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Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

You should read the following discussion and analysis of financial condition and results of operations together with our consolidated financial statements and related notes included elsewhere in this Annual Report on Form 10-K. This discussion and other parts of this Annual Report on Form 10-K contain forward-looking statements that involve risk and uncertainties, such as statements of our plans, objectives, expectations and intentions. Our actual results, performance or achievements could differ materially from any future results, performance or achievements discussed in these forward-looking statements. Factors

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that could cause or contribute to such differences include, but are not limited to, those discussed in the section titled “Risk Factors.”

Overview

Castle Biosciences is improving health through innovative tests that guide patient care. For the diseases that our portfolio of tests cover, we believe the traditional approach to developing a treatment plan for cancers and other diseases using clinical and pathology factors alone is inadequate and can be improved by incorporating the personalized information our diagnostic and prognostic tests provide.

We currently market five proprietary MAAAs, designed to answer clinical questions in dermatologic cancers, UM and BE. Our revenue is primarily generated by our DecisionDx®-Melanoma risk stratification test for cutaneous melanoma and our DecisionDx®-UM risk stratification test for UM.

The foundation of our business is our dermatologic cancer franchise, and our lead product is DecisionDx-Melanoma,a proprietary risk stratification GEP test that predicts the risk of metastasis, or recurrence for patients diagnosed with invasive cutaneous melanoma, a deadly skin cancer. In the management of melanoma, as with nearly all diseases, treatment plans are directed by patient risk-stratification. This test has two distinct, complementary clinically actionable uses. The first revolves around predicting the likelihood of having a SLN negative biopsy result so that physicians and patients can discuss the risk and benefit of undergoing the SLNB surgical procedure. The second use is to inform the appropriate treatment plan during the initial five years post-diagnosis, regardless of the decision to undergo or avoid invasive SLNB surgery. In a typical year, we estimate approximately 130,000 patients are diagnosed with invasive cutaneous melanoma in the United States. We launched DecisionDx-Melanoma in May 2013. Based on the substantial clinical evidence that we have developed, we have received Medicare coverage for DecisionDx-Melanoma, which represents approximately 50% of the addressable patient population for this test.

On August 31, 2020, we commercially launched our SCC proprietary GEP test, DecisionDx®‐SCC, for use in patients with one or more risk factors (also referred to as “high-risk” SCC). On November 2, 2020, we commercially launched our proprietary GEP test for difficult-to-diagnose melanocytic lesions, DecisionDx® DiffDxTM-Melanoma for use in patients with a melanocytic lesion and uncertainty related to the malignancy of the lesion. We believe that these two additional skin cancer tests address areas of high clinical need in dermatological cancer and, together, represent an estimated addressable population of approximately 500,000 patients in the United States.

We further expanded our commercially available dermatologic portfolio in May 2021 when we acquired the myPath Laboratory from Myriad Genetics, Inc. for a cash purchase price of $32.5 million. myPath Melanoma is a clinically validated GEP test that addresses the same unmet clinical need as our DecisionDx DiffDx-Melanoma test. Today, we offer both our myPath Melanoma test and our DecisionDx DiffDx-Melanoma test under an offering that we refer to as our CDO of molecular testing solutions. By offering both of these tests in a single offering, we believe we have demonstrated the ability to improve the test result performance for patients with difficult-to-diagnose melanocytic lesions.

In 2021, we announced the launch of our innovative pipeline initiative to develop a genomic test aimed at predicting response to systemic therapy in patients with moderate to severe psoriasis, atopic dermatitis and related inflammatory skin conditions. In the U.S. alone, there are approximately 18 million patients diagnosed with psoriasis and atopic dermatitis. Approximately 450,000 of these patients annually are eligible for systemic therapies. If successful, this inflammatory skin disease pipeline test has the potential to add approximately $1.9 billion to our current estimated U.S. TAM. In 2021, we initiated a 4,800 patient, prospective, multi-center clinical study to develop and validate this pipeline test and have 50 committed centers, out of the initial target of 50. Based upon our current development and validation timelines, we expect to commercialize this pipeline test by the end of 2025.

In addition to our dermatologic franchise, we also market a test for patients diagnosed with UM, a rare cancer of the eye. DecisionDx®-UM is a proprietary, risk stratification GEP test that predicts the risk of metastasis for patients with UM. We believe DecisionDx-UM is the standard of care in the management of newly diagnosed UM in the majority of ocular oncology practices in the United States. We launched DecisionDx-UM in January 2010. Based on the substantial clinical evidence that we have developed, we received Medicare coverage for DecisionDx-UM, which represents approximately 50% of the addressable patient population.

In December 2021, we extended our commercial portfolio of proprietary tests into the gastroenterology market through our acquisition of Cernostics and the TissueCypher® platform. The TissueCypher platform focuses on unlocking, in the case of the initial test for use in patients with BE, the importance of the location of the expression of proteins or lack thereof within the morphology of the disease (also known as spatialomics). This “spatialomic” information is then interpreted using artificial intelligence approaches to predict the likelihood of progression to high-grade dysplasia and/or esophageal cancer in patients with non-dysplastic, indefinite or low-grade dysplasia BE. We believe the addition of expertise in the spatialomics area

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positions us for continued growth and success in the diagnostics space, complementing our first-to-market dermatologic franchise and our proprietary test for UM.

The number of test reports we generate is a key indicator that we use to assess our business. A test report is generated when we receive a sample in our laboratory, and then the relevant test information is entered into our Laboratory Information Management System, the expression of the biomarkers is measured, then a proprietary algorithmic analysis of the combined biomarkers is performed to generate a report providing the results of that analysis, which is sent to the clinician who ordered the test. The numbers of GEP test reports delivered by us during the years ended December 31, 2021 and 2020 are presented in the table below:

Proprietary Dermatologic GEP Tests

(1)We commercially launched DecisionDx-SCC on August 31, 2020.

(2)Includes DecisionDx DiffDx-Melanoma, which we commercially launched on November 2, 2020, and myPath Melanoma, which we began offering following our acquisition of Myriad myPath Laboratory on May 28, 2021. We offer both our myPath Melanoma and DecisionDx DiffDx-Melanoma under our CDO.

For the year ended December 31, 2021, our dermatologic test report volume increased by 57.8%, reflecting growth in DecisionDx-Melanoma as well as the full year availability of DecisionDx-SCC and DecisionDx DiffDx-Melanoma (now offered as part of CDO). For a discussion of how we recognize revenue derived from our GEP tests, refer to “Net Revenues” under “Components of Results of Operations” below.

The principal focus of our current commercial efforts is to educate clinicians and pathologists on the value of our molecular diagnostic testing products through our direct sales force in the U.S. In dermatology, we began 2020 with 32 outside sales territories. In the third quarter of 2020, we expanded our dermatologic commercial team to create a dedicated sales force of ten territories to support the launch of our DecisionDx Diff-Dx Melanoma test to dermatopathologists. During the first half of 2021, we folded this dedicated team into our existing sales team and completed a further expansion, bringing our dermatologic sales force to the mid-60s. In connection with our acquisition of Cernostics in December 2021, we hired an initial commercial team of approximately 14 outside sales territories, along with commensurate internal sales associates and medical science liaisons, to support our launch of the TissueCypher Barrett’s Esophagus Assay. This dedicated team focuses on gastroenterology specialists that diagnose and manage patients with BE. However, we will continue to evaluate our mix of outside sales territories, inside sales support, marketing and medical affairs in the context of our dermatologic tests and gastroenterology tests and adjust our investments based upon these evaluations.

We continue to see new clinicians order our dermatologic tests for the first time. For the year ended December 31, 2021, we saw approximately 1,938 new ordering clinicians for our dermatologic tests compared to 1,396 during the same period of 2020. Total ordering clinicians for our dermatologic tests were approximately 5,900 for the year ended December 31, 2021.

For additional information on the metrics we disclose, refer to “Information about certain metrics” below.

In developing our DecisionDx-SCC and DecisionDx DiffDx-Melanoma tests, we believed that in addition to addressing significant unmet clinical needs, we would see strategic opportunities for leverage, as many of the clinicians currently ordering DecisionDx-Melanoma would likely be the same clinicians who would find value in these other skin cancer tests. For example,

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we found that for the year ended December 31, 2021, approximately 78% of all clinicians ordering DecisionDx-SCC had also ordered our DecisionDx-Melanoma test during that same period.

We bill third-party payors and patients for the tests we perform. The majority of our revenue collections is paid by third-party insurers, including Medicare. We have received LCDs, which provide coverage for our DecisionDx-Melanoma, myPath Melanoma and DecisionDx-UM tests that meet certain criteria for Medicare and Medicare Advantage beneficiaries, representing approximately 60 million covered lives. In 2022, DecisionDx-UM has received coverage from United Healthcare that will represent approximately 43 million covered lives. A ‘‘covered life’’ means a subscriber, or a dependent of a subscriber, who is insured under an insurance carrier’s policy.

Palmetto, the MAC responsible for administering MolDX, the program that assesses molecular diagnostic technologies, issued a final expanded LCD for DecisionDx-Melanoma, effective November 22, 2020. With this expanded LCD and the accompanying billing and coding articles, we estimate that a significant majority of the DecisionDx-Melanoma tests performed for Medicare patients will meet the coverage criteria. Noridian, the MAC responsible for administering claims for laboratory services performed in Arizona, has adopted the same coverage policy as Palmetto and also issued an expanded final LCD for DecisionDx-Melanoma, effective December 6, 2020.

Separately, Palmetto issued a final LCD for DecisionDx-UM, which became effective in July 2017, and Noridian issued a similar LCD that became effective in September 2017. The Noridian LCD provides for coverage to determine metastatic risk in connection with the management of a patient’s newly diagnosed uveal melanoma and to guide surveillance and referral to medical oncology for those patients. Similar to cutaneous melanoma, the median age at diagnosis for uveal melanoma is estimated at 58-62 years old, therefore the Medicare eligible population represents close to 45% of the addressable market.

On May 17, 2019, CMS determined that DecisionDx-UM meets the criteria for “existing advanced diagnostic laboratory test” status, also referred to as “existing ADLT” status. For 2020, our rate was set by Noridian, our local MAC, but effective in 2021 our rate is set annually based upon the median private payor rate for the first half of the second preceding calendar year. Our rate for 2021 was $7,776 and will remain at $7,776 for 2022, in each case based on the calculation of the median private payor rate.

Also, on May 17, 2019, CMS determined that DecisionDx-Melanoma meets the criteria for “new ADLT” status. Accordingly, from July 1, 2019 through March 31, 2020, the Medicare reimbursement rate was equal to the initial list price of $7,193. From April 1, 2020 through December 31, 2021, the rate was also $7,193, which was calculated based upon the median private payor rate for DecisionDx-Melanoma from July 1, 2019 to November 30, 2019. CMS has informed us that the rate for 2022 will continue to be $7,193, based on the median private payor rate.

myPath Melanoma is currently covered under a MolDX LCD policy through Noridian that oversees laboratories in both Utah and Arizona. Noridian issued an LCD that became effective in June 2019. On September 6, 2019, myPath Melanoma was approved as a new ADLT. The rate for 2022 will be $1,950.

TissueCypher is performed in our Pittsburgh, Pennsylvania laboratory and falls under the Medicare jurisdiction that is managed by Novitas. Novitas previously reviewed TissueCypher and we are receiving payments for claims according to the CLFS. For 2022, CMS published in its CLFS a payment amount of $2,513 for the test.

