Company: CSTL
Filing Date: 2025-11-03
Form Type: 10-Q
Source: 0001628280-25-048254
Chunk: 20

Company: CASTLE BIOSCIENCES INC
Filing Date: 2025-11-03
Form: 10-Q
Item: Item 1
Chunk 20
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 three and nine months ended September 30, 2025 and 2024 because to do so would be antidilutive. With regard to the PSUs, we assume that the associated performance targets will be met at the target level of performance for purposes of calculating diluted earnings per common share until such time that it is probable that actual performance will be above or below target (in thousands): Three Months EndedSeptember 30,Nine Months EndedSeptember 30,2025202420252024Stock options2,893 2,430 2,941 2,466 RSUs and PSUs4,323 474 4,079 553 ESPP153 155 151 207 Total7,369 3,059 7,171 3,226 

5. Marketable Investment Securities 

Marketable investment securities consisted of the following (in thousands):September 30, 2025December 31, 2024Current marketable investment securities:Equity securities$8,907 $3,555 Debt securities - AFS187,495 169,866 Debt securities - HTM(1)5,584 — Total current marketable investment securities$201,986 $173,421 (1)We held no debt securities - HTM as of December 31, 2024.Equity SecuritiesWe recognized unrealized gains of $3.6 million and $3.3 million in our equity securities for the three and nine months ended September 30, 2025, respectively. No gains or losses were recognized for the three and nine months ended September 30, 2024, as we did not hold any equity securities during those periods.

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Table of ContentsCASTLE BIOSCIENCES, INC.NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)(UNAUDITED)

Debt SecuritiesThe following tables present our debt securities (in thousands):September 30, 2025Amortized CostUnrealizedEstimated Fair ValueGainsLossesU.S. government securities - AFS$187,255 $242 $(2)$187,495 U.S. government securities - HTM5,584 9 — 5,593 Total debt securities$192,839 $251 $(2)$193,088 December 31, 2024Amortized CostUnrealizedEstimated Fair ValueGainsLossesU.S. government securities - AFS