Summary of Significant Accounting Policies	3 Months Ended
Mar. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 2. Summary of Significant Accounting Policies Use of Estimates The preparation of financial statements in conformity with 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 financial statements and the reported amounts of expenses during the reporting period. Significant items subject to such estimates and assumptions include those related to revenue recognition, including the returns reserve, valuation of inventory, software development costs, incremental borrowing rates related to lease liability, fair value of the liability component of convertible senior notes, valuation of deferred taxes, and other contingencies. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates. Net Loss per Share Attributable to Common Stockholders The Company follows the two-class method when computing net loss per common share when shares are issued that meet the definition of participating securities. The two-class method determines net loss per common share for each class of common stock and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The two-class method requires income (loss) available or attributable to common stockholders for the period to be allocated between common stock and participating securities based upon their respective rights to receive dividends as if all income for the period had been distributed. The Company’s convertible senior notes are participating securities as they give the holders the right to receive dividends if dividends or distributions declared to the common stockholders is equal to or greater than the last reported sale price of the Company’s common stock on the trading day immediately preceding the ex-dividend date for such dividend or distribution as if the instruments had been converted into shares of common stock. No undistributed earnings were allocated to the participating securities as the contingent event is not satisfied as of the reporting date. For periods in which the Company reports net losses, diluted net loss per common share attributable to common stockholders is the same as basic net loss per common share attributable to common stockholders, because potentially dilutive common shares and assumed conversion of the convertible senior notes are not assumed to have been issued within the calculation, if their effect is anti-dilutive. Revenue Recognition The Company generates revenue from the sale of pre-owned luxury goods through its online marketplace and retail stores. Consignment and Service Revenue The Company provides a service to sell pre-owned luxury goods on behalf of consignors to buyers through its online marketplace and retail stores. The Company retains a percentage of the proceeds received as payment for its consignment service, which the Company refers to as its take rate. The Company reports consignment revenue on a net basis as an agent and not the gross amount collected from the buyer. Title to the consigned goods remains with the consignor until transferred to the buyer upon purchase of the consigned goods and expiration of the allotted return period. The Company does not take title of consigned goods at any time except in certain cases where returned goods become Company-owned inventory. The Company recognizes consignment revenue upon purchase of the consigned good by the buyer as its performance obligation of providing consignment services to the consignor is satisfied at that point. Consignment revenue is recognized net of estimated returns, cancellations, buyer incentives and adjustments. The Company recognizes a returns reserve based on historical experience, which is recorded in other accrued and current liabilities on the condensed balance sheets (see Note 5). Sales tax assessed by governmental authorities is excluded from revenue. Certain transactions provide consignors with a material right resulting from the tiered consignor commission plan. Under this plan, the amount an individual consignor receives for future sales of consigned goods may be dependent on previous consignment sales for that consignor within his/her consignment period. Accordingly, in certain consignment transactions, a small portion of the Company’s consignment revenue is allocated to such material right using the portfolio method and recorded as deferred revenue, which is recorded in other accrued and current liabilities on the condensed balance sheets. The impact of the deferral has not been material to the financial statements. The Company charges shipping fees to buyers and has elected to treat shipping and handling activities performed after control transfers to the buyer as fulfillment activities. All outbound shipping and handling costs are accounted for as fulfillment costs in cost of consignment and service revenue at the time revenue is recognized. The Company also generates subscription revenue from monthly memberships allowing buyers early access to shop for luxury goods. The buyers receive the early access and other benefits over the term of the subscription period, which represents a single stand-ready performance obligation. Therefore, the subscription fees paid by the buyer are recognized over the monthly subscription period. Subscription revenue was not material in the three months ended March 31, 2021 and 2020. Direct Revenue The Company generates direct revenue from the sale of Company-owned inventory. The Company recognizes direct revenue on a gross basis upon shipment of the purchased good to the buyer as the Company acts as the principal in the transaction. Direct revenue is recognized net of estimated returns, buyer incentives and adjustments. Sales tax assessed by governmental authorities is excluded from revenue. Cost of direct revenue is also recognized upon shipment to the buyer in an amount equal to that paid to the consignor from the original consignment sale, an amount equal to that paid as a direct purchase from a third party, or the lower of cost of the inventory purchased and its net realizable value. Incentives Incentives, which include platform-wide discounts and buyer incentives, may periodically be offered to buyers. Platform-wide discounts are made available to all buyers on the online marketplace. Buyer incentives apply to specific buyers and