Summary of Significant Accounting Policies (Policies)	12 Months Ended
Dec. 31, 2025
Accounting Policies [Abstract]
Basis of Presentation	The consolidated financial statements include the accounts of Castle Biosciences, Inc. and our wholly owned subsidiaries and have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”).
Consolidation	All intercompany accounts and transactions have been eliminated in consolidation. In connection with preparing consolidated financial statements for each annual and interim reporting period, the Company is required to evaluate whether there are conditions or events, considered in aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the financial statements are issued. Substantial doubt exists when conditions and events, considered in aggregate, indicate that it is probable that a company will be unable to meet its obligations as they become due within one year after the date that the consolidated financial statements are issued. This evaluation initially does not take into consideration the potential mitigating effect of management’s plans and actions that have not been fully implemented as of the date that the financial statements are issued. When substantial doubt exists, management evaluates whether the mitigating effect of its plans sufficiently alleviates substantial doubt about the Company’s ability to continue as a going concern. The mitigating effect of management’s plans, however, is only considered if both: (1) it is probable that the plans will be effectively implemented within one year after the date that the financial statements are issued; and (2) it is probable that the plans, when implemented, will mitigate the relevant conditions or events that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the financial statements are issued. Generally, to be considered probable of being effectively implemented, the plans must have been approved before the date that the financial statements are issued.
Use of Estimates	The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates include revenue recognition, the valuation of stock-based compensation, assessing future tax exposure and the realizability of deferred tax assets, the useful lives and recoverability of long-lived assets, the goodwill impairment test, the valuation of acquired intangible assets, allowance for credit losses for assets measured at amortized cost, the valuation of contingent consideration, and other contingent liabilities. We base these estimates on historical and anticipated results, trends and various other assumptions that we believe are reasonable under the circumstances, including assumptions as to future events. These estimates form the basis for making judgments about the carrying values of assets and liabilities and recorded revenues and expenses that are not readily apparent from other sources. Actual results could differ from those estimates and assumptions.
Segment Reporting	Operating segments are components of an enterprise engaging in business activities from which it may recognize revenues and incur expenses, where discrete financial information is available, and where its operating results are regularly reviewed by the public entity’s chief operating decision maker (“CODM”) to make decisions about resources to be allocated to the segment and to assess its performance. A CODM may be an individual or a decision-making group. A reportable segment consists of one or more operating segments.
Cash and Cash Equivalents	Cash equivalents consist of short-term, highly liquid investments with original maturities of three months or less. Our cash equivalents consist of money market funds, which are not insured by the Federal Deposit Insurance Corporation (“FDIC”), that are primarily invested in short-term U.S. government obligations.
Concentrations of Credit Risk	Cash deposits at financial institutions may exceed the amount of insurance provided by the FDIC. Management believes that we are not exposed to significant credit risk on our cash deposits due to the financial position of the financial institutions in which deposits are held.
Marketable Investment Securities	Our marketable investment securities are comprised of debt and equity securities. All debt securities are recognized in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 320, Investments-Debt Securities (“ASC 320”). Management determines the appropriate classification of debt securities at the time of purchase and re-evaluates such determination at each balance sheet date. Debt securities that are classified as available-for-sale (“AFS”) are recorded at fair value in accordance with ASC 320. We recognize the unrealized gains and losses related to changes in fair value as a separate component of accumulated other comprehensive (loss) income within total stockholders’ equity, net of any related deferred income tax effects, on the consolidated balance sheets. Debt securities that are classified as held-to-maturity (“HTM”) are reported at amortized cost in accordance with ASC 320. Premiums or discounts from par value are amortized to interest income over the life of the underlying investment and are included in interest income in the consolidated statements of operations. Realized gains and losses on AFS and HTM debt securities, if any, are calculated at the individual security level and are included in interest income in the consolidated statements of operations. Impairments of AFS or HTM debt securities, if any, are recorded in the consolidated statements of operations. Our equity securities consist of investments in shares of common stock which are listed and traded on the Nasdaq Global Market and certain foreign exchanges. All equity securities are recognized in accordance with ASC Topic 321, Investments-Equity Securities (“ASC 321”) and reported at their readily determinable fair values based on quoted market prices where changes in fair value are included in net gains on equity securities in the consolidated statements of operations. For investments denominated in a foreign currency, the fair value is remeasured into U.S. dollars using exchange rates in effect at each balance sheet date in accordance with ASC Topic 830, Foreign Currency Matters (“ASC 830”). As a result, changes in fair value include the effects of both market price movements and foreign currency exchange rate fluctuations. All changes in a marketable security’s fair value are reported in earnings as they occur, and the sale of our equity securities does not necessarily give rise to a significant gain or loss. Investments in equity securities are classified as either current or long-term depending upon management’s intentions. We updated our terminology to refer to these investments as equity securities rather than trading securities to align with the terminology in ASC 321.
Revenue Recognition, Cost of Sales (exclusive of amortization of acquired intangible assets)	In accordance with ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”), we follow a five-step process to recognize revenues: (1) identify the contract with the customer, (2) identify the performance obligations, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations and (5) recognize revenues when the performance obligations are satisfied. We have determined that we have a contract with the patient when the treating clinician orders the test. Our contracts generally contain a single performance obligation, which is the delivery of the test report, and we satisfy our performance obligation at a point in time upon the delivery of the test report to the treating clinician, at which point we can bill for the report. The amount of revenue recognized reflects the amount of consideration to which we expect to be entitled, or the transaction price, and considers the effects of variable consideration. Cost of sales is expensed as incurred and includes material and service costs associated with testing samples, personnel costs (including salaries, bonuses, benefits and stock-based compensation expense), electronic medical records, order and delivery systems, shipping charges to transport samples, third-party test fees, and allocated overhead including rent, information technology costs, equipment and facilities depreciation and utilities.
