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Organization and Significant Accounting Policies | 12 Months Ended
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Dec. 31, 2023
Accounting Policies [Abstract] |
Organization and Significant Accounting Policies | 1. Organization and Significant Accounting Policies The Company Alphatec Holdings, Inc. (the “Company”), through its wholly owned subsidiaries, Alphatec Spine, Inc. (“Alphatec Spine”), SafeOp Surgical, Inc. (“SafeOp”), and EOS imaging S.A.S. (“EOS”), is a medical technology company focused on the design, development, and advancement of technology for the better surgical treatment of spinal disorders. The Company, headquartered in Carlsbad, California, markets its products in the United States ("U.S.") and internationally via a network of independent sales agents and direct sales representatives. Basis of Presentation and Principles of Consolidation The consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America ("U.S. GAAP") and include the accounts of the Company and its wholly owned subsidiaries. The Company translates the financial statements of its foreign subsidiaries using end-of-period exchange rates for assets and liabilities and average exchange rates during each reporting period for results of operations. All intercompany balances and transactions have been eliminated in consolidation. The Company operates in one reportable business segment. Prior-year Adjustment Subsequent to the issuance of the Company’s consolidated financial statements as of and for the year ended December 31, 2022, the Company identified that a deferred tax liability and additional goodwill related to the acquisition of EOS should have been recorded at the time of the acquisition. The Company corrected the errors in the accompanying consolidated financial statements as of the earliest year presented and has concluded that the correction of these errors is not material to the previously issued financial statements. The correction to the accompanying consolidated balance sheets, consolidated statements of operations, consolidated statements of comprehensive loss, consolidated statements of stockholders' equity, and consolidated statements of cash flows are as follows (in thousands):
|  |  |  |  |  |  |  |  | At December 31, 2022 |
Consolidated Balance Sheets |  |  |  |  |  |  |  |  | As Reported |  | Adjustment |  | As Corrected |
Goodwill |  |  |  |  |  |  |  |  | $ | 39,775 |  |  | 7,592 |  | $ | 47,367 |
Total assets |  |  |  |  |  |  |  |  | $ | 513,376 |  |  | 7,592 |  | $ | 520,968 |
Other long-term liabilities |  |  |  |  |  |  |  |  | $ | 11,543 |  |  | 5,546 |  | $ | 17,089 |
Accumulated other comprehensive loss |  |  |  |  |  |  |  |  | $ | (10,690 | ) |  | (104 | ) | $ | (10,794 | )
Accumulated deficit |  |  |  |  |  |  |  |  | $ | (934,474 | ) |  | 2,150 |  | $ | (932,324 | )
Total stockholders' deficit |  |  |  |  |  |  |  |  | $ | (36,713 | ) |  | 2,046 |  | $ | (34,667 | )
Total liabilities and stockholders' deficit |  |  |  |  |  |  |  |  | $ | 513,376 |  |  | 7,592 |  | $ | 520,968 |
|  | Year Ended December 31, 2022 |  |  | Year Ended December 31, 2021 |
Consolidated Statements of Operations |  | As Reported |  | Adjustment |  | As Corrected |  |  | As Reported |  | Adjustment |  | As Corrected |
Income tax provision (benefit) |  | $ | 140 |  |  | (856 | ) | $ | (716 | ) |  | $ | 164 |  |  | (1,294 | ) | $ | (1,130 | )
Net loss |  | $ | (152,149 | ) |  | 856 |  | $ | (151,293 | ) |  | $ | (144,326 | ) |  | 1,294 |  | $ | (143,032 | )
Net loss per share, basic and diluted |  | $ | (1.47 | ) | $ | 0.01 |  | $ | (1.46 | ) |  | $ | (1.50 | ) | $ | 0.01 |  | $ | (1.49 | )
|  | Year Ended December 31, 2022 |  |  | Year Ended December 31, 2021 |
Consolidated Statements of Comprehensive Loss |  | As Reported |  | Adjustment |  | As Corrected |  |  | As Reported |  | Adjustment |  | As Corrected |
Net loss |  | $ | (152,149 | ) |  | 856 |  | $ | (151,293 | ) |  | $ | (144,326 | ) |  | 1,294 |  | $ | (143,032 | )
Foreign currency translation adjustments |  | $ | (4,696 | ) |  | (62 | ) | $ | (4,758 | ) |  | $ | (7,198 | ) |  | (42 | ) | $ | (7,240 | )
Comprehensive loss |  | $ | (156,845 | ) |  | 794 |  | $ | (156,051 | ) |  | $ | (151,524 | ) |  | 1,252 |  | $ | (150,272 | )
|  | At December 31, 2022 |  |  | At December 31, 2021 |
Consolidated Statements of Stockholders' (Deficit) Equity |  | As Reported |  | Adjustment |  | As Corrected |  |  | As Reported |  | Adjustment |  | As Corrected |
Foreign currency translation adjustments |  | $ | (4,696 | ) |  | (62 | ) | $ | (4,758 | ) |  | $ | (7,198 | ) |  | (42 | ) | $ | (7,240 | )
Net loss |  | $ | (152,149 | ) |  | 856 |  | $ | (151,293 | ) |  | $ | (144,326 | ) |  | 1,294 |  | $ | (143,032 | )
Accumulated other comprehensive loss |  | $ | (10,690 | ) |  | (104 | ) | $ | (10,794 | ) |  | $ | (5,994 | ) |  | (42 | ) | $ | (6,036 | )
Accumulated deficit |  | $ | (934,474 | ) |  | 2,150 |  | $ | (932,324 | ) |  | $ | (782,325 | ) |  | 1,294 |  | $ | (781,031 | )
Total stockholders' (deficit) equity |  | $ | (36,713 | ) |  | 2,046 |  | $ | (34,667 | ) |  | $ | 79,422 |  |  | 1,252 |  | $ | 80,674 |