Beginning in 2023, the rates for DecisionDx-Melanoma, DecisionDx-UM, and myPath Melanoma tests will be set annually based upon the median private payor rate for the first half of the second preceding calendar year. For example, the rate for 2023 will be set using median private payor rate data from January 1, 2021 to June 30, 2021.

In the second quarter of 2020, we submitted our technical assessment dossier for DecisionDx-SCC to Palmetto and Noridian. The dossier was accepted as complete in the third quarter of 2020. In early 2021, we submitted our technical assessment dossier for DecisionDx DiffDx-Melanoma. The dossier was accepted as complete in the first quarter of 2021. We expect that draft LCDs for DecisionDx-SCC and DecisionDx DiffDx-Melanoma could potentially be posted by the end of the second quarter of 2022 resulting in potentially final LCDs effective in 2023. However, there is no assurance that the timing of any draft or final LCD will match our expectations or our historical experience with LCDs for our other tests.

In the second quarter of 2021, Palmetto and the other MACs that participate in the MolDX program posted a revised draft LCD for DecisionDx-Melanoma. The draft LCD includes commentary about two publications regarding the clinical utility of GEP tests and was posted to give providers an opportunity to comment. Each of the draft LCDs include an assessment stating that the MAC does not believe that the new data is sufficient to change the coverage criteria. We have submitted comments on the draft LCD. The comment period on the last of these draft LCDs closed on August 8, 2021. We are unable to predict when the final draft LCD will be posted.

Since becoming a public company, we have financed our operations with the revenue generated from the sale of our products, proceeds from our July 2019 IPO, follow-on public offerings of common stock in June 2020 and December 2020 and bank debt, which has since been repaid in full. We believe that our existing cash and cash equivalents and anticipated cash generated

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from sales of our products will be sufficient to fund our operations for the next 12 months and into the foreseeable future. However, we have based these estimates on assumptions, including those related to the impact of COVID-19 on our financial condition, that may prove to be wrong, and could result in us depleting our capital resources sooner than expected.

Our net (loss) income may fluctuate significantly from period to period, depending on the timing of our planned development activities, the growth of our sales and marketing activities and the timing of revenue recognition under ASC 606. We expect our expenses will increase substantially over time as we:

•execute clinical studies to generate evidence supporting our current and future product candidates;

•execute our commercialization strategy for our current and future commercial products;

•continue our ongoing and planned development of new products in our pipeline;

•seek to discover and develop additional product candidates;

•hire additional scientific and research and development staff; and

•add additional operational, financial and management information systems and personnel.

Furthermore, we expect to continue to incur additional costs associated with operating as a public company, including significant legal, accounting, investor relations and other expenses.

Impact of COVID-19 Pandemic

We are continuing to closely monitor the impact of the COVID-19 pandemic on our business and taking proactive efforts designed to protect the health and safety of our workforce, continue our business operations and advance our corporate objectives. We are providing the following update with respect to the impact of COVID-19 on our business:

•We have maintained, and expect to continue to maintain, uninterrupted business operations with adequate access to reagents and consumables needed for testing patient samples and normal turnaround times for our delivery of test reports. We have continued to maintain our previously implemented adjustments to our operations designed to keep employees safe and comply with federal, state and local guidelines, including those regarding social distancing.

•Following the onset of the COVID-19 pandemic, we experienced declines in orders and test report volume. For example, in the second quarter of 2020, test reports delivered for our lead product, DecisionDx-Melanoma, decreased 18.5% compared to the second quarter of 2019. For the year ended December 31, 2020, our growth in DecisionDx-Melanoma test report volume was 4.5%, compared to year-over-year growth of 29.1% for the year ended December 31, 2019. Our analysis of third-party data indicates that cutaneous melanoma diagnoses for the year ended December 31, 2020 were down approximately 20% compared to the year ended December 31, 2019. In the first quarter of 2021, test reports delivered for DecisionDx-Melanoma decreased by 11.2% compared to the first quarter of 2020. We believe these decreases in our test report volume were linked to delays and/or cancellations in patient visits, resulting in fewer diagnostic biopsies and thus a reduction in the number of diagnoses of cutaneous melanoma in response, as well as the cumulative impact on promotional responsiveness as a result of reduced sales calls per day and in-person sales call during the COVID-19 pandemic.

•We saw positive trends in orders and test report volumes in the second, third, and fourth quarters of 2021. In the second, third and fourth quarters of 2021, test reports delivered for DecisionDx-Melanoma increased by 70.5%, 25.0% and 32.7%, respectively, compared to the same quarters in 2020.

•Our commercial team uses a combination of in-person, virtual, and non-personal promotional and educational efforts. Since the beginning of 2021, we have seen improvements in the number of promotional calls per day, as well as a continued shift from virtual to in-person sales calls. During the three-months ended December 31, 2021, in-person sales calls accounting for over 90% of all calls during such period. However, we have not yet achieved pre-COVID-19 levels of calls per day per sales representative.

•Our future results will be dependent upon the extent and duration of the COVID-19 crisis, including the emergence and spread of variants of the virus, such as the Omicron variant, and government restrictions, which are beyond our control. Although state and local government restrictions put in place to slow the spread of the virus have been eased in certain locations, restrictions may be reinstated from time to time in various regions depending on the circumstances, potentially impacting the flow of future patient visits as well as access to our sales targets. Even with the easing of state and local restrictions and the availability of vaccinations, patient visits and diagnoses of cutaneous melanoma may be impacted by continued apprehension regarding possible exposure to the virus. For example, our

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analysis of third-party data indicates that cutaneous melanoma diagnoses during the year ended December 31, 2021 remain approximately 11% below the pre-COVID, 2019 levels.

•We continue to believe our cash, cash equivalents and anticipated cash to be generated from sales of our products, will be sufficient to fund our operations for the next 12 months and into the foreseeable future.

As conditions are continuously evolving, we are unable to predict how our future test report volume will be impacted, or the extent to which our results of operations, financial condition or cash flows will be impacted, by the COVID-19 pandemic, or other future public health crises. Accordingly, the test report data presented above is not necessarily indicative of our results of operations that can be expected for future periods. For more information on the potential impact of the COVID-19 pandemic on our business, see the risk factors included under “Risks Related to Our Business” and the other risk factors included in Part I, Item 1A., “Risk Factors,” of this Annual Report on Form 10-K.

Factors affecting our performance

We believe there are several important factors that have impacted, and that we expect will continue to impact, our operating performance and results of operations, including:

•Report volume. We believe that the number of reports we deliver to physicians is an important indicator of the growth of adoption among the healthcare provider community. Our revenue and costs are affected by the volume of testing and mix of customers. Our performance depends on our ability to retain and broaden adoption with existing prescribing physicians, as well as attract new physicians. In the near term, our report volume may be negatively impacted by ongoing developments of the COVID-19 pandemic as discussed above.

•Reimbursement. We believe that expanding reimbursement is an important indicator of the value of our products. Payors require extensive evidence of clinical utility, clinical validity, patient outcomes and health economic benefits in order to provide reimbursement for diagnostic products. Our revenue depends on our ability to demonstrate the value of our products to these payors.

•Gross margin. We believe that our gross margin is an important indicator of the operating performance of our business. Higher gross margins reflect the average selling price of our tests, as well as the operating efficiency of our laboratory operations.

•New product development. A significant aspect of our business is our investment in research and development activities, including activities related to the development of new products. In addition to the development of new product candidates, we believe these studies are critical to gaining physician adoption of new products and driving favorable coverage decisions by payors for such products.

Information about certain metrics

The following provides additional information about certain metrics we have disclosed in this Management’s Discussion and Analysis of Financial Condition and Results of Operation.

Test reports delivered for DecisionDx-Melanoma, DecisionDx-SCC, myPath Melanoma/DecisionDx DiffDx-Melanoma, DecisionDx-UM and TissueCypher Barret’s Esophagus Assay represents the number of completed test reports delivered by us during the reporting period indicated. The period in which a test report is delivered does not necessarily correspond with the period the related revenue, if any, is recognized, due to the timing and amount of adjustments for variable consideration under ASC 606. We use this metric to evaluate the growth in adoption of our tests and to measure against our internal performance objectives. We believe this metric is useful to investors in evaluating the volume of our business activity from period-to-period that may not be discernible from our reported revenues under ASC 606. We also sometimes present, on a limited basis, data on the number of orders received. We believe order data can provide additional insight on current demand trends, particularly during the COVID-19 pandemic and with respect to new product launches, when considered in conjunction with test report volume. However, orders received in a particular period do not necessarily correspond with actual delivered test reports or reported revenues for the same period or subsequent periods.

New ordering clinicians for our dermatologic tests represents the number of clinicians who ordered a dermatologic test from us for the first time during the reporting period specified. Our dermatologic tests consist of DecisionDx-Melanoma, DecisionDx-SCC and our CDO. We believe this metric is useful in evaluating the effectiveness of our sales and marketing efforts in establishing new relationships with clinicians and increasing the adoption of our suite of dermatologic tests. We also believe this metric provides useful information to investors in assessing our ability to expand the use of our dermatologic tests. Since this metric is based upon the reporting period in which an order is placed, it does not necessarily correspond to the reporting period in which a test report was delivered or revenue was recognized.

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Components of the Results of Operations

Net Revenues

We generate revenues from the sale of our products. Currently, our revenues are primarily derived from the sale of DecisionDx-Melanoma and DecisionDx-UM. We bill third-party payors and patients for the tests we perform.

Under ASC 606, we recognize revenue at the amount we expect to be entitled, subject to a constraint for variable consideration, in the period in which our tests are delivered to the treating physicians. We have determined that our contracts contain variable consideration under ASC 606 because the amounts paid by third-party payors may be paid at less than our standard rates or not paid at all, with such differences considered implicit price concessions. Variable consideration is recognized only to the extent it is probable that a significant reversal of revenue will not occur in future periods when the uncertainties are resolved. Variable consideration is evaluated each reporting period and adjustments are recorded as increases or decreases in revenues. Variable consideration for Medicare claims that are not covered by an LCD, including those claims subject to approval by an ALJ at an appeal hearing, is deemed to be fully constrained due to factors outside our influence (i.e., judgment or actions of third parties) and the uncertainty of the amount to be received is not expected to be resolved for a long period of time. For these fully constrained claims, we generally recognize revenue in the period the uncertainty is favorably resolved, if at all. Due to potential future changes in Medicare coverage policies and appeal cycles, insurance coverage policies, contractual rates and other trends in the reimbursement of our tests, our revenues may fluctuate significantly from period-to-period. Additionally, our ability to recognize revenue for our recently launched tests, DecisionDx-SCC and DecisionDx DiffDx-Melanoma, is dependent on the development of reimbursement experience and coverage decisions for these tests. Due to limited reimbursement experience, we are currently recognizing revenues for these two tests on the basis of actual cash collections.

Our ability to increase our revenues will depend on our ability to further penetrate our target markets, and, in particular, generate sales through our direct sales force, develop and commercialize additional tests, obtain reimbursement from additional third-party payors and increase our reimbursement rate for tests performed.