Collaborative Arrangements	We assess whether our licensing and other agreements are collaborative arrangements based on whether they involve joint operating activities and whether both parties have active participation in the arrangement and are exposed to significant risks and rewards. For arrangements that we determine are collaborations, we identify each unit of account and then determine whether a customer relationship exists for that unit of account. If we determine that a performance obligation within the collaborative arrangement is with a customer, we apply ASC 606. If a portion of a distinct bundle of goods or services within the collaborative arrangement is not with a customer, we apply recognition and measurement based on an analogy to authoritative accounting literature or, if there is no appropriate analogy, a reasonable, rational, and consistently applied accounting policy election. To the extent the arrangement is within the scope of ASC Topic 808, Collaborative Arrangements (“ASC 808”), we assess whether aspects of the arrangement are within the scope of other accounting literature. In June 2025, we entered into a Collaboration and License Agreement with SciBase Holding AB (“SciBase”). Following approval under the Swedish Screening of Foreign Direct Investments Act in the third quarter of 2025, subsequent to approval, we completed our investment in SciBase. The agreement aims to jointly develop diagnostic tests for dermatologic diseases, initially focused on atopic dermatitis, by combining SciBase’s Electrical Impedance Spectroscopy technology with our diagnostic and development expertise. Under the arrangement, we hold development and commercialization rights in North America, while SciBase retains rights in certain other territories. SciBase is entitled to royalties on our product sales, a mark-up on product sales to us, and a milestone payment upon achieving specified sales thresholds. Development costs are shared; however, SciBase deferred its initial clinical development costs for the initial indication and we will recover those costs through future royalty payments reductions. We determined the agreement is a collaborative arrangement under ASC 808. Certain elements of the arrangement, including license rights and sales-based royalty provisions, represent transactions with a customer and are therefore accounted for under ASC 606. Other elements, such as shared development activities and cost reimbursements, are accounted for in accordance with ASC 808 and presented as reductions to research and development (“R&D”) expenses.
Accounts Receivable	We classify accounts receivable balances that are expected to be paid more than one year from the consolidated balance sheet date as noncurrent assets. The estimated timing of payment utilized as a basis for classification as noncurrent is determined by analyses of historical payor-specific payment experience, adjusted for known factors that are expected to change the timing of future payments.
Allowance for Credit Losses	We accrue an allowance for credit losses against our accounts receivable based on management’s current estimate of amounts that will not be collected. Management’s estimates are typically based on historical loss information adjusted for current conditions. We generally do not perform evaluations of customers’ financial condition and generally do not require collateral. Historically, our credit losses have not been significant. The allowance for credit losses was zero as of December 31, 2025 and 2024. Adjustments for implicit price concessions attributable to variable consideration, as discussed below, are incorporated into the measurement of the accounts receivable balances and are not part of the allowance for credit losses.
Financing Receivable	We accounted for the convertible loan as a receivable within the scope of ASC Topic 310, Receivables. The carrying amount of the convertible loan is presented at amortized cost, within long-term other assets in the consolidated balance sheets. The Convertible Loan Agreement is remeasured into U.S. dollars using exchange rates in effect at each balance sheet date in accordance with ASC 830 with changes in exchange rates recognized in earnings. In addition, the embedded conversion feature to shares of SciBase did not meet the definition of a derivative and was not bifurcated from the host contract under ASC Topic 815, Derivatives and Hedging. We have determined that expected credit losses associated with the loan are insignificant and, accordingly, have not recorded a credit loss allowance under ASC Topic 326-20, Financial Instruments - Credit Losses. Interest income on the Convertible Loan Receivable is recognized quarterly and included in interest income in the consolidated statements of operations. Accrued interest receivable is recorded within prepaid expenses and other current assets in the consolidated balance sheets.
Inventory	We carry inventories of test supplies in our laboratory facilities. The inventories are carried at the lower of weighted average cost and net realizable value and expensed through cost of sales as the supplies are used.
Property and Equipment	Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation is computed using the straight-line method over the estimated useful lives of the assets, generally between five and ten years. Leasehold improvements are amortized using the straight-line method over the shorter of the estimated useful life of the asset or the term of the lease. Our leasehold improvements primarily relate to our office and laboratory facilities located in Friendswood, Texas, Phoenix, Arizona and Pittsburgh, Pennsylvania, and are generally depreciated over the remaining lease terms, which end in 2026, 2034 and 2033, respectively. Maintenance and repairs are charged to expense as incurred, and material improvements are capitalized. Interest costs incurred during the construction of major capital projects are capitalized until the underlying asset is ready for its intended use, at which point the capitalized interest costs are amortized using the straight-line method over the estimated useful life of the underlying asset. When assets are retired or otherwise disposed of, the cost and accumulated depreciation are removed from the consolidated balance sheet and any resulting gain or loss is reflected in the consolidated statements of operations in the period realized.
Intangible Assets	Our intangible assets, which are comprised primarily of acquired developed technology, are considered to be finite-lived and are amortized on a straight-line basis over their estimated useful lives.