|  | Year Ended December 31, 2022 |  |  | Year Ended December 31, 2021 |
Consolidated Statements of Cash Flows |  | As Reported |  | Adjustment |  | As Corrected |  |  | As Reported |  | Adjustment |  | As Corrected |
Net loss |  | $ | (152,149 | ) |  | 856 |  | $ | (151,293 | ) |  | $ | (144,326 | ) |  | 1,294 |  | $ | (143,032 | )
Other long-term liabilities |  | $ | (2,342 | ) |  | (847 | ) | $ | (3,189 | ) |  | $ | 4,852 |  |  | (1,179 | ) | $ | 3,673 |
Net cash used for operating activities |  | $ | (75,143 | ) |  | 9 |  | $ | (75,134 | ) |  | $ | (73,432 | ) |  | 115 |  | $ | (73,317 | )
Effect of exchange rate changes on cash |  | $ | (357 | ) |  | (9 | ) | $ | (366 | ) |  | $ | (1,289 | ) |  | (115 | ) | $ | (1,404 | )
Reclassification Certain financial statement line items in the consolidated financial statements for the year ended December 31, 2022 have been disaggregated to conform to the current year’s presentation. 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, the disclosure of contingent assets and liabilities, and the reported amounts of revenues and expenses. Actual results could differ from those estimates. Significant items subject to such estimates and assumptions include the useful lives of property and equipment, goodwill, intangible assets, allowances for doubtful accounts, deferred tax assets, inventory, stock-based compensation, revenues, income tax uncertainties, and other contingencies. Concentrations of Credit Risk and Significant Customers Financial instruments, which potentially subject the Company to concentrations of credit risk, consist primarily of cash, cash equivalents, and accounts receivable. The Company limits its exposure to credit loss by depositing its cash and investments with established financial institutions. Although the Company deposits its cash with multiple financial institutions, its deposits, at times, may exceed federally insured limits. The Company’s customers are primarily hospitals and surgical centers. No one single customer represented greater than 10 percent of consolidated revenues and accounts receivable for the years presented. Credit to customers is granted based on an analysis of the customers’ credit worthiness. Credit losses have not been significant. Cash and Cash Equivalents The company considers all highly liquid investments that are readily convertible into cash and have an original maturity of three months or less at the time of purchase to be cash equivalents. Accounts Receivable, net Accounts receivable are presented net of allowance for doubtful accounts. The Company makes judgments as to its ability to collect outstanding receivables and provides allowances for a portion of receivables when collection becomes doubtful. Provisions are made based upon a specific review of all significant outstanding invoices. In determining the provision for invoices not specifically reviewed, the Company analyzes historical collection experience. If the historical data used to calculate the allowance provided for doubtful accounts does not reflect the Company’s future ability to collect outstanding receivables or if the financial condition of customers were to deteriorate, resulting in impairment of their ability to make payments, an increase in the provision for doubtful accounts may be required. The Company’s accounts receivable generally have net 30-day payment terms. The Company generally does not allow returns of products that have been delivered. The Company offers standard quality assurance warranty on its products. The Company had no material bad debt expense during the years presented. Excess and Obsolete Inventory Most of the Company’s inventory is comprised of finished goods, which is primarily produced by third-party suppliers. Specialized implants, fixation products, and biologics are determined by utilizing a standard cost method that includes capitalized variances which approximates the weighted average cost. Imaging equipment and related parts are valued at weighted average cost. Inventories are stated at the lower of cost or net realizable value. The Company reviews the components of its inventory on a periodic basis for excess and obsolescence and adjusts inventory to its net realizable value as necessary. The Company records a lower of cost or net realizable value (“LCNRV”) inventory reserve for estimated excess and obsolete inventory based upon its expected use of inventory on hand. The Company’s inventory, which consists primarily of specialized implants, fixation products, and biologics is at risk of obsolescence due to the need to maintain substantial levels of inventory. In order to market its products effectively and meet the demands of interoperative product placement, the Company maintains and provides surgeons and hospitals with a variety of inventory products and sizes. For each surgery, fewer than all components will be consumed. The need to maintain and provide a wide variety of inventory causes inventory to be held that is not likely to be used. The Company’s estimates and assumptions for excess and obsolete inventory are reviewed and updated on a quarterly