consist of coupons or promotions that offer credits in connection with purchases on the Company’s platform, and do not impact the commissions paid to consignors. These are treated as a reduction of consignment and service revenue and direct revenue. Additionally, the Company periodically offers commission exceptions to consignors to optimize its supply. These are treated as reduction of consignment and service revenue, and are reflected in the Company’s take rate. The Company may offer a certain type of buyer incentive in the form of site credits to buyers on current transactions to be applied towards future transactions, which are included in other accrued and current liabilities on the balance sheets. Contract Liabilities The Company’s contractual liabilities consist of deferred revenue for material rights primarily related to the tiered consignor commission plan, which are recognized as revenue using a portfolio approach based on the pattern of exercise, and certain unredeemed site credits, which were immaterial as of March 31, 2021 and December 31, 2020. Contract liabilities are recorded in other accrued and current liabilities on the balance sheets and are generally expected to be recognized within one year. Contract liabilities were immaterial as of March 31, 2021 and December 31, 2020. Cost of Revenue Cost of consignment and service revenue consist of shipping costs, credit card fees, packaging, customer service personnel-related costs, website hosting services, and consignor inventory adjustments relating to lost or damaged products. Cost of direct revenue consists of the cost of goods sold, credit card fees, packaging, customer service personnel-related costs, website hosting services, and inventory adjustments. Stock-based Compensation Stock-based compensation expense related to employees and nonemployees is measured based on the grant-date fair value of the awards. Compensation expense is recognized in the statements of operations over the period during which the employee is required to perform services in exchange for the award (the vesting period of the applicable award) using the straight-line method. The Company estimates the fair value of stock options granted using the Black-Scholes option pricing model and accounts for forfeitures as they occur. The fair value of restricted stock units (“RSUs”) is estimated based on the fair market value of the Company’s common stock on the date of grant, which is determined based on the closing price of the Company’s common stock. The fair value of each purchase under the employee stock purchase plan (ESPP) is estimated at the beginning of the offering period using the Black-Scholes option pricing model. Cash, Cash Equivalents and Restricted Cash The Company considers all highly liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents. Cash equivalents primarily consist of investments in short-term money market funds and amounts invested in U.S. treasury securities. As of March 31, 2021 and December 31, 2020, the Company had no restricted cash. Short-term Investments The Company has classified and accounted for its short-term investments as available-for-sale which are carried at fair value on its condensed balance sheets. Available-for-sale securities with remaining maturities of 12 months or less are classified as short term and available-for-sale securities with remaining maturities greater than 12 months are classified as long term. Available-for-sale investments are reported at fair value based on quoted market prices and other observable market data. The Company records any unrealized gains and losses within accumulated other comprehensive income (loss) as a component of stockholders’ equity, of which there were none as of March 31, 2021 and December 31, 2020. The Company evaluates its short-term investments periodically for possible impairment. If the Company determines that an investment with an amortized cost basis in excess of estimated fair value is caused by expected credit losses, the expected credit loss on the investment is recognized in Other income and expense, net. As of March 31, 2021 and December 31, 2020, the Company had not recorded any impairments due to credit loss. Inventory Inventory consists of finished goods arising from goods returned after the title has transferred from the buyer to the Company as well as finished goods from direct purchases from vendors and consignors. The cost of inventory is an amount equal to that paid to the consignor or vendors. Inventory is valued at the lower of cost or net realizable value using the specific identification method and the Company records provisions, as appropriate, to write down obsolete and excess inventory to estimated net realizable value. After the inventory value is reduced, adjustments are not made to increase it from the estimated net realizable value. Our provisions to write down obsolete and excess inventory to net realizable value were not material for the three months ended March 31, 2021 and 2020. Return reserves, which reduce revenue and cost of sales, are estimated using historical experience. Liabilities for return allowances are included in other accrued and current liabilities on the condensed balance sheets and were $14.5 million and $18.3 million as of March 31, 2021 and December 31, 2020, respectively. Included in inventory on the Company’s condensed balance sheets are assets totaling $3.4 million and $7.4 million as of March 31, 2021 and December 31, 2020, respectively, for the rights to recover products from customers associated with its liabilities for return reserves. Software Development Costs Proprietary software includes the costs of developing the Company’s internal proprietary business platform and automation projects. The Company capitalizes qualifying proprietary software development costs that are incurred during the application development stage. Capitalization of costs begins when two criteria are met: (1) the preliminary project stage is completed and (2) it is probable that the software will be completed and used for its intended function. Such costs are capitalized in the period incurred. Capitalization ceases and amortization begins when the software is substantially complete and ready for its intended use, including the completion of all significant testing. Costs