Stock fact sheet · data as of
Inspire Medical Systems, Inc. (INSP): fair value, margin of safety and Wheel Score
Healthcare · Medical - Devices · United States · High Growth
Is INSP undervalued?
INSP has a margin of safety of 50%: the stock closed at 70.12 on 16 Oct 2026 against a GLS average fair value of 139.36. 5 of the 8 valuation models that produced a number sit above the price. Our screens treat a discount this large as a strong starting point for a cash-secured put, not as a verdict - the fair value is a model output, and a wide gap can mean the models are missing something the market knows.
The 8 models disagree widely: 10 Cap gives 34.38 while GLS Growth gives 286.71. A spread that wide means the average is sensitive to which methods you trust; the model table below shows where each one lands, and the Quote page lets you switch any of them off.
The nightly engine files INSP under High Growth: revenue and earnings growing fast enough that the growth-based models carry the valuation.
Nine valuation models for INSP
Each model turns the latest filed numbers into a value per share; the GLS fair value is the simple average of the ones that produce a positive number. The last two rows are shown for reference and never enter the average. The Quote page lets you switch any model off and add your own margin of safety.
| Model | Value | vs price | What it measures |
|---|---|---|---|
| DCF | 141.10 | +101% | Present value of the projected free cash flows, discounted at the cost of capital |
| Graham Number | 54.93 | -22% | The most a defensive investor pays for the earnings and book value per share |
| Graham Growth | 267.88 | +282% | Graham's growth formula: EPS × (8.5 + 2 × growth), adjusted for bond yields |
| Lynch | 117.08 | +67% | EPS × the earnings growth rate (PEG of 1), growth capped at 25% |
| GLS Growth | 286.71 | +309% | EPS compounded ten years at the blended growth rate, discounted back at 15% a year |
| 10 Cap | 34.38 | -51% | Owner's earnings (operating cash flow less maintenance capex) capitalised at 10% |
| Payback Time | 160.80 | +129% | Eight years of compounded free cash flow: the price at which the business pays for itself |
| DDM | - | - | Dividend discount model: next year's dividend ÷ (10% − 3% growth); needs a dividend; no value tonight |
| EPV | 52.04 | -26% | Earnings power value: current EPS capitalised at 9% with no growth |
| Zombie (liquidation) | 15.82 | -77% | Current assets less all liabilities, per share: the balance-sheet floor. Not in the average |
| Wall St target | 63.00 | -10% | Analysts' average 12-month price target. Not in the average |
Quality and financial health
On financial health INSP scores 7/9 (Piotroski): most of the nine tests - positive earnings and cash flow, falling debt, rising margins and turnover - are passed, which is the kind of balance sheet a wheel trader is happy to be assigned. The GLS Moat score is low at 4.9 out of 10, which says the ten-year record of revenue, earnings, margins and returns on capital has been inconsistent - growth and shocks rather than steady compounding.
Returns on capital are high - ROIC 17.9%, ROE 18.6%, ROA 16.0% - with debt at 0.04 times equity and a free-cash-flow yield of 5.8%.
Inspire Medical Systems, Inc. pays no dividend, so the DDM model does not apply and a covered-call holder earns only the premium and any price gain. Revenue comes mainly from Operating 100% (quarter Q2 FY2026).
Institutional ownership scores 10/10, insider activity 1/10 and Congressional trading 5/10 on the GLS smart-money scales.
| Piotroski F-score | 7 / 9 | ROIC | 17.9% |
|---|---|---|---|
| GLS Moat | 4.9 / 10 | ROE | 18.6% |
| Debt / equity | 0.04 | ROA | 16.0% |
| Free-cash-flow yield | 5.8% | Payout ratio | 0% |
| Institutions | 10 / 10 | Insiders · Congress | 1 · 5 / 10 |
Wheel Score 77: Good
INSP scores 77 out of 100 on the Wheel Score (Good band, 65-79). The score blends the margin of safety (Value, 25/25), Piotroski health (16/20), the GLS moat (7/15), the option premium on offer (15/20) and how easily the stock trades (14/20). Moat (7/15) is the part holding the score back.
Implied volatility is 79% on the near-the-money contracts 20-60 days out - above the 60% ceiling of the sweet spot. Premiums are large, but the Wheel Score tapers the Premium points (15 of 20) because volatility this high usually comes with a reason. Chain open interest is 5,985 contracts across all expiries - enough for the wheel at normal size.