basis. The estimates and assumptions are determined primarily based on current usage of inventory and the age of inventory quantities on hand. Additionally, the Company considers recent sales experience to develop assumptions about future demand for its products, while considering product life cycles and new product launches. Increases in the LCNRV reserve for excess and obsolete inventory result in a corresponding charge to cost of sales. For the years ended December 31, 2023, 2022 and 2021, the Company recorded LCNRV charges for excess and obsolete inventory of $13.6 million, $9.8 million and $11.1 million, respectively, net of inventory sold of $0.2 million, $1.5 million and $2.5 million, respectively. For the years ended December 31, 2023, 2022 and 2021, the Company recorded a reduction of reserve for inventory that was disposed of $12.9 million, $8.2 million and $2.1 million, respectively. Property and Equipment, net Property and equipment are stated at cost, net of accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the related assets, generally ranging from three to seven years. Leasehold improvements and assets acquired under financing leases are amortized over the shorter of their useful lives or the remaining terms of the related leases. Operating Lease The Company determines whether a contract is a lease or contains a lease at inception by assessing whether there is an identified asset and whether the contract conveys the right to control the use of the identified asset in exchange for consideration over a period of time. If both criteria are met, the Company determines the initial classification and measurement of its right-of-use (“ROU”) asset and lease liability at the lease commencement date and thereafter, if modified. The Company recognizes a ROU asset and lease liability for its operating leases with lease terms greater than 12 months. The lease term includes any renewal options and termination options that the Company is reasonably assured to exercise. ROU assets and lease liabilities are based on the present value of lease payments over the lease term. The present value of operating lease payments is determined by using the incremental borrowing rate of interest that the Company would borrow on a collateralized basis for an amount equal to the lease payments in a similar economic environment. Rent expense for operating leases is recognized on a straight-line basis over the reasonably assured lease term based on the total lease payments and is included in cost of sales, research and development, and sales, general and administrative expenses in the consolidated statements of operations. The Company aggregates all lease and non-lease components for each class of underlying assets into a single lease component and variable charges for common area maintenance and other variable costs are recognized as expense as incurred. Total variable costs associated with leases were immaterial for all years presented. The Company had an immaterial amount of financing leases as of December 31, 2023 and 2022, which is included in property and equipment, net, accrued expenses and other current liabilities, and other long-term liabilities on the consolidated balance sheets. Valuation of Goodwill Goodwill represents the excess of the cost over the fair value of net assets acquired from the Company’s business combinations. The determination of the value of goodwill and intangible assets arising from business combinations and asset acquisitions requires extensive use of accounting estimates and judgments to allocate the purchase price to the fair value of the net tangible and intangible assets acquired. Goodwill is assessed for impairment using fair value measurement techniques on an annual basis or more frequently if facts and circumstance warrant such a review. Goodwill is considered to be impaired if the Company determines that the carrying value of the reporting unit exceeds its respective fair value. The Company’s annual evaluation for impairment of goodwill consists of one reporting unit. The Company completed its most recent annual evaluation for impairment of goodwill as of October 1, 2023 and determined that no impairment existed. In addition, no indicators of impairment were noted through December 31, 2023, and consequently no impairment charge was recorded during the years ended December 31, 2023, 2022 and 2021. Valuation of Intangible Assets Intangible assets are comprised primarily of purchased technology, customer relationships, trade name, trademarks, and in-process research and development. The Company makes significant judgments in relation to the valuation of intangible assets resulting from business combinations and asset acquisitions. Intangible assets are generally amortized on a straight-line basis over their estimated useful lives of 2 to 12 years. The Company bases the useful lives and related amortization expense on the period of time it estimates the assets will generate net sales or otherwise be used. The Company also periodically reviews the lives assigned to its intangible assets to ensure that its initial estimates do not exceed any revised estimated