Goodwill	Goodwill represents the excess of the purchase price over the fair value of the net tangible and intangible assets acquired in a business combination. Goodwill is not amortized, but is tested for impairment. We test goodwill for impairment in the fourth quarter of each fiscal year and when events, or changes in circumstances, indicate that it may be impaired. Events and changes in circumstances indicating that goodwill may be impaired include sustained declines in the price of our common stock, increased competition, changes in macroeconomic developments, unfavorable government or regulatory developments and changes in coverage or reimbursement conditions. Goodwill is tested for impairment at the reporting unit level where goodwill is held. Testing begins with completion of an optional qualitative assessment. If the qualitative assessment suggests that impairment is more likely than not, quantitative testing is conducted. If the qualitative assessment is bypassed, we proceed directly to quantitative testing. Quantitative testing consists of comparing the carrying value of goodwill to its estimated fair value. Impairment of goodwill is the condition that exists when the carrying value exceeds its fair value. Amounts by which carrying value exceed fair value, up to the total amount of goodwill allocated to the reporting unit, are recognized as an impairment loss in the consolidated statements of operations.
Long-Lived Assets	We review long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. An impairment loss is recognized when the total of estimated future undiscounted cash flows, expected to result from the use of the asset and its eventual disposition, are less than the carrying amount. Impairment, if any, would be calculated based on the excess of the carrying amount of the long-lived asset over the long-lived asset’s fair value.
Acquisitions, Contingent Consideration	We assess acquisitions under ASC Topic 805, Business Combinations (“ASC 805”), to determine whether a transaction represents the acquisition of assets or a business combination. Under this guidance, we apply a two-step model. The first step involves a screening test where we evaluate whether substantially all of the fair value of the gross assets acquired is concentrated in a single asset or a group of similar assets. If the screening test is met, we account for the set as an asset acquisition. If the screening test is not met, we apply the second step of the model to determine if the set meets the definition of a business based on the guidance in ASC 805. If so, the transaction is treated as a business combination. Otherwise, it is treated as an asset acquisition. Asset acquisitions are accounted for by allocating the cost of the acquisition, including transaction costs, to the individual assets acquired and liabilities assumed on a relative fair value basis without recognition of goodwill. If the total consideration transferred is less than the aggregate fair value of the net assets acquired (i.e., a bargain purchase), the difference is not recognized as a gain. Instead, the difference is allocated to the cost of the acquired assets on a relative fair value basis. Business combinations are accounted for using the acquisition method. Under the acquisition method, goodwill is measured as a residual amount equal to the fair value of the consideration transferred less the net recognized fair value of the identifiable assets acquired and the liabilities assumed, as of the acquisition date, and transaction costs are expensed as incurred. Under the terms of business combinations or asset acquisitions, we may be required to pay additional consideration if specified future events occur or if certain conditions are met. In May 2025, we acquired Capsulomics, Inc., d/b/a Previse (“Previse”), which was recorded as an asset acquisition, and agreed to pay additional consideration of up to $2.5 million in cash based on the achievement of certain commercial milestones (the “Earnout Payments”). We account for the contingent consideration as a liability in accordance with ASC Topic 450-20, Loss Contingencies (“ASC 450-20”) when it is both probable and reasonably estimable. In accordance with ASC 450-20, we recorded the contingent consideration at the amount required to settle the respective obligation, and subsequent changes are recognized as adjustments to the cost basis of the acquired assets. These changes are allocated to the acquired assets based on their relative fair values as of the date of acquisition. In December of 2025, one of the commercial milestones was achieved. As a result, an Earnout Payment of $0.5 million became payable and will be paid within 60 days of milestone achievement. Contingent consideration is classified as current or noncurrent in the consolidated balance sheets based on the contractual timing of future settlement.
Leases	We account for leases in accordance with ASC Topic 842, Leases (“ASC 842”). We categorize leases at their commencement as either operating or finance leases based on the criteria in ASC 842. Under ASC 842, we record right-of-use (“ROU”) assets and lease liabilities for each lease arrangement identified, except that we have elected the short-term lease exemption for all leases with a term of 12 months or less. Lease liabilities are recorded at the present value of future lease payments discounted using our incremental borrowing rate for the lease established at the commencement date and ROU assets are measured at the amount of the lease liability plus any initial direct costs, less any lease incentives received before commencement. For our operating leases, we recognize a single lease cost over the lease term on a straight-line basis. We have elected the practical expedient of not separating nonlease components from lease components in all leases.
Research and Development	R&D costs are charged to operations as incurred. Advance payments for goods and services that will be used in future R&D activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made. Upfront and milestone payments due to third parties that perform R&D services on behalf of us will be expensed as services are rendered or when the milestone is achieved. R&D costs include, but are not limited to, payroll and personnel-related expenses, stock-based compensation expense, materials, laboratory supplies and consulting costs.
Selling, General and Administrative Expenses	Selling, general and administrative (“SG&A”) expenses are attributable to sales, marketing, executive, finance and accounting, legal and human resources functions. These expenses consist of personnel costs (including salaries, employee benefit costs, bonuses and stock-based compensation expenses), customer services expenses, direct marketing expenses, educational and promotional expenses, market research, audit and legal expenses and consulting. We expense all SG&A costs as incurred.
Accrued Compensation	We accrue for liabilities under discretionary employee and executive bonus plans. Our estimated compensation liabilities are based on progress against corporate objectives approved by our board of directors, compensation levels of eligible individuals and target bonus percentage levels. Our board of directors reviews and evaluates the performance against these objectives and ultimately determines the actual achievement levels attained. We also accrue for liabilities under employee sales incentive bonus plans with accruals based on performance achieved to date compared to established targets. As of December 31, 2025 and 2024, we accrued approximately $28.1 million and $23.3 million, respectively, for liabilities associated with these bonus plans. These amounts are classified as current or noncurrent accrued liabilities based on the expected timing of payment.
