Company: CSTL
Filing Date: 2025-11-03
Form Type: 10-Q
Source: 0001628280-25-048254
Chunk: 57

Company: CASTLE BIOSCIENCES INC
Filing Date: 2025-11-03
Form: 10-Q
Item: Item 1
Chunk 57
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 710 as of September 30, 2024. As of September 30, 2025, the total unrecognized stock-based compensation cost related to outstanding awards was $69.6 million, which is expected to be recognized over a weighted-average period of 2.3 years.

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Liquidity and Capital Resources

Sources of Liquidity

Our principal sources of liquidity are our cash and cash equivalents, marketable investment securities and cash generated from the sale of our products. All of our marketable investment securities are considered investment grade and are readily available for use in current operations. As of September 30, 2025 and December 31, 2024, we had marketable investment securities of $202.0 million and $173.4 million, respectively. Additionally, as of September 30, 2025 and December 31, 2024, we had cash and cash equivalents of $85.6 million and $119.7 million, respectively. 

On April 4, 2025, we amended the 2024 Loan and Security Agreement (the “2024 LSA”) to modify certain terms, including the extension of the draw period for our line of credit from March 31, 2025 to September 30, 2025. In August 2025, we exercised the interest-only milestone provision under the 2024 LSA to extend the interest-only period on the term loan from November 30, 2025 to December 1, 2026. As of September 30, 2025, we had not made any draws on the line of credit. The line of credit under the 2024 LSA expired on September 30, 2025 and was no longer available as a source of liquidity thereafter.

Our liquidity has been primarily derived from the revenue generated from the sale of our products. We believe that our existing cash and cash equivalents, marketable investment securities and anticipated cash generated from sales of our products will be sufficient to fund our operations for at least the next 12 months. However, we have based these estimates on assumptions that may prove to be wrong, and could result in us depleting our capital resources sooner than expected.

As mentioned above, we expect to use a portion of our cash and cash equivalents and marketable investment securities to further support and accelerate our R&D activities, including the clinical studies noted above in “—Components of the Results of Operations—Research and Development.”

Material Cash Requirements

Our primary uses of capital are