periods from which the Company expects to realize cash flows. If a change were to occur in any of the above-mentioned factors or estimates, the likelihood of a material change in the Company’s reported results would increase. The Company evaluates its intangible assets with finite lives for indications of impairment whenever events or changes in circumstances indicate that the carrying value may not be recoverable. Factors that could trigger an impairment review include significant under-performance relative to expected historical or projected future operating results, significant changes in the manner of the Company’s use of the acquired assets or the strategy for its overall business or significant negative industry or economic trends. If this evaluation indicates that the value of the intangible asset may be impaired, the Company makes an assessment of the recoverability of the net carrying value of the asset over its remaining useful life. If this assessment indicates that the intangible asset is not recoverable, based on the estimated undiscounted future cash flows of the asset over the remaining amortization period, the Company reduces the net carrying value of the related intangible asset to fair value and may adjust the remaining amortization period. Significant judgment is required in the forecasts of future operating results that are used in the discounted cash flow valuation models. It is possible that plans may change and estimates used may prove to be inaccurate. If actual results, or the plans and estimates used in future impairment analyses, are lower than the original estimates used to assess the recoverability of these assets, the Company could incur additional impairment charges. There were no impairment charges during the years ended December 31, 2023, 2022 or 2021. In-process research and development ("IPR&D") and software in development have indefinite lives and are not amortized until the related products reach full commercial launch or when the projects are complete and their assets are ready for their intended use. Indefinite-lived intangible assets are considered to be impaired if the products do not reach commercial launch, if the project is not completed or not completed in a timely manner, or if the related products or projects are no longer technologically feasible. Impairment related to IPR&D and software in development is calculated as the excess of the asset's carrying value over its fair value. There were no impairment charges during the years ended December 31, 2023, 2022 or 2021. Impairment of Long-Lived Assets The Company assesses potential impairment to its long-lived assets when there is evidence that events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. An impairment loss is recognized when estimated future undiscounted cash flows related to the asset are less than its carrying amount. Any required impairment loss is measured as the amount by which the carrying amount of a long-lived asset exceeds its fair value and is recorded as a reduction in the carrying value of the related asset and a charge to operating results. There were no material impairment charges during the years ended December 31, 2023, 2022 or 2021. Warrants to Purchase Common Stock Warrants are accounted for in accordance with the applicable accounting guidance as either derivative liabilities or as equity instruments depending on the specific terms of the agreements. All warrants qualify for classification within stockholders' equity. Fair Value Measurements The carrying amount of financial instruments consisting of cash and cash equivalents, accounts receivable, prepaid expenses and other current assets, accounts payable, accrued expenses, and short-term debt included in the Company’s consolidated financial statements are reasonable estimates of fair value due to their short maturities. Authoritative guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: Level 1: Quoted prices in active markets for identical assets or liabilities. Level 2: Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active; or other inputs that can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Revenue Recognition The Company recognizes revenue from product sales in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Revenue from Contracts with Customers (“Topic 606”). This standard applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaboration arrangements, and financial instruments. Under Topic 606, an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of Topic 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. Sales are derived primarily from the sale of spinal implant products, imaging equipment, and related services to hospitals and medical centers through direct sales representatives and independent sales agents. Revenue is recognized when obligations under the terms of a contract with customers are satisfied, which occurs with the transfer of control of products to customers, either upon shipment of the product or delivery of the product to the customer depending on the shipping terms, or when the products are used in a surgical procedure (implanted in a