Retirement Plan	We have an Internal Revenue Code (“IRC”) Section 401(k) profit sharing plan (the “Plan”) for eligible employees. The Plan is funded by employee contributions and provides for discretionary contributions in the form of matching and/or profit-sharing contributions.
Income Taxes	We use the asset and liability method of accounting for income taxes. Current income taxes are recognized for the estimated taxes payable or refundable on tax returns for the current year. Deferred income taxes arise from the recognition of temporary differences between financial statement carrying amounts and the tax basis of assets and liabilities. We consider all evidence, both positive and negative, with respect to our net operating loss (“NOL”) carryforwards, expected levels of pre-tax financial statement income (loss), taxable income (benefit), liquidity, and prudent and reasonable tax planning strategies when evaluating whether the temporary differences will be realized. In projecting future taxable income (loss), we begin with budgeted pre-tax income (loss) adjusted for estimated taxable and non-taxable items. The assumptions about future taxable income (loss) require significant judgment and are consistent with the plans and estimates we use to manage our businesses. A valuation allowance is established when it is more likely than not that some portion of the deferred tax asset will not be realized. The evaluation of a valuation allowance considers the character of the taxable income, ordinary income versus capital income. Tax benefits are recognized only for tax positions that are more likely than not to be sustained upon examination by tax authorities. The amount recognized is measured as the largest amount of benefit that is greater than 50% likely to be realized upon settlement. A liability for unrecognized tax benefits is recorded for any tax benefits claimed in our tax returns that do not meet these recognition and measurement standards. The effect of a change in tax rates is recognized in the period of enactment. If we were to be levied interest and penalties by the Internal Revenue Service, these amounts would be recognized as a component of income tax expense in the consolidated statements of operations. Our policy for recording interest and penalties associated with uncertain tax positions is to record such items as a component of tax expense.
Stock-Based Compensation	Stock-based compensation expense for equity instruments is measured based on the grant-date fair value of the awards. For stock option awards and purchase rights made under the 2019 Employee Stock Purchase Plan (the “ESPP”), the fair value is estimated on the date of grant using the Black-Scholes option-pricing valuation model. For restricted stock units (“RSUs”) and performance-based restricted stock units (“PSUs”), the fair value is equal to the closing price of our common stock on the date of grant. For awards with graded vesting and only service conditions, we recognize compensation costs on a straight-line basis over the requisite service period of the awards. For stock options and RSUs, the requisite service period is generally the award’s vesting period (typically four years). PSUs vest upon the achievement of certain performance conditions and the provision of service with us through a specified period. Accruals of compensation cost for PSUs are based on the probable outcome of the performance conditions and are reassessed each reporting period. We recognize compensation cost for PSUs separately for each vesting tranche on a ratable basis over the requisite service period. The requisite service period for PSUs is based on an analysis of vesting requirements and performance conditions for the particular award. Certain employees are entitled to acceleration of vesting of a portion of their awards upon retirement, subject to age, service and notice requirements (“Retirement Policy”). Stock-based awards falling into the scope of the Retirement Policy are accounted for as a modification of existing awards under ASC Topic 718, Compensation – Stock Compensation. The modifications do not result in the recognition of incremental compensation cost, however, they do result in a new estimate of the requisite service period, which we reassess at each balance sheet date. For the ESPP, the requisite service period is generally the period of time from the offering date to the purchase date. Forfeitures are accounted for as they occur.
Comprehensive (Loss) Income	Comprehensive (loss) income is defined as a change in equity during a period from transactions and other events and circumstances from non-owner sources. Comprehensive (loss) income is made up of net (loss) income plus net unrealized gain (loss) on marketable investment securities, which is our only other item of other comprehensive (loss) income.
Recently Adopted Accounting Pronouncements and Accounting Pronouncements Yet to be Adopted	In December 2023, the FASB issued Accounting Standards Update (“ASU”) No. 2023-09, Income Taxes (Topic 740)—Improvements to Income Tax Disclosures (“ASU 2023-09”), which is intended to enhance the transparency and decision usefulness of income tax disclosures. The amendments in ASU 2023-09 provide for enhanced income tax information primarily through changes to the rate reconciliation and income taxes paid information. The guidance was effective for public entities for fiscal years beginning after December 15, 2024. We adopted ASU 2023-09 prospectively in fiscal year 2025 for the annual reporting period ending December 31, 2025. For additional information on our tax disclosure, see Note 15. Accounting Pronouncements Yet to be Adopted In November 2024, the FASB issued ASU No. 2024-03, Income Statement—Reporting Comprehensive Income (Subtopic 220-40)—Expense Disaggregation Disclosures: Disaggregation of Income Statement Expenses (“ASU 2024-03”), which specifies additional disclosure requirements. The amendments in ASU 2024-03 require disclosure about the composition of certain income expense line items, such as purchases of inventory, employee compensation, and other expenses, as well as disclosure about selling expenses. The ASU is effective for fiscal years beginning after December 15, 2026, and interim periods beginning after December 15, 2027. Early adoption is permitted. We are currently evaluating the impact this update will have on the consolidated financial statements and disclosures. In July 2025, the FASB issued ASU No. 2025-05, Financial Instruments—Credit Losses (Topic 326): Practical Expedient for Certain Current Receivables (“ASU 2025-05”), which provides a practical expedient for estimating expected credit losses on current accounts receivable and contract assets arising from transactions under ASC 606. The practical expedient allows entities to assume that current conditions remain unchanged over the remaining life of the receivables. ASU 2025-05 is effective for annual periods beginning after December 15, 2025, including interim periods within those annual periods. Early adoption is permitted. We are currently evaluating the impact this update will have on the consolidated financial statements and disclosures. We have evaluated all other recently issued, but not yet effective, accounting pronouncements and do not believe that these accounting pronouncements will have any material impact on the consolidated financial statements or disclosures upon adoption.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2025

