American Tower Corp /ma/ vs Simon Property Group (AMT vs SPG)
Side by side from their SEC filings: revenue, margins, growth, returns and valuation, plus short interest, insider activity and institutional ownership.
American Tower Corp /ma/ is the larger company by revenue ($10.6B vs $6.4B) and market value ($82.0B vs $80.4B). Simon Property Group has grown revenue faster over the last 4 fiscal years (+24.4% cumulative vs +13.8%). Simon Property Group runs the higher operating margin (49.9% vs 45.5%). Simon Property Group trades at the lower trailing P/E (15.0x vs 24.1x).
About American Tower Corp /ma/
American Tower Corp is a global real estate investment trust that owns, operates, and develops multitenant communications real estate. The company leases space on its communications sites, including towers and distributed antenna system networks, to wireless service providers, broadcasters, government agencies, and other tenants. It also operates data centers and provides tower-related services such as site application, zoning, permitting, and construction management primarily in the United States.
About Simon Property Group
Simon Property Group Inc. operates as a real estate investment trust specializing in retail real estate. The company owns and manages shopping malls, premium outlet centers, and other retail properties across the United States. It serves retailers and consumers by providing commercial spaces for retail businesses.
Head to head (AMT FY2025 vs SPG FY2025)
| Metric | AMTFY2025 | SPGFY2025 |
|---|---|---|
| Revenue | $10.64B | $6.36B |
| Revenue growth (YoY) | 5.1% | 6.7% |
| Gross margin | — | — |
| Operating margin | 45.5% | 49.9% |
| Net margin | 24.7% | 84.3% |
| Net income | $2.63B | $5.36B |
| Diluted EPS | $5.40 | $14.17 |
| FCF margin | 35.5% | 50.3% |
| ROE | 25.4% | 82.9% |
| Long-term debt / equity | 3.27× | 4.39× |
| Market cap | $82.02B | $80.43B |
| P/E | 24.1× | 15.0× |
Fundamentals are from each company’s SEC filings (AMT FY2025, SPG FY2025). ROE is net income over fiscal-year-end equity; long-term debt / equity counts non-current term debt only. P/E and market cap are derived from stored market prices, last retrieved on a rolling basis and typically within the past week.
Five-year trend (as reported)
| Revenue | FY2021 | FY2022 | FY2023 | FY2024 | FY2025 |
|---|---|---|---|---|---|
| AMT | $9.36B | $9.65B | $10.01B | $10.13B | $10.64B |
| SPG | $5.12B | $5.29B | $5.66B | $5.96B | $6.36B |
Peer standing
Where each company ranks among the 165 REITs, on the same scale. Each figure is ranked only against peers that report it. Percentiles describe position in the distribution, not a rating.
| Metric | AMT | SPG |
|---|---|---|
| Operating margin | 45.5%69th percentile of 81 | 49.9%78th percentile of 81 |
| Net margin | 24.7%70th percentile of 156 | 84.3%99th percentile of 156 |
| FCF margin | 35.5%73rd percentile of 27 | 50.3%88th percentile of 27 |
| Revenue growth (YoY) | +5.1%59th percentile of 161 | +6.7%66th percentile of 161 |
| ROE | 25.4%96th percentile of 142 | 82.9%Highest of 142 |
| P/E | 24.1×39th percentile of 109 | 15.0×13th percentile of 109 |
| Long-term debt / equity | 3.27×89th percentile of 100 | 4.39×92nd percentile of 100 |
| Short interest (days to cover) | 2.97d25th percentile of 152 | 5.83d69th percentile of 152 |
Short interest
| FINRA settlement data | AMT | SPG |
|---|---|---|
| Shares sold short | 7.0M | 8.7M |
| Change vs prior settlement | -7.5% | -10.8% |
| Days to cover | 2.97 | 5.83 |
| As of settlement | 2026-08-14 | 2026-08-14 |
Source: FINRA Consolidated Short Interest. FINRA is the owner and source of the FINRA-supplied data; republishing or redistributing it is not permitted. Not presented as a percentage of float. No FINRA endorsement of this product is implied.
Insider activity (last 90 days)
| Form 4 activity (codes P/S) | AMT | SPG |
|---|---|---|
| Buys | 1 ($500,733) | 28 ($533,052) |
| Sells | 3 ($1.2M) | 0 |
Non-derivative purchases (code P) and sales (code S) reported on SEC Form 4, which may be open-market or private (grants, exercises and tax withholding excluded). For context, about 15% of covered companies saw any reported insider purchase (code P) in a 90-day window.
Held by the same investors
6 tracked 13F managers hold both American Tower Corp /ma/ and Simon Property Group as of their latest quarterly filings: AQR Capital Management, Citadel Advisors, D. E. Shaw, Gotham Asset Management, Millennium Management, Two Sigma Investments. See which superinvestors hold your own portfolio with the smart money checker.
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Data sourced from SEC EDGAR. Figures are as-reported and may be unaudited or restated; verify against the source filings before relying on them. Comparisons are descriptive (higher or lower on a reported figure), not a rating or a recommendation. Informational only. Not investment advice.