related to preliminary project activities and post-implementation operating activities are expensed as incurred. Leases Contracts that have been determined to convey the right to use an identified asset are evaluated for classification as an operating or finance lease. For the Company’s operating leases, the Company records a lease liability based on the present value of the lease payments at lease inception, using the applicable incremental borrowing rate. The Company estimates the incremental borrowing rate by developing its own synthetic credit rating, corresponding yield curve, and the terms of each lease at the lease commencement date. The corresponding right-of-use asset is recorded based on the corresponding lease liability at lease inception, adjusted for payments made to the lessor at or before the commencement date, initial direct costs incurred and any tenant incentives allowed for under the lease. The Company does not include optional renewal terms or early termination provisions unless the Company is reasonably certain such options would be exercised at the inception of the lease. Operating lease right-of-use assets, current portion of operating lease liabilities, and operating lease liabilities, net of current portion are included on the Company’s condensed balance sheets. The Company has elected the practical expedients that allows for the combination of lease components and non-lease components and to record short-term leases as lease expense on a straight-line basis on the condensed statements of operations. Variable lease payments are recorded as expense as they are incurred. The Company has finance leases for vehicles and equipment, and the amounts of finance lease right-of-use assets and finance lease liabilities have been immaterial to date. Convertible Senior Notes, net Convertible debt instruments that may be settled in cash or other assets, or partially in cash, upon conversion, are separately accounted for as long-term debt and equity components (or conversion feature). The debt component represents the Company’s contractual obligation to pay principal and interest and the equity component represents the Company’s option to convert the debt security into equity of the Company or the equivalent amount of cash. Upon issuance, the Company allocated the debt component on the basis of the estimated fair value of a similar liability that does not have an associated convertible feature and the remaining proceeds are allocated to the equity component. The bifurcation of the debt and equity components resulted in a debt discount for the aforementioned notes. The Company uses the effective interest method to amortize the debt discount to interest expense over the amortization period which is the expected life of the debt. Capped Call Transactions In June 2020 and March 2021, in connection with the issuance of its convertible senior notes, the Company entered into Capped Call Transactions (see Note 6). The Capped Call Transactions are expected generally to reduce the potential dilution to the holders of the Company’s common stock upon any conversion of the convertible senior notes and/or offset any cash payments the Company is required to make in excess of the principal amount of converted convertible senior notes, with such reduction and/or offset subject to a cap based on the cap price. The capped calls are classified in stockholders’ equity as a reduction to additional paid-in capital and are not subsequently remeasured as long as the conditions for equity classification continue to be met. Debt Issuance Costs Debt issuance costs are amortized to interest expense over the estimated life of the related debt based on the effective interest method. The Company presents debt issuance costs on the condensed balance sheets as a direct deduction from the associated debt. A portion of debt issuance costs incurred in connection with the convertible senior notes issued in June 2020 and March 2021 was related to the equity component and was recorded as a reduction to additional paid in capital and is not amortized to interest expense over the estimated life of the related debt. Concentrations of Credit Risks Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash and cash equivalents, restricted cash, accounts receivable, and investments. At times, such amount may exceed federally-insured limits. The Company reduces credit risk by placing its cash and cash equivalents, restricted cash, and investments with major financial institutions within the United States. As of March 31, 2021 and December 31, 2020, there were no customers that represented 10% or more of the Company’s accounts receivable balance and there were no customers that individually exceeded 10% of the Company’s total revenue for each of the three months ended March 31, 2021 and 2020. Recently Issued Accounting Pronouncements In August 2020, the FASB issued ASU 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging-Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity, which simplifies accounting for convertible instruments. Under this ASU, the embedded conversion features will no longer be separated from the host contract for convertible instruments with conversion features that are not required to be accounted for as derivatives or that do not result in substantial premiums accounted for as paid-in capital. Consequently, a convertible debt instrument will be accounted for as a single liability measured at its amortized cost and a convertible preferred stock will be accounted for as a single equity instrument measured at its historical cost, as long as no other features require bifurcation and recognition as derivatives. ASU 2020-06 removes certain settlement conditions that are required for equity contracts to qualify for the derivative scope exception and it also simplifies the diluted earnings per share calculation in certain areas. The ASU will be effective for annual reporting periods beginning after December 15, 2021 and early adoption is permitted. The Company is currently evaluating the impact of this standard on its financial statements. It is expected that upon adoption, the Company’s Convertible Senior Notes, as discussed in Note 7, will no longer be bifurcated into an equity and a debt component, but rather accounted for as a single liability.

Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2021

Summary of Significant Accounting Policies

Note 2. Summary of Significant Accounting Policies

Use of Estimates

The preparation of financial statements in conformity with 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 financial statements and the reported amounts of expenses during the reporting period. Significant items subject to such estimates and assumptions include those related to revenue recognition, including the returns reserve, valuation of inventory, software development costs, incremental borrowing rates related to lease liability, fair value of the liability component of convertible senior notes, valuation of deferred taxes, and other contingencies. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates.

Net Loss per Share Attributable to Common Stockholders

The Company follows the two-class method when computing net loss per common share when shares are issued that meet the definition of participating securities. The two-class method determines net loss per common share for each class of common stock and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The two-class method requires income (loss) available or attributable to common stockholders for the period to be allocated between common stock and participating securities based upon their respective rights to receive dividends as if all income for the period had been distributed.

The Company’s convertible senior notes are participating securities as they give the holders the right to receive dividends if dividends or distributions declared to the common stockholders is equal to or greater than the last reported sale price of the Company’s common stock on the trading day immediately preceding the ex-dividend date for such dividend or distribution as if the instruments had been converted into shares of common stock. No undistributed earnings were allocated to the participating securities as the contingent event is not satisfied as of the reporting date.

For periods in which the Company reports net losses, diluted net loss per common share attributable to common stockholders is the same as basic net loss per common share attributable to common stockholders, because potentially dilutive common shares and assumed conversion of the convertible senior notes are not assumed to have been issued within the calculation, if their effect is anti-dilutive.

Revenue Recognition

The Company generates revenue from the sale of pre-owned luxury goods through its online marketplace and retail stores.

Consignment and Service Revenue

The Company provides a service to sell pre-owned luxury goods on behalf of consignors to buyers through its online marketplace and retail stores. The Company retains a percentage of the proceeds received as payment for its consignment service, which the Company refers to as its take rate. The Company reports consignment revenue on a net basis as an agent and not the gross amount collected from the buyer. Title to the consigned goods remains with the consignor until transferred to the buyer upon purchase of the consigned goods and expiration of the allotted return period. The Company does not take title of consigned goods at any time except in certain cases where returned goods become Company-owned inventory.