Cost of Sales (exclusive of amortization of acquired intangible assets)

The components of our cost of sales are material and service costs associated with testing samples, personnel costs (including salaries, bonuses, benefits and stock-based compensation expense), electronic medical record set up costs, 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. Costs associated with testing samples are recorded when the test is processed, regardless of whether and when revenues are recognized with respect to that test. As a result, our cost of sales as a percentage of revenues may vary significantly from period-to-period because we do not recognize all revenues in the period in which the associated costs are incurred. We expect cost of sales in absolute dollars to increase as the number of tests we perform increases. Additionally, we expect cost of sales to increase with the expansion of laboratory capacity and staffing in advance of the anticipated growth of our recently launched tests.

Gross margin and gross margin percentage are key indicators we use to assess our business. See the table in “Results of Operations—Comparison of the years ended December 31, 2021 and 2020” for details.

Research and Development

Research and development expenses include costs incurred to develop our genomic tests, collect clinical samples and conduct clinical studies to develop and support our products. These costs consist of personnel costs (including salaries, bonuses, benefits and stock-based compensation expense), prototype materials, laboratory supplies, consulting costs, regulatory costs, electronic medical records set up costs, costs associated with setting up and conducting clinical studies and allocated overhead, including rent, information technology, equipment depreciation and utilities. We expense all research and development costs in the periods in which they are incurred. We expect our research and development expenses to increase in absolute dollars as we continue to invest in research and development activities related to developing enhanced and new products.

We expect to use a portion of our cash and cash equivalents to further support and accelerate our research and development activities, including three important studies that are underway to support our DecisionDx-Melanoma test. The first is the PERSONALize study, in which we are evaluating DecisionDx-Melanoma for interactions with adjuvant therapies. The second is the CONNECTION study, which is collecting long-term outcomes for up to 10,000 patients who have been tested with DecisionDx-Melanoma. The third is the DECIDE study, which is designed to determine the association of GEP test results with SLNB surgical decisions in patients eligible for SLNB as well as to track outcomes for patients who did and did not undergo SLNB. Also, as noted above, we recently initiated a 4,800 patient, prospective, multi-center clinical study to develop, validate and bring to market a pipeline test aimed at predicting response to systemic therapy in patients with moderate to severe psoriasis, atopic dermatitis and related inflammatory skin conditions. We have also initiated two additional disease studies for pipeline tests for new indications.

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Selling, General and Administrative

Selling, general and administrative (“SG&A”) expenses include executive, selling and marketing, legal, finance and accounting, human resources, billing and client services. These expenses consist of personnel costs (including salaries, bonuses, benefits and stock-based compensation expense), direct marketing expenses, audit and legal expenses, consulting costs, training and medical education activities, payor outreach programs and allocated overhead, including rent, information technology, equipment depreciation, and utilities. We expect continued increases in SG&A expenses related to compliance with the rules and regulations of the SEC and Nasdaq (in particular as we no longer qualify as an emerging growth company and a smaller reporting company, and have become a large accelerated filer), investor relations activities and additional insurance expenses. Other administrative and professional services expenses within SG&A are expected to increase with the scale of our business, but selling and marketing-related expenses are expected to increase significantly, consistent with our growth strategy.

Amortization of Acquired Intangible Assets

Amortization of acquired intangible assets are primarily associated with developed technology.

Other Operating Income

Other operating income consists of an automatic payment received from HHS for provider relief funds pursuant to the CARES Act.

Interest Income

Interest income consists primarily of earnings on cash and cash equivalents, primarily money market funds.

Interest Expense

Interest expense is primarily attributable to borrowings under our term debt, which was fully repaid in December 2020, and also includes the related amortization of debt discount and issuance costs.

Loss on Extinguishment of Debt

The loss on extinguishment of debt is associated with the early repayment of our term loan facility in December 2020.

Income Tax (Benefit) Expense

In connection with our acquisition of Cernostics in December 2021, and taking into consideration the additional deferred tax liabilities resulting from such acquisition, we determined that a portion of our valuation allowance should be reduced, which was reflected in our income tax benefit for the year ended December 31, 2021. Our consolidated financial statements do not reflect any federal or state income tax benefits attributable to the net losses we have incurred, due to the uncertainty of realizing a benefit from those items. As of December 31, 2021, we had federal NOL carryforwards of $99.4 million, of which $43.5 million will begin to expire in 2030 if not utilized to offset federal taxable income, and $55.9 million may be carried forward indefinitely. Also, as of December 31, 2021, we had state NOL carryforwards of $67.5 million, which begin to expire in 2028 if not utilized to offset state taxable income.

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Results of Operations

Certain prior year amounts in the tables below have been reclassified to conform to the current year presentation. Specifically, we no longer present gross margin on the face of our financial statements and therefore the cost of sales line is now presented within the operating expenses section. This reclassification had no impact on operating loss, loss before income taxes or net loss.

Comparison of the Years Ended December 31, 2021 and 2020

The following table summarizes our results of operations for the periods indicated (in thousands, except percentages):

Years Ended December 31, Change

Operating expenses and other operating income:

Amortization of acquired intangible assets 1,958 — 1,958 NA(1)

(1) NA = Not applicable

(2) NM = Not meaningful

The following table indicates the amount of stock-based compensation expense reflected in the line items above (in thousands):

Years Ended December 31,

The following table provides a disaggregation of net revenues by type (in thousands):

Years Ended December 31,

(1)Dermatologic includes DecisionDx-Melanoma, DecisionDx-SCC and CDO.

(2)Other consists primarily of DecisionDx-UM.

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The following table presents the calculation of gross margin (in thousands, except percentages):

Years Ended December 31,

Less: Amortization of acquired intangible assets 1,958 — 1,958

Gross margin percentage 81.1 % 84.5 % (3.4) %

Net Revenues

Net revenues increased by $31.4 million, or 50.2%, to $94.1 million for the year ended December 31, 2021, primarily due to higher revenues from our dermatologic tests, which increased by $28.1 million. The higher dermatologic test revenue was primarily attributable to higher volume from DecisionDx-Melanoma, which increased 25.2%, higher per-unit revenues for DecisionDx-Melanoma, which reflect the expanded LCD for the test that became effective in the fourth quarter of 2020, and increased revenues from DecisionDx-SCC and our CDO. We believe the higher test report volume for DecisionDx-Melanoma during the year ended December 31, 2021 reflects the relaxing of COVID-19 restrictions, and the related positive impacts on the flow of patient visits, as well as the effects of our sales force expansions discussed above. Revenues from other tests (non-dermatologic) contributed $3.3 million to the overall increase in net revenues for the year ended December 31, 2021. This increase was principally due to the significantly higher Medicare rate for DecisionDx-UM that became effective January 1, 2021 and, to a lesser extent, the effect of a 16.0% increase in DecisionDx-UM test report volume. We believe the higher test report volume for DecisionDx-UM during the year ended December 31, 2021 is due in part to patients making up for missed eye exams from 2020 due to COVID-19 impacts. Net revenues include positive revenue adjustments related to tests delivered in previous periods, associated with changes in estimated variable consideration, of $3.3 million for the year ended December 31, 2021 compared to $0.2 million for the year ended December 31, 2020. The year-over-year increase is primarily attributable to favorable adjustments related to the settlement and collection during the year ended December 31, 2021 of certain groups of receivables from prior years.

Cost of Sales (exclusive of amortization of acquired intangible assets)

Cost of sales (exclusive of amortization of acquired intangible assets) for the year ended December 31, 2021 increased by $6.1 million, or 63.4%, compared to the year ended December 31, 2020, primarily due to higher personnel costs due to additional headcount in our laboratory testing operations, and increased costs of supplies and services, attributable to the higher activity levels. The additional personnel costs included a year-over-year increase in stock-based compensation expense of $1.0 million. Due to the nature of our business, a significant portion of our cost of sales expenses represent fixed costs associated with our testing operations. Accordingly, our cost of sales expense will not necessarily increase or decrease commensurately with the change in net revenues from period to period. We expect our cost of sales (exclusive of amortization of acquired intangible assets) to continue to increase in future periods as we hire additional laboratory personnel and related resources to support our expected growth in volume for our dermatologic, GI and pipeline tests

Gross Margin

Our gross margin percentage was 81.1% for the year ended December 31, 2021, compared to 84.5% for the same period in 2020. The decrease was largely due to amortization expense associated with our acquired intangible assets. In the near term, we expect that our gross margin percentage will decline as we invest in additional laboratory personnel and related resources to support the anticipated growth in our report volumes for tests in advance of obtaining reimbursement coverage. Additionally, our gross margin percentage will be negatively impacted by amortization of intangible assets associated with recent acquisitions.

Research and Development

Research and development expenses increased by $16.4 million, or 123.6%, for the year ended December 31, 2021, compared to the year ended December 31, 2020, primarily due to increases in personnel costs and costs incurred in our clinical studies. Approximately 55% of the increase is attributable to higher personnel costs, due to expansions in headcount in support of our growth, including higher stock-based compensation expense of $3.0 million compared to 2020. Approximately 27% of the increase was attributable to higher costs for clinical studies, including costs related to the PERSONALize, CONNECTION and DECIDE studies as well as our recently initiated a 4,800 patient, prospective, multi-center clinical study to develop, validate and bring to market a pipeline test for inflammatory skin diseases. Also, during the year ended December 31, 2021, we expanded evidence supporting our portfolio of tests with 15 peer-reviewed publications and initiated our collaboration with

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NCI/SEER. We expect to continue to increase our research and development expenses as we fund ongoing evidence development for our existing products as well as additional pipeline programs.

Selling, General and Administrative

SG&A expense increased by $38.6 million, or 80.2%, for the year ended December 31, 2021 compared to the year ended December 31, 2020. Approximately 67% of the increase is attributable to higher personnel costs, particularly due to increased headcount, which includes salaries, stock-based compensation and bonuses. We expanded our sales organization headcount in the third quarter of 2020 in preparation for the commercial launch of our DecisionDx DiffDx-Melanoma test and further expanded our sales team during the first and second quarters of 2021, bringing our dermatology-facing commercial team to the mid-60s. The higher personnel costs also reflect expanded headcount in our administrative support functions. Stock-based compensation expense included in SG&A expense was $15.2 million for the year ended December 31, 2021 compared to $5.8 million for the year ended December 31, 2020. The remainder of the increase in SG&A expense was primarily associated with training events, travel, professional fees and other general increases. The higher expenses for training events and travel reflect both a higher headcount as well a return to more in-person activities in 2021 as result of easing of COVID-19 restrictions.

Amortization of Acquired Intangible Assets

Amortization of acquired intangible assets was $2.0 million for the year ended December 31, 2021 and was entirely associated with amortization of developed technology attributable to the acquisitions of Myriad myPath, LLC and Cernostics in May 2021 and December 2021, respectively. There was no such amortization during the year ended December 31, 2020. Amortization of acquired intangible assets is projected to be approximately $6.7 million for the year ending December 31, 2022, but may increase in the future to the extent we complete additional acquisitions.

Other Operating Income

Other operating income of $1.9 million for the year ended December 31, 2020 consisted entirely of the automatic payment received from HHS pursuant to the CARES Act for provider relief funds. We initially recognized income attributable to the payment in the second quarter of 2020 based on our expectation of meeting the requirements to retain the funds. However, due a change in requirements of the program in the third quarter of 2020, we reversed this income. However, in the fourth quarter of 2020, a legislative change was enacted affecting the program, under which we concluded it is reasonably assured we will qualify to retain the funds. Accordingly, we recognized the income again in the fourth quarter of 2020. There were no similar transactions during the year ended December 31, 2021. See Note 2 to the consolidated financial statements for additional information.