The consolidated financial statements include the accounts of Castle Biosciences, Inc. and our wholly owned subsidiaries and have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”).

Consolidation

All intercompany accounts and transactions have been eliminated in consolidation.

In connection with preparing consolidated financial statements for each annual and interim reporting period, the Company is required to evaluate whether there are conditions or events, considered in aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the financial statements are issued. Substantial doubt exists when conditions and events, considered in aggregate, indicate that it is probable that a company will be unable to meet its obligations as they become due within one year after the date that the consolidated financial statements are issued. This evaluation initially does not take into consideration the potential mitigating effect of management’s plans and actions that have not been fully implemented as of the date that the financial statements are issued. When substantial doubt exists, management evaluates whether the mitigating effect of its plans sufficiently alleviates substantial doubt about the Company’s ability to continue as a going concern. The mitigating effect of management’s plans, however, is only considered if both: (1) it is probable that the plans will be effectively implemented within one year after the date that the financial statements are issued; and (2) it is probable that the plans, when implemented, will mitigate the relevant conditions or events that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the financial statements are issued. Generally, to be considered probable of being effectively implemented, the plans must have been approved before the date that the financial statements are issued.

Use of Estimates

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates include revenue recognition, the valuation of stock-based compensation, assessing future tax exposure and the realizability of deferred tax assets, the useful lives and recoverability of long-lived assets, the goodwill impairment test, the valuation of acquired intangible assets, allowance for credit losses for assets measured at amortized cost, the valuation of contingent consideration, and other contingent liabilities. We base these estimates on historical and anticipated results, trends and various other assumptions that we believe are reasonable under the circumstances, including assumptions as to future events. These estimates form the basis for making judgments about the carrying values of assets and liabilities and recorded revenues and expenses that are not readily apparent from other sources. Actual results could differ from those estimates and assumptions.

Segment Reporting

Operating segments are components of an enterprise engaging in business activities from which it may recognize revenues and incur expenses, where discrete financial information is available, and where its operating results are regularly reviewed by the public entity’s chief operating decision maker (“CODM”) to make decisions about resources to be allocated to the segment and to assess its performance. A CODM may be an individual or a decision-making group. A reportable segment consists of one or more operating segments.

Cash and Cash Equivalents

Cash equivalents consist of short-term, highly liquid investments with original maturities of three months or less. Our cash equivalents consist of money market funds, which are not insured by the Federal Deposit Insurance Corporation (“FDIC”), that are primarily invested in short-term U.S. government obligations.

Concentrations of Credit Risk

Cash deposits at financial institutions may exceed the amount of insurance provided by the FDIC. Management believes that we are not exposed to significant credit risk on our cash deposits due to the financial position of the financial institutions in which deposits are held.

Marketable Investment Securities

Our marketable investment securities are comprised of debt and equity securities. All debt securities are recognized in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 320, Investments-Debt Securities (“ASC 320”).

Management determines the appropriate classification of debt securities at the time of purchase and re-evaluates such determination at each balance sheet date. Debt securities that are classified as available-for-sale (“AFS”) are recorded at fair value in accordance with ASC 320. We recognize the unrealized gains and losses related to changes in fair value as a separate component of accumulated other comprehensive (loss) income within total stockholders’ equity, net of any related deferred income tax effects, on the consolidated balance sheets. Debt securities that are classified as held-to-maturity (“HTM”) are reported at amortized cost in accordance with ASC 320. Premiums or discounts from par value are amortized to interest income over the life of the underlying investment and are included in interest income in the consolidated statements of operations. Realized gains and losses on AFS and HTM debt securities, if any, are calculated at the individual security level and are included in interest income in the consolidated statements of operations. Impairments of AFS or HTM debt securities, if any, are recorded in the consolidated statements of operations.

Our equity securities consist of investments in shares of common stock which are listed and traded on the Nasdaq Global Market and certain foreign exchanges. All equity securities are recognized in accordance with ASC Topic 321, Investments-Equity Securities (“ASC 321”) and reported at their readily determinable fair values based on quoted market prices where changes in fair value are included in net gains on equity securities in the consolidated statements of operations. For investments denominated in a foreign currency, the fair value is remeasured into U.S. dollars using exchange rates in effect at each balance sheet date in accordance with ASC Topic 830, Foreign Currency Matters (“ASC 830”). As a result, changes in fair value include the effects of both market price movements and foreign currency exchange rate fluctuations. All changes in a marketable security’s fair value are reported in earnings as they occur, and the sale of our equity securities does not necessarily give rise to a significant gain or loss. Investments in equity securities are classified as either current or long-term depending upon management’s intentions. We updated our terminology to refer to these investments as equity securities rather than trading securities to align with the terminology in ASC 321.

Revenue Recognition, Cost of Sales (exclusive of amortization of acquired intangible assets)

In accordance with ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”), we follow a five-step process to recognize revenues: (1) identify the contract with the customer, (2) identify the performance obligations, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations and (5) recognize revenues when the performance obligations are satisfied. We have determined that we have a contract with the patient when the treating clinician orders the test. Our contracts generally contain a single performance obligation, which is the delivery of the test report, and we satisfy our performance obligation at a point in time upon the delivery of the test report to the treating clinician, at which point we can bill for the report. The amount of revenue recognized reflects the amount of consideration to which we expect to be entitled, or the transaction price, and considers the effects of variable consideration.

Cost of sales is expensed as incurred and includes material and service costs associated with testing samples, personnel costs (including salaries, bonuses, benefits and stock-based compensation expense), electronic medical records, order and delivery systems, shipping charges to transport samples, third-party test fees, and allocated overhead including rent, information technology costs, equipment and facilities depreciation and utilities.