patient). Revenue from the sale of imaging equipment is recognized as each distinct performance obligation is fulfilled and control transfers to the customer, beginning with shipment or delivery, depending on the terms. Revenue from other distinct performance obligations, such as maintenance on imaging equipment and other imaging related services, is recognized in the period the service is performed, and makes up less than 10% of the Company’s total revenue. Revenue is measured based on the amount of consideration expected to be received in exchange for the transfer of the goods or services specified in the contract with each customer. In certain cases, the Company does offer the ability for customers to lease its imaging equipment primarily on a non-sales type basis, but such arrangements are immaterial to total revenue in the years presented. The Company generally does not allow returns of products that have been delivered. Costs incurred by the Company associated with sales contracts with customers are deferred over the performance obligation period and recognized in the same period as the related revenue, except for contracts that complete within one year or less, in which case the associated costs are expensed as incurred. Payment terms for sales to customers may vary but are commensurate with the general business practices in the country of sale. To the extent that the transaction price includes variable consideration, such as discounts, rebates, and customer payment penalties, the Company estimates the amount of variable consideration that should be included in the transaction price utilizing either the expected value method or the most likely amount method depending on the nature of the variable consideration. Variable consideration is included in the transaction price if, in the Company’s judgment, it is probable that a significant future reversal of cumulative revenue under the contract will not occur. Estimates of variable consideration and determination of whether to include estimated amounts in the transaction price are based largely on an assessment of the Company’s anticipated performance and all information that is reasonably available, including historical, current, and forecasted information. The Company records a contract asset when one or more performance obligations have been completed and revenue has been recognized, but the customer's payment is contingent on the satisfaction of additional performance obligations. The Company records a contract liability, or deferred revenue, when it has an obligation to provide a product or service to the customer and payment is received in advance of its performance. When the Company sells a product or service with a future performance obligation, revenue is deferred on the unfulfilled performance obligation and recognized over the related performance period. Generally, the Company does not have observable evidence of the standalone selling price related to its future service obligations; therefore, the Company estimates the selling price using an expected cost plus a margin approach. The transaction price is allocated using the relative standalone selling price method. The use of alternative estimates could result in a different amount of revenue deferral. Research and Development Expenses Research and development costs are expensed as incurred. Research and development expenses consist of costs associated with the design, development, testing, and enhancement of the Company's products. Research and development expenses also include salaries and related employee benefits, research-related overhead expenses, fees paid to external service providers and development consultants in the form of both cash and equity. Transaction-related Expenses Transaction-related costs are expensed as incurred. Transaction-related expenses consist of certain costs incurred related primarily to the acquisition and integration of Valence, as defined below, and EOS. Product Shipment Cost Product shipment costs for surgical sets are included in sales, general and administrative expenses in the accompanying consolidated statements of operations. Product shipment costs totaled $17.3 million, $14.8 million and $8.3 million for the years ended December 31, 2023, 2022 and 2021 respectively. Stock-Based Compensation Stock-based compensation expense for equity-classified awards, principally related to restricted stock units ("RSUs") and performance restricted stock units ("PRSUs") is measured at the grant date based on the estimated fair value of the award. The fair value of equity instruments that are expected to vest is recognized and amortized over the requisite service period. The Company has granted awards with up to four year graded or cliff vesting terms. No exercise price or other monetary payment is required for receipt of the shares issued in settlement of the respective award; instead, consideration is furnished in the form of the participant’s service. The fair value of RSUs including PRSUs with pre-defined performance criteria is based on the stock price on the date of grant. Stock-based compensation recorded in the Company’s consolidated statements of operations is based on awards expected to ultimately vest and has been reduced for estimated forfeitures. The Company’s estimated forfeiture rates may differ from its actual forfeitures. The Company considers its historical experience of pre-vesting forfeitures on awards by each homogenous group of employees as the basis to arrive at its estimated annual pre-vesting forfeiture rates. The Company estimates the fair value of stock options issued under the Company’s equity incentive plans and shares issued to employees under the Company’s employee stock purchase plan (“ESPP”) using a Black-Scholes option-pricing model on the date of grant. The Black-Scholes option-pricing model incorporates various assumptions including expected volatility, expected term and risk-free interest rates. The expected volatility is based on the historical volatility of the Company’s common stock over the most recent period commensurate with the estimated expected term of the Company’s stock options and ESPP offering period which is derived from historical experience. The risk-free interest rate for periods within the contractual life of the option is based on the U.S. Treasury yield in effect at the time of grant. The Company has never declared or paid dividends and has no plans to do so in the foreseeable future. Awards to non-employees are accounted for under the same stock-based compensation provisions as employees, which require that the fair value of these instruments be recognized as an expense when earned. For Development Service Agreements, where the future payments for product and/or intellectual property rights may be paid in either cash or restricted shares of our common stock at the election of the developer, we estimate the fair value of those awards similar to a stock option, using a Black-Scholes option-pricing model on the date of grant. For Development Service Agreements where the future payments for product and/or intellectual property rights will be paid in restricted shares of our common stock, the fair value is based on the stock price on the date of grant. The stock-based compensation expense is recognized as earned once the award is deemed probable of achieving the pre-defined performance criteria. The stock-based compensation expense is included in cost of sales or research and development expense on the consolidated statements of operations commensurate with the nature of the services performed. Income Taxes The Company accounts for income taxes in accordance with provisions which set forth an asset and liability approach that requires the recognition of deferred tax assets and deferred tax liabilities for the expected future tax consequences of temporary differences between the carrying amounts and the tax bases of assets and liabilities. Valuation allowances are established when necessary to reduce deferred tax assets to the amount expected to be realized. In making such determination, a review of all available positive and negative evidence must be considered, including scheduled reversal of deferred tax liabilities, projected future taxable income, tax planning strategies, and recent financial performance. The Company recognizes interest and penalties related to uncertain tax positions as a component of the income tax provision. Net Loss per Share Basic net loss per share is calculated by dividing the net loss available to common stockholders by the weighted-average number of common shares outstanding for the year. If applicable, diluted net loss per share attributable to common stockholders is calculated by dividing net loss available to common stockholders by the diluted weighted-average number of common shares outstanding for the year determined using the treasury-stock method and the if-converted method for convertible debt. For purposes of this calculation, common stock subject to repurchase by the Company, common stock issuable upon conversion or exercise of convertible notes, preferred shares, options, and warrants are considered to be common stock equivalents and are only included in the calculation of diluted earnings per share when their effect is dilutive. Due to the Company’s net loss position, the effect of including common stock equivalents in the earnings per share calculation is anti-dilutive, and therefore not included. The following table sets forth the computation of basic and diluted loss per share (in thousands, except per share data):
|  | Year Ended December 31, |
|  | 2023 |  |  | 2022 |  |  | 2021 |
Numerator: |  |  |  |  |  |  |  |  |
Net loss |  | $ | (186,638 | ) |  | $ | (151,293 | ) |  | $ | (143,032 | )
Denominator: |  |  |  |  |  |  |  |  |
Weighted average common shares outstanding |  |  | 121,242 |  |  |  | 103,373 |  |  |  | 96,197 |
Net loss per share, basic and diluted |  | $ | (1.54 | ) |  | $ | (1.46 | ) |  | $ | (1.49 | )
The following potentially dilutive shares of common stock were excluded from the calculation of diluted net loss per share because their effect would have been anti-dilutive for the years presented (in thousands):
|  | Year Ended December 31, |
|  | 2023 |  |  | 2022 |  |  | 2021 |
