
- 29
- 72 more added
- Sold out
- 36
- 61 more reduced
2 institutions that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q4 2025: 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, Q1 2026
Shares, value and share of portfolio for each institution holding Castle Biosciences Inc; share changes are against Q4 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| BlackRock, Inc. | 2,982,946 | $73.2M | 0.00% | −122,300−3.9% | Reduced |
| RTW Investments, LP | 2,758,335 | $67.7M | 0.67% | +643,098+30.4% | Added |
| Principal Financial Group Inc | 1,769,877 | $43.5M | 0.02% | −37,767−2.1% | Reduced |
| Portolan Capital Management, LLC | 1,350,283 | $33.1M | 1.76% | −379,180−21.9% | Reduced |
| Vanguard Capital Management LLC | 1,177,522 | $28.9M | 0.00% | +1,177,522 | New |
| Dimensional Fund Advisors LP | 1,039,761 | $25.5M | 0.01% | −104,038−9.1% | Reduced |
| Summit Partners Public Asset Management, LLC | 940,685 | $23.1M | 1.07% | −118,040−11.1% | Reduced |
| Vanguard Portfolio Management LLC | 861,771 | $21.2M | 0.00% | +861,771 | New |
| Allianz Asset Management GmbH | 811,324 | $19.9M | 0.02% | +189,025+30.4% | Added |
| State Street Corp | 769,079 | $18.9M | 0.00% | +32,625+4.4% | Added |
| Geode Capital Management, LLC | 728,100 | $17.9M | 0.00% | +13,187+1.8% | Added |
| AIGH Capital Management LLC | 590,601 | $14.5M | 2.97% | −34,118−5.5% | Reduced |
| Qube Research & Technologies Ltd | 559,583 | $13.7M | 0.02% | +324,065+137.6% | Added |
| Palisade Capital Management LLC | 535,884 | $13.2M | 0.44% | −31,893−5.6% | Reduced |
| Renaissance Technologies LLC | 532,800 | $13.1M | 0.02% | +39,700+8.1% | Added |
| Nuveen, LLC | 522,127 | $12.8M | 0.00% | −2,554−0.5% | Reduced |
| Acadian Asset Management LLC | 484,441 | $11.9M | 0.02% | +94,035+24.1% | Added |
| Wasatch Advisors Inc | 455,036 | $11.2M | 0.07% | −82,205−15.3% | Reduced |
| Morgan Stanley | 428,934 | $10.5M | 0.00% | +225,357+110.7% | Added |
| Eventide Asset Management, LLC | 386,425 | $9.49M | 0.16% | +81,425+26.7% | Added |
| Connor, Clark & Lunn Investment Management Ltd. | 377,082 | $9.26M | 0.02% | −11,409−2.9% | Reduced |
| Millennium Management LLC | 353,319 | $8.67M | 0.01% | +44,405+14.4% | Added |
| Goldman Sachs Group Inc | 341,171 | $8.38M | 0.00% | +53,936+18.8% | Added |
| Schroder Investment Management Group | 298,941 | $7.04M | 0.01% | −193,220−39.3% | Reduced |
| Northern Trust Corp | 273,101 | $6.70M | 0.00% | +10,858+4.1% | Added |
| Silvercrest Asset Management Group LLC | 268,535 | $6.59M | 0.05% | +63,533+31.0% | Added |
| Kornitzer Capital Management Inc | 264,396 | $6.49M | 0.14% | −3,337−1.2% | Reduced |
| Bridgeway Capital Management, LLC | 255,184 | $6.26M | 0.13% | +8,264+3.3% | Added |
| Two Sigma Investments, LP | 248,840 | $6.11M | 0.01% | +164,774+196.0% | Added |