Collaborative Arrangements

We assess whether our licensing and other agreements are collaborative arrangements based on whether they involve joint operating activities and whether both parties have active participation in the arrangement and are exposed to significant risks and rewards. For arrangements that we determine are collaborations, we identify each unit of account and then determine whether a customer relationship exists for that unit of account. If we determine that a performance obligation within the collaborative arrangement is with a customer, we apply ASC 606.

If a portion of a distinct bundle of goods or services within the collaborative arrangement is not with a customer, we apply recognition and measurement based on an analogy to authoritative accounting literature or, if there is no appropriate analogy, a reasonable, rational, and consistently applied accounting policy election. To the extent the arrangement is within the scope of ASC Topic 808, Collaborative Arrangements (“ASC 808”), we assess whether aspects of the arrangement are within the scope of other accounting literature.

In June 2025, we entered into a Collaboration and License Agreement with SciBase Holding AB (“SciBase”). Following approval under the Swedish Screening of Foreign Direct Investments Act in the third quarter of 2025, subsequent to approval, we completed our investment in SciBase. The agreement aims to jointly develop diagnostic tests for dermatologic diseases, initially focused on atopic dermatitis, by combining SciBase’s Electrical Impedance Spectroscopy technology with our diagnostic and development expertise. Under the arrangement, we hold development and commercialization rights in North America, while SciBase retains rights in certain other territories. SciBase is entitled to royalties on our product sales, a mark-up on product sales to us, and a milestone payment upon achieving specified sales thresholds. Development costs are shared; however, SciBase deferred its initial clinical development costs for the initial indication and we will recover those costs through future royalty payments reductions.

We determined the agreement is a collaborative arrangement under ASC 808. Certain elements of the arrangement, including license rights and sales-based royalty provisions, represent transactions with a customer and are therefore accounted for under ASC 606. Other elements, such as shared development activities and cost reimbursements, are accounted for in accordance with ASC 808 and presented as reductions to research and development (“R&D”) expenses.

Accounts Receivable

We classify accounts receivable balances that are expected to be paid more than one year from the consolidated balance sheet date as noncurrent assets. The estimated timing of payment utilized as a basis for classification as noncurrent is determined by analyses of historical payor-specific payment experience, adjusted for known factors that are expected to change the timing of future payments.

Allowance for Credit Losses

We accrue an allowance for credit losses against our accounts receivable based on management’s current estimate of amounts that will not be collected. Management’s estimates are typically based on historical loss information adjusted for current conditions. We generally do not perform evaluations of customers’ financial condition and generally do not require collateral. Historically, our credit losses have not been significant. The allowance for credit losses was zero as of December 31, 2025 and 2024. Adjustments for implicit price concessions attributable to variable consideration, as discussed below, are incorporated into the measurement of the accounts receivable balances and are not part of the allowance for credit losses.

Financing Receivable

We accounted for the convertible loan as a receivable within the scope of ASC Topic 310, Receivables. The carrying amount of the convertible loan is presented at amortized cost, within long-term other assets in the consolidated balance sheets. The Convertible Loan Agreement is remeasured into U.S. dollars using exchange rates in effect at each balance sheet date in accordance with ASC 830 with changes in exchange rates recognized in earnings. In addition, the embedded conversion feature to shares of SciBase did not meet the definition of a derivative and was not bifurcated from the host contract under ASC Topic 815, Derivatives and Hedging. We have determined that expected credit losses associated with the loan are insignificant and, accordingly, have not recorded a credit loss allowance under ASC Topic 326-20, Financial Instruments - Credit Losses.

Interest income on the Convertible Loan Receivable is recognized quarterly and included in interest income in the consolidated statements of operations. Accrued interest receivable is recorded within prepaid expenses and other current assets in the consolidated balance sheets.

Inventory

We carry inventories of test supplies in our laboratory facilities. The inventories are carried at the lower of weighted average cost and net realizable value and expensed through cost of sales as the supplies are used.

Property and Equipment

Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation is computed using the straight-line method over the estimated useful lives of the assets, generally between five and ten years. Leasehold improvements are amortized using the straight-line method over the shorter of the estimated useful life of the asset or the term of the lease. Our leasehold improvements primarily relate to our office and laboratory facilities located in Friendswood, Texas, Phoenix, Arizona and Pittsburgh, Pennsylvania, and are generally depreciated over the remaining lease terms, which end in 2026, 2034 and 2033, respectively. Maintenance and repairs are charged to expense as incurred, and material improvements are capitalized. Interest costs incurred during the construction of major capital projects are capitalized until the underlying asset is ready for its intended use, at which point the capitalized interest costs are amortized using the straight-line method over the estimated useful life of the underlying asset. When assets are retired or otherwise disposed of, the cost and accumulated depreciation are removed from the consolidated balance sheet and any resulting gain or loss is reflected in the consolidated statements of operations in the period realized.

Intangible Assets

Our intangible assets, which are comprised primarily of acquired developed technology, are considered to be finite-lived and are amortized on a straight-line basis over their estimated useful lives.

Goodwill

Goodwill represents the excess of the purchase price over the fair value of the net tangible and intangible assets acquired in a business combination. Goodwill is not amortized, but is tested for impairment. We test goodwill for impairment in the fourth quarter of each fiscal year and when events, or changes in circumstances, indicate that it may be impaired. Events and changes in circumstances indicating that goodwill may be impaired include sustained declines in the price of our common stock, increased competition, changes in macroeconomic developments, unfavorable government or regulatory developments and changes in coverage or reimbursement conditions.