Series A convertible preferred stock |  |  | — |  |  |  | — |  |  |  | 29 |
Options to purchase common stock and employee stock purchase plan |  |  | 2,555 |  |  |  | 2,991 |  |  |  | 3,416 |
Unvested restricted stock units |  |  | 7,713 |  |  |  | 8,533 |  |  |  | 8,703 |
Warrants to purchase common stock |  |  | 8,219 |  |  |  | 15,491 |  |  |  | 20,184 |
Senior convertible notes |  |  | 17,246 |  |  |  | 17,246 |  |  |  | 17,246 |
|  |  | 35,733 |  |  |  | 44,261 |  |  |  | 49,578 |
Recently Adopted and Issued Accounting Pronouncements In August 2021, the FASB issued Accounting Standards Update ("ASU") No. 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers. The guidance requires application of Topic 606, Revenue from Contracts with Customers to recognize and measure contract assets and contract liabilities acquired in a business combination. ASU No. 2021-08 adds an exception to the general recognition and measurement principle in Topic 805 where assets acquired and liabilities assumed in a business combination, including contract assets and contract liabilities arising from contracts with customers, are measured at fair value on the acquisition date. Under the new guidance, the acquirer will recognize acquired contract assets and contract liabilities as if the acquirer had originated the contract. The standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2022, with early adoption permitted. The Company adopted ASU No. 2021-08 as of January 1, 2023, on a prospective basis. The adoption of ASU No. 2021-08 did not have a material impact on the Company's consolidated financial statements and related disclosures. In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvement to Income Tax Disclosures to enhance the transparency of income tax disclosures. The guidance in ASU No. 2023-09 allows for a prospective method of transition, with the option to apply the standard retrospectively. The standard is effective for fiscal years beginning after December 15, 2024, with early adoption permitted. The Company does not intend to early adopt the standard and is in the process of assessing the impact on its consolidated financial statements and related disclosures. In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures that expands disclosure requirements for reportable segments, primarily through enhanced disclosure of significant segment expenses. The guidance in ASU No. 2023-07 allows for a retrospective method of transition. The standard is effective for fiscal years beginning after December 15, 2023 and interim periods in fiscal years beginning after December 15, 2024, with early adoption permitted. The Company does not intend to early adopt the standard and is in the process of assessing the impact on its consolidated financial statements and related disclosures. In October 2023, the FASB issued ASU No. 2023-06, Disclosure Improvements - Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative. The guidance amends the ASC to incorporate certain disclosure requirements from SEC Release No. 33-10532 Disclosure Update and Simplification issued in 2018. The effective date for each amendment will be the date on which the Securities and Exchange Commission's removal of that related disclosure from Regulation S-X or Regulation S-K becomes effective, with early adoption prohibited. ASU No. 2023-06 is not expected to have a material impact on the Company's financial statements.

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- Definition The entire disclosure for the organization, consolidation and basis of presentation of financial statements disclosure, and significant accounting policies of the reporting entity. May be provided in more than one note to the financial statements, as long as users are provided with an understanding of (1) the significant judgments and assumptions made by an enterprise in determining whether it must consolidate a VIE and/or disclose information about its involvement with a VIE, (2) the nature of restrictions on a consolidated VIE's assets reported by an enterprise in its statement of financial position, including the carrying amounts of such assets, (3) the nature of, and changes in, the risks associated with an enterprise's involvement with the VIE, and (4) how an enterprise's involvement with the VIE affects the enterprise's financial position, financial performance, and cash flows. Describes procedure if disclosures are provided in more than one note to the financial statements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 235 -Name Accounting Standards Codification -Publisher FASB -URI https://asc.fasb.org//235/tableOfContent Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 275 -Name Accounting Standards Codification -Publisher FASB -URI https://asc.fasb.org//275/tableOfContent Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 810 -Name Accounting Standards Codification -Publisher FASB -URI https://asc.fasb.org//810/tableOfContent Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 205 -Name Accounting Standards Codification -Publisher FASB -URI https://asc.fasb.org//205/tableOfContent + Details
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