DXCM, DexCom Inc.

Will it survive?

• Can it pay its interest? 49.8×
  Comfortable
  Operating income $912M ÷ interest expense $18M
  What this means

  Operating profit covers interest with the kind of margin Graham wanted for a defensive holding. Necessary, not sufficient, it says solvent, not cheap.

• How heavy is the debt, net of cash? $323M · 0.4× operating profit
  Modest net debt
  Cash $918M − debt $1.2B
  What this means

  Netting $918M of cash and short-term investments against $1.2B of debt leaves $323M owed, about 0.4× a year's operating profit (1.4× on the gross debt, before the cash). Net debt is the leverage figure that matters: the cash is already set against the debt. Strategic or illiquid investments aren't counted here.

• How long is cash tied up? 151d
  Long (60+ days)
  DSO 95 + DIO 123 − DPO 68 days
  What this means

  Days cash is tied up between paying suppliers and collecting from customers. Lower is better; a long cycle means growth itself eats cash.

Is it a good business?

• Return on invested capital 10%
  Solid through the cycle
  10-yr median, range -27%–23%; 23% latest = NOPAT $701M ÷ invested capital $3.1B
  Industry peers: median 11%
  What this means

  The rate the business earns on the money tied up in it, Buffett's north star, because over time a stock tracks the ROIC beneath it. Above ~15% sustained hints at a moat; a return below the cost of capital (~8%) erodes value as a business grows rather than building it — the test Buffett weighs most. The headline is the median of the last 10 years (it ran 23% most recently), so one peak or trough year doesn't set the verdict. Asset-light businesses (R&D expensed, little capital) read artificially high, pair this with Owner Earnings.

• Owner-earnings margin 17%
  High through the cycle
  10-yr median margin, range 7%–26%; latest $1.2B = operating cash $1.4B − maintenance capex $252M
  Industry peers: median 14%
  What this means

  What an owner could take out without starving the business: operating cash less the maintenance capital it must spend to hold its position — Buffett's owner earnings. That's 26% of revenue this year, a 17% median across 10 years. Treating stock comp as the real expense it is (less $160M of SBC) leaves $1.0B.

• Are earnings backed by cash? 1.72×
  Cash-backed
  Cash from ops $1.4B ÷ net income $836M
  What this means

  How much of reported profit showed up as operating cash. Above 1× is reassuring; well below suggests earnings lean on accruals. One year is noisy, growth and working-capital swings distort it, and this is operating cash, not free cash. Watch the multi-year trend.

How is the cash used?

• Where do the earnings go? 42%
  Returns about half
  Dividends + buybacks $500M ÷ Owner Earnings $1.2B — this fiscal year
  What this means

  Of $1.2B Owner Earnings, $500M (42%) went back to shareholders, $0 dividends, $500M buybacks. Net of $160M stock comp, the real buyback was about $340M. Returning most of it is the mark of a mature business with little left to reinvest at a high return; reinvesting most could mean a long runway, or empire-building. The split doesn't say which; the return earned on it (see ROIC) does. This year's proportion is 42%; across the record (2016–2025) it is 61%, the capital-allocation section below.

• Investing or harvesting? 1.44×
  Expanding
  Capex $364M ÷ depreciation $252M
  What this means

  Descriptive, not a grade. Above ~1× means investing faster than assets wear out (growth, or, sustained for years, today's earnings carrying less depreciation than tomorrow's will). Below means spending less than it's wearing out (efficiency, or a melting asset base). The ratio won't tell you which; the filings will.

The promise and the pay packet

• Is the buyback buying ownership, or mopping up? 3.4%
  The count is genuinely shrinking
  Stock compensation $160M (fiscal 2025), 3.4% of revenue · repurchases $500M · diluted shares -5.1% since 2022
  What this means

  Stock handed to employees is a real cost paid in the owner's own currency: it is charged against profit, but the shares it creates are permanent. Many companies repurchase stock at the same time, which looks like a return of capital and often is not — if the count barely moves, the cash merely cancelled the pay packet and bought the owner nothing. The three states worth telling apart are a count genuinely shrinking, a count standing still despite large repurchases, and a count rising because the issuance was never offset at all.

Graham’s defensive tests · 2 of 4 met

Graham’s numerical criteria for the defensive investor (The Intelligent Investor, ch. 14), run on the filings. A floor of safety, not a buy signal; many fine modern businesses fail his strictest liquidity rules by design.

• Adequate size Pass
  Revenue ≥ $2B · $4.7B
  What this means

  Big enough to weather a storm. Graham's 1972 floor was ~$100M of sales (≈ $700M today); we use a $2B revenue line as a conservative modern stand-in.

• Strong liquidity Near
  Current ratio ≥ 2× · 1.88×
  What this means

  Current assets at least twice current liabilities, near-term bills covered without touching the business. Strict by design: many cash-rich modern firms run leaner and miss it, holding their cushion in longer-dated securities.

• Conservative debt Pass
  Debt ≤ working capital · $1.2B vs $1.9B WC
  What this means

  Graham's rule that borrowings not exceed net current assets. Capital-heavy and buyback-heavy firms routinely fail it, read it next to interest coverage, not alone.

• Earnings stability Miss
  A profit every year (10-yr record) · 3 loss years
  What this means

  Graham wanted earnings in each of the past ten years, the stability a defensive owner leans on.

• Dividend record —
  Uninterrupted dividends · no dividend line tagged in the data
  What this means

  An unbroken dividend was Graham's mark of durability. This record carries no dividends-paid line in any year — common for partnerships, whose distributions file under tags the chain doesn't read — so the criterion is withheld rather than judged on silence.

• Earnings growth —
  Earnings +33% over the record · —
  What this means

  Earnings were negative early in the record, a growth rate isn't meaningful.

• Moderate price —
  P/E ≤ 15 and P/E × P/B ≤ 22.5 · decided by the price
  What this means

  Graham's valuation gate, the wall he kept between a sound business and a sound investment. Three-year average earnings are $1.73/share (latest year $2.22), the averaged base the calculator's gate runs on, and book value is $7.28/share. Enter a price in “What the price implies” just below for the P/E, P/B, and whether it clears. But this is the rule Buffett outgrew: there's no hard P/E law, and a wonderful business can deserve a far richer multiple if the thesis holds, treat it as the bargain-hunter's floor, not a verdict on the price.

Durability & moat, 2016–2025

Whether the record’s returns held, and what the capital reinvested earned.

• Profitable years 7 of 10
  What this means

  Lost money in 3 year(s), look at what happened there before trusting the average.

• Return on capital ≥ 15% 2 of 10 yrs
  What this means

  A moat shows up as a high return on invested capital that holds year after year, not one good vintage.

• Operating margin −12% → 17% (3-yr avg ends)
  What this means

  Through the cycle the operating margin widened — about −12% early to 17% lately, median 11% — pricing power intact or improving.

• Reinvestment, incremental ROIC 22%
  What this means

  Every extra dollar the business reinvested came back at a high incremental return — the lens GBM read for a moat that reinvests rather than merely harvests. The record and the 10-K are where you check whether the rate holds.

• Owner earnings growth +37%/yr
  What this means

  Owner earnings grew about 37% a year over the record.

• Worst year 2018 · −18.1% op. margin
  What this means

  Operations went underwater in 2018, understand why before trusting the good years.