Goodwill is tested for impairment at the reporting unit level where goodwill is held. Testing begins with completion of an optional qualitative assessment. If the qualitative assessment suggests that impairment is more likely than not, quantitative testing is conducted. If the qualitative assessment is bypassed, we proceed directly to quantitative testing. Quantitative testing consists of comparing the carrying value of goodwill to its estimated fair value. Impairment of goodwill is the condition that exists when the carrying value exceeds its fair value. Amounts by which carrying value exceed fair value, up to the total amount of goodwill allocated to the reporting unit, are recognized as an impairment loss in the consolidated statements of operations.

Long-Lived Assets

We review long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. An impairment loss is recognized when the total of estimated future undiscounted cash flows, expected to result from the use of the asset and its eventual disposition, are less than the carrying amount. Impairment, if any, would be calculated based on the excess of the carrying amount of the long-lived asset over the long-lived asset’s fair value.

Acquisitions, Contingent Consideration

We assess acquisitions under ASC Topic 805, Business Combinations (“ASC 805”), to determine whether a transaction represents the acquisition of assets or a business combination. Under this guidance, we apply a two-step model. The first step involves a screening test where we evaluate whether substantially all of the fair value of the gross assets acquired is concentrated in a single asset or a group of similar assets. If the screening test is met, we account for the set as an asset acquisition. If the screening test is not met, we apply the second step of the model to determine if the set meets the definition of a business based on the guidance in ASC 805. If so, the transaction is treated as a business combination. Otherwise, it is treated as an asset acquisition. Asset acquisitions are accounted for by allocating the cost of the acquisition, including transaction costs, to the individual assets acquired and liabilities assumed on a relative fair value basis without recognition of goodwill. If the total consideration transferred is less than the aggregate fair value of the net assets acquired (i.e., a bargain purchase), the difference is not recognized as a gain. Instead, the difference is allocated to the cost of the acquired assets on a relative fair value basis. Business combinations are accounted for using the acquisition method. Under the acquisition method, goodwill is measured as a residual amount equal to the fair value of the consideration transferred less the net recognized fair value of the identifiable assets acquired and the liabilities assumed, as of the acquisition date, and transaction costs are expensed as incurred.

Under the terms of business combinations or asset acquisitions, we may be required to pay additional consideration if specified future events occur or if certain conditions are met. In May 2025, we acquired Capsulomics, Inc., d/b/a Previse (“Previse”), which was recorded as an asset acquisition, and agreed to pay additional consideration of up to $2.5 million in cash based on the achievement of certain commercial milestones (the “Earnout Payments”). We account for the contingent consideration as a liability in accordance with ASC Topic 450-20, Loss Contingencies (“ASC 450-20”) when it is both probable and reasonably estimable. In accordance with ASC 450-20, we recorded the contingent consideration at the amount required to settle the respective obligation, and subsequent changes are recognized as adjustments to the cost basis of the acquired assets. These changes are allocated to the acquired assets based on their relative fair values as of the date of acquisition. In December of 2025, one of the commercial milestones was achieved. As a result, an Earnout Payment of $0.5 million became payable and will be paid within 60 days of milestone achievement.

Contingent consideration is classified as current or noncurrent in the consolidated balance sheets based on the contractual timing of future settlement.

Leases

We account for leases in accordance with ASC Topic 842, Leases (“ASC 842”). We categorize leases at their commencement as either operating or finance leases based on the criteria in ASC 842. Under ASC 842, we record right-of-use (“ROU”) assets and lease liabilities for each lease arrangement identified, except that we have elected the short-term lease exemption for all leases with a term of 12 months or less. Lease liabilities are recorded at the present value of future lease payments discounted using our incremental borrowing rate for the lease established at the commencement date and ROU assets are measured at the amount of the lease liability plus any initial direct costs, less any lease incentives received before commencement. For our operating leases, we recognize a single lease cost over the lease term on a straight-line basis. We have elected the practical expedient of not separating nonlease components from lease components in all leases.

Research and Development

R&D costs are charged to operations as incurred. Advance payments for goods and services that will be used in future R&D activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made. Upfront and milestone payments due to third parties that perform R&D services on behalf of us will be expensed as services are rendered or when the milestone is achieved.

R&D costs include, but are not limited to, payroll and personnel-related expenses, stock-based compensation expense, materials, laboratory supplies and consulting costs.

Selling, General and Administrative Expenses

Selling, general and administrative (“SG&A”) expenses are attributable to sales, marketing, executive, finance and accounting, legal and human resources functions. These expenses consist of personnel costs (including salaries, employee benefit costs, bonuses and stock-based compensation expenses), customer services expenses, direct marketing expenses, educational and promotional expenses, market research, audit and legal expenses and consulting. We expense all SG&A costs as incurred.

Accrued Compensation

We accrue for liabilities under discretionary employee and executive bonus plans. Our estimated compensation liabilities are based on progress against corporate objectives approved by our board of directors, compensation levels of eligible individuals and target bonus percentage levels. Our board of directors reviews and evaluates the performance against these objectives and ultimately determines the actual achievement levels attained. We also accrue for liabilities under employee sales incentive bonus plans with accruals based on performance achieved to date compared to established targets. As of December 31, 2025 and 2024, we accrued approximately $28.1 million and $23.3 million, respectively, for liabilities associated with these bonus plans. These amounts are classified as current or noncurrent accrued liabilities based on the expected timing of payment.

Retirement Plan

We have an Internal Revenue Code (“IRC”) Section 401(k) profit sharing plan (the “Plan”) for eligible employees. The Plan is funded by employee contributions and provides for discretionary contributions in the form of matching and/or profit-sharing contributions.

