Inogen Inc (INGN) stock intrinsic value fair value estimate & owner earnings analysis

Inogen makes portable oxygen concentrators, battery-powered devices that let people with chronic lung disease (mainly COPD) carry medical oxygen with them instead of relying on tanks. It sells them in three ways: to home-medical-equipment providers and distributors in the U.S. (U.S. sales of $156.5 million in 2025), to distributors and partners abroad (international sales of $138.8 million, about 85% of it in Europe), and by renting devices directly to U.S. patients, billed mostly to Medicare and private insurers (rental revenue of $53.4 million). Total 2025 revenue was $348.7 million. In 2025 the company also began selling products made by Jiangsu Yuwell, a Chinese respiratory-device maker: the Voxi 5 stationary concentrator and, from November 2025, Aurora CPAP masks. Yuwell's Hong Kong affiliate bought 2.63 million new shares for $27.2 million in January 2025, which is roughly a 10% stake. Yuwell is a significant shareholder and supplier, but it does not control the company. Inogen also owns the Simeox airway-clearance device, which came with its 2023 purchase of Physio-Assist. Two very different businesses have carried the Inogen name. From 2016 to 2019, when its lightweight concentrators had little competition and it sold heavily to patients directly, Inogen turned $1.43 to $1.98 per share of cash into what we call owner earnings: cash from operations, minus the cost of keeping the rental fleet and plant running, minus stock-based pay, with working-capital timing swings removed. Since 2020 that figure has been negative every year: -$0.14, -$0.09, -$1.79, -$2.91, -$1.05 and -$0.36 per share (2020 to 2025). Competitors caught up, the direct-to-patient model stopped paying, and prices fell. We value only the business as it exists now, so our starting point is the 2020 to 2025 record. The median of those years, and also of the two years since the 2023 restructuring, is a loss of about $0.70 per share a year. Accounting choices that matter here. Inogen adds back large "provisions" in its cash-flow statement for returns, bad debts, insurer rate adjustments and inventory write-downs. These are real, recurring revenue reductions and costs, so we count them as costs and do not add them back. Rental devices bought each year ($7.9 million in 2025, $21.3 million in 2023) are treated as a real cost of staying in business, the same as factory spending. The $52.2 million technology write-off in 2022, the $32.9 million impairment in 2023, the changes in the value of acquisition earnouts, and the $9.8 million earnout payment in 2025 are all treated as the price of past acquisitions rather than ongoing operating costs. Inogen has no borrowings. It held about $105.5 million in cash and short-term investments at June 30, 2026, down from $119.6 million at the end of 2025. We value the business as that cash plus the present value of what the operations will earn or lose from here, discounted at 6%. To avoid counting the cash twice, we remove the interest it earns ($4.4 million in 2025) from the operating figures. On that basis operations lost about $30 million in 2024 and $14 million in 2025. What the recent numbers say. Revenue grew 3.9% in 2025, and 3.2% in the first half of 2026 ($180.2 million against $174.6 million). The company sold 20% more oxygen systems in 2025 (189,400 units) but sales revenue rose only 5.9%, so the average selling price fell roughly 12%. Sales gross margin slipped from 46.7% to 44.5%, and total gross profit was flat ($154.3 million against $154.7 million). U.S. rental revenue fell 6.3% because there were fewer patients on service and more of them were on lower-paying private insurance. All of the 2025 improvement came from cutting costs: operating expenses before impairments fell from about $203 million in 2023 to $197 million in 2024 and $184 million in 2025. The first half of 2026 shows no further gain. The operating loss was $14.4 million, against $13.8 million a year earlier. The loss improved by about $16 million in the last completed year, but the latest six months have been flat, so our base case assumes no improvement in the first year. Base case ($4.14 per share): operations lose about $14 million in 2026. Losses then narrow by about $3 million a year as continued European demand, the new Yuwell-sourced products and cost discipline slowly outrun price erosion and the shrinking rental book. Operations break even around 2031 and settle at a modest $7 million a year, about a 2% margin. That level holds for another decade on the strength of Inogen's installed base, brand and distribution network. Roughly $40 million of cash is used up before the turn. Almost all of the base value is the cash on hand. The operations themselves are worth close to nothing on this path. Bear case ($0.72 per share): falling prices and the shrinking rental business cancel out the cost cuts. Operating losses run at the 2024 to 2025 median of about $20 to $22 million a year for five years and use up most of the cash. By then Inogen has to shrink sharply, sell itself or raise money on poor terms, and we assign nothing beyond the cash that is left. This case does not require the company to owe more than it is worth. It is a slow burn of the cushion that currently backs the shares. Bull case ($9.63 per share): the company's own levers work. International unit growth continues at the 2025 pace, the Voxi, Aurora and Simeox products add meaningful volume, and operating costs stay near today's level. Operations break even in 2028 and reach about $20 million a year of owner earnings (about $0.74 per share) by the early 2030s. That is still well below the $1.43 to $1.98 per share the company earned in 2016 to 2019. It is sustained through the mid-2040s and then fades. What would make this wrong: a stabilisation of selling prices, together with renewed growth in gross profit, would support the bull case. If the next rounds of Medicare or insurer rate changes cut rental economics further, or if Inogen takes on another acquisition that consumes the cash, the bear case moves closer. Because most of today's value is cash that is still being spent, the key thing to watch is whether quarterly operating losses keep shrinking. Until they do, the shares are worth roughly their cash, minus whatever is still to be burned.