| Advisors Capital Management, LLC | 248,376 | $6.10M | 0.07% | −2,301−0.9% | Reduced |
| SG Americas Securities, LLC | 244,886 | $6.01M | 0.01% | +223,624+1,051.8% | Added |
| Charles Schwab Investment Management Inc | 241,880 | $5.94M | 0.00% | −655−0.3% | Reduced |
| New York State Common Retirement Fund | 233,046 | $5.72M | 0.01% | 00.0% | Unchanged |
| Tudor Investment Corp Et Al | 222,982 | $5.47M | 0.03% | +55,804+33.4% | Added |
| Panagora Asset Management Inc | 222,353 | $5.46M | 0.02% | +176,358+383.4% | Added |
| D. E. Shaw & Co., Inc. | 211,966 | $5.20M | 0.00% | +52,257+32.7% | Added |
| Vanguard Fiduciary Trust Co | 188,211 | $4.62M | 0.00% | +188,211 | New |
| Allspring Global Investments Holdings, LLC | 160,663 | $3.94M | 0.01% | +1,492+0.9% | Added |
| Campbell & CO Investment Adviser LLC | 148,824 | $3.65M | 0.21% | +148,824 | New |
| Empowered Funds, LLC | 132,184 | $3.25M | 0.02% | +10,264+8.4% | Added |
| Trexquant Investment LP | 130,434 | $3.20M | 0.02% | +65,829+101.9% | Added |
| Parkman Healthcare Partners LLC | 126,150 | $3.10M | 0.32% | −24,408−16.2% | Reduced |
| BNP Paribas Arbitrage, SA | 122,156 | $3.00M | 0.00% | −27,855−18.6% | Reduced |
| Citadel Advisors LLC | 120,977 | $2.97M | 0.00% | −245,379−67.0% | Reduced |
| Franklin Resources Inc | 90,909 | $2.23M | 0.00% | +10,306+12.8% | Added |
| Bank of New York Mellon Corp | 88,654 | $2.18M | 0.00% | +1,670+1.9% | Added |
| JPMorgan Chase & Co | 88,771 | $2.09M | 0.00% | −1,261−1.4% | Reduced |
| American Century Companies Inc | 79,107 | $1.94M | 0.00% | +1,339+1.7% | Added |
| Brinker Capital Investments, LLC | 74,896 | $1.84M | 0.02% | +243+0.3% | Added |
| Mackenzie Financial Corp | 74,111 | $1.82M | 0.00% | +36,794+98.6% | Added |
| Bank of America Corp | 67,810 | $1.66M | 0.00% | −195,209−74.2% | Reduced |
| SummitTX Capital, L.P. | 67,033 | $1.65M | 0.05% | +49,623+285.0% | Added |
| UBS Asset Management Americas Inc | 64,964 | $1.59M | 0.00% | −4,664−6.7% | Reduced |
| AQR Capital Management LLC | 64,880 | $1.59M | 0.00% | +999+1.6% | Added |
| Envestnet Asset Management Inc | 61,865 | $1.52M | 0.00% | −101−0.2% | Reduced |
| Invesco Ltd. | 61,012 | $1.50M | 0.00% | −74,449−55.0% | Reduced |
| Swiss National Bank | 57,300 | $1.41M | 0.00% | 00.0% | Unchanged |
| FMR LLC | 50,412 | $1.24M | 0.00% | +8,126+19.2% | Added |
| UBS Group AG | 49,163 | $1.21M | 0.00% | −92,710−65.3% | Reduced |
| Man Group plc | 47,138 | $1.16M | 0.00% | +35,553+306.9% | Added |
| Formula Growth Ltd | 46,000 | $1.13M | 0.51% | +46,000 | New |
| Quantinno Capital Management LP | 45,476 | $1.12M | 0.00% | +36,144+387.3% | Added |
| Jane Street Group, LLC | 42,562 | $1.04M | 0.00% | −126,084−74.8% | Reduced |
| Schonfeld Strategic Advisors LLC | 42,413 | $1.04M | 0.01% | +20,937+97.5% | Added |
