Castle Biosciences, Inc.
US ˙ NasdaqGM ˙ US14843C1053

SecurityCSTL / Castle Biosciences, Inc.
InstitutionEngineers Gate Manager LP
Latest Disclosed Ownership18,256 shares
Latest Disclosed Value $ 448,185
Engineers Gate Manager LP reports 20.45% decrease in ownership of CSTL / Castle Biosciences, Inc.

On May 15, 2026 - Engineers Gate Manager LP filed a 13F-HR form disclosing ownership of 18,256 shares of Castle Biosciences, Inc. (US:CSTL) valued at $448,185 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 22,949 shares of Castle Biosciences, Inc.. This represents a change in shares of -20.45% during the quarter. The current value of the position is $372,240 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F CASTLE BIOSCIENCES COM 14843C105 18,256 -4,693 -20.45 448 -49.78 0.0056
2026-02-17 2025-12-31 13F CASTLE BIOSCIENCES COM 14843C105 22,949 -23,557 -50.65 893 -15.69 0.0106
2025-11-14 2025-09-30 13F CASTLE BIOSCIENCES COM 14843C105 46,506 -20,746 -30.85 1,059 -22.94 0.0121
2025-08-14 2025-06-30 13F CASTLE BIOSCIENCES COM 14843C105 67,252 14,329 27.08 1,373 29.65 0.0171
2025-05-15 2025-03-31 13F CASTLE BIOSCIENCES COM 14843C105 52,923 34,201 182.68 1,060 112.65 0.0179
2025-02-14 2024-12-31 13F CASTLE BIOSCIENCES COM 14843C105 18,722 -31,360 -62.62 499 -65.13 0.0087
2024-11-14 2024-09-30 13F CASTLE BIOSCIENCES COM 14843C105 50,082 22,710 82.97 1,428 140.00 0.0279
2024-08-14 2024-06-30 13F CASTLE BIOSCIENCES COM 14843C105 27,372 -2,624 -8.75 596 -10.39 0.0134
2024-05-15 2024-03-31 13F CASTLE BIOSCIENCES COM 14843C105 29,996 -1,271 -4.06 664 -1.48 0.0175
2024-02-14 2023-12-31 13F CASTLE BIOSCIENCES COM 14843C105 31,267 31,267 675 0.0193
2023-08-14 2023-06-30 13F CASTLE BIOSCIENCES COM 14843C105 0 -22,560 -100.00 0 -100.00
2023-05-15 2023-03-31 13F CASTLE BIOSCIENCES COM 14843C105 22,560 -16,969 -42.93 513 -44.95 0.0214
2023-02-14 2022-12-31 13F CASTLE BIOSCIENCES COM 14843C105 39,529 29,992 314.48 931 273.49 0.0559
2022-11-14 2022-09-30 13F CASTLE BIOSCIENCES COM 14843C105 9,537 -99,403 -91.25 249 -89.59 0.0155
2022-08-15 2022-06-30 13F CASTLE BIOSCIENCES COM 14843C105 108,940 108,940 2,391 0.0876
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.