Interest Income

Interest income decreased by $0.3 million for the year ended December 31, 2021, compared to the year ended December 31, 2020, as a result of lower interest rates, despite our higher average balances of cash and cash equivalents.

Interest Expense

Interest expense was essentially zero for the year ended December 31, 2021 compared to $2.6 million for the year ended December 31, 2020. The decrease is a result of the early termination and repayment of all amounts due on our term loan facility in December 2020.

Loss on Extinguishment of Debt

We recorded an extinguishment loss of $1.4 million during the year ended December 31, 2020 related to the early repayment and termination of our term loan facility. The extinguishment loss was attributable to the write-off of the unamortized discount and issuance costs as well as early termination and prepayment fees. There were no similar transactions during the year ended December 31, 2021.

Income Tax (Benefit) Expense

Income tax (benefit) expense was $(8.7) million for the year ended December 31, 2021 compared to $0.1 million for the year ended December 31, 2020. Substantially all of the income tax (benefit) in the year ended December 31, 2021 was attributable to a reduction in our valuation allowance on net deferred tax assets resulting from our acquisition of Cernostics in December 2021. Specifically, we took into consideration the additional deferred tax liabilities resulting from the acquisition and determined that a portion of our existing valuation allowance should be reduced to offset this liability. Other than this item, the recorded income tax (benefit) expense includes minimal amounts because in both the years ended December 31, 2021 and 2020, the income tax benefit of the net loss was largely offset by corresponding changes in the valuation allowance on net deferred tax assets, as we have determined that it is more likely than not that these benefits will not be realized.

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Stock-Based Compensation Expense

Stock-based compensation expense, which is allocated among cost of sales, research and development expense and SG&A expense, totaled $21.7 million for the year ended December 31, 2021 compared to $8.3 million for the year ended December 31, 2020, which we attribute in part to the addition of 144 employees in 2021, a 71.6% increase from 2020. We expect material increases in stock-based compensation expense in future periods, reflecting additional awards outstanding due to expected growth in our headcount. As of December 31, 2021, the total unrecognized stock-based compensation cost related to outstanding awards was $99.3 million, which is expected to be recognized on a straight-line basis over a weighted-average period of 3.3 years.

Liquidity and Capital Resources

Sources of Liquidity

Our principal sources of liquidity are our cash and cash equivalents and cash generated from the sale of our products. As of December 31, 2021 and 2020, we had cash and cash equivalents of $329.6 million and $409.9 million, respectively. In addition to the revenue generated from the sale of our commercial products, we have financed our operations through our IPO in July 2019, two follow-on public offerings of common stock in June 2020 and December 2020, and a $25.0 million secured term loan credit facility, which we repaid in full in December 2020.

On December 14, 2020, we filed an automatically effective shelf registration statement on Form S-3 (File No. 333-251331) with the SEC as a “well-known seasoned issuer.” The registration statement allows us to issue an indeterminate number or amount of common stock, preferred stock, debt securities and warrants from time-to-time in one or more offerings. However, there can be no assurance that we will complete any such offerings of securities. Any future offerings under this registration statement will be dependent upon, among other factors, market conditions, available pricing, our financial condition, investor perception of our prospects, our capital needs and our ability to maintain status as a well-known seasoned issuer.

Public Offerings of Common Stock

On June 29, 2020 and July 2, 2020, we issued and sold 2,000,000 and 300,000 shares of our common stock, respectively, of our common stock in a follow-on public offering at a price of $37.00 per share. We received $79.5 million in aggregate net proceeds, after deducting underwriting discounts and commissions and offering costs. The shares issued and sold on July 2, 2020 reflect the underwriters’ exercise in full of their 30-day option to purchase additional shares at the public offering price, less underwriting discounts and commissions.

On December 18, 2020, we issued and sold 4,600,000 shares of our common stock (including the exercise in full by the underwriters of their option to purchase an additional 600,000 shares) in a follow-on public offering at a price of $58.00 per share. We received $250.5 million in aggregate net proceeds, after deducting underwriting discounts and commissions and offering costs (excluding $0.4 million in offering costs that were incurred but not paid as of December 31, 2020). The shares issued and sold includes the underwriters’ exercise in full of their 30-day option to purchase additional shares at the public offering price, less underwriting discounts and commissions. On December 21, 2020, we used a portion of these proceeds to repay, in full, our outstanding term loan credit facility. See “Long-Term Debt” below for additional information.

As mentioned above, we expect to use a portion of these proceeds, as well as the approximately $65.9 million of net proceeds from our IPO in July 2019, to further support and accelerate our research and development activities, including the clinical studies noted above.

Medicare Advance Payment

On April 16, 2020, we received an advance payment of $8.3 million (“the Advance Payment”) from CMS under its Accelerated and Advance Payment Program, which was expanded to provide increased cash flow to service providers during the COVID-19 pandemic. CMS began recoupment of the Advance Payment in April 2021 by applying 25% of the Medicare payments otherwise owed to us against the balance of the Advance Payment. Recoupment of the full amount of the Advance Payment was complete by December 31, 2021.

Material Cash Requirements

Our primary uses of capital are, and we expect will continue to be, compensation and related expenses, clinical research and development services, laboratory operations, equipment and related supplies, legal and other regulatory expenses, general administrative costs and, from time to time, expansion of our laboratory and office facilities in support of our growth. We anticipate that a substantial portion of our cash requirements in the foreseeable future will relate to the further commercialization of our currently marketed products, the development of our future product candidates in our pipeline and the potential commercialization of these pipeline products, should their development be successful.

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In the past 12 months we completed two strategic opportunities, which we funded using our available cash on hand, and in the longer-term may evaluate and consummate other strategic acquisitions of businesses, assets, products or technologies, which we expect to be able to fund from our available cash and cash equivalents. In May 2021 and December 2021, we completed the acquisitions of the Myriad myPath Laboratory for $32.5 million and Cernostics, Inc. for $30.7 million, respectively. In both cases, the source of funding was from our existing cash and cash equivalents. Under the definitive agreement with Cernostics, we have also agreed to pay up to an additional $50 million in cash or our common stock, at our sole discretion, based on the achievement of certain commercial milestones relating to the year ending December 31, 2022. Our liability with respect to the commercial milestone payments will depend on our ability to successfully integrate Cernostics into our suite of commercial product offerings, while future cash requirements arising from any additional strategic acquisitions will depend on, among other things, our identification of a target company with a product offering that we view as complementary to our product offerings. See Note 5 to the consolidated financial statements for additional information on recent acquisitions.

Since our inception, we have generally incurred significant losses and negative cash flows. For the year ended December 31, 2021 we had a net loss of $31.3 million and an accumulated deficit of $93.8 million as of December 31, 2021. Our ability to generate revenue sufficient to achieve profitability will depend heavily on the successful commercialization of our currently marketed products and the products we plan to launch in the future as well as our spending on research and development activities. We expect to incur additional expenses and losses in the future as we invest in the commercialization of our existing products, the development of our future product candidates and the commercialization of our product candidates. Further, we expect that any acquisitions of businesses, products, assets or technologies will also increase our expenses. We believe that our existing cash and cash equivalents and anticipated cash generated from the sale of our commercial products will be sufficient to fund our operations for the next twelve months. We believe we will meet longer-term expected cash requirements and obligations through a combination of existing cash and cash equivalents, anticipated cash generated from sales of our products and issuances of equity securities or debt offerings, including through our shelf registration statement on Form S-3 that became automatically effective in December 2020. However, we have based these estimates on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we expect. There are numerous risks and uncertainties associated with developing genomic tests, including, among others, the uncertainty of:

•successful commencement and completion of clinical study protocols;

•successful identification and acquisition of tissue samples;

•the development and validation of genomic classifiers; and

•acceptance of new genomic tests by physicians, patients and third-party payors.

Because of the numerous risks and uncertainties associated with research, development and commercialization of product candidates, we are unable to estimate our exact working capital requirements. Our future funding requirements will depend on, and could increase significantly as a result of, many factors, including those listed above as well as those listed in the section titled “Risk Factors.”

We do not currently have any committed external source of funds. In the event additional funding is required, we expect that we would use a combination of equity and debt financings, which may not be available to us when needed, on terms that we deem to be favorable or at all. To the extent that we raise additional capital through the sale of equity or convertible debt securities, the ownership interest of our stockholders will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of common stockholders. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making acquisitions or capital expenditures or declaring dividends. Any disruptions to, or volatility in, the credit and financial markets or any deterioration in overall economic conditions may make any necessary debt or equity financing more difficult to obtain, more costly and/or more dilutive. If we are unable to raise additional funds through debt, or equity financings or other arrangements when needed, we may be required to delay, limit, reduce or terminate our product discovery and development activities or future commercialization efforts.

Leases

We have entered into various operating and finance leases, which are primarily associated with our laboratory facilities and office space. Total undiscounted future minimum payment obligations under our operating leases and finance leases as of December 31, 2021 totaled approximately $10.6 million, of which $1.4 million is payable in 2022 and $9.2 million is payable through the end of 2033. The leases expire on various dates through 2033 and provide certain options to renew for additional periods. We expect our lease obligations will increase in the near term as we expand our facilities, operations and headcount in support of the anticipated growth in our portfolio of commercial products and pipeline tests. Refer to Note 9 to the consolidated financial statements for additional information on our leasing arrangements.

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Cash Flows

The following table summarizes our sources and uses of cash and cash equivalents for each of the periods presented (in thousands):

Years Ended December 31,

Net cash (used in) provided by operating activities $ (18,983) $ 9,865

Net cash used in investing activities (66,657) (4,748)

Net cash provided by financing activities 5,421 305,890

Net change in cash and cash equivalents (80,219) 311,007

Cash and cash equivalents, beginning of year 409,852 98,845

Operating Activities

Net cash used in operating activities of $19.0 million for the year ended December 31, 2021 was primarily attributable to the net loss of $31.3 million, deferred income taxes of $8.7 million, recoupment of the Advance Payment of $8.3 million and increases in accounts receivable of $4.6 million, partially offset by stock compensation expense of $21.7 million, increases in accrued compensation of $6.2 million, depreciation and amortization of $3.4 million and increases in other accrued liabilities of $2.3 million.

Net cash provided by operating activities was $9.9 million for the year ended December 31, 2020 and was primarily attributable to net non-cash charges of $10.5 million (consisting of $8.3 million in stock-based compensation expense, $1.4 million of loss on extinguishment of debt, and $0.8 million in amortization of debt discount and issuance costs), the receipt of the Advance Payment of $8.3 million, increases in accrued compensation of $3.3 million and decreases in accounts receivable of $1.7 million, partially offset by the net loss of $10.3 million and increases in prepaid expenses and other current assets of $2.8 million, other assets of $1.4 million and inventory of $1.0 million.

Investing Activities

Net cash used in investing activities for the year ended December 31, 2021 was primarily attributable to our asset acquisitions of Myriad myPath LLC and Cernostics (which collectively totaled $63.2 million) and purchases of property and equipment of $3.5 million.

Net cash used in investing activities for the year ended December 31, 2020 consisted entirely of purchases of property and equipment.