The Company recognizes consignment revenue upon purchase of the consigned good by the buyer as its performance obligation of providing consignment services to the consignor is satisfied at that point. Consignment revenue is recognized net of estimated returns, cancellations, buyer incentives and adjustments. The Company recognizes a returns reserve based on historical experience, which is recorded in other accrued and current liabilities on the condensed balance sheets (see Note 5). Sales tax assessed by governmental authorities is excluded from revenue.

Certain transactions provide consignors with a material right resulting from the tiered consignor commission plan. Under this plan, the amount an individual consignor receives for future sales of consigned goods may be dependent on previous consignment sales for that consignor within his/her consignment period. Accordingly, in certain consignment transactions, a small portion of the Company’s consignment revenue is allocated to such material right using the portfolio method and recorded as deferred revenue, which is recorded in other accrued and current liabilities on the condensed balance sheets. The impact of the deferral has not been material to the financial statements.

The Company charges shipping fees to buyers and has elected to treat shipping and handling activities performed after control transfers to the buyer as fulfillment activities. All outbound shipping and handling costs are accounted for as fulfillment costs in cost of consignment and service revenue at the time revenue is recognized.

The Company also generates subscription revenue from monthly memberships allowing buyers early access to shop for luxury goods. The buyers receive the early access and other benefits over the term of the subscription period, which represents a single stand-ready performance obligation. Therefore, the subscription fees paid by the buyer are recognized over the monthly subscription period. Subscription revenue was not material in the three months ended March 31, 2021 and 2020.

Direct Revenue

The Company generates direct revenue from the sale of Company-owned inventory. The Company recognizes direct revenue on a gross basis upon shipment of the purchased good to the buyer as the Company acts as the principal in the transaction. Direct revenue is recognized net of estimated returns, buyer incentives and adjustments. Sales tax assessed by governmental authorities is excluded from revenue. Cost of direct revenue is also recognized upon shipment to the buyer in an amount equal to that paid to the consignor from the original consignment sale, an amount equal to that paid as a direct purchase from a third party, or the lower of cost of the inventory purchased and its net realizable value.

Incentives

Incentives, which include platform-wide discounts and buyer incentives, may periodically be offered to buyers. Platform-wide discounts are made available to all buyers on the online marketplace. Buyer incentives apply to specific buyers and consist of coupons or promotions that offer credits in connection with purchases on the Company’s platform, and do not impact the commissions paid to consignors. These are treated as a reduction of consignment and service revenue and direct revenue. Additionally, the Company periodically offers commission exceptions to consignors to optimize its supply. These are treated as reduction of consignment and service revenue, and are reflected in the Company’s take rate. The Company may offer a certain type of buyer incentive in the form of site credits to buyers on current transactions to be applied towards future transactions, which are included in other accrued and current liabilities on the balance sheets.

Contract Liabilities

The Company’s contractual liabilities consist of deferred revenue for material rights primarily related to the tiered consignor commission plan, which are recognized as revenue using a portfolio approach based on the pattern of exercise, and certain unredeemed site credits, which were immaterial as of March 31, 2021 and December 31, 2020. Contract liabilities are recorded in other accrued and current liabilities on the balance sheets and are generally expected to be recognized within one year. Contract liabilities were immaterial as of March 31, 2021 and December 31, 2020.

Cost of Revenue

Cost of consignment and service revenue consist of shipping costs, credit card fees, packaging, customer service personnel-related costs, website hosting services, and consignor inventory adjustments relating to lost or damaged products. Cost of direct revenue consists of the cost of goods sold, credit card fees, packaging, customer service personnel-related costs, website hosting services, and inventory adjustments.

