Company: CSTL
Filing Date: 2025-08-04
Form Type: 10-Q
Source: 0001447362-25-000097
Chunk: 115

Company: CASTLE BIOSCIENCES INC
Filing Date: 2025-08-04
Form: 10-Q
Item: Item 8
Chunk 115
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 the three and six months ended June 30, 2024, as we did not hold any trading securities during those periods.Debt securitiesThe following tables present our debt securities (in thousands):June 30, 2025Amortized CostUnrealizedEstimated Fair ValueGainsLossesU.S. government securities - AFS$184,766 $58 $(19)$184,805 U.S. government securities - HTM5,577 2 — 5,579 Total debt securities$190,343 $60 $(19)$190,384 December 31, 2024Amortized CostUnrealizedEstimated Fair ValueGainsLossesU.S. government securities - AFS$169,636 $244 $(14)$169,866 U.S. government securities - HTM(1)— — — — Total debt securities$169,636 $244 $(14)$169,866 (1)  We held no debt securities - HTM as of December 31, 2024.Our U.S. government securities includes both AFS and HTM securities. The AFS securities are available to be sold to meet operating needs or otherwise, but are generally held through maturity. We classify all AFS investments as current assets, as these are readily available for use in current operations. We classify our HTM investments as current assets, as we have the positive intent and ability to hold these investments to maturity, and all such maturities are less than one year from the balance sheet date.We evaluated our U.S. government securities under the AFS and HTM impairment model guidance, respectively, and determined our investment portfolio is comprised of low-risk, investment grade securities.As of June 30, 2025, unrealized losses on our AFS and HTM U.S. government securities are not attributed to credit risk. We believe that an allowance for credit losses is unnecessary because the unrealized losses on certain of our marketable investment securities are due to market factors. The allowance for credit losses was zero as of June 30, 2025 and December 31, 2024.

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

There were no realized gains or losses on sales of debt securities for the three and six months ended June 30, 2025 and 2024. No