Company: CSTL
Filing Date: 2025-05-05
Form Type: 10-Q
Source: 0001447362-25-000069
Chunk: 14

Company: CASTLE BIOSCIENCES INC
Filing Date: 2025-05-05
Form: 10-Q
Item: Item 1
Chunk 14
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%19 %15 %15 %Payor B**22 %20 %11 %12 %*    Less than 10%There were no other third-party payors that individually accounted for more than 10% of our total revenue or accounts receivable for the periods shown in the table above.

4. Loss Per Share

Basic loss per share is computed by dividing net loss for the period by the weighted-average number of common shares outstanding during the period. Diluted loss per share reflects the additional dilution from potential issuances of common stock, such as stock issuable pursuant to the exercise of stock options, vesting of RSUs and PSUs or purchases under the ESPP. The treasury stock method is used to calculate the potential dilutive effect of these common stock equivalents. Contingently issuable PSU awards are included in the computation of diluted loss per share when the applicable performance criteria would be met and the common shares would be issuable if the end of the reporting period were the end of the contingency period. However, potentially dilutive shares are excluded from the computation of diluted loss per share when their effect is antidilutive.Because we reported a net loss for all periods presented, all potentially dilutive securities are antidilutive and are excluded from the computation of diluted loss per share for such periods.The table below provides the weighted-average number of potential common shares associated with outstanding securities not included in our calculation of diluted loss per share for the three months ended March 31, 2025 and 2024 because to do so would be antidilutive or, in the case of PSUs, the applicable performance conditions have not yet been met (in thousands):Three Months EndedMarch 31,20252024Stock options2,983 3,192 RSUs and PSUs3,739 3,131 ESPP176 333 Total6,898 6,656 

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

5. Marketable Investment Securities 

Marketable investment securities consisted of the following (in thousands):March 31, 2025December 31, 2024Current marketable investment securities:Trading securities$2,130 $3,555 Debt securities - AFS183,332 169,866 Total current marketable investment securities$185,462 $173,421 Long-term marketable