IRM vs SPG
Iron Mountain Inc (IRM) and Simon Property Group Inc. (SPG) are both filed with the SEC under Real Estate Investment Trusts. SPG is 1.9× IRM's size by market cap ($70.1B against $36.5B); IRM trades at the higher fiscal-year P/E (250.4× against 15.2×); SPG reports the higher net margin (84.3% against 2.2%); IRM grew sales faster over three years (+10.6% against +6.3%); and over the past year IRM returned +31.1% against SPG's +24.0%.
| IRM | SPG | |
|---|---|---|
| Last close | $117.40 | $214.56 |
| Market cap | $36.5B | $70.1B |
| P/E (FY) | 250.4× | 15.2× |
| P/S | 5.3× | 11.0× |
| EV/EBITDA | 24.1× | 21.2× |
| Operating margin | 16.9% | 49.9% |
| Net margin | 2.2% | 84.3% |
| Return on equity | — | 131.6% |
| Sales growth (3y) | +10.6% | +6.3% |
| EPS growth (3y) | -36.3% | +29.5% |
| Dividend yield | 2.5% | — |
| 1-year return | +31.1% | +24.0% |
Screener snapshot — prices as of 2026-08-28. Each side's last close is the most recent session the snapshot holds for that company, which can be an earlier one, and its 1-year return is measured to that close. Market caps struck on 2026-08-27. Last close, market cap and the 1-year return are price figures; every other row is computed over the company's latest filed fiscal year — FY2025 (ended 2025-12-31) for both. A return on equity past ±100% — SPG at 131.6% — divides earnings by an average filed equity base smaller in magnitude than the earnings themselves; the two columns are not on one scale. — not published for this company. A ratio goes unpublished for more than one reason: a component the calculation needs is not on file, the filing does not tag the line it is read from, or the calculation is not defined on the filed basis — EV/EBITDA is not printed on non-positive EBITDA, and return on equity is not computed on a zero or negative equity base.
Who holds them, and who has traded them
| IRM | SPG | |
|---|---|---|
| Institutional holders (13F) | 1,079 | 1,296 |
| Insider buyers − sellers (180d) | -5 | +5 |
| Congressional trades disclosed (180d) | 0 | 2 |
| Executive-branch officials on file — trades disclosed (180d) | 3 | 1 |
Counts only. The congressional figures count transactions dated in the trailing 180 days and disclosed in STOCK Act periodic transaction reports; amounts are filed as ranges and are never summed. The executive-branch figures count the same window of transactions, and they are scoped to one roster. The officials OGE posts for direct download. Insider buyers − sellers counts distinct people filing open-market Form 4 purchases minus distinct people filing open-market sales over the trailing 180 days, capped at ±5.
IRM vs SPG: common questions
- Is IRM bigger than SPG?
- SPG carries the larger market cap — $70.1B against $36.5B, both struck on 2026-08-27.
- Which trades at a higher P/E, IRM or SPG?
- IRM, at a fiscal-year 250.4× against 15.2× for SPG. Both are price ÷ latest full-year diluted earnings per share, not a trailing-twelve-month P/E.
- How have IRM and SPG performed over the past year?
- IRM returned +31.1% and SPG +24.0%, measured on the trailing calendar year to the last close.
- How many institutions hold IRM and SPG?
- 1,079 13F filers report a position in IRM and 1,296 in SPG, on the latest quarter in the panel.
- Are IRM and SPG in the same industry?
- Both are filed with the SEC under Real Estate Investment Trusts, which is the classification this pairing is built on.
IRM overview → · SPG overview → · IRM institutional ownership → · SPG institutional ownership → · Congress and SPG → · Executive branch and IRM → · Executive branch and SPG →
More in Real Estate Investment Trusts: AMT vs DLR · AMT vs EQIX · AMT vs IRM · AMT vs PLD
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Source: SPZCO — https://spzco.com/vs/irm-vs-spg