Company: CSTL
Filing Date: 2025-11-03
Form Type: 10-Q
Source: 0001628280-25-048254
Chunk: 19

Company: CASTLE BIOSCIENCES INC
Filing Date: 2025-11-03
Form: 10-Q
Item: Item 1
Chunk 19
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loss) income for the period by the weighted-average number of common shares outstanding during the period. Diluted (loss) earnings 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) earnings 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) earnings per share when their effect is antidilutive.The following table shows the computation of basic and diluted (loss) earnings per share (in thousands, except per share data): Three Months EndedSeptember 30,Nine Months EndedSeptember 30, 2025202420252024Numerator:Net (loss) income$(501)$2,269 $(21,826)$8,655 Denominator:Weighted-average common shares outstanding, basic29,073 27,840 28,868 27,659 Assumed exercise of stock options— 457 — 447 Assumed vesting of RSUs— 1,041 — 663 Assumed vesting of PSUs— 42 — 55 Assumed issuance of shares under the ESPP— 21 — 14 Weighted-average common shares outstanding, diluted29,073 29,401 28,868 28,838 Earnings (loss) per share:Basic$(0.02)$0.08 $(0.76)$0.31 Diluted$(0.02)$0.08 $(0.76)$0.30 

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

Due to the Company reporting a net loss attributable to common stockholders for the three and nine months ended September 30, 2025, all potentially dilutive securities are antidilutive and are excluded from the computations of diluted loss per share.The table below provides the weighted-average number of potential common shares associated with outstanding securities not included in our calculation of diluted (loss) earnings per share for the