Summary of Significant Accounting Policies | Summary of Significant Accounting Policies Basis of Presentation The financial statements have been prepared in conformity with generally accepted accounting principles in the United States, or GAAP, as defined by the Financial Accounting Standards Board, or the FASB. Use of Estimates The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the amounts and disclosures reported in the financial statements. The Company uses significant judgment when making estimates related to the provision for excess and obsolete inventories. The Company bases its estimates on historical experience and on various other assumptions that are believed to be 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. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions. Segment and Geographical Information The Company operates and manages its business as one reportable and operating segment. The Company’s chief executive officer, who is the chief operating decision maker, reviews financial information on an aggregate basis for purposes of allocating resources and evaluating financial performance. All of the Company’s long-lived assets, comprised of property and equipment, are based in the United States. All of the Company’s revenue, with the exception of less than $0.1 million, was in the United States for the year ended December 31, 2023, based on the shipping location of the external customer. All of the Company’s revenue was in the United States for the year ended December 31, 2022, based on the shipping location of the external customer. Revenue Recognition The Company derives most of its revenue from sales of RNS Systems to hospital facilities (typically comprehensive epilepsy centers, or Level 4 CECs) that implant its products. Beginning in the fourth quarter of 2022, the Company also derives revenue from sales of DIXI Medical products, primarily to its current customer base. Beginning in the fourth quarter of 2023, the Company also derives revenue from services provided to Rapport Therapeutics, or Rapport. The Company recognizes revenue in accordance with Accounting Standards Codification, or ASC, 606, “Revenue from Contracts with Customers.” Under ASC 606, revenue is recognized when a customer obtains control of promised goods or services, in an amount that reflects the consideration which 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 ASC 606, the Company 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. At contract inception, the Company assesses the products or services promised within each contract and determines those that are performance obligations. The Company’s contracts with customers for the RNS System often include a promise to transfer products, as well as an implied promise to provide a service to the customer, which is access to the Company’s Patient Data Management System, or PDMS, and nSight Platform. The Company has concluded that the RNS System and its related products represent a single performance obligation, as the customer cannot benefit from the products individually, and that access to the PDMS and nSight Platform represent separate performance obligations, as the clinicians can utilize them with other components of the RNS System that are readily available. The Company determines the transaction price based on the amount it expects to be entitled to in exchange for transferring the promised product or service to the customer, which is based on the invoiced price for the products or services. All prices are at fixed amounts per the sales agreement with the customer and there are no discounts, rebates or other price concessions. When a contract contains multiple performance obligations, the Company allocates the transaction price to each performance obligation based on its relative standalone selling price. Standalone selling prices are based on observable prices at which the Company separately sells its products or services. If a standalone selling price is not directly observable, the Company estimates the standalone selling price considering market data, cost, gross margin, and other available information. The Company typically delivers its RNS System and related products to a hospital on the date of the scheduled procedure. There is no commitment or contract until the delivery of the product and the procedure may be canceled at any time. Once the device has been implanted in or otherwise provided to a patient, the customer is considered to have accepted the delivery (i.e., has approved the contract) and both parties are committed to perform their respective obligations. Assuming all other revenue recognition criteria are met, the Company recognizes revenue from the sale of its RNS System and related products at a point in time when the procedure is completed and the device is implanted in a patient. The Company also ships the RNS System and related products to customers who place orders ahead of scheduled procedures. Such orders or contracts generally include a promise to transfer products only. As such, the Company recognizes revenue from these orders or contracts at a point in time when the customer obtains control of the products. The Company recognizes service revenue related to the PDMS and the nSight Platform on a ratable basis over the period in which the Company expects to provide access to clinicians. The Company has concluded that such service revenue is immaterial. The Company’s contracts with customers for DIXI Medical products generally include a promise to transfer products only. As such, the Company recognizes revenue from the sale of DIXI Medical products at a point in time when the customer obtains control of the products. The Company recognizes revenue under its contract with Rapport to provide biomarker monitoring and data analysis services. Revenue from biomarker monitoring is recognized ratably over the two-year contractual support