2. Basis of presentation and summary of significant accounting policies

The accompanying consolidated financial statements are unaudited. The consolidated balance sheet at December 31, 2017 has been derived from the audited consolidated financial statements of the Company. The accompanying consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (U.S. GAAP) for interim financial information, and in management’s opinion, includes all adjustments, consisting of only normal recurring adjustments, necessary for the fair statement of the Company’s financial position, its results of operations, stockholders’ equity and cash flows for the interim periods presented. The results of operations for the three and six months ended June 30, 2018 are not necessarily indicative of the results to be expected for the full fiscal year or any other period.

The accompanying consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto contained in the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission (SEC) on February 27, 2018. There have been no significant changes in the Company’s accounting policies from those disclosed in its Annual Report on Form 10-K filed with the SEC on February 27, 2018.

Basis of consolidation

The consolidated financial statements include the accounts of Inogen, Inc. and its wholly owned subsidiaries.  All intercompany balances and transactions have been eliminated.

Use of estimates

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period.  Management bases these estimates and assumptions upon historical experience, existing and known circumstances, authoritative accounting pronouncements and other factors that management believes to be reasonable. Significant areas requiring the use of management estimates relate to revenue recognition and determining the stand-alone selling price (SSP) of performance obligations, inventory and rental asset valuations and write-downs, accounts receivable allowances for bad debts, returns and adjustments, warranty expense, stock compensation expense, depreciation and amortization, income tax provision and uncertain tax positions, fair value of financial instruments, and fair value of acquired intangible assets and goodwill. Actual results could differ from these estimates.

Revenue

The Company generates revenue primarily from sales and rentals of its products. The Company’s products consist of its proprietary line of oxygen concentrators and related accessories. Other revenue, which is included in sales revenue on the consolidated statements of comprehensive income, consists of repair services and freight revenue for product shipments.

Sales revenue

Revenue is recognized upon transfer of control of promised products or services to customers in an amount that reflects the consideration the Company expects to receive in exchange for those products or services. Revenue from product sales is generally recognized upon shipment of the product but is deferred for certain transactions when control has not yet transferred to the customer.

The Company’s product is generally sold with a right of return and the Company may provide other incentives, which are accounted for as variable consideration when estimating the amount of revenue to recognize.  Returns and incentives are estimated at the time sales revenue is recognized. The provisions for estimated returns are made based on known claims and estimates of additional returns based on historical data and future expectations. Sales revenue incentives within the Company’s contracts are estimated based on the most likely amounts expected on the related sales transaction and recorded as a reduction to revenue at the time of sale in accordance with the terms of the contract. Accordingly, revenue is recognized net of allowances for estimated returns and incentives.

The Company also offers a lifetime warranty for direct-to-consumer sales of its portable concentrators. For a fixed price, the Company agrees to provide a fully functional portable oxygen concentrator for the remaining life of the patient. Lifetime warranties are only offered to patients upon the initial sale of portable oxygen concentrators by the Company and are non-transferable. Lifetime warranties are considered to be a distinct performance obligation that are accounted for separately from its sale of portable oxygen concentrators with a standard warranty of three years.

The revenue is allocated to the distinct lifetime warranty performance obligation based on a relative SSP method. The Company has vendor-specific objective evidence of the selling price for its equipment. To determine the selling price of the lifetime warranty, the Company uses its best estimate of the SSP for the distinct performance obligation as the lifetime warranty is neither separately priced nor is the selling price available through third-party evidence. To calculate the selling price associated with the lifetime warranties, management considered the profit margins of the overall business, the average estimated cost of lifetime warranties and the price of extended warranties. Revenue from the distinct lifetime warranty is deferred after the delivery of the equipment for three years and recognized on a straight-line basis during the fourth and fifth year, which is the estimated usage period of the contract based on the average patient life expectancy.

Revenue from the sale of the Company’s repair services is recognized when the performance obligations are satisfied, and collection of the receivables is probable. Other revenue from sale of replacement parts and non-warranty repair services is generally recognized when product is shipped to customers.

Freight revenue consists of fees associated with the deployment of products internationally and domestically when expedited freight options are requested or when minimum order quantities are not met. Freight revenue is generally recognized upon shipment of the product but is deferred if control has not yet transferred to the customer. Shipping and handling costs for sold products and rental assets shipped to the Company’s customers are included on the consolidated statements of comprehensive income as part of cost of sales revenue and cost of rental revenue, respectively.

The payment terms and conditions of customer contracts vary by customer type and the products and services offered.  For certain products or services and customer types, the Company requires payment before the products or services are delivered to the customer.  The timing of sales revenue recognition, billing and cash collection results in billed accounts receivable and deferred revenue in the consolidated balance sheet.

Contract liabilities primarily consist of deferred revenue related to lifetime warranties on direct-to-consumer sales revenue when cash payments are received in advance of services performed under the contract. The contract with the customer states the final terms of the sale, including the description, quantity, and price of each product or service purchase.  The increase in deferred revenue related to lifetime warranties for the six months ended June 30, 2018 was primarily driven by $3,300 of payments received in advance of satisfying the distinct performance obligation, partially offset by $615 of revenues recognized that were included in the deferred revenue balance as of December 31, 2017.  Lifetime warranties on direct-to-consumer sales revenue of $13,505 and $10,820 as of June 30, 2018 and December 31, 2017, respectively, are classified within deferred revenue – current and noncurrent deferred revenue in the consolidated balance sheet.

The Company elected to apply the practical expedient in accordance with Accounting Standards Codification (ASC) 606—Revenue Recognition and did not evaluate contracts of one year or less for the existence of a significant financing component.  The Company does not expect any revenue to be recognized over a multi-year period.

The Company’s sales revenue is primarily derived from the sale of its Inogen One systems, Inogen At Home systems, and related accessories to individual consumers, home medical equipment providers, distributors, the Company’s private label partner and resellers worldwide.  Sales revenue is classified into two areas: business-to-business sales and direct-to-consumer sales. The following table sets forth the Company’s sales revenue disaggregated by sales channel and geographic region:

Rental revenue

The Company recognizes equipment rental revenue over the non-cancelable lease term, which is one month, less estimated adjustments, in accordance with ASC 840 —Leases. The Company has separate contracts with each patient that are not subject to a master lease agreement with any third-party payor. The Company evaluates the individual lease contracts at lease inception and the start of each monthly renewal period to determine if there is reasonable assurance that the bargain renewal option associated with the potential capped free rental period would be exercised. Historically, the exercise of such bargain renewal option is not reasonably assured at lease inception and most subsequent monthly lease renewal periods. If the Company determines that the reasonable assurance threshold for an individual patient is met at lease inception or at a monthly lease renewal period, such determination would impact the bargain renewal period for an individual lease. The Company would first consider the lease classification issue (sales-type lease or operating lease) and then appropriately recognize or defer rental revenue over the lease term, which may include a portion of the capped rental period.

The lease term begins on the date products are shipped to patients and are recorded at amounts estimated to be received under reimbursement arrangements with third-party payors, including Medicare, private payors, and Medicaid. Due to the nature of the industry and the reimbursement environment in which the Company operates, certain estimates are required to record net revenue and accounts receivable at their net realizable values. Inherent in these estimates is the risk that they will have to be revised or updated as additional information becomes available. Specifically, the complexity of many third-party billing arrangements and the uncertainty of reimbursement amounts for certain services from certain payors may result in adjustments to amounts originally recorded. Such adjustments are typically identified and recorded at the point of cash application, claim denial or account review. The Company adjusts revenue for historical trends on revenue adjustments due to timely filings, deaths, hospice, and other types of analyzable adjustments on a monthly basis. Accounts receivable are reduced by an allowance for doubtful accounts which provides for those accounts from which payment is not expected to be received although product was delivered, and revenue was earned. The determination that an account is uncollectible, and the ultimate write-off of that account occurs once collection is considered to be not probable, and it is written-off and charged to the allowance at that time. Amounts billed but not earned due to the timing of the billing cycle are deferred and recognized in rental revenue on a straight-line basis over the monthly billing period. For example, if the first day of the billing period does not fall on the first of the month, then a portion of the monthly billing period will fall in the subsequent month and the related revenue and cost would be deferred based on the service days in the following month.

Rental revenue is recognized as upon transfer of control of promised products or services to customers in an amount that reflects the consideration the Company expects to receive in exchange for those products or services, less estimated adjustments. Revenue not billed at the end of the period is reviewed for the probability of collection and accrued if collection is probable. Rental revenue is not guaranteed, and payment will cease if the patient no longer needs oxygen or returns the equipment. Rental revenue is recognized at estimated allowable amounts that reflect the full consideration the Company expects to receive in exchange for the equipment; transfers to secondary insurances or patient responsibility have no net effect on revenue. Rental revenue is earned for that entire month if the patient is on service on the first day of the 30-day period commencing on the recurring date of service for a particular claim, regardless if there is a change in condition or death after that date.

Included in rental revenue are unbilled amounts for which the revenue recognition criteria had been met as of period-end but were not yet billed to the payor. The estimate of net unbilled rental revenue recognized is based on historical trends and estimates of future collectability. In addition, the Company estimates potential future adjustments and write-offs of these unbilled amounts and includes these estimates in the allowance for adjustments and write-offs of rental revenue which is netted against gross receivables.

Recently issued accounting pronouncements not yet adopted

In February 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2016-02, Leases (Topic 842). The new guidance will require organizations that lease assets—referred to as “lessees”—to recognize on the balance sheet the assets and liabilities for the rights and obligations created by those leases with lease terms of more than twelve months. This will increase the reported assets and liabilities – in some cases very significantly. ASU No. 2016-02 will take effect for public companies for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption will be permitted for all entities. In January 2018, the FASB issued ASU No. 2018-01, Land Easement Practice Expedient for Transition to Topic 842, which is an amendment to ASU No. 2016-02 that offers a practical expedient for accounting for land easements.  This practice expedient allows an entity the option of not evaluating existing land easements under ASC 842.  New or modified land easements will still require evaluation under ASC 842 on a prospective basis beginning on the date of adoption. While the Company continues to evaluate the effect of adopting this guidance on the consolidated financial statements and related disclosures, the Company expects its operating leases, as disclosed in Note 8 – Commitments and contingencies, will be subject to the new standard. The Company intends to recognize right-of-use assets and operating lease liabilities on the consolidated balance sheets upon adoption, which will increase the Company’s total assets and liabilities. The Company plans to adopt the standard on January 1, 2019.

In June 2016, the FASB issued ASU No. 2016-13, Accounting for Credit Losses (Topic 326). The new standard requires the use of an “expected loss” model on certain types of financial instruments.  The standard also amends the impairment model for available-for-sale debt securities and requires estimated credit losses to be recorded as allowances instead of reductions to amortized cost of the securities.  The ASU is effective for fiscal years beginning after December 15, 2019, and interim periods within those years, with early adoption permitted.  The Company is evaluating the new guidance but does not expect it to have a material impact on the Company’s consolidated financial statement presentation or results.

In January 2017, the FASB issued ASU No. 2017-04, Simplifying the Test for Goodwill Impairment. The new guidance eliminates step two of the goodwill impairment test. Under the new guidance, an entity should recognize an impairment charge for the amount by which a reporting unit’s carrying value exceeds its fair value. The ASU is effective for fiscal years beginning after December 15, 2019, with early adoption permitted. The Company is currently evaluating the effect of the new guidance but does not expect it to have a material impact on the Company’s consolidated financial statement presentation or results.

In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging, which changes both the designation and measurement guidance for qualifying hedging relationships and the presentation of hedge results, in order to better align an entity’s risk management activities and financial reporting for hedging relationships. The amendments expand and refine hedge accounting for both nonfinancial and financial risk components and align the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements. ASU No. 2017-12 is effective for annual reporting periods beginning after December 15, 2018, including interim periods within those annual reporting periods, with early adoption permitted. The Company is still evaluating the impact that this guidance will have on the Company’s consolidated financial statement presentation or results and has not yet determined whether the Company will early adopt ASU No. 2017-12.

In January 2018, the FASB issued ASU No. 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. The new guidance permits entities the option to reclassify tax effects that are stranded in accumulated other comprehensive income as a result of the implementation of the Tax Cuts and Jobs Act to retained earnings.  The Company intends to adopt the standard on January 1, 2019 and does not expect it to have a material impact on the Company’s consolidated financial statement presentation or results.

In June 2018, the FASB issued ASU No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting. The new guidance modifies the accounting for nonemployee share-based payments.  The Company intends to adopt the standard on January 1, 2019 and does not currently have an impact on the Company’s consolidated financial statement presentation or results.

Recently adopted accounting pronouncements

In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, which supersedes nearly all existing revenue recognition guidance under U.S. GAAP. The core principle of ASU No. 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration to which an entity expects to be entitled for those goods or services. ASU No. 2014-09 defines a five-step process to achieve this core principle and, in doing so, more judgment and estimates may be required within the revenue recognition process than are required under existing U.S. GAAP.  In March 2016, the FASB issued ASU No. 2016-08, Revenue with Contracts with Customers: Principal versus Agent Considerations (Reporting Revenue Gross versus Net), which is an amendment to ASU No. 2014-09 that improved the operability and understandability of implementation guidance versus agent considerations by clarifying the determination of principal versus agent.  The Company completed its adoption plan including assessment of the Company’s revenue streams and analysis of all outstanding contracts by application of the five-step model to those contracts and revenue streams.  The Company adopted the standard on January 1, 2018, using the modified retrospective method. The Company finalized its analysis and the adoption of this standard did not have a material impact on the consolidated financial statements and internal controls over financial reporting.  

In January 2017, the FASB issued ASU No. 2017-01, Clarifying the Definition of a Business. The new guidance revises the definition of a business and provides new guidance in evaluating when a set of transferred assets and activities is a business. The Company adopted this standard on January 1, 2018. The adoption of this ASU did not have a material effect on the Company’s consolidated financial statement presentation or results.

Business segments

The Company operates and reports in only one operating and reportable segment – development, manufacturing, marketing, sales, and rental of respiratory products. Management reports financial information on a consolidated basis to the Company’s chief operating decision maker.