Costar Group Inc (CSGP) stock analysis
Costar Group Inc (CSGP) clears 3 of this site's 8 mechanical value filters, 2 of 8 Buffett-style checks and 1 of 5 Lynch-style checks. A free-cash-flow DCF does not fit real estate companies, so no margin of safety is shown. Its earnings quality rates Mixed and it returns +2.1% to shareholders net of dilution. Figures are as of October 23, 2026, from SEC filings and market data refreshed weekly; this is educational analysis, not investment advice.
Data as of October 23, 2026. Refreshed weekly from SEC filings and market data.
What does Costar Group do?
CoStar Group sells commercial real estate data and runs listing sites such as Apartments.com, Homes.com and LoopNet.
Brands and businesses it owns
- Apartments.com
- Homes.com
- LoopNet
- CoStar
- Ten-X
What stands out about Costar Group?
- Misses 3 of the 8 value filters. It fails Market Cap > $25B ($14.4B), Trailing P/E < 25 (195.55) and PEG Ratio < 1.5 (4.66); the other 3 pass and 2 were not evaluated. See every filter.
- Weakest against peers: P/E ratio. At 195.6× (peer median 31.5×) it ranks 29th of 29 among real estate stocks this site tracks. See the ranking.
- Earnings quality: Mixed · 3 watch. Beneish M-score −2.15 (grey zone), mostly from more assets of uncertain value (often acquisitions) · accruals −4.3% of assets · 252% of profit arrived as cash · stock comp 6.0% of revenue · share count +1.7% a year. From the latest 10-K (year to Dec 2025). See the Earnings Quality Screener.
- Insiders have been buying. 1 open-market purchase was reported in SEC Form 4 filings in the last 90 days, about $54.0 million in all. See the Insider Buying Tracker.
How has Costar Group's share price moved?
The interactive price chart needs JavaScript.
Is Costar Group undervalued? The value diligence check
Every value-investing signal this site computes for this stock, gathered in one place: the same real numbers from the tools below, not a new score.
- Margin of safety (DCF) n/a (Real Estate)
- P/E vs. its own history 195.6x · near the cheap end Real range: 83.1x–4041.1x over 5 years (net income per diluted share from each fiscal year's 10-K, paired with the real closing price at that fiscal year-end).
- Wall St. analyst rating Buy · 3.75/5 28 analysts this month: 6 strong buy, 10 buy, 11 hold, 1 sell, 0 strong sell (Finnhub).
- Altman Z″-Score (bankruptcy risk) n/a (Real Estate)
- Earnings quality (is the profit real?) Mixed · 3 watch Beneish M-score −2.15 (grey zone), mostly from more assets of uncertain value (often acquisitions) · accruals −4.3% of assets · 252% of profit arrived as cash · stock comp 6.0% of revenue · share count +1.7% a year. From the latest 10-K (year to Dec 2025) - see the Earnings Quality Screener for how each check is scored.
- Shareholder yield (cash back to owners) +2.1% net Latest fiscal year (2025): dividends 0.0% + buybacks 3.5% − stock comp 1.3%, as a share of today's market cap. Over 14 years its split-adjusted share count rose 79%. See Shareholder Yield Leaders.
- Capital needed to grow (See's test) n/a (bank, insurer, lender or REIT)
- PEG (growth at a reasonable price) 4.66 · Well above fair P/E 195.6× ÷ 42.0% a year of growth behind it. 407th lowest of 447 stocks with a usable PEG. Lynch's fair value is a PEG of 1; a very high PEG usually means almost no growth, a very low one a profit spike. See PEG Ratio Ranking.
- Compounder lenses (4) 1 of 4 · misses capital-light (n/a), cash back, price Capital-light growth: cannot be measured (bank, insurer, lender or REIT); Profit is real: cleared; Cash to owners: not cleared (+0.3% a year net); Fair price (PEG): not cleared (PEG 4.66, over 1.5). See Compounders at a Fair Price, which also lets you move the PEG bar.
- Munger's Inversion Check 1 flag
- Standing vs. sector peers 0 of 3 measures above the median Compared with the 29 other real estate stocks this site tracks: 0 in the top third, 3 in the bottom third.