Income Taxes

We use the asset and liability method of accounting for income taxes. Current income taxes are recognized for the estimated taxes payable or refundable on tax returns for the current year. Deferred income taxes arise from the recognition of temporary differences between financial statement carrying amounts and the tax basis of assets and liabilities. We consider all evidence, both positive and negative, with respect to our net operating loss (“NOL”) carryforwards, expected levels of pre-tax financial statement income (loss), taxable income (benefit), liquidity, and prudent and reasonable tax planning strategies when evaluating whether the temporary differences will be realized. In projecting future taxable income (loss), we begin with budgeted pre-tax income (loss) adjusted for estimated taxable and non-taxable items. The assumptions about future taxable income (loss) require significant judgment and are consistent with the plans and estimates we use to manage our businesses. A valuation allowance is established when it is more likely than not that some portion of the deferred tax asset will not be realized. The evaluation of a valuation allowance considers the character of the taxable income, ordinary income versus capital income. Tax benefits are recognized only for tax positions that are more likely than not to be sustained upon examination by tax authorities. The amount recognized is measured as the largest amount of benefit that is greater than 50% likely to be realized upon settlement. A liability for unrecognized tax benefits is recorded for any tax benefits claimed in our tax returns that do not meet these recognition and measurement standards. The effect of a change in tax rates is recognized in the period of enactment. If we were to be levied interest and penalties by the Internal Revenue Service, these amounts would be recognized as a component of income tax expense in the consolidated statements of operations.

Our policy for recording interest and penalties associated with uncertain tax positions is to record such items as a component of tax expense.

Stock-Based Compensation

Stock-based compensation expense for equity instruments is measured based on the grant-date fair value of the awards. For stock option awards and purchase rights made under the 2019 Employee Stock Purchase Plan (the “ESPP”), the fair value is estimated on the date of grant using the Black-Scholes option-pricing valuation model. For restricted stock units (“RSUs”) and performance-based restricted stock units (“PSUs”), the fair value is equal to the closing price of our common stock on the date of grant. For awards with graded vesting and only service conditions, we recognize compensation costs on a straight-line basis over the requisite service period of the awards. For stock options and RSUs, the requisite service period is generally the award’s vesting period (typically four years). PSUs vest upon the achievement of certain performance conditions and the provision of service with us through a specified period. Accruals of compensation cost for PSUs are based on the probable outcome of the performance conditions and are reassessed each reporting period. We recognize compensation cost for PSUs separately for each vesting tranche on a ratable basis over the requisite service period. The requisite service period for PSUs is based on an analysis of vesting requirements and performance conditions for the particular award. Certain employees are entitled to acceleration of vesting of a portion of their awards upon retirement, subject to age, service and notice requirements (“Retirement Policy”). Stock-based awards falling into the scope of the Retirement Policy are accounted for as a modification of existing awards under ASC Topic 718, Compensation – Stock Compensation. The modifications do not result in the recognition of incremental compensation cost, however, they do result in a new estimate of the requisite service period, which we reassess at each balance sheet date. For the ESPP, the requisite service period is generally the period of time from the offering date to the purchase date. Forfeitures are accounted for as they occur.

Comprehensive (Loss) Income

Comprehensive (loss) income is defined as a change in equity during a period from transactions and other events and circumstances from non-owner sources. Comprehensive (loss) income is made up of net (loss) income plus net unrealized gain (loss) on marketable investment securities, which is our only other item of other comprehensive (loss) income.

Recently Adopted Accounting Pronouncements and Accounting Pronouncements Yet to be Adopted

In December 2023, the FASB issued Accounting Standards Update (“ASU”) No. 2023-09, Income Taxes (Topic 740)—Improvements to Income Tax Disclosures (“ASU 2023-09”), which is intended to enhance the transparency and decision usefulness of income tax disclosures. The amendments in ASU 2023-09 provide for enhanced income tax information primarily through changes to the rate reconciliation and income taxes paid information. The guidance was effective for public entities for fiscal years beginning after December 15, 2024. We adopted ASU 2023-09 prospectively in fiscal year 2025 for the annual reporting period ending December 31, 2025. For additional information on our tax disclosure, see Note 15.

Accounting Pronouncements Yet to be Adopted

In November 2024, the FASB issued ASU No. 2024-03, Income Statement—Reporting Comprehensive Income (Subtopic 220-40)—Expense Disaggregation Disclosures: Disaggregation of Income Statement Expenses (“ASU 2024-03”), which specifies additional disclosure requirements. The amendments in ASU 2024-03 require disclosure about the composition of certain income expense line items, such as purchases of inventory, employee compensation, and other expenses, as well as disclosure about selling expenses. The ASU is effective for fiscal years beginning after December 15, 2026, and interim periods beginning after December 15, 2027. Early adoption is permitted. We are currently evaluating the impact this update will have on the consolidated financial statements and disclosures.

In July 2025, the FASB issued ASU No. 2025-05, Financial Instruments—Credit Losses (Topic 326): Practical Expedient for Certain Current Receivables (“ASU 2025-05”), which provides a practical expedient for estimating expected credit losses on current accounts receivable and contract assets arising from transactions under ASC 606. The practical expedient allows entities to assume that current conditions remain unchanged over the remaining life of the receivables. ASU 2025-05 is effective for annual periods beginning after December 15, 2025, including interim periods within those annual periods. Early adoption is permitted. We are currently evaluating the impact this update will have on the consolidated financial statements and disclosures.

We have evaluated all other recently issued, but not yet effective, accounting pronouncements and do not believe that these accounting pronouncements will have any material impact on the consolidated financial statements or disclosures upon adoption.