Volume runs at 526k shares a day on a market cap of $2.0B, with a beta of 0.73 - a low beta, so day-to-day moves are smaller than the market's; the Stability part of the Wheel Score gives that 14 of 20.
| Part | Points | From | |
|---|---|---|---|
| Value | 25 / 25 | 50% margin of safety | |
| Health | 16 / 20 | Piotroski 7/9 | |
| Moat | 7 / 15 | moat 4.9/10 | |
| Premium | 15 / 20 | implied volatility 79% | |
| Stability | 14 / 20 | 526k shares/day, $2.0B cap, beta 0.73 |
The Wheel Score ranks ~7,400 US stocks for selling cash-secured puts and covered calls; it is updated nightly and is not a recommendation. The walkthrough lesson shows how the score fits into a trade, start to finish.
Upcoming events
The next earnings report is due on 2 Nov 2026 (after the close), 17 days away; a 30-45-day put sold today would expire after it, which is worth weighing against the premium.
Earnings, dividend, IPO, split and economic calendars for the whole market, filterable to your watchlists.
Similar stocks in Medical - Devices
The 12 companies below are the closest to Inspire Medical Systems, Inc. by market cap within the Medical - Devices industry, each with its own fact sheet; the Compare page puts up to eight of them side by side.
| Stock | Close | Fair value | MoS | Wheel | Mkt cap |
|---|---|---|---|---|---|
| AXGN AxoGen, Inc. | 35.63 | 1.71 | -1982% | 40Weak | $2.1B |
| BFLY Butterfly Network, Inc. | 7.85 | - | - | 44Weak | $2.1B |
| ESTA Establishment Labs Holdings Inc. | 61.36 | - | - | 45Weak | $1.8B |
| UFPT UFP Technologies, Inc. | 291.10 | 250.97 | -16% | 65Good | $2.3B |
| ATEC Alphatec Holdings, Inc. | 10.93 | 7.18 | -52% | 45Weak | $1.7B |
| NVCR Novocure Ltd | 14.41 | - | - | 45Weak | $1.7B |
| TMDX TransMedics Group, Inc. | 75.52 | 116.64 | +35% | 68Good | $2.6B |
| NEOG Neogen Corporation | 12.27 | 4.48 | -174% | 45Weak | $2.7B |
| CNMD CONMED Corporation | 47.14 | 79.07 | +40% | 82Prime | $1.4B |
| IRMD IRadimed Corporation | 89.37 | 44.42 | -101% | 48Weak | $1.1B |
| IRTC iRhythm Technologies, Inc. | 109.35 | 55.77 | -96% | 45Weak | $3.6B |
| ENOV Enovis Corporation | 19.35 | 51.34 | +62% | 45Weak | $1.1B |
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Start free See the Sunday ScanQuestions about INSP
Is INSP undervalued right now?
By the GLS models, yes: at 70.12 the stock is 50% below the average fair value of 139.36 (data as of 16 Oct 2026). Whether the discount is deserved is the question to research next.
What is the Wheel Score of INSP and what does it mean?
INSP scores 77 out of 100 (Good). The Wheel Score blends the margin of safety (25 points), Piotroski health (20), the GLS moat (15), the option premium on offer (20) and trading stability (20) into one number that ranks stocks for the wheel strategy - selling cash-secured puts, then covered calls if assigned. 80 and above is Prime, 65-79 Good, 50-64 Fair, under 50 Weak.
What is the GLS fair value for INSP?
139.36 per share as of 16 Oct 2026 - the simple average of the 8 valuation models (out of nine: DCF, Graham Number, Graham Growth, Lynch, GLS Growth, 10 Cap, Payback Time, DDM and EPV) that produced a positive value. The models run every night on the latest filings; the Quote page lets you switch any of them off and add a margin of safety of your own.
When does Inspire Medical Systems, Inc. report earnings next?
The next earnings report is due on 2 Nov 2026 (after the close), 17 days from the data date of 16 Oct 2026. The Calendars page lists every upcoming report with its time of day.
Does INSP have listed options, and how liquid are they?
Yes. The nightly snapshot found 328 listed contracts with 5,985 open interest across all expiries and implied volatility of 79% on the near-the-money contracts. The Options scanner lists the cash-secured put and covered call set-ups with premium and annualised yield worked out.