Financing Activities

Net cash provided by financing activities for the year ended December 31, 2021 consisted primarily of $4.2 millionof proceeds from exercise of common stock options and $2.3 million of proceeds from contributions to the employee stock purchase plan, partially offset by payment of employees’ taxes on vested restricted stock units of $0.8 million and payment of common stock offering costs of $0.3 million. We did not complete any public offerings of common stock during the year ended December 31, 2021.

Net cash provided by financing activities for the year ended December 31, 2020 consisted primarily of $330.0 million of proceeds from two public offerings of our common stock (net of underwriting discounts, commissions and issuance costs), $1.6 million of proceeds from contributions to the employee stock purchase plan and $1.6 million of proceeds from exercise of common stock options, partially offset by repayments of term debt, including extinguishment costs, of $27.4 million.

Inflation

We do not believe that inflation has had a material impact on our results of operations during the periods presented. However, recently, the rate of inflation in the U.S. has risen to levels not experienced in decades. We have begun to see some inflationary pressures, primarily in personnel and related costs. The extent of any future impacts from inflation on our business and our results of operations will be dependent upon how long the elevated inflation levels persist and if the rate of inflation were to further increase, neither of which we are able to predict.

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Critical Accounting Estimates

Our consolidated financial statements are prepared in accordance with accounting principles generally accepted in the United States of America. The preparation of our consolidated financial statements and related disclosures requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, costs and expenses, and the disclosure of contingent assets and liabilities in our consolidated financial statements. We base our estimates on historical experience, known trends and events and various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. We evaluate our estimates and assumptions on an ongoing basis. Our actual results may differ from these estimates under different assumptions or conditions.

While our significant accounting policies are described in more detail in Note 2 to our audited consolidated financial statements, we believe that the following accounting policies are those most critical to the judgments and estimates used in the preparation of our consolidated financial statements.

Revenue Recognition

We recognize revenue is recognized in accordance with ASC 606. In accordance with 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 physician, 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.

All of our revenues from contracts with customers are associated with the provision of diagnostic and prognostic testing services. Most of our revenues are attributable to DecisionDx-Melanoma for cutaneous melanoma. We also provide a test for UM, DecisionDx-UM. We launched a test for patients with cutaneous SCC, DecisionDx-SCC in August 2020 and launched a test for use in patients with suspicious pigmented lesions, DecisionDx DiffDx-Melanoma in November 2020. We began offering a test for difficult-to-diagnose melanocytic lesions, myPath Melanoma, following an asset acquisition completed in May 2021 and began offering the TissueCypher® Barrett’s Esophagus Assay for patients with BE following an asset acquisition completed in December 2021. Information on the disaggregation of revenues is included below.

Once we satisfy our performance obligations and bill for the service, the timing of the collection of payments may vary based on the payment practices of the third-party payor and the existence of contractually established reimbursement rates. Most of the payments for our services are made by third-party payors, including Medicare and commercial health insurance carriers. Certain contracts contain a contractual commitment of a reimbursement rate that differs from our list prices. However, absent a contractually committed reimbursement rate with a commercial carrier or governmental program, our diagnostic tests may or may not be covered by these entities’ existing reimbursement policies. In addition, patients do not enter into direct agreements with us that commit them to pay any portion of the cost of the tests in the event that their insurance provider declines to reimburse us. We may pursue, on a case-by-case basis, reimbursement from such patients in the form of co-payments and co-insurance, in accordance with the contractual obligations that we have with the insurance carrier or health plan. These situations may result in a delay in the collection of payments.

The Medicare claims that are covered by policy under an LCD are generally paid at the established rate by our Medicare contractor within 30 days from receipt. Medicare claims that were either submitted to Medicare prior to the LCD’s effective date or are not covered by the terms of the LCD, but meet the definition of being medically reasonable and necessary pursuant to the controlling Section 1862(a)(1)(A) of the Social Security Act are generally appealed and may ultimately be paid at the first (termed “redetermination”), second (termed “reconsideration”) or third level of appeal (de novo hearing with an ALJ). A successful appeal at any of these levels results in payment.

In the absence of LCD coverage or contractually established reimbursement rates, we have concluded that our contracts include variable consideration because the amounts paid by Medicare or commercial health insurance carriers may be paid at less than our standard rates or not paid at all, with such differences considered implicit price concessions. Variable consideration attributable to these price concessions is measured at the expected value using the “most likely amount” method under ASC 606. The amounts are determined by historical average collection rates by test type and payor category taking into consideration the range of possible outcomes, the predictive value of our past experiences, the time period of when uncertainties expect to be resolved and the amount of consideration that is susceptible to factors outside of our influence, such as the judgment and actions of third parties. Such variable consideration is included in the transaction price only to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainties with respect to the amount are resolved. Variable consideration may be constrained and excluded from the transaction price in situations where

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there is no contractually agreed upon reimbursement coverage or in the absence of a predictable pattern and history of collectability with a payor. Variable consideration for Medicare claims that are not covered by an LCD, including those claims subject to approval by an ALJ at an appeal hearing, is deemed to be fully constrained due to factors outside our influence (i.e., judgment or actions of third parties) and the uncertainty of the amount to be received is not expected to be resolved for a long period of time. Variable consideration is evaluated each reporting period and adjustments are recorded as increases or decreases in revenues. Included in revenues for the years ended December 31, 2021 and 2020 were $3,324,000 and $176,000, respectively, of revenue increases associated with changes in estimated variable consideration related to performance obligations satisfied in previous periods. These amounts include (i) adjustments for actual collections versus estimated amounts and (ii) cash collections and the related recognition of revenue in current period for tests delivered in prior periods due to the release of the constraint on variable consideration.

DecisionDx-Melanoma Claims Consolidation

In June 2017, we submitted to OMHA a formal request to participate in a program that OMHA developed with the intent of providing appellants a means to have large volumes of claim disputes adjudicated at an accelerated rate. The program consolidates outstanding claims at the ALJ level and uses a statistical-sampling approach where five ALJs will determine reimbursement results for a sample of claims which are then extrapolated to the universe of claims. Our consolidation includes 2,698 DecisionDx-Melanoma claims dating from 2013 through spring 2017. Hearings were held in April 2019 with a supplemental hearing in May 2019. On March 12, 2020, OMHA issued a decision denying payment on all claims in the consolidation. We have filed an appeal to the decision, although no ruling on such appeal has been issued to date. In accordance with ASC 606 and consistent with prior periods, we have not recognized (fully constrained the variable consideration) any revenues attributable to these claims in our consolidated financial statements pending the outcome of this matter.

Stock-Based Compensation

Stock-based compensation expense for equity instruments issued to employees and non-employees, including stock options, restricted stock units (“RSUs”) and purchase rights issued under our 2019 Employee Stock Purchase Plan (“ESPP”) is measured based on the grant date fair value of the awards. For stock options and purchase rights granted under the ESPP, we estimate the grant date fair value using the Black-Scholes option-pricing valuation model. For RSUs, we use the closing price of our common stock on the date of grant to determine the fair value. We recognize compensation costs on a straight-line basis for all stock-based compensation awards over the requisite service period of the awards, which is generally the awards’ vesting period, typically four years for options and RSUs and the two-year offering period for the ESPP. Forfeitures are accounted for as they occur.

Set forth below is a description of the significant assumptions used in the option pricing model:

•Expected term. The expected term is the period of time that granted options are expected to be outstanding. For stock options, we have set the expected term using the simplified method based on the weighted average of both the period to vesting and the period to maturity for each option, as we have concluded that our stock option exercise history does not provide a reasonable basis upon which to estimate the expected term. For the ESPP, the expected term is the period of time from the offering date to the purchase date.

•Expected volatility. Previously, because of the limited period of time our stock had been traded in an active market, we calculated expected volatility by using the historical stock prices of a group of similar companies looking back over the estimated life of the option or the purchase rights under our ESPP and averaging the volatilities of these companies. In the third quarter of 2021, we adjusted this calculation to include our own stock price on a relative basis to the peer group in the calculation of expected volatility, as our common stock has now been traded in an active market for more than two years.

•Risk-free interest rate. We base the risk-free interest rate used in the Black-Scholes valuation model on the market yield in effect at the time of option grant and at the offering date for ESPP provided from the Federal Reserve Board’s Statistical Releases and historical publications from the Treasury constant maturities rates for the equivalent remaining terms.

•Dividend yield. We have not paid, and do not have plans to pay, cash dividends. Therefore, we use an expected dividend yield of zero in the Black-Scholes option valuation model.

The fair value of our common stock is also an assumption used to determine the fair value of stock options. Prior to our IPO, the estimated fair value of our common stock had been determined by our board of directors as of the date of each award, with input from management, considering our most recently available third-party valuations of common stock and our board of directors’ assessment of additional objective and subjective factors that it believed were relevant and which may have changed from the date of the most recent valuation through the date of the grant, which intended all options granted to be exercisable at price per share not less than the per share fair value of our common stock underlying those options on the grant date.

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Subsequent to our IPO, the fair value of our common stock is the closing selling price per share of our common stock as reported on the Nasdaq Global Market on the date of grant or other relevant determination date.

The following table sets forth the assumptions used to determine the fair value of stock options:

Years Ended December 31,

Average expected term (years) 6.1 6

Dividend yield —% —%

The following table sets forth assumptions used to determine the fair value of the purchase rights issued under the ESPP:

Years Ended December 31,

Average expected term (years) 1.2 1.2

Dividend yield —% —%

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. Estimating the useful lives of our intangible assets requires considerable judgment. In determining the estimated useful lives, management considers factors such as historical experience, industry and regulatory factors, competition, patent expirations and commercial plans. If new information becomes available in future periods, we may be required to revise our estimated useful lives. If the revised useful lives are shorter than originally estimated, our future amortization expense will increase.

Contingent Consideration

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. With respect to the additional consideration that may be payable in connection with our acquisition of Cernostics, which was treated as an asset acquisition for accounting purposes, we account for the contingent consideration as liability in accordance with ASC 480, Distinguishing Liabilities from Equity (“ASC 480”), under the guidance for obligations that must or may be settled by issuance of a variable number of shares. In accordance with ASC 480, we record the contingent consideration initially and subsequently at fair value with changes in fair value recorded in the statements of operations and comprehensive loss each period. This liability is classified as a “Level 3” fair value measurement (as defined in Note 11 to our consolidated financial statements) due to the use of significant unobservable inputs and a Monte Carlo simulation to determine its fair value. The Monte Carlo simulation uses projections of the commercial milestones for the applicable period as well as the corresponding targets and approximate timing of payment based on the terms of the arrangement. The analysis also uses assumptions for expected volatility of the financial metrics and a risk-adjusted discount rate. The assumptions and estimates we use in the Monte Carlo simulation require considerable judgment and may change in future periods as a result of new information.

Recent Accounting Pronouncements

Refer to Note 2, ‘‘Summary of Significant Accounting Policies,’’ in the accompanying notes to our consolidated financial statements included in this Annual Report on Form 10-K for a discussion of recent accounting pronouncements.

JOBS Act Accounting Election

Previously, we were an emerging growth company within the meaning of the JOBS Act. Section 107(b) of the JOBS Act provides that an emerging growth company can leverage the extended transition period, provided in Section 102(b) of the JOBS Act, for complying with new or revised accounting standards. However, because the market value of our common stock held by non-affiliates exceeded $700.0 million as of June 30, 2021, we are no longer an emerging growth company effective December 31, 2021. As a result, we now apply public company adoption dates for new or revised accounting standards. Further, we were required to comply with the auditor attestation requirements of Section 404(b) of Sarbanes-Oxley regarding our internal control over financial reporting as of December 31, 2021.

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Item 7A. Quantitative and Qualitative Disclosures About Market Risk.

As a smaller reporting company, we are not required to provide the information required by this Item.

Item 8. Financial Statements and Supplementary Data.

The financial statements and supplementary data required by this item are included after the Signature page of this Annual Report on Form 10-K beginning on page F-1.

Item 9. Changes in and Disagreements With Accountants on Accounting and Financial Disclosure.

None.

Item 9A. Controls and Procedures.

Evaluation of Disclosure Controls and Procedures

We maintain “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act, that are designed to ensure that information required to be disclosed in the reports that we file or submit under the Exchange Act is (1) recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms and (2) accumulated and communicated to our management, including our principal executive officer and principal financial officer, to allow timely decisions regarding required disclosure. Management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures.

Our management, with the participation of our Chief Executive Officer and Chief Financial Officer, evaluated the effectiveness of our disclosure controls and procedures as of December 31, 2021. Based upon the evaluation, our Chief Executive Officer and Chief Financial Officer concluded that, as of December 31, 2021, our disclosure controls and procedures were effective at the reasonable assurance level.

Management’s Report on Internal Control over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting as such term as defined in Exchange Act Rule 13a-15(f). Internal control over financial reporting is a process designed under the supervision and with the participation of our management, including our principal executive officer and principal financial officer, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of consolidated financial statements for external purposes in accordance with accounting principles generally accepted in the United States of America.

As of December 31, 2021, our management assessed the effectiveness of our internal control over financial reporting using the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission in Internal Control-Integrated Framework (2013 Framework). Based on this assessment, our management concluded that, as of December 31, 2021, our internal control over financial reporting was effective based on those criteria.

Under guidelines established by the SEC, companies are allowed to exclude acquisitions from their assessment of internal control over financial reporting during the first year of an acquisition while integrating the acquired company. Accordingly, our assessment of internal controls excluded our acquisition of Cernostics, completed on December 3, 2021. See Note 5 to the consolidated financial statements included in this Annual Report on Form 10-K for additional information on our acquisition of Cernostics. Operations from this acquisition represented approximately 13% of our total assets and 0% of our total revenue as of and for the year ended December 31, 2021.

Our independent registered public accounting firm, KPMG LLP, has audited the effectiveness of our internal control over financial reporting as of December 31, 2021, as stated in its report contained in Item 15 of this Annual Report on Form 10-K.

Changes in Internal Control over Financial Reporting

There have been no changes in our internal control over financial reporting (as defined in Rules 13a-15(f) or 15d-15(f) of the Exchange Act) that occurred during the fourth quarter of 2021 that have materially affected, or are reasonably likely to materially affect, the Company’s internal control over financial reporting.

Item 9B. Other Information.

None.

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections.

Not applicable.

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PART III

Certain information required by Part III is omitted from this Annual Report on Form 10-K since we intend to file our definitive proxy statement for our 2022 Annual Meeting of Stockholders (“the Proxy Statement”) pursuant to Regulation 14A of the Exchange Act, not later than 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K, and certain information to be included in the Proxy Statement is incorporated herein by reference.

Item 10. Directors, Executive Officers and Corporate Governance.

The information required by this item is to be included in the Proxy Statement as follows:

•The information relating to our executive officers is to be included in the section entitled “Executive Officers,”

•The information relating to our directors and nominees for director is to be included in the section entitled “Proposal 1: Election of Directors,”

•The information relating to our audit committee and audit committee financial expert is to be included in the section entitled “Information Regarding the Board of Directors and Corporate Governance,” and

•If required, the information regarding compliance with Section 16(a) of the Exchange Act is to be included in the section entitled “Delinquent Section 16(a) Reports.”

Such information will be included in the Proxy Statement and is incorporated herein by reference.

We have adopted a written Code of Business Conduct and Ethics (“Ethics Code”) that applies to all officers, directors and employees, including our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. The Ethics Code is available on our website at www.CastleBiosciences.com. If we make any substantive amendments to the Ethics Code or grant any waiver from a provision of the Ethics Code to any executive officer or director, we will promptly disclose the nature of the amendment or waiver on our website or in a Current Report on Form 8-K.

Item 11. Executive Compensation.

The information required by this item is to be included in our Proxy Statement under the section entitled “Executive Compensation” and is incorporated herein by reference.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.

The information required by this item with respect to equity compensation plans is to be included in our Proxy Statement under the section entitled “Equity Compensation Plan Information” and the information required by this item with respect to security ownership of certain beneficial owners and management is to be included in our Proxy Statement under the section entitled “Security Ownership of Certain Beneficial Owners and Management” and in each case is incorporated herein by reference.

Item 13. Certain Relationships and Related Transactions, and Director Independence.

The information required by this item is to be included in our Proxy Statement under the sections entitled “Transactions with Related Persons and Indemnifications—Related Person Transactions Policy and Procedures” and is incorporated herein by reference.

Item 14. Principal Accountant Fees and Services.

Our independent registered public accounting firm is KPMG LLP, San Diego, CA, Audit Firm ID: 185.

The information required by this item is to be included in our Proxy Statement under the section entitled “Proposal 2: Ratification of Selection of Independent Registered Public Accounting Firm” and is incorporated herein by reference.

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PART IV

Item 15. Exhibit and Financial Statement Schedules.

(a)(1) Financial Statements.

The consolidated financial statements and supplementary data required by this item are included after the Signature page of this Annual Report on Form 10-K beginning on page F-1.

(a)(2) Financial Statement Schedules.

All schedules have been omitted because they are not required or because the required information is given in the Consolidated Financial Statements or Notes thereto.

(a)(3) Exhibits.

The exhibits listed in the Exhibit Index below are filed or incorporated by reference as part of this Annual Report on Form 10-K.

Exhibit Index

Exhibit Number Description of document

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Exhibit Number Description of document

99

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Exhibit Number Description of document

21.1* Subsidiaries of the Registrant.

23.1* Consent of KPMG LLP, Independent Registered Public Accounting Firm.

101.SCH* Inline XBRL Taxonomy Extension Schema.

101.CAL* Inline XBRL Taxonomy Extension Calculation Linkbase.

101.DEF* Inline XBRL Taxonomy Extension Definition Linkbase.

101.LAB* Inline XBRL Taxonomy Extension Label Linkbase.

101.PRE* Inline XBRL Taxonomy Extension Presentation Linkbase.

_____________________________________

* Filed herewith

** Furnished herewith.

+ Indicates management contract or compensatory plan.

# Certain portions of this exhibit (indicated by “[***]”) have been omitted as we have determined (i) the omitted information is not material and (ii) the omitted information would likely cause harm to us if publicly disclosed.

† Schedules and exhibits to the Agreement have been omitted pursuant to Item 601(a)(5) of Regulation S-K. A copy of any omitted schedule and/or exhibit will be furnished to the Securities and Exchange Commission upon request.

^ Pursuant to Item 601(b)(10) of Regulation S-K, certain portions of this exhibit have been omitted (indicated by “[***]”) because the Company has determined that the information is not material and is the type that the Company treats as private or confidential.

Item 16. Form 10-K Summary.

None.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

CASTLE BIOSCIENCES, INC.

Date: February 28, 2022 By: /s/ Derek J. Maetzold

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the Registrant and in the capacity and on the dates indicated.

SIGNATURE TITLE DATE

(Derek J. Maetzold) (Principal Executive Officer)

/s/ Frank Stokes Chief Financial Officer February 28, 2022

(Frank Stokes) (Principal Financial and Accounting Officer)

/s/ Daniel M. Bradbury Chairman of the Board of Directors February 28, 2022

(Daniel M. Bradbury)

/s/ Mara G. Aspinall Member of the Board of Directors February 28, 2022

(Mara G. Aspinall)

/s/ Kimberlee S. Caple Member of the Board of Directors February 28, 2022

(Kimberlee S. Caple)

/s/ G. Bradley Cole Member of the Board of Directors February 28, 2022

(G. Bradley Cole)

/s/ Ellen Goldberg Member of the Board of Directors February 28, 2022

(Ellen Goldberg)

/s/ Miles D. Harrison Member of the Board of Directors February 28, 2022

(Miles D. Harrison)

/s/ Tiffany P. Olson Member of the Board of Directors February 28, 2022

(Tiffany P. Olson)

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INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

Reports of Independent Registered Public Accounting Firm F-2

Consolidated Balance Sheets as of December 31, 2021 and 2020 F-5

Notes to the Consolidated Financial Statements F-10

F-1

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Report of Independent Registered Public Accounting Firm

To the Stockholders and Board of Directors

Castle Biosciences, Inc.:

Opinion on Internal Control Over Financial Reporting

We have audited Castle Biosciences, Inc. and subsidiaries’ (the Company) internal control over financial reporting as of December 31, 2021, based on criteria established in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission. In our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2021, based on criteria established in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of the Company as of December 31, 2021 and December 31, 2020, the related consolidated statements of operations and comprehensive loss, stockholders’ equity, and cash flows for each of the years in the two-year period ended December 31, 2021, and the related notes (collectively, the consolidated financial statements), and our report dated February 28, 2022 expressed an unqualified opinion on those consolidated financial statements.

The Company acquired Cernostics, Inc. during 2021, and management excluded from its assessment of the effectiveness of the Company’s internal control over financial reporting as of December 31, 2021, Cernostics, Inc.’s internal control over financial reporting associated with 13% of total assets and 0% of total revenues included in the consolidated financial statements of the Company as of and for the year ended December 31, 2021. Our audit of internal control over financial reporting of the Company also excluded an evaluation of the internal control over financial reporting of Cernostics, Inc.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting, included in the accompanying Management's Report on Internal Control over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audit also included performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control Over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ KPMG LLP

San Diego, California

February 28, 2022

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Report of Independent Registered Public Accounting Firm

To the Stockholders and Board of Directors

Castle Biosciences, Inc.:

Opinion on the Consolidated Financial Statements

We have audited the accompanying consolidated balance sheets of Castle Biosciences, Inc. and subsidiaries (the Company) as of December 31, 2021 and December 31, 2020, the related consolidated statements of operations and comprehensive loss, stockholders’ equity, and cash flows for each of the years in the two-year period ended December 31, 2021, and the related notes (collectively, the consolidated financial statements). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2021 and December 31, 2020, and the results of its operations and its cash flows for each of the years in the two-year period ended December 31, 2021, in conformity with U.S. generally accepted accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, 2021, based on criteria established in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission, and our report dated February 28, 2022 expressed an unqualified opinion on the effectiveness of the Company’s internal control over financial reporting.

Change in Accounting Principle

As discussed in Note 2 to the consolidated financial statements, the Company has changed its method of accounting for leases as of January 1, 2021 due to the adoption of ASC 842, Leases.

Basis for Opinion

These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on these consolidated financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the consolidated financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of a critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

Measurement of Test Revenue

As discussed in Notes 2 and 3 of the consolidated financial statements, test revenue is recognized when the performance obligation is satisfied, upon delivery of the test report. The amount of revenue recognized reflects the amount of consideration to which the Company expects to be entitled and considers the effects of variable consideration. The measurement of test revenue is determined by contractually established rates as well as historical average collection rates by test type and payor category taking into consideration the range of possible outcomes, the predictive value of the Company’s past experiences, the time period of when uncertainties expect to be resolved and the amount of consideration that is susceptible to factors outside of the Company’s influence, such as the judgment and actions of third parties. The Company reported net revenues of $94,085 thousand for the year ended December 31, 2021, a portion of which related to test revenue.

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We identified the evaluation of the measurement of test revenue as a critical audit matter. Evaluating the measurement of test revenue, specifically the estimation of the amount of test revenue expected to be collectible related to commercial payors and certain others, required especially complex and subjective auditor judgment.

The following are the primary procedures we performed to address this critical audit matter. We evaluated the design and tested the operating effectiveness of certain internal controls related to the estimation of the expected collectible test revenue related to commercial payors and certain others. This included controls related to management’s review of the assumptions and inputs used in the determination of test revenue expected to be collectible from commercial payors and certain others. For a selection of tests, we evaluated certain historical data inputs that are used in management’s model to estimate test revenue expected to be collectible by comparing the data from the model to physician test requisition forms, proof of delivery, and cash collection activity. These data inputs included collection activity, amounts of historical claims, insurance payor categories, test dates, test types, claim aging categories, and revenue recognition dates. In addition, we inquired of the individuals who are responsible for monitoring and tracking the status of anticipated collections to understand the progress of these activities and any impact to management’s estimates.

/s/ KPMG LLP

We have served as the Company’s auditor since 2018.

San Diego, California

February 28, 2022

F-4

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CASTLE BIOSCIENCES, INC.

CONSOLIDATED BALANCE SHEETS

(in thousands, except share and per share data)

December 31,

ASSETS

Current Assets

Prepaid expenses and other current assets 4,807 4,766

Long-term accounts receivable, net 1,308 1,096

Operating lease assets 7,383 —

Intangible assets, net 88,922 —

LIABILITIES AND STOCKHOLDERS’ EQUITY

Current Liabilities

Medicare advance payment — 6,615

Operating lease liabilities 1,179 —

Other accrued and current liabilities 5,678 3,055

Contingent consideration 18,287 —

Noncurrent operating lease liabilities 6,900 —

Noncurrent portion of Medicare advance payment — 1,735

Deferred tax liability 635 —

Commitments and Contingencies (Note 12)

Stockholders’ Equity

Total liabilities and stockholders’ equity $ 462,572 $ 439,328

The accompanying notes are an integral part of these consolidated financial statements.

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CASTLE BIOSCIENCES, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(in thousands, except per share data)

Years Ended December 31,

OPERATING EXPENSES AND OTHER OPERATING INCOME

Amortization of acquired intangible assets 1,958 —

Other operating income — (1,882)

Interest expense (1) (2,634)

Loss on extinguishment of debt — (1,397)

Income tax (benefit) expense (8,720) 84

Net loss and comprehensive loss $ (31,292) $ (10,284)

Loss per share attributable to common stockholders:

Weighted-average shares outstanding:

The accompanying notes are an integral part of these consolidated financial statements.

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CASTLE BIOSCIENCES, INC.

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

(in thousands, except share data)

Shares Amount Shares Amount

Stock-based compensation expense — — — — 8,309 — 8,309

Exercise of common stock warrants — — 241,052 — — — —

Stock-based compensation expense — — — — 21,740 — 21,740

Public offerings of common stock, adjustment to offering costs — — — — 39 — 39

The accompanying notes are an integral part of these consolidated financial statements.

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CASTLE BIOSCIENCES, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(in thousands)

Years Ended December 31,

OPERATING ACTIVITIES

Depreciation and amortization 3,407 472

Amortization of debt discounts and issuance costs — 839

Deferred income taxes (8,736) —

Loss on extinguishment of debt — 1,397

Other — (16)

Change in operating assets and liabilities:

Prepaid expenses and other current assets 617 (2,815)

Operating lease assets 931 —

Operating lease liabilities (852) —

Net cash (used in) provided by operating activities (18,983) 9,865

INVESTING ACTIVITIES

Purchases of property and equipment (3,483) (4,751)

Asset acquisitions, net of cash and cash equivalents acquired (63,184) —

Proceeds from sale of property and equipment 10 3

Net cash used in investing activities (66,657) (4,748)

FINANCING ACTIVITIES

Payment of common stock offering costs (336) —

Repayment of term debt — (27,359)

Proceeds from exercise of common stock options 4,234 1,593

Payment of employees’ taxes on vested restricted stock units (781) —

Proceeds from contributions to the employee stock purchase plan 2,312 1,615

Repayment of principal portion of finance lease liabilities (8) —

Net cash provided by financing activities 5,421 305,890

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CASTLE BIOSCIENCES, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS (Continued)

(in thousands)

Years Ended December 31,

NET CHANGE IN CASH AND CASH EQUIVALENTS (80,219) 311,007

SUPPLEMENTAL DISCLOSURE OF CASH PAID FOR:

DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:

Accrued purchases of property and equipment $ 33 $ 58

Property and equipment acquired with tenant improvement allowance $ 54 $ 714

Asset acquisition, receivable for purchase price adjustment $ 519 $ —

Asset acquisition, liability for contingent consideration $ 18,287 $ —

Common stock offering costs incurred but not paid $ — $ 377

Cashless exercise of common stock warrants $ — $ 250

The accompanying notes are an integral part of these consolidated financial statements.

F-9

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CASTLE BIOSCIENCES, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. Organization and Description of Business

Castle Biosciences, Inc. (the ‘‘Company’’, “we”, “us”, or “our”) was incorporated in the state of Delaware on September 12, 2007. We are a commercial-stage diagnostics company focused on providing physicians and their patients with personalized, clinically actionable information to clinicians and their patients to inform treatment decisions and improve health outcomes. We are based in Friendswood, Texas (a suburb of Houston, Texas) and laboratory operations are conducted at our facilities located in Phoenix, Arizona and in Pittsburgh, Pennsylvania.

Impact of COVID-19 Pandemic

Since the COVID-19 pandemic began in March 2020, we have maintained uninterrupted business operations with normal turnaround times for delivery of test reports, but have experienced declines in test report volume in certain periods, which we believe is linked to delays and/or cancellations in patient visits in response to COVID-19, resulting in reduced diagnostic biopsies and thus reduced diagnoses of cutaneous melanoma. The extent to which COVID-19 may further impact our business, consolidated results of operations, consolidated financial condition and consolidated cash flows will depend on future developments, which are highly uncertain and cannot be predicted with confidence.

2. Summary of Significant Accounting Policies

Basis of Presentation

Our 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’’).All intercompany accounts and transactions have been eliminated in consolidation.

Reclassification

Certain prior year amounts in our consolidated statements of operations and comprehensive loss have been reclassified to conform to the current year presentation. Specifically, we no longer present gross margin on our statements of operations and comprehensive loss and therefore the cost of sales line is now presented within the operating expenses section. This reclassification had no impact on operating loss, loss before income taxes, net loss, comprehensive loss or loss per share.

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 realization of deferred tax assets, the useful lives and recoverability of long-lived assets, the valuation of acquired intangible assets, 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. We have considered the potential impact of the COVID-19 pandemic on our estimates and assumptions. The extent to which the COVID-19 pandemic may impact our estimates in future periods is uncertain and subject to change.

Operating Segments

Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker, or decision-making group, in making decisions on how to allocate resources and assess performance. The Company views its operations and manages its business as one operating segment. All revenues are attributable to U.S.-based operations and all assets are held in the United States.

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CASTLE BIOSCIENCES, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

Cash and Cash Equivalents including Concentrations of Credit Risk

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.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 institutions in which deposits are held. We have not experienced any losses on our cash or cash equivalents.

Revenue Recognition

Revenue is recognized in accordance with Financial Accounting Standards Board (‘‘FASB’’) Accounting Standards Codification (‘‘ASC’’) Topic 606, Revenue from Contracts with Customers (‘‘ASC 606’’). In accordance with 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 physician, 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. See Note 3 for further details.

Accounts Receivable and Allowance for Credit Losses

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

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, 2021 and 2020. Adjustments for implicit price concessions attributable to variable consideration, as discussed above, are incorporated into the measurement of the accounts receivable balances and are not part of the allowance for credit losses.

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 in Friendswood, Texas and Phoenix, Arizona, and are generally being amortized through the end of the lease terms in 2025 and 2033, respectively. Maintenance and repairs are charged to expense as incurred, and material improvements are capitalized. 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 and comprehensive loss 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.

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

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CASTLE BIOSCIENCES, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

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. There were no impairment charges recognized for the years ended December 31, 2021 and 2020.

Acquisitions

We assess acquisitions under ASC 805, Business Combinations, 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. 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.

Contingent Consideration

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. With respect to the additional consideration that may be payable in connection with the Cernostics, Inc. (“Cernostics”) asset acquisition, we account for the contingent consideration as liability in accordance with ASC 480, Distinguishing Liabilities from Equity (“ASC 480”), under the guidance for obligations that must or may be settled by issuance of a variable number of shares. In accordance with ASC 480, we record the contingent consideration initially and subsequently at fair value with changes in fair value recorded in the statements of operations and comprehensive loss each period. For additional information on the contingent consideration, see Notes 5 and 11.

Other Operating Income

On April 10, 2020, we received an automatic payment of $1.9 million from the U.S. Department of Health and Human Services (“HHS”) pursuant to the Coronavirus Aid, Relief and Economic Security Act enacted on March 27, 2020, also known as the CARES Act, out of relief funds allocated by HHS to healthcare providers to reimburse healthcare related expenses or lost revenues attributable to COVID-19. This automatic payment was calculated by HHS in proportion to the providers’ share of Medicare fee-for-service reimbursements in 2019 and was applicable to all facilities and providers that received Medicare fee-for-service reimbursements in 2019. In the second quarter of 2020, based on guidance issued by HHS at the time that stated any reasonable method could be used to calculate lost revenues attributable to COVID-19, we concluded it would qualify to retain the relief funds and recognized the funds received as other operating income during the three months ended June 30, 2020. On September 19, 2020, HHS issued a notice of reporting requirements that changed the methodology for determining lost revenues to be based on a patient care operating income metric, as defined by HHS. Due to this change in methodology and uncertainty in its application, we determined that it was no longer reasonably assured of keeping the funds. Therefore, in the three months ended September 30, 2020, we reversed the previously recognized income. However, in the fourth quarter of 2020, a legislative change was enacted affecting the program, under which we concluded it is reasonably assured we will qualify to retain the funds. Accordingly, we recognized the income again in the fourth quarter of 2020.

Leases

Effective January 1, 2021, we account for leases in accordance with ASC 842, Leases. 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. Periods prior to January 1, 2021 have not been restated for the adoption of ASC 842 and continue to reflect the accounting treatment of leases in accordance with the prior lease accounting guidance, ASC 840, Leases. Under ASC 840, landlord/tenant incentives, rent holidays and escalations in the base price of rent payments under operating leases were recognized on a straight-line basis over the lease term. Deferred rent balances were classified as current or non-current in the consolidated balance sheets based upon the period when reversal of the liability was expected to occur. See Note 9 for details on our leases.

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CASTLE BIOSCIENCES, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

Cost of Sales (exclusive of amortization of acquired intangible assets)

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.

Research and Development

Research and development costs are charged to operations as incurred. Advance payments for goods and services that will be used in future research and development 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 research and development services on behalf of us will be expensed as services are rendered or when the milestone is achieved.

Research and development 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. These 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. The board of directors reviews and evaluates the performance against these objectives and ultimately determines what discretionary payments are made. 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, 2021 and 2020, we accrued approximately $12,071,000 and $7,175,000, respectively, for liabilities associated with these bonus plans. These amounts are classified as current or noncurrent accrued liabilities in the balance sheets 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. For the years ended December 31, 2021 and 2020, we provided a discretionary matching contribution of $2,036,000 and $789,000, respectively. The higher amount for the year ended December 31, 2021 reflects both an increase in the number of employees and a higher matching contribution rate compared to the year ended December 31, 2020.

Income Taxes

We recognize deferred tax assets and liabilities for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using statutory tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the period that includes the statutory enactment date. Valuation allowances are established to reduce deferred tax assets when it is more likely than not that some portion or all of the deferred tax assets will not be realized.

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.

Our policy for recording interest and penalties associated with uncertain tax positions is to record such items as a component of tax expense. No material amounts of tax-related interest or penalties were recorded during the years ended December 31, 2021 and 2020.

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Stock-Based Compensation

Stock-based compensation expense for equity instruments issued to employees is measured based on the grant-date fair value of the awards. The fair value of employee stock options and offerings under the 2019 Employee Stock Purchase Plan (the “ESPP”) are estimated on the date of grant using the Black-Scholes option-pricing valuation model. For restricted stock units (“RSUs”), the fair value is equal to the closing price of our common stock on the date of grant. We recognize compensation costs on a straight-line basis for all employee stock-based compensation awards over the requisite service period of the awards. For options and RSUs, the requisite service period is generally the awards’ vesting period (typically four years). 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

Comprehensive loss is defined as a change in equity during a period from transactions and other events and circumstances from non-owner sources. Our comprehensive loss was the same as our reported net loss for all periods presented.

CARES Act Payroll Tax Deferral

The CARES Act permits employers to defer the payment of the employer share of social security taxes due for the period beginning March 27, 2020 and ending December 31, 2020. Of the amounts deferred, 50% were required to be paid by December 31, 2021 and the remaining 50% are required to be paid by December 31, 2022. We began deferring payment of the employer share of social security taxes in May 2020. Of the $551,000 originally deferred, 50% was repaid during the year ended December 31, 2021. As of December 31, 2021, the remaining $276,000 of such taxes was classified as a current liability on the consolidated balance sheet.

Recently Adopted Accounting Pronouncements

We were previously an emerging growth company (“EGC”) within the meaning of the Jumpstart Our Business Startups Act, as amended, (the “JOBS Act”) and elected to delay the adoption of new or revised accounting pronouncements applicable to public companies until such pronouncements were made applicable to private companies, as permitted under the JOBS Act. Because the market value of our common stock held by non-affiliates exceeded $700.0 million as of June 30, 2021, we ceased to be an EGC effective December 31, 2021. Accordingly, we are no longer permitted to delay the adoption of new or revised accounting pronouncements and as such we adopted the pronouncements discussed below in the fourth quarter of 2021 effective as of the dates noted.

In February 2016, the FASB issued Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842) (“ASU 2016-02”), which supersedes ASC 840, Leases. ASU 2016-02 establishes ASC 842, Leases, andprovides principles for the recognition, measurement, presentation and disclosure of leases for both lessees and lessors. The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification determines whether lease expense is recognized based on an effective interest method for finance leases or on a straight-line basis over the term of the lease for operating leases. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of classification. Leases with a term of 12 months or less may be accounted for similar to existing guidance for operating leases. We adopted ASU 2016-02 and ASC 842 using the modified retrospective approach with an effective date of January 1, 2021. Periods prior to January 1, 2021 have not been restated for the adoption of ASC 842 and continue to reflect the accounting treatment of leases in accordance with ASC 840. In connection with the adoption, we elected the package of practical expedients to not reassess prior conclusions about lease identification, lease classification and capitalized indirect costs. We did not elect the use of hindsight practical expedient. Upon adoption, effective January 1, 2021 we recognized operating lease right-of-use assets of $5,405,000, operating lease liabilities of $6,076,000, reductions to noncurrent liabilities of $751,000, reductions to current assets of $59,000 and a credit to accumulated deficit of $21,000. See Note 9 for disclosures about our leases.

In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which requires the measurement of expected credit losses for financial instruments carried at amortized cost, such as accounts receivable, held at the reporting date based on historical experience, current conditions and reasonable forecasts. The main objective of this ASU is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. We adopted the standard effective January 1, 2021 using the modified retrospective approach. The adoption of this standard had no impact on our consolidated financial statements.

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In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (“ASU 2019-12”), which eliminates certain exceptions to the general principles in Topic 740 and simplifies other areas of the existing guidance. The adoption of ASU 2019-12 effective January 1, 2021 had no impact on our consolidated financial statements.

3. Revenue

All of our revenues from contracts with customers are associated with the provision of diagnostic and prognostic testing services. Most of our revenues are attributable to DecisionDx®-Melanoma for cutaneous melanoma. We also provide a test for uveal melanoma, DecisionDx®-UM. We launched a test for patients with cutaneous squamous cell carcinoma, DecisionDx®-SCC in August 2020 and launched a test for use in patients with suspicious pigmented lesions, DecisionDx® DiffDxTM-Melanoma in November 2020. We began offering a test for difficult-to-diagnose melanocytic lesions, myPath Melanoma, following an asset acquisition completed in May 2021 and began offering the TissueCypher® Barrett’s Esophagus Assay for patients with BE following an asset acquisition completed in December 2021. Information on the disaggregation of revenues is included below.

Once we satisfy our performance obligations and bill for the service, the timing of the collection of payments may vary based on the payment practices of the third-party payor and the existence of contractually established reimbursement rates. Most of the payments for our services are made by third-party payors, including Medicare and commercial health insurance carriers. Certain contracts contain a contractual commitment of a reimbursement rate that differs from our list prices. However, absent a positive coverage policy, with or without a contractually committed reimbursement rate, with a commercial carrier or governmental program, our diagnostic tests may or may not be paid by these entities. In addition, patients do not enter into direct agreements with us that commit them to pay any portion of the cost of the tests in the event that their insurance provider declines to reimburse us. We may pursue, on a case-by-case basis, reimbursement from such patients in the form of co-payments and co-insurance, in accordance with the contractual obligations that we have with the insurance carrier or health plan. These situations may result in a delay in the collection of payments.

The Medicare claims that are covered by policy under a Local Coverage Determination (‘‘LCD’’) are generally paid at the established rate by our Medicare contractor within 30 days from receipt. Medicare claims that were either submitted to Medicare prior to the LCD coverage commencement date or are not covered by the terms of the LCD but meet the definition of being medically reasonable and necessary pursuant to the controlling Section 1862(a)(1)(A) of the Social Security Act are generally appealed and may ultimately be paid at the first (termed ‘‘redetermination’’), second (termed ‘‘reconsideration’’) or third level of appeal (de novo hearing with an Administrative Law Judge (“ALJ”)). A successful appeal at any of these levels results in payment.

In the absence of LCD coverage or contractually established reimbursements rates, we have concluded that our contracts include variable consideration because the amounts paid by Medicare or commercial health insurance carriers may be paid at less than our standard rates or not paid at all, with such differences considered implicit price concessions. Variable consideration attributable to these price concessions is measured at the expected value using the ‘‘most likely amount’’ method under ASC 606. The amounts are determined by historical average collection rates by test type and payor category taking into consideration the range of possible outcomes, the predictive value of our past experiences, the time period of when uncertainties expect to be resolved and the amount of consideration that is susceptible to factors outside of our influence, such as the judgment and actions of third parties. Such variable consideration is included in the transaction price only to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainties with respect to the amount are resolved. Variable consideration may be constrained and excluded from the transaction price in situations where there is no contractually agreed upon reimbursement coverage or in the absence of a predictable pattern and history of collectability with a payor. Accordingly, in such situations revenues are recognized on the basis of actual cash collections. Variable consideration for Medicare claims that are not covered by an LCD, including those claims subject to approval by an ALJ at an appeal hearing, is deemed to be fully constrained due to factors outside our influence (i.e., judgment or actions of third parties) and the uncertainty of the amount to be received is not expected to be resolved for a long period of time. Variable consideration is evaluated each reporting period and adjustments are recorded as increases or decreases in revenues. Included in revenues for the years ended December 31, 2021 and 2020 were $3,324,000 and $176,000, respectively, of revenue increases associated with changes in estimated variable consideration related to performance obligations satisfied in previous periods. These amounts include (i) adjustments for actual collections versus estimated amounts and (ii) cash collections and the related recognition of revenue in current period for tests delivered in prior periods due to the release of the constraint on variable consideration.

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Because our contracts with customers have an expected duration of one year or less, we have elected the practical expedient in ASC 606 to not disclose information about our remaining performance obligations. Any incremental costs to obtain contracts are recorded as selling, general and administrative expense as incurred due to the short duration of our contracts. Contract balances consisted of accounts receivable (both current and noncurrent) as of December 31, 2021 and 2020 and the Medicare advance payment (discussed further below) as of December 31, 2020.

Medicare Advance Payment

On April 16, 2020, we received an advance payment of $8.3 million (the “Advance Payment”) from the Centers for Medicare & Medicaid Services (“CMS”) under its Accelerated and Advance Payment Program, which was expanded to provide increased cash flow to service providers during the COVID-19 pandemic. CMS began recoupment of the Advance Payment in April 2021 by applying 25% of the Medicare payments otherwise owed to us against the balance of the Advance Payment. Recoupment of the full amount of the Advance Payment was complete by December 31, 2021.

DecisionDx-Melanoma Claims Consolidation

In June 2017, we submitted to the Office of Medicare Hearings and Appeals (‘‘OMHA’’) a formal request to participate in a program that OMHA developed with the intent of providing appellants a means to have large volumes of claim disputes adjudicated at an accelerated rate. The program consolidates outstanding claims at the ALJ level and uses a statistical-sampling approach where five ALJs will determine reimbursement results for a sample of claims which are then extrapolated to the universe of claims. The consolidation includes 2,698 DecisionDx-Melanoma claims dating from 2013 through spring 2017. Hearings were held in April 2019 with a supplemental hearing in May 2019. On March 12, 2020, OMHA issued a decision denying payment on all claims in the consolidation. We have filed an appeal to the decision, although no ruling on such appeal has been issued to date. In accordance with ASC 606 and consistent with prior periods, we have not recognized (fully constrained the variable consideration) any revenues attributable to these claims in our consolidated financial statements pending the outcome of this matter.

Disaggregation of revenues

The table below provides the disaggregation of revenue by type (in thousands):

Years Ended December 31,

Payor Concentration

We rely upon reimbursements from third-party government payors (primarily Medicare) and private-payor insurance companies to collect accounts receivable related to sales of our diagnostic tests.

Our significant third-party payors and their related revenues as a percentage of total revenues and accounts receivable balances are as follows:

Year Ended December 31, As of December 31, As of December 31,