Stock-based Compensation

Stock-based compensation expense related to employees and nonemployees is measured based on the grant-date fair value of the awards. Compensation expense is recognized in the statements of operations over the period during which the employee is required to perform services in exchange for the award (the vesting period of the applicable award) using the straight-line method. The Company estimates the fair value of stock options granted using the Black-Scholes option pricing model and accounts for forfeitures as they occur. The fair value of restricted stock units (“RSUs”) is estimated based on the fair market value of the Company’s common stock on the date of grant, which is determined based on the closing price of the Company’s common stock. The fair value of each purchase under the employee stock purchase plan (ESPP) is estimated at the beginning of the offering period using the Black-Scholes option pricing model.

Cash, Cash Equivalents and Restricted Cash

The Company considers all highly liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents. Cash equivalents primarily consist of investments in short-term money market funds and amounts invested in U.S. treasury securities.

As of March 31, 2021 and December 31, 2020, the Company had no restricted cash.

Short-term Investments

The Company has classified and accounted for its short-term investments as available-for-sale which are carried at fair value on its condensed balance sheets. Available-for-sale securities with remaining maturities of 12 months or less are classified as short term and available-for-sale securities with remaining maturities greater than 12 months are classified as long term.

Available-for-sale investments are reported at fair value based on quoted market prices and other observable market data. The Company records any unrealized gains and losses within accumulated other comprehensive income (loss) as a component of stockholders’ equity, of which there were none as of March 31, 2021 and December 31, 2020. The Company evaluates its short-term investments periodically for possible impairment. If the Company determines that an investment with an amortized cost basis in excess of estimated fair value is caused by expected credit losses, the expected credit loss on the investment is recognized in Other income and expense, net. As of March 31, 2021 and December 31, 2020, the Company had not recorded any impairments due to credit loss.

Inventory

Inventory consists of finished goods arising from goods returned after the title has transferred from the buyer to the Company as well as finished goods from direct purchases from vendors and consignors. The cost of inventory is an amount equal to that paid to the consignor or vendors. Inventory is valued at the lower of cost or net realizable value using the specific identification method and the Company records provisions, as appropriate, to write down obsolete and excess inventory to estimated net realizable value. After the inventory value is reduced, adjustments are not made to increase it from the estimated net realizable value. Our provisions to write down obsolete and excess inventory to net realizable value were not material for the three months ended March 31, 2021 and 2020.

Return reserves, which reduce revenue and cost of sales, are estimated using historical experience. Liabilities for return allowances are included in other accrued and current liabilities on the condensed balance sheets and were $14.5 million and $18.3 million as of March 31, 2021 and December 31, 2020, respectively. Included in inventory on the Company’s condensed balance sheets are assets totaling $3.4 million and $7.4 million as of March 31, 2021 and December 31, 2020, respectively, for the rights to recover products from customers associated with its liabilities for return reserves.

Software Development Costs

Proprietary software includes the costs of developing the Company’s internal proprietary business platform and automation projects. The Company capitalizes qualifying proprietary software development costs that are incurred during the application development stage. Capitalization of costs begins when two criteria are met: (1) the preliminary project stage is completed and (2) it is probable that the software will be completed and used for its intended function. Such costs are capitalized in the period incurred. Capitalization ceases and amortization begins when the software is substantially complete and ready for its intended use, including the completion of all significant testing. Costs related to preliminary project activities and post-implementation operating activities are expensed as incurred.

Leases

Contracts that have been determined to convey the right to use an identified asset are evaluated for classification as an operating or finance lease. For the Company’s operating leases, the Company records a lease liability based on the present value of the lease payments at lease inception, using the applicable incremental borrowing rate. The Company estimates the incremental borrowing rate by developing its own synthetic credit rating, corresponding yield curve, and the terms of each lease at the lease commencement date. The corresponding right-of-use asset is recorded based on the corresponding lease liability at lease inception, adjusted for payments made to the lessor at or before the commencement date, initial direct costs incurred and any tenant incentives allowed for under the lease. The Company does not include optional renewal terms or early termination provisions unless the Company is reasonably certain such options would be exercised at the inception of the lease. Operating lease right-of-use assets, current portion of operating lease liabilities, and operating lease liabilities, net of current portion are included on the Company’s condensed balance sheets.

