IRM
Iron Mountain Incorporated · Real Estate · REIT - Specialty
Momentum inputs (comparable managers):
holder breadth +30.0% ·
share flow +0.1% ·
net new positions +20.0%
— formula
Broad accumulation — rising shares across more holders
All ownership figures: tracked 13F managers only, common-stock positions, reporting period Q4 2024
| Quarter | Holders | Δ | Shares | Reported value | New | Exits |
|---|---|---|---|---|---|---|
| Q2 2026 | 159 | 0 | 181.12M | $22.88B | +6 | −5 |
| Q1 2026 | 161 | +4 | 173.50M | $17.71B | +10 | −7 |
| Q4 2025 | 156 | +1 | 203.32M | $16.87B | +2 | — |
| Q3 2025 | 19 | 0 | 127.27M | $12.98B | — | −1 |
| Q2 2025 | 17 | -2 | 121.35M | $12.46B | — | −2 |
| Q1 2025 | 16 | 0 | 38.25M | $3.31B | +2 | −2 |
| Q4 2024 | 16 | +4 | 36.36M | $3.83B | +4 | — |
| Q3 2024 | 11 | +1 | 19.71M | $2.34B | +2 | −1 |
| Q2 2024 | 10 | — | 19.98M | $1.79B | — | — |
| # | Manager | Shares | Δ shares | Value | Their weight | Held | ||
|---|---|---|---|---|---|---|---|---|
| 1 | State Street Global Advisors ✦ (passive) | 16.62M | — | $1.76B | 0.1% | n/c | 1 | SEC ↗ |
| 2 | Geode Capital Management ✦ (passive) | 7.91M | -4.2% | $832.88M | 0.1% | ▼ Trim | 3 | SEC ↗ |
| 3 | Geode Capital Management ✦ (passive) | 7.91M | -4.2% | $832.88M | 0.1% | ▼ Trim | 3 | SEC ↗ |
| 4 | Capital World Investors ✦ | 3.82M | -7.2% | $401.25M | 0.1% | ▼ Trim | 3 | SEC ↗ |
| 5 | Norges Bank ✦ (passive) | 3.31M | +1.0% | $348.25M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 6 | Wellington Management ✦ | 1.55M | -35.3% | $162.68M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 7 | Wellington Management ✦ | 1.55M | -35.3% | $162.68M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 8 | Wellington Management ✦ | 1.55M | -35.3% | $162.68M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 9 | Wellington Management ✦ | 1.55M | -35.3% | $162.68M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 10 | Point72 Asset Management ✦ | 1.20M | +439.8% | $126.20M | 0.4% | ▲ Add | 2 | SEC ↗ |
| 11 | T. Rowe Price ✦ | 877.24K | +7.0% | $92.21M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 12 | T. Rowe Price ✦ | 877.24K | +7.0% | $92.21M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 13 | Citadel Advisors ✦ | 604.34K | +817.5% | $63.52M | 0.1% | ▲ Add | 2 | SEC ↗ |
| 14 | Citadel Advisors ✦ | 604.34K | +817.5% | $63.52M | 0.1% | ▲ Add | 2 | SEC ↗ |
| 15 | AQR Capital Management ✦ | 203.86K | +24.5% | $21.23M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 16 | AQR Capital Management ✦ | 203.86K | +24.5% | $21.23M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 17 | AQR Capital Management ✦ | 203.86K | +24.5% | $21.23M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 18 | Adage Capital Partners ✦ | 114.15K | -35.3% | $12.00M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 19 | Gotham Asset Management ✦ | 86.56K | +6.3% | $9.10M | 0.1% | ▲ Add | 3 | SEC ↗ |
| 20 | Millennium Management ✦ | 29.21K | -77.4% | $3.07M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 21 | Marshall Wace ✦ | 18.37K | New | $1.93M | 0.0% | New | 1 | SEC ↗ |
| 22 | D. E. Shaw & Co. ✦ | 10.70K | New | $1.12M | 0.0% | New | 1 | SEC ↗ |
| 23 | D. E. Shaw & Co. ✦ | 10.70K | New | $1.12M | 0.0% | New | 1 | SEC ↗ |
| 24 | Fisher Asset Management ✦ | 5.59K | New | $587,337 | 0.0% | New | 1 | SEC ↗ |
| 25 | Bridgewater Associates ✦ | 2.07K | New | $217,998 | 0.0% | New | 1 | SEC ↗ |
“Their weight” = the position's share of that manager's reported 13F equity value — the conviction measure. ✦ = curated manager.
New buyers
| Marshall Wace | $1.93M | 0.0% |
| D. E. Shaw & Co. | $1.12M | 0.0% |
| D. E. Shaw & Co. | $1.12M | 0.0% |
| Fisher Asset Management | $587,337 | 0.0% |
| Bridgewater Associates | $217,998 | 0.0% |
Exited
| No tracked exits this quarter. |
Full-market context: across ALL 13F filers (SEC structured data, Q1 2026): 1,078 holders, 250.54M shares, $23.29B reported. This is a different, older period than the tracked-universe figures above and the two are never mixed.
What else this security's tracked holders most often hold — shared-ownership counts, not fundamental relationships.
Open-market purchases (P)
No open-market insider purchases in our coverage window.
Open-market sales (S)
Officer, Director · 18.78K sh · $2.27M
Officer, Director · 16.79K sh · $2.05M
Officer, Director · 2.91K sh · $357,080
Officer · 6.00K sh · $736,200
Officer · 5.00K sh · $635,650
Officer · 6.84K sh · $869,442
Awards, exercises and tax withholding are never counted as buys or sales here. Methodology