IRM Iron Mountain Incorporated
Iron Mountain Incorporated (IRM) Institutional Ownership
What the institutions did with IRM last quarter, from their 13F filings. Counting managers rather than shares is the point: a single index fund adding to a position tells you far less than four hundred separate managers all deciding to. Positions as reported for the quarter ended September 30, 2026.
Every manager below opens. Subscribers can see any firm's whole portfolio — every position, its weight, and what they bought, trimmed and exited last quarter.
Sign in or subscribeOwnership map
Each block is one manager, sized by shares held and colored by how much they moved the position last quarter. Green added, red cut, grey stood pat.
Largest holders
| Manager | Shares | % of reported |
|---|---|---|
| DIMENSIONAL FUND ADVISORS LP | 4.7M | 16.5% |
| PRINCIPAL FINANCIAL GROUP INC | 2.9M | 10.2% |
| Daiwa Securities Group Inc. | 1.9M | 6.9% |
| Bank of New York Mellon Corp | 1.6M | 5.6% |
| Pictet Asset Management Holding SA | 1.1M | 3.8% |
| Mitsubishi UFJ Asset Management Co., Ltd. | 1.0M | 3.7% |
| Sumitomo Mitsui Trust Group, Inc. | 847.7K | 3.0% |
| BARCLAYS PLC | 787.3K | 2.8% |
| Vontobel Holding Ltd. | 711.6K | 2.5% |
| Welch & Forbes LLC | 630.9K | 2.2% |
| Asset Management One Co., Ltd. | 556.2K | 2.0% |
| VIRGINIA RETIREMENT SYSTEMS ET Al | 441.8K | 1.6% |
| CITIGROUP INC | 390.7K | 1.4% |
| Thrivent Financial for Lutherans | 372.8K | 1.3% |
| ADELL HARRIMAN & CARPENTER INC | 318.8K | 1.1% |
| COMMONWEALTH OF PENNSYLVANIA PUBLIC SCHOOL EMPLS RETRMT SYS | 309.9K | 1.1% |
| Robeco Institutional Asset Management B.V. | 303.7K | 1.1% |
| Swedbank AB | 274.0K | 1.0% |
| Americana Partners, LLC | 243.7K | 0.9% |
| Border to Coast Pensions Partnership Ltd | 240.0K | 0.8% |
| Retirement Systems of Alabama | 225.5K | 0.8% |
| NEW YORK STATE TEACHERS RETIREMENT SYSTEM | 219.0K | 0.8% |
| DekaBank Deutsche Girozentrale | 210.3K | 0.7% |
| State of Alaska, Department of Revenue | 176.5K | 0.6% |
| Moran Wealth Management, LLC | 163.9K | 0.6% |
Largest changes
| Manager | Action | Previous | Current | Change |
|---|---|---|---|---|
| PRINCIPAL FINANCIAL GROUP INC | Reduced | 4.4M | 2.9M | -1.5M |
| Vontobel Holding Ltd. | Reduced | 1.9M | 711.6K | -1.2M |
| DekaBank Deutsche Girozentrale | Reduced | 1.1M | 210.3K | -912.2K |
| Pictet Asset Management Holding SA | Increased | 817.6K | 1.1M | +263.4K |
| Thrivent Financial for Lutherans | Increased | 165.5K | 372.8K | +207.2K |
| STRS OHIO | New | 0 | 129.9K | +129.9K |
| Cambridge Investment Research Advisors, Inc. | Reduced | 240.4K | 110.8K | -129.6K |
| Daiwa Securities Group Inc. | Increased | 1.9M | 1.9M | +80.1K |
| INTACT INVESTMENT MANAGEMENT INC. | Sold Out | 61.7K | 0 | -61.7K |
| Mitsubishi UFJ Asset Management Co., Ltd. | Increased | 982.6K | 1.0M | +58.4K |
| HOURGLASS CAPITAL, LLC | Reduced | 66.1K | 14.5K | -51.6K |
| Sumitomo Mitsui Trust Group, Inc. | Reduced | 896.6K | 847.7K | -48.9K |
| DIMENSIONAL FUND ADVISORS LP | Increased | 4.6M | 4.7M | +48.4K |
| Nippon Life Global Investors Americas, Inc. | Reduced | 111.5K | 65.6K | -45.9K |
| BARCLAYS PLC | Increased | 743.3K | 787.3K | +44.0K |
| Allspring Global Investments Holdings, LLC | Increased | 56.7K | 100.0K | +43.3K |
| Achmea Investment Management B.V. | New | 0 | 41.5K | +41.5K |
| Border to Coast Pensions Partnership Ltd | Reduced | 275.0K | 240.0K | -35.0K |
| Munich Reinsurance Co Stock Corp in Munich | Sold Out | 32.7K | 0 | -32.7K |
| SEB Asset Management AB | Increased | 75.9K | 108.1K | +32.2K |
| CITIGROUP INC | Reduced | 422.5K | 390.7K | -31.9K |
| KBC Group NV | Increased | 86.9K | 118.8K | +31.8K |
| Fideuram Asset Management (Ireland) dac | Reduced | 43.9K | 14.5K | -29.4K |
| ADAMS DIVERSIFIED EQUITY FUND, INC. | Increased | 102.9K | 129.5K | +26.6K |
| Jefferies Financial Group Inc. | New | 0 | 24.4K | +24.4K |
| COMMONWEALTH OF PENNSYLVANIA PUBLIC SCHOOL EMPLS RETRMT SYS | Increased | 286.4K | 309.9K | +23.5K |
| State of New Jersey Common Pension Fund D | Increased | 96.3K | 119.3K | +23.0K |
| Nepsis Inc. | Sold Out | 22.0K | 0 | -22.0K |
| Creative Planning | Increased | 139.9K | 159.5K | +19.6K |
| ELEVATUS WELATH MANAGEMENT | Reduced | 29.7K | 11.2K | -18.4K |
| WEALTH ENHANCEMENT ADVISORY SERVICES, LLC | Increased | 61.8K | 80.0K | +18.2K |
| Venture Visionary Partners LLC | Reduced | 34.4K | 16.7K | -17.7K |
| IFM Investors Pty Ltd | Increased | 113.9K | 131.3K | +17.5K |
| NEOS Investment Management LLC | Increased | 110.7K | 125.8K | +15.1K |
| PensionDanmark Pensionsforsikringsaktieselskab | Reduced | 68.5K | 55.0K | -13.5K |
| Oak Thistle LLC | New | 0 | 13.2K | +13.2K |
| Savant Capital, LLC | Increased | 10.1K | 23.2K | +13.1K |
| SