2. Summary of significant accounting policies

Sales 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 Statements of Operations, comes from service contracts, extended warranty contracts and freight revenue for product shipments.

Revenue from product sales is recognized when all of the following criteria are met: (1) persuasive evidence of an arrangement exists; (2) delivery has occurred or services have been rendered; (3) the price to the customer is fixed or determinable; and (4) collectability is reasonably assured. Revenue from product sales is recognized upon shipment of the product. Provisions for estimated returns and discounts are made at the time of shipment. Provisions for standard warranty obligations, which are included in cost of sales revenue on the Statements of Operations, are also provided for at the time of shipment.

Revenue from the sales of the Company’s services is recognized when no significant obligations remain undelivered and collection of the receivables is reasonably assured. The Company offers extended service contracts on its Inogen One concentrator line for periods ranging from 12 to 24 months after the end of the standard warranty period. Revenue from these extended service contracts is recognized in income on a straight-line basis over the contract period.

Accruals for estimated standard warranty expenses are made at the time that the associated revenue is recognized. The provisions for estimated returns, discounts and warranty obligations are made based on known claims and discount commitments and estimates of additional returns and warranty obligations based on historical data and future expectations. The Company accrued $1,078 and $809 to provide for future warranty costs at June 30, 2014 and December 31, 2013, respectively.

 The Company also offers a lifetime warranty for direct-to-consumer sales. For a fixed price, the Company agrees to provide a fully functional oxygen concentrator for the remaining life of the patient. Lifetime warranties are only offered to patients upon the initial sale of oxygen equipment by the Company and are non-transferable. Product sales with lifetime warranties are considered to be multiple element arrangements within the scope of the Accounting Standards Codification (ASC) 605-25—Revenue Recognition-Multiple-Element Arrangements.

There are two deliverables when product that includes a lifetime warranty is sold. The first deliverable is the oxygen concentrator equipment which comes with a standard warranty of three years. The second deliverable is the lifetime warranty that provides for a functional oxygen concentrator for the remaining lifetime of the patient. These two deliverables qualify as separate units of accounting.

The revenue is allocated to the two deliverables on a relative selling price method. The Company has vendor-specific objective evidence of selling price for the equipment. To determine the selling price of the lifetime warranty, the Company uses its best estimate of the selling price for that deliverable 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. A significant estimate used to calculate the price and expense of lifetime warranties is the life expectancy of patients. Based on clinical studies, the Company estimates that 60% of patients will succumb to their disease within three years. Given the approximate mortality rate of 20% per year, the Company estimates on average all patients will succumb to their disease within five years. The Company has taken into consideration that when patients decide to buy an Inogen portable oxygen concentrator with a lifetime warranty, they typically have already been on oxygen for a period of time, which can have a large impact on their life expectancy from the time the Company’s product is deployed.

After applying the relative selling price method, revenue from equipment sales is recognized when all other revenue recognition criteria for product sales are met. Lifetime warranty revenue is recognized using the straight-line method during the fourth and fifth year after the delivery of the equipment which is the estimated usage period of the contract based on the average patient life expectancy.

Shipping and handling costs for sold products and rental assets, shipped to the Company’s customers are included on the Statements of Operations as part of cost of sales revenue and cost of rental revenue, respectively.

Revenue from the sales of used rental equipment is recognized upon delivery and when collectability is reasonably assured and other revenue recognition criteria are met. When a rental unit is sold, the related cost and accumulated depreciation are removed from their respective accounts, and any gains or losses are included in cost of sales revenue on the Statements of Operations.

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 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. To date, the Company has not deferred any amounts associated with the capped rental period. Amounts related to the capped rental period have not been material in the periods presented.

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. 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. Upon determination that an account is uncollectible, it is written-off and charged to the allowance. Amounts billed but not earned due to the timing of the billing cycle are deferred and recognized in income 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 earned, less estimated adjustments. Revenue not billed at the end of the period is reviewed for the likelihood of collections and accrued. The rental revenue stream is not guaranteed and payment will cease if the patient no longer needs oxygen or returns the equipment. Revenue recognized is at full estimated allowable amounts; transfers to secondary insurances or patient responsibility have no net effect on revenue. Rental revenue is earned for that 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 unbilled rental revenue accrual is based on historical trends and estimates of future collectability.

Fair value of financial instruments

The Company’s financial instruments consist of cash and cash equivalents, accounts receivable, accounts payable and accrued expenses, debt and warrants. The carrying values of cash and cash equivalents, accounts receivable and accounts payable and accrued expenses approximate fair values based on the short-term nature of these financial instruments.

The fair value of the Company’s debt approximates carrying value based on the Company’s current incremental borrowing rate for similar types of borrowing arrangements. Imputed interest associated with the Company’s non-interest bearing debt is insignificant and has been appropriate recognized in the respective periods.

The fair value of the Company’s preferred stock warrant liability was estimated using a Monte Carlo valuation model.

Fair value accounting

ASC 820—Fair Value Measurements and Disclosures, creates a single definition of fair value, establishes a framework for measuring fair value in U.S. GAAP and expands disclosures about fair value measurements. ASC 820 emphasizes that fair value is a market-based measurement, not an entity-specific measurement, and states that a fair value measurement should be determined based on assumptions that market participants would use in pricing the asset or liability. Assets and liabilities adjusted to fair value in the balance sheet are categorized based upon the level of judgment associated with the inputs used to measure their fair value. Level inputs, as defined by ASC 820, are as follows:

 

 

The following table summarizes fair value measurements by level at December 31, 2013 for the liabilities measured at fair value on a recurring basis:

 

 

The following table summarizes the fair value measurements using significant Level 3 inputs, and changes therein as of ended June 30, 2014 and December 31, 2013, respectively.

 

 

The preferred stock warrant liability was marked to market at each reporting date and the fair value was estimated using a Monte Carlo valuation model, which takes into consideration the market values of comparable public companies, considering among other factors, the use of multiples of earnings, and adjusted to reflect the restrictions on the ability of the Company’s shares to trade in an active market.

Accounts receivable and allowance for bad debts, returns, and adjustments

Accounts receivable are customer obligations due under normal sales and rental terms. The Company performs credit evaluations of the customers’ financial condition and generally does not require collateral. The allowance for doubtful accounts is maintained at a level that, in management’s opinion, is adequate to absorb potential losses related to accounts receivable and is based upon the Company’s continuous evaluation of the collectability of outstanding balances. Management’s evaluation takes into consideration such factors as past bad debt experience, economic conditions and information about specific receivables. The Company’s evaluation also considers the age and composition of the outstanding amounts in determining their net realizable value.

The allowance is based on estimates, and ultimate losses may vary from current estimates. As adjustments to these estimates become necessary, they are reported in earnings in the periods that they become known. The allowance is increased by bad debt provisions charged to bad debt expense, net of recoveries, in operating expense and is reduced by direct write-offs, net of recoveries.

The Company does not allow returns from providers. Provision for sales returns applies to direct-to-consumer sales only. This reserve is calculated based on actual historical return rates under the Company’s 30-day return program and is applied to the sales revenue for direct-to-consumer sales for the last month of the quarter reported.

The Company also records an allowance for rental revenue adjustments and write-offs, which is recorded as a reduction of rental revenue and rental accounts receivable balances. These adjustments and write-offs result from contractual adjustments, audit adjustments, untimely claims filings or billings not paid due to another provider performing same or similar functions for the patient in the same period, all of which prevent billed revenue becoming realizable. The reserve is based on historical revenue adjustments as a percentage of rental revenue billed during the related period.

When recording the allowance for doubtful accounts, the bad debt expense account (general and administrative expense account) is charged, when recording allowance for sales returns, the sales returns account (contra sales revenue account) is charged, and when recording the allowance for adjustments, the rental revenue adjustments account (contra rental revenue account) is charged.

At June 30, 2014 and December 31, 2013, included in accounts receivable on the balance sheets were earned but unbilled receivables of $2,729 and $1,435, respectively.

Concentration of credit risk

Financial instruments that potentially subject the Company to concentration of credit risk consist principally of cash and cash equivalents and accounts receivable. At times, cash account balances may be in excess of the amounts insured by the Federal Deposit Insurance Corporation (FDIC). However, management believes the risk of loss to be minimal. The Company performs periodic evaluations of the relative credit standing of these institutions and has not experienced any losses on its cash and cash equivalents and short-term investments to date.

Concentration of customers and vendors

The Company sells its products to home medical equipment providers in the United States and in foreign countries on a credit basis. No single customer represented more than 10% of the Company’s total revenue for the six months ended June 30, 2014 and June 30, 2013.  No single customer represented more than 10% of the Company’s total accounts receivable balance as of June 30, 2014, or as of December 31, 2013.

The Company also rents products directly to patients, which resulted in a customer concentration relating to Medicare’s service reimbursement programs. Medicare’s service reimbursement programs (net of patient co-insurance obligations) accounted for 71.7% and 73.3% of rental revenue for the three months ended June 30, 2014 and June 30, 2013, respectively, and based on total revenue were 23.4% and 26.9% for the three months ended June 30, 2014 and June 30, 2013, respectively. Medicare’s service reimbursement programs (net of patient co-insurance obligations) accounted for 72.1% and 74.3% of rental revenue for the six months ended June 30, 2014 and June 30, 2013, respectively, and based on total revenue were 25.0% and 29.5% for the six months ended June 30, 2014 and June 30, 2013, respectively.  Accounts receivable balances relating to Medicare’s service reimbursement programs amounted to $3,300 or 21.1% of total accounts receivable at June 30, 2014 as compared to $2,560, or 25.0% of total accounts receivable at December 31, 2013.

The Company currently purchases raw materials from a limited number of vendors, which resulted in a concentration of three major vendors. The three major vendors supply the Company with raw materials used to manufacture the Company’s products. For the six months ended June 30, 2014, the Company’s three major vendors accounted for 22.6%, 18.1%, and 8.5% respectively, of total raw material purchases.  For the six months ended June 30, 2013, the Company’s three major vendors accounted for 17.3%, 15.5% and 11.1%, respectively, of total raw material purchases.

A portion of revenue is earned from sales outside the United States. Non-U.S. revenue is denominated in U.S. dollars. A breakdown of the Company’s revenue from U.S. and non-U.S. sources for the three months and six months ended June 30, 2014 and June 30, 2013 is as follows:

 

 

Inventories

Inventories are stated at the lower of cost or market. Cost is determined using a standard cost method, including material, labor and manufacturing overhead, whereby the standard costs are updated at least quarterly to reflect approximate actual costs using the first-in, first out (FIFO) method and market represents the lower of replacement cost or estimated net realizable value. The Company records adjustments at least quarterly to inventory for potentially excess, obsolete, slow-moving or impaired items. Inventories consist of the following:

 

 

Property and equipment

Property and equipment are stated at cost. Depreciation and amortization are calculated using the straight-line method over the assets estimated useful lives as follows:

 

 

Expenditures for additions, improvements and replacements are capitalized and depreciated to a salvage value of zero. Repair and maintenance costs are included in cost of revenue on the Statements of Operations. Repair and maintenance expense, which includes labor, parts and freight for rental equipment was $400 and $196 for the three months ended June 30, 2014 and June 30, 2013, respectively, and $790 and $456 for the six months ended June 30, 2014 and June 30, 2013, respectively.

Included within property and equipment is construction in process relating to the design and engineering of tooling, jigs and other machinery.  In addition, this item also includes computer software that has been purchased, but has not completed the final configuration process for implementation into the Company’s systems. These items have not been placed in service, therefore no depreciation and amortization has been recognized in respective periods.

Depreciation and amortization expense related to property and equipment and rental equipment is summarized below for the three months ended June 30, 2014 and June 30, 2013, respectively, and the six months ended June 30, 2014 and June 30, 2013, respectively.

 

 

Property and equipment and rental equipment with associated accumulated depreciation is summarized below for June 30, 2014 and December 31, 2013, respectively.

 

 

Income taxes

The Company accounts for income taxes in accordance with ASC 740—Income Taxes. Under ASC 740, income taxes are recognized for the amount of taxes payable or refundable for the current three months and six months and deferred tax liabilities and assets are recognized for the future tax consequences of transactions that have been recognized in the Company’s financial statements or tax returns. A valuation allowance is provided when it is more likely than not that some portion, or all, of the deferred tax asset will not be realized.

The Company accounts for uncertainties in income tax in accordance with ASC 740-10—Accounting for Uncertainty in Income Taxes. ASC 740-10 prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. This accounting standard also provides guidance on derecognition, classification, interest and penalties, accounting in interim periods, disclosure and transition.

The Company recognizes interest and penalties on taxes, if any, within operations as income tax expense. No significant interest or penalties were recognized during the periods presented.

The Company operates in multiple states. The statute of limitations has expired for all tax years prior to 2010 for federal and 2009 to 2010 for various state tax purposes. However, the net operating loss generated on the federal and state tax returns in prior years may be subject to adjustments by the federal and state tax authorities.

Accounting for stock-based compensation

The Company accounts for its stock-based compensation in accordance with ASC 718, Compensation—Stock Compensation, which establishes accounting for share-based awards, exchanged for employee services and requires companies to expense the estimated fair value of these awards over the requisite employee service period. Stock–based compensation cost is determined at the grant date using the Black-Scholes option pricing model. The value of the award that is ultimately expected to vest is recognized as expense on a straight line basis over the employee’s requisite service period.

As part of the provisions of ASC 718, the Company is required to estimate potential forfeitures of stock grants and adjust compensation cost recorded accordingly. The estimate of forfeitures will be adjusted over the requisite service period to the extent that actual forfeitures differ, or are expected to differ, from such estimates. Changes in estimated forfeitures will be recognized through a cumulative catch-up adjustment in the period of change and will also impact the amount of stock compensation expense to be recognized in future periods.

Business segments

The Company operates in only one business segment – manufacturing, sales, rental and marketing of respiratory products.

Stock split

On November 11, 2013, the Company’s board of directors and stockholders approved a 3:1 reverse stock split. This became effective as of November 12, 2013 and the effect of this event has been reflected in all of the share quantities and per share amounts throughout these financial statements. The shares of common stock retained a par value of $0.001.

Earnings per share

Earnings per share (EPS) is computed in accordance with ASC 260, Earnings per Share, and is calculated using the weighted-average number of common shares outstanding during each period. Diluted EPS assumes the conversion, exercise or issuance of all potential common stock equivalents (which can include dilution of outstanding stock options, redeemable convertible preferred stock and preferred stock warrants, and common stock warrants) unless the effect is to reduce a loss or increase the income per share. For purposes of this calculation, common stock subject to repurchase by the Company, 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.

The shares used to compute basic and diluted net income per share represent the weighted-average common shares outstanding, reduced by the weighted-average unvested common shares subject to repurchase. Further, as the Company’s holders of redeemable convertible preferred stock have the right to participate in any dividend declared on the Company’s common stock, basic and diluted EPS are potentially subject to computation using the two-class method, under which the Company’s undistributed earnings are allocated amongst the holders of common and redeemable convertible preferred stock.

On February 20, 2014, the Company completed an initial public offering (IPO) of 4,411,763 shares of common stock at a price of $16.00 per share. The Company sold 3,529,411 shares of common stock and certain stockholders sold 882,352 shares of common stock. As of March 7, 2014 the underwriters elected to purchase 99,550 additional shares of common stock at the IPO price from the certain selling shareholders.  All redeemable convertible preferred stock and non-redeemable preferred stock-outstanding as of the IPO automatically converted into 14,259,647 shares of common stock.

The computation of EPS is as follows:

 

 

The computations of diluted net income applicable to common shareholders exclude redeemable convertible preferred stock, warrants and common stock options which were anti-dilutive for the three months and six months ended June 30, 2013. There were no anti-dilutive instruments for the three and six months ended June 30, 2014.