How does Costar Group compare with its peers?
0 of 3 measures sit above the median of the 29 other real estate stocks tracked here, 3 in the bottom third.
- P/E ratiolower is cheaper · peer median 31.5× 195.6× ✕29th of 29
- Return on equityhigher is better · peer median 8% 1% ✕28th of 30
- Net marginhigher is better · peer median 20.9% 2.1% ✕29th of 30
Peers are the stocks this site tracks in the same sector group, not every listed competitor. The bar runs from the weakest peer (left) to the strongest (right); the tick is the middle. Measures that don't apply to a sector (cash-flow yield for banks, debt for financials) are left out.
What would Buffett & Lynch say?
Buffett's checklist is built around durable, profitable businesses bought at sensible prices, and CSGP doesn't clear enough of it yet. In its favor: CSGP carries a conservative amount of debt relative to equity, and earns many times its interest expense, so debt service isn't a worry. Where it comes up short: CSGP isn't clearing the return-on-equity bar he'd want to see right now, and its five-year average return on equity falls short too, so this isn't just a one-off dip, runs thinner pretax margins than he'd like to see, hasn't grown earnings per share fast enough over five years to impress him, is trading above what a conservative discounted-cash-flow estimate says it's worth right now, and trades rich relative to owner earnings, the real cash the business could pay out.
- ROE (TTM) > 11% ✕
- ROE (5yr avg) > 11% ✕
- Debt/Equity < 0.5 ✓
- Pretax margin > 15% ✕
- EPS growth (5yr) > 7% ✕
- Interest coverage > 5x ✓
- Trading below intrinsic value (DCF) ✕
- Price vs. owner earnings < 25x ✕
- Bonus: returning capital via buybacks FY2025
Lynch looked for growth stories that weren't overpriced for that growth, and CSGP falls short of his bar. In its favor: CSGP isn't over-leveraged for a company of its type. Where it comes up short: CSGP doesn't pay much of a dividend, which is the main reason to own a slow grower in the first place, isn't even growing at the modest pace he'd expect from a slow grower, is priced too rich for how little growth is actually left in the business, and trades expensive relative to the cash it actually generates.
- Dividend yield > 2.5% ✕
- EPS growth 0%-10% ✕
- Debt/Equity < 0.6 ✓
- P/E < 20 ✕
- Price/FCF < 25 ✕
- Bonus: insiders buying (90d) 1 buy, ~$54.0M
Quantitative approximations of each investor's documented approach, not endorsed by either investor or their estates - commentary, not this site's actual ranking criteria. Buffett never published a numeric checklist: only 2 of his 8 checks here trace to his own documented concepts ("owner earnings," from his 1986 shareholder letter, and "price is what you pay, value is what you get," his case against fixed P/E/P/B ceilings) - the other 6 (ROE, debt, margins, growth, interest coverage) use commonly-cited thresholds that are not numbers he himself published. The 8 hard filters below (plus the Munger check and Graham margin of safety) are this site's real, mechanical screen and are computed completely independently of the checklists above.
Berkshire Hathaway's own filing
Which of the 8 value filters does Costar Group pass?
- Market Cap > $25B $14.4B
- Trailing P/E < 25 195.55
- PEG Ratio < 1.5 4.66
- Price/Book < 8 1.81
- Price/Sales < 7 4.05
- EPS Growth YoY > -5% +831.5%
- vs 50-day MA (±12%) Not evaluated †
- vs 200-day MA (±12%) Not evaluated †
What is Costar Group's margin of safety?
A standard free-cash-flow DCF doesn't fit how real estate companies report cash flow.
Where is Costar Group in its 52-week range?
What is the short interest in Costar Group?
13,284,736 shares short as of 2026-09-30 (FINRA settlement date). Reported twice a month, so this only changes roughly every two weeks, not daily.
What could go wrong with Costar Group? Munger's inversion check
"Invert, always invert." Instead of reasons to buy, these are reasons to hesitate, not a verdict, and not everything worth knowing about a business.
