Renaissance Technologies (RenTech)'s CSTL Position Overview
Renaissance Technologies (RenTech) (via Renaissance Technologies LLC) currently holds 371,200 shares of Castle Biosciences, Inc. (CSTL) worth $8.85 M, representing 0.01% of the portfolio. First purchased in 2020-Q1, this long-term strategic position has been held for 25 quarters.
Based on 13F filings, Renaissance Technologies (RenTech) has maintained a strategic position in CSTL, demonstrating sustained confidence in this investment. Largest addition occurred in Q4 2024, adding 195,438 shares. Largest reduction occurred in Q2 2026, reducing 161,600 shares.
Analysis based on 13F filings available since 2013 Q2
Renaissance Technologies (RenTech)'s Castle Biosciences (CSTL) Holding Value Over Time
Track share changes against reported price movement
Quarterly Castle Biosciences (CSTL) Trades by Renaissance Technologies (RenTech)
| Report Date | Bought/Sold (Sh.) | % Change | Qtr. End Shares | Reported Price |
|---|---|---|---|---|
| Q2 2026 | -161,600 | Reduce 30.33% | 371,200 | $23.85 |
| Q1 2026 | +39,700 | Add 8.05% | 532,800 | $24.55 |
| Q4 2025 | -69,500 | Reduce 12.35% | 493,100 | $38.90 |
| Q3 2025 | -107,900 | Reduce 16.09% | 562,600 | $22.77 |
| Q2 2025 | -30,700 | Reduce 4.38% | 670,500 | $20.42 |
| Q1 2025 | +16,200 | Add 2.36% | 701,200 | $20.02 |
| Q4 2024 | +195,438 | Add 39.92% | 685,000 | $26.65 |
| Q3 2024 | +188,062 | Add 62.38% | 489,562 | $28.52 |
| Q2 2024 | +96,800 | Add 47.29% | 301,500 | $21.77 |
| Q1 2024 | +92,300 | Add 82.12% | 204,700 | $22.15 |
| Q4 2023 | +5,600 | Add 5.24% | 112,400 | $21.58 |
| Q3 2023 | -65,600 | Reduce 38.05% | 106,800 | $16.89 |
| Q2 2023 | +136,000 | Add 373.63% | 172,400 | $0.01 |
| Q1 2023 | +14,300 | Add 64.71% | 36,400 | $0.02 |
| Q4 2022 | +5,100 | Add 30.00% | 22,100 | $0.02 |
| Q3 2022 | -400 | Reduce 2.30% | 17,000 | $26.06 |
| Q2 2022 | -7,600 | Reduce 30.40% | 17,400 | $21.95 |
| Q1 2022 | -109,281 | Reduce 81.38% | 25,000 | $44.88 |
| Q4 2021 | +134,281 | New Buy | 134,281 | $42.87 |
| Q2 2021 | -27,500 | Sold Out | 0 | $0.00 |
| Q1 2021 | +27,500 | New Buy | 27,500 | $68.47 |
| Q4 2020 | -3,900 | Sold Out | 0 | $0.00 |
| Q3 2020 | -38,936 | Reduce 90.90% | 3,900 | $51.54 |
| Q2 2020 | +9,636 | Add 29.02% | 42,836 | $37.68 |
| Q1 2020 | +33,200 | New Buy | 33,200 | $29.82 |
Renaissance Technologies (RenTech)'s Castle Biosciences Investment FAQs
Renaissance Technologies (RenTech) first purchased Castle Biosciences, Inc. (CSTL) in Q1 2020, acquiring 33,200 shares, as reported in their 13F filing for that period. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
Renaissance Technologies (RenTech) has held Castle Biosciences, Inc. (CSTL) for 25 quarters since Q1 2020.
Renaissance Technologies (RenTech)'s largest addition to Castle Biosciences, Inc. (CSTL) was in Q4 2024, adding 685,000 shares worth $18.26 M.
According to the latest 13F filing for Q2 2026, Renaissance Technologies (RenTech)'s firm, Renaissance Technologies LLC, owns 371,200 shares of Castle Biosciences, Inc. (CSTL), valued at approximately $8.85 M.
As of the Q2 2026 filing, Castle Biosciences, Inc. (CSTL) represents approximately 0.01% of Renaissance Technologies (RenTech)'s publicly disclosed stock portfolio, making it one of their key holdings.
Renaissance Technologies (RenTech)'s peak holding in Castle Biosciences, Inc. (CSTL) was 701,200 shares, as reported at the end of Q1 2025.