period, as the benefits provided by the Company’s performance are simultaneously consumed by the customer. Revenue related to data analysis is recognized upon completion of the services. The Company’s contract with Rapport commenced during the fourth quarter of 2023, and the related revenue recognized as of December 31, 2023 is immaterial. The Company recognizes revenue for arrangements where it has satisfied its performance obligations but has not issued invoices. These amounts are recorded as unbilled receivables, which are included in accounts receivable on the balance sheet, as the Company has an unconditional right to payment at the end of the applicable period. Payment terms are typically 30 days from the fulfillment of the orders and fall within the one-year guidance for the practical expedient which allows the Company to forgo adjustment of the promised amount of consideration for the effects of a significant financing component. Sales taxes that are collected from customers and remitted to governmental authorities are accounted for on a net basis and therefore are excluded from net sales, however, most of the Company’s sales are tax exempt. The Company believes that collection is probable as it has no history of uncollectible accounts and the customers are large, creditworthy institutions. As allowed under the practical expedient, the Company does not disclose the value of unsatisfied performance obligations for contracts with an original expected length of one year or less. Costs associated with product sales include commissions, where the Company applies the practical expedient and recognizes commissions as expense when incurred because the expense is incurred over a period of time of less than one year. Commissions are reported in selling, general and administrative expense in the statements of operations and comprehensive loss. The Company’s contract balances were accounts receivable of $12.3 million and $7.5 million as of December 31, 2023, and December 31, 2022, respectively. The Company’s contract liabilities consist of deferred revenue for remaining performance obligations by the Company to transfer goods or services for which the Company has received consideration. The Company’s deferred revenue balance was $1.1 million as of December 31, 2023, which is expected to be recognized as revenue in 2024. The Company had no deferred revenue as of December 31, 2022. Fair Value of Financial Instruments Carrying amounts of certain of the Company’s financial instruments, including cash equivalents, accounts receivable, accounts payable and accrued liabilities, approximate fair value because of the short-term nature of these instruments. The Company has a short-term investment in a fixed income mutual fund, which is classified as equity security and carried at fair value based on quoted market prices. Changes in the fair value of the short-term investment are recorded in income or loss. The Company believes that its borrowings bear interest at the prevailing market rates for instruments with similar characteristics; accordingly, the carrying value of this instrument approximates its fair value. The Company determines the fair value of financial and non-financial assets and liabilities using the fair value hierarchy which establishes three levels of inputs that may be used to measure fair value (see Note 3). Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents. Cash equivalents that are available-for-sale investments are recorded at fair value, based on quoted market prices. As of December 31, 2023 and December 31, 2022, the Company’s cash equivalents are entirely comprised of investments in money market funds. Restricted Cash Restricted cash is comprised of cash that is restricted as to withdrawal or use under the terms of certain contractual agreements. Restricted cash for the years ended December 31, 2023 and December 31, 2022 consists of collateral for the letter of credit issued during the year in connection with the Company’s facility lease (see Note 5). Concentration of Credit Risk, and Other Risks and Uncertainties Financial instruments that potentially subject the Company to credit risk consist of cash and cash equivalents, short-term investments and accounts receivable to the extent of the amounts recorded on the balance sheets. The Company’s cash is invested in major financial institutions in the United States. Deposits in these financial institutions may exceed federally insured limits, and the Company is exposed to credit risk on deposits in the event of default of the financial institutions to the extent account balances exceed the amount insured by the Federal Deposit Insurance Corporation. The Company’s cash equivalents are invested in money market funds. The Company’s accounts receivable are due from a variety of health care organizations in the United States. For the years ended December 31, 2023 and December 31, 2022, there were no customers that represented 10% or more of revenue. As of December 31, 2023 and December 31, 2022, no customer represented 10% or more of the Company’s accounts receivable. The Company is subject to certain risks, including that its devices may not be approved or cleared or continue to be approved or cleared for marketing by governmental authorities or be successfully marketed for expanded indications. There can be no assurance that the Company’s products will achieve widespread adoption in the marketplace, nor can there be any assurance that existing devices or any future devices can be developed or manufactured at an acceptable cost and speed and with appropriate performance characteristics. The Company is also subject to risks common to companies in the medical device industry, including, but not limited to, new technological innovations, dependence on healthcare providers to prescribe initial implants and replacements, dependence upon third-party payors to provide adequate coverage and reimbursement, dependence on key personnel, single-source suppliers and vendors in connection with the manufacture of its products, concentration of comprehensive epilepsy centers, or CECs, and epileptologists, obtaining, maintaining, protecting, enforcing, and defending intellectual property rights and proprietary technology, product liability claims, legal proceedings, and compliance with government regulations. The Company’s medical devices require approvals or clearances from the U.S. Food and Drug Administration, or the FDA, or international regulatory agencies. In addition, in order to continue the Company’s operations, compliance with various federal and state laws is required. If approvals or clearances were withdrawn by the FDA for the Company’s current products or if such approvals or clearances were denied or delayed for future products, product updates, or expanded indications for use, it would have a material adverse impact on the Company. Accounts Receivable Accounts receivable are recorded at the invoiced amount and do not bear interest. The Company makes estimates on the collectability of customer accounts based primarily on analysis of historical trends and experience, the age of the receivable and changes in customers’ financial condition. The Company uses its judgment, based on the best available facts and circumstances, and records an allowance against amounts due to reduce the receivable to the amount that is expected to be collected. The Company determined that no allowance was required as of December 31, 2023 and December 31, 2022. To date, the Company has not experienced any material credit-related losses. Inventories Inventories are valued at the lower of cost or net realizable value. Cost is determined using the first-in, first-out method for all inventories. Net realizable value is determined as the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal and transportation. The Company regularly reviews inventory quantities in consideration of actual loss experiences, projected future demand, and remaining shelf life to record a provision for excess and obsolete inventory when appropriate. The Company’s policy is to write down inventory that has become obsolete, inventory that has a cost basis in excess of its expected lower of cost or net realizable value, and inventory in excess of expected requirements. The estimate of excess quantities is judgmental and primarily dependent on the Company’s estimates of future demand for a particular product. If the estimate of future demand is too high, the Company may have to increase the reserve for excess inventory for that product and record a charge to the cost of goods sold. Inventory write-downs were $0.2 million and $0.2 million for the years ended December 31, 2023 and December 31, 2022, respectively. Property and Equipment, net Property and equipment, net is stated at cost less accumulated depreciation. Depreciation is calculated using the straight-line method over the estimated useful lives of the assets, generally three Impairment of Long-Lived Assets The Company reviews long-lived assets, including property and equipment, for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If indicators of impairment exist, an impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use of the assets and their eventual disposition are less than their carrying amount. Impairment, if any, is measured as the amount by which the carrying amount of the long-lived assets exceeds their fair value. The Company did not record any impairment of long-lived assets for the years ended December 31, 2023 and December 31, 2022. Leases Upon adoption of ASC 842, Leases , on January 1, 2022, the Company determined if an arrangement is a lease, or contains a lease, at inception. Operating leases are included in operating lease right-of-use, or ROU, assets, operating lease liability, and operating lease liability, net of current portion on the Company’s balance sheets. ROU assets and lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. Since the Company’s lease does not provide an implicit rate, the Company uses its incremental borrowing rate based on the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term and in a similar economic environment at commencement date in determining the present value of future payments. The ROU asset also includes any lease payments made to the lessor at or before the commencement date, minus lease incentives received, and initial direct costs incurred. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. The Company elected certain practical expedients under ASC 842 , including the package of practical expedients, which among other things, allowed the Company to carry forward prior conclusions about lease identification and classification, as well as elections to not record leases with an initial term of twelve months or less on the balance sheet, and to combine the lease and non-lease components in determining the lease liabilities and ROU assets. Deferred Offering Costs The Company capitalizes, within other assets, certain legal, accounting and other third-party fees that are directly related to the Company’s in-process equity financings, including its ATM offering, until such financings are consummated. After consummation of the equity financing, these costs are recorded as a reduction of the proceeds received as a result of the offering. Should a planned equity financing be abandoned, terminated or significantly delayed, the deferred offering costs are immediately written off to operating expenses. Upon closing the IPO, all deferred offering costs were charged against the proceeds from the IPO and recorded in stockholders equity as a reduction of additional paid-in capital. Upon issuing shares under the ATM offering in November 2023, $0.3 million of deferred offering costs were charged against the proceeds from the ATM offering and recorded in stockholders equity as a reduction of additional paid-in capital. As of December 31, 2023 and 2022, $0.4 million and $0.3 million of deferred offering costs related to the ATM offering were recorded on the balance sheets, respectively. Government Programs In May 2021, the Company was awarded a grant by the National Institutes of Health, or NIH, to support research of thalamocortical responsive neurostimulation for the treatment of Lennox-Gastaut Syndrome, a type of epilepsy. The award was issued for a five-year period and has a total budget of over $9.3 million, which includes approximately $5.5 million in funding for subawards to third-party academic epilepsy centers that are collaborating on the study and are subinvestigators on the study funded by NIH. The subawardees are determined by NIH. The Company’s responsibility for the subawards is to submit the funding requests on behalf of the subawardees. The funding of subawards does not have any impact on the Company’s financial statements. Initially funding was approved for the first year beginning June 1, 2021 and provides for reimbursement of qualified direct and indirect expenses in the amount of $0.8 million, including $0.4 million for subawards. Approvals of funds for years two through five are subject to the completion of certain milestones. On July 30, 2022, the Company received funding approval for year two in the amount of $2.6 million, which includes $1.6 million for subawards. On May 25, 2023, the Company received funding approval for year three in the amount of $3.0 million, which includes $1.5 million for subawards. For funds received under the NIH funding agreement, the Company recognizes a reduction in research and development expenses in an amount equal to the qualifying expenses incurred in each period up to the amount awarded by the NIH. Qualifying expenses incurred by the Company in advance of funding by the NIH are recorded within prepaid expenses and other current assets on the balance sheets. Through December 31, 2023, $2.0 million of qualifying expenses have been incurred and funded by the NIH related to the first, second and third year of funding. As of December 31, 2023, the Company recorded prepaid expenses and other current assets of $0.1 million related to the third year of funding. Warranty Warranty costs are accrued based on the Company’s best estimates when management determines that it is probable a charge or liability has been incurred and the amount of loss can be reasonably estimated. While the Company believes that historical experience provides a reliable basis for estimating such warranty cost, unforeseen quality issues or component failure rates could result in future costs in excess of such estimates. The warranty liability as of December 31, 2023 and December 31, 2022 was immaterial. Cost of Goods Sold The Company manufactures its products at its facility. Cost of goods sold consists primarily of costs related to materials, components and subassemblies, manufacturing overhead, direct labor, and reserves for excess and obsolete inventories. A significant portion of the Company’s cost of goods sold currently consists of manufacturing overhead costs. These overhead costs include the cost of facilities, material procurement, inventory control, quality assurance, equipment and operating supervision and management. Cost of goods sold also includes depreciation expense for production equipment and certain direct costs such as shipping costs. Shipping and handling costs are considered a fulfillment activity and are included in cost of goods sold as incurred. Research and Development Expenditures The Company expenses research and development costs as incurred. Research and development expenses consist primarily of engineering, product development, clinical studies to develop and support the Company’s products, regulatory expenses, medical affairs and other costs associated with products and technologies that are in development, including quality assurance. Research and development expenses include employee compensation, including stock-based compensation, supplies, consulting, prototyping, testing, materials, travel expenses, depreciation and an allocation of facility overhead expenses. Additionally, research and development expenses include costs associated with clinical studies including clinical trial design, clinical site reimbursement, data management, travel expenses, the cost of products used for clinical trials and costs associated with regulatory compliance and submitting and maintaining regulatory filings. Advertising Costs The Company expenses advertising costs as incurred. Advertising costs include design and production costs, including website development, physician and patient testimonial videos, written media campaigns, and other items. Advertising costs of $0.7 million and $0.7 million were expensed during the years ended December 31, 2023 and December 31, 2022, respectively. Stock-Based Compensation The Company accounts for stock-based employee compensation in accordance with ASC 718, Stock Compensation . ASC 718 requires the measurement of compensation based on the grant date fair value of the stock option or restricted stock unit (see Note 8). The Company amortizes the fair value of each award on a straight-line basis over the requisite service period of the award. Income Taxes The Company accounts for income taxes under the asset and liability method. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to affect taxable income. Valuation allowances are established when necessary to reduce deferred tax assets to the amounts expected to be realized. The Company assesses all material positions taken in any income tax return, including all significant uncertain positions, in all tax years that are still subject to assessment or challenge by relevant taxing authorities. Assessing an uncertain tax position begins with the initial determination of the position’s sustainability and is measured at the largest amount of benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement. As of each balance sheet date, unresolved uncertain tax positions must be reassessed, and the Company will determine whether (i) the factors underlying the sustainability assertion have changed and (ii) the amount of the recognized tax benefit is still appropriate. The recognition and measurement of tax benefits requires significant judgment. Judgments concerning the recognition and measurement of a tax benefit might change as new information becomes available. Net Loss per Share Attributable to Common Stockholders Basic net loss per common share is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period, without consideration of potentially dilutive securities. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. For purposes of the diluted net loss per share calculation, stock options, common stock subject to repurchase related to early exercise of stock options, and restricted stock units are considered to be potentially dilutive securities. Basic and diluted net loss attributable to common stockholders per share is presented in conformity with the two-class method required for participating securities. The Company considers the shares issued upon the early exercise of stock options subject to repurchase to be participating securities, because holders of such shares have non-forfeitable dividend rights in the event a dividend is paid on common stock. The holders of the shares issued upon early exercise of stock options subject to repurchase do not have a contractual obligation to share in the Company’s losses. As such, the net loss was attributed entirely to common stockholders. Because the Company has reported a net loss for all periods presented, diluted net loss per common share is the same as basic net loss per common share for those periods. Comprehensive Loss Comprehensive loss combines net loss and other comprehensive loss. Other comprehensive loss represents unrealized gains or losses on short-term investments that are reported as a component of stockholders’ equity on the balance sheets. JOBS Act Accounting Election The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date the Company (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these financial statements may not be comparable to companies that comply with new or revised accounting pronouncements as of public company effective dates. Recent Accounting Pronouncements Recently Adopted Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments- Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which amends existing guidance on the impairment of financial assets and adds an impairment model that is based on expected losses rather than incurred losses and requires an entity to recognize as an allowance its estimate of expected credit losses for its financial assets. An entity will apply this guidance through a cumulative-effect adjustment to retained earnings upon adoption (a modified-retrospective approach) while a prospective transition approach is required for debt securities for which an other-than-temporary impairment had been recognized before the effective date. For public business entities that meet the definition of an SEC filer, excluding entities eligible to be smaller reporting companies as defined by the SEC, adoption is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. For SEC filers that are eligible to be smaller reporting companies and for all other entities, this ASU is effective for fiscal years beginning after December 15, 2022, and interim periods within those fiscal years. The Company adopted this ASU effective January 1, 2023. The adoption of this ASU did not have a material impact on the Company’s financial statements and related disclosures. Recent Accounting Pronouncements Not Yet Adopted In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures . The amendments in this ASU require disclosures, on an annual and interim basis, of significant segment expenses that are regularly provided to the chief operating decision maker, or CODM, as well as the aggregate amount of other segment items included in the reported measure of segment profit or loss. This ASU requires that a public entity disclose the title and position of the CODM and an explanation of how the CODM uses the reported measure(s) of segment profit or loss in assessing segment performance and deciding how to allocate resources. Public entities will be required to provide all annual disclosures currently required by Topic 280 in interim periods, and entities with a single reportable segment are required to provide all the disclosures required by the amendments in this ASU and existing segment disclosures in Topic 280. This ASU is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The amendments in this ASU should be applied retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the impact this standard will have on the disclosures within our financial statements. In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures . The ASU requires greater disaggregation of information about a reporting entity's effective tax rate reconciliation as well as information on income taxes paid. The ASU applies to all entities subject to income taxes and is intended to help investors better understand an entity’s exposure to potential changes in jurisdictional tax legislation and assess income tax information that affects cash flow forecasts and capital allocation decisions. The ASU is effective for annual periods beginning after December 15, 2024, with early adoption permitted. The ASU should be applied on a prospective basis although retrospective application is permitted. The Company is currently evaluating the impact this standard will have on the disclosures within our financial statements. |