- Margin of safety, even in the bull case n/a (Real Estate)
- Short interest under 5% of float 3.3%
- Passes most of the 6 fundamental filters 3/6 passed
Doesn't cover circle of competence, management quality, or accounting concerns: those need judgment, not data.
How much have Costar Group shareholders gained per year?
Earnings growth per share plus dividend.
An earnings-based proxy, not a stock-price total return - it doesn't capture multiple expansion/contraction or reinvested dividends. EPS from CSGP's own 10-K filings; dividend yield is the current trailing yield on today's price, from the same weekly fetch as the rest of this site.
What do Costar Group's 10-year financials show?
From CSGP's own 10-K filings (SEC EDGAR): up to the last 10 fiscal years. Press any year's bars for the exact figures.
Frequently asked questions about Costar Group
What kind of company is Costar Group?
CoStar Group sells commercial real estate data and runs listing sites such as Apartments.com, Homes.com and LoopNet. Brands and businesses it owns include Apartments.com, Homes.com, LoopNet, CoStar and Ten-X. This site groups it with Real Estate stocks.
Why does Costar Group have no margin of safety on this site?
This site's DCF values a company from its free cash flow, and that does not fit real-estate companies, which are valued on property income rather than on free cash flow. So CSGP gets no margin of safety; judge it on the other checks on this page, such as its filters, shareholder yield and ranking against its peers. The method is in the Intrinsic Value Calculator.
How many of this site's 8 value filters does Costar Group pass?
CSGP passes 3 of 8. It passes Price/Book < 8 (1.81), Price/Sales < 7 (4.05) and EPS Growth YoY > -5% (+831.5%). It misses Market Cap > $25B ($14.4B), Trailing P/E < 25 (195.55) and PEG Ratio < 1.5 (4.66). vs 50-day MA (±12%) and vs 200-day MA (±12%) were not evaluated, because the moving-average checks only run on stocks that clear the fundamentals first. The 8-filter list shows every stock that passes all of them.
Are Costar Group's reported earnings reliable?
This site's earnings-quality check rates CSGP Mixed · 3 watch. Beneish M-score −2.15 (grey zone), mostly from more assets of uncertain value (often acquisitions) · accruals −4.3% of assets · 252% of profit arrived as cash · stock comp 6.0% of revenue · share count +1.7% a year. From the latest 10-K (year to Dec 2025). Concerns: the Beneish M-score (on watch), stock-based compensation (on watch) and share dilution (on watch). The five checks are the Beneish M-score (manipulation risk), accruals, cash conversion, stock-based compensation and share dilution; the Earnings Quality Screener shows how each is graded.
Are Costar Group's insiders buying its shares?
Yes: 1 open-market insider purchase of Costar Group shares, worth about $54.0 million in total, was reported in SEC Form 4 filings in the 90 days up to this page's last update. Only open-market purchases count here, not option exercises or stock awards. See the Insider Buying Tracker.
When does Costar Group report earnings next?
Costar Group's next earnings report is expected on October 27, 2026 after the market closes, with analysts expecting earnings of $0.34 per share. Dates come from the Finnhub earnings calendar and can move. In its last 4 quarters it beat the estimate 4 times, by an average of +16.5%.
Where do these numbers come from?
- Financial statements: Costar Group's 10-K annual report for the year ended Dec 31, 2025, filed Feb 26, 2026 (filing index). Every earlier year in the 10-year financials comes from the company's older 10-K filings, all listed on SEC EDGAR.
- Prices and market data: quotes, P/E and analyst ratings from Finnhub; daily price history and the 52-week range from Twelve Data, both refreshed weekly. Short interest comes from FINRA, reported twice a month.
- How to check a figure: click any number in the card above to see its exact source, and read the Editorial Standards for every rule behind the checks.
About this Costar Group Inc analysis
This page shows every value-investing check the site runs on Costar Group Inc (CSGP) in one place: the 8 mechanical filters, the Buffett and Lynch checklists, a margin of safety from a disclosed DCF, earnings quality, shareholder yield and how it ranks against its sector peers. The numbers come from SEC filings and public market data, refreshed weekly, and the same rules apply to every stock on the stock list. See Editorial Standards for the sources and the rules, or run your own filters in the stock screener.