The Company has elected the practical expedients that allows for the combination of lease components and non-lease components and to record short-term leases as lease expense on a straight-line basis on the condensed statements of operations. Variable lease payments are recorded as expense as they are incurred.

The Company has finance leases for vehicles and equipment, and the amounts of finance lease right-of-use assets and finance lease liabilities have been immaterial to date.

Convertible Senior Notes, net

Convertible debt instruments that may be settled in cash or other assets, or partially in cash, upon conversion, are separately accounted for as long-term debt and equity components (or conversion feature). The debt component represents the Company’s contractual obligation to pay principal and interest and the equity component represents the Company’s option to convert the debt security into equity of the Company or the equivalent amount of cash. Upon issuance, the Company allocated the debt component on the basis of the estimated fair value of a similar liability that does not have an associated convertible feature and the remaining

proceeds are allocated to the equity component. The bifurcation of the debt and equity components resulted in a debt discount for the aforementioned notes. The Company uses the effective interest method to amortize the debt discount to interest expense over the amortization period which is the expected life of the debt.

Capped Call Transactions

In June 2020 and March 2021, in connection with the issuance of its convertible senior notes, the Company entered into Capped Call Transactions (see Note 6). The Capped Call Transactions are expected generally to reduce the potential dilution to the holders of the Company’s common stock upon any conversion of the convertible senior notes and/or offset any cash payments the Company is required to make in excess of the principal amount of converted convertible senior notes, with such reduction and/or offset subject to a cap based on the cap price. The capped calls are classified in stockholders’ equity as a reduction to additional paid-in capital and are not subsequently remeasured as long as the conditions for equity classification continue to be met.

Debt Issuance Costs

Debt issuance costs are amortized to interest expense over the estimated life of the related debt based on the effective interest method. The Company presents debt issuance costs on the condensed balance sheets as a direct deduction from the associated debt. A portion of debt issuance costs incurred in connection with the convertible senior notes issued in June 2020 and March 2021 was related to the equity component and was recorded as a reduction to additional paid in capital and is not amortized to interest expense over the estimated life of the related debt.

Concentrations of Credit Risks

Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash and cash equivalents, restricted cash, accounts receivable, and investments. At times, such amount may exceed federally-insured limits. The Company reduces credit risk by placing its cash and cash equivalents, restricted cash, and investments with major financial institutions within the United States.

As of March 31, 2021 and December 31, 2020, there were no customers that represented 10% or more of the Company’s accounts receivable balance and there were no customers that individually exceeded 10% of the Company’s total revenue for each of the three months ended March 31, 2021 and 2020.

Recently Issued Accounting Pronouncements

In August 2020, the FASB issued ASU 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging-Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity, which simplifies accounting for convertible instruments. Under this ASU, the embedded conversion features will no longer be separated from the host contract for convertible instruments with conversion features that are not required to be accounted for as derivatives or that do not result in substantial premiums accounted for as paid-in capital. Consequently, a convertible debt instrument will be accounted for as a single liability measured at its amortized cost and a convertible preferred stock will be accounted for as a single equity instrument measured at its historical cost, as long as no other features require bifurcation and recognition as derivatives. ASU 2020-06 removes certain settlement conditions that are required for equity contracts to qualify for the derivative scope exception and it also simplifies the diluted earnings per share calculation in certain areas. The ASU will be effective for annual reporting periods beginning after December 15, 2021 and early adoption is permitted. The Company is currently evaluating the impact of this standard on its financial statements. It is expected that upon adoption, the Company’s Convertible Senior Notes, as discussed in Note 7, will no longer be bifurcated into an equity and a debt component, but rather accounted for as a single liability.