| Alliancebernstein L.P. | 25,270 | $983.0K | 0.00% | 00.0% | Unchanged |
| Rhumbline Advisers | 38,378 | $942.2K | 0.00% | −90−0.2% | Reduced |
| Price T Rowe Associates Inc | 37,792 | $928.0K | 0.00% | +3,654+10.7% | Added |
| KBC Group NV | 36,932 | $907.0K | 0.00% | +36,932 | New |
| Nomura Holdings Inc | 35,748 | $877.6K | 0.01% | +35,748 | New |
| SEI Investments Co | 35,046 | $860.4K | 0.00% | −4,681−11.8% | Reduced |
| Algert Global LLC | 34,778 | $853.8K | 0.01% | +15,800+83.3% | Added |
| Universal- Beteiligungs- und Servicegesellschaft mbH | 34,387 | $844.2K | 0.00% | +5,030+17.1% | Added |
| ExodusPoint Capital Management, LP | 32,608 | $800.5K | 0.01% | +32,608 | New |
| CI Private Wealth, LLC | 31,870 | $782.4K | 0.00% | +31,870 | New |
| California State Teachers Retirement System | 27,513 | $675.4K | 0.00% | −212−0.8% | Reduced |
| Arrowstreet Capital, Limited Partnership | 27,142 | $666.3K | 0.00% | +20,113+286.1% | Added |
| Barclays PLC | 26,810 | $658.2K | 0.00% | −45,339−62.8% | Reduced |
| Harbor Capital Advisors, Inc. | 25,614 | $629.0K | 0.05% | +12,182+90.7% | Added |
| Fox Run Management, L.L.C. | 26,247 | $618.1K | 0.11% | +4,363+19.9% | Added |
| STRS Ohio | 25,000 | $613.8K | 0.00% | +12,400+98.4% | Added |
| Deutsche Bank AG | 24,164 | $593.2K | 0.00% | +1,780+8.0% | Added |
| Truist Financial Corp | 23,781 | $583.8K | 0.00% | +153+0.6% | Added |
| Y-Intercept (Hong Kong) Ltd | 23,501 | $577.0K | 0.01% | +10,255+77.4% | Added |
| Magnetar Financial LLC | 23,332 | $572.8K | 0.01% | +23,332 | New |
| Legal & General Group Plc | 23,184 | $569.2K | 0.00% | −6,551−22.0% | Reduced |
| Quantbot Technologies LP | 22,060 | $541.6K | 0.02% | +22,013+46,836.2% | Added |
| CWM Advisors, LLC | 21,045 | $516.7K | 0.03% | +9,034+75.2% | Added |
| XTX Topco Ltd | 20,283 | $497.9K | 0.01% | −1,842−8.3% | Reduced |
| Brevan Howard Capital Management LP | 18,560 | $455.6K | 0.00% | +18,560 | New |
| Engineers Gate Manager LP | 18,256 | $448.2K | 0.01% | −4,693−20.4% | Reduced |
| Vanguard Asset Management, Ltd | 17,653 | $433.4K | 0.00% | +17,653 | New |
| MetLife Investment Management | 16,722 | $410.5K | 0.00% | +841+5.3% | Added |
| First Bank & Trust | 16,504 | $405.2K | 0.07% | −202−1.2% | Reduced |
| Dynamic Technology Lab Private Ltd | 15,913 | $390.7K | 0.06% | +15,913 | New |
| HRT Financial LP | 15,858 | $389.0K | 0.00% | −31,796−66.7% | Reduced |
| Diversify Wealth Management, LLC | 15,760 | $382.0K | 0.01% | +4,172+36.0% | Added |
| Perkins Capital Management Inc | 15,415 | $378.4K | 0.35% | −12,630−45.0% | Reduced |
| Janus Henderson Group PLC | 15,037 | $369.1K | 0.00% | 00.0% | Unchanged |
| Zurcher Kantonalbank (Zurich Cantonalbank) | 15,028 | $368.9K | 0.00% | +3,218+27.2% | Added |
| Summit Global Investments | 13,718 | $337.0K | 0.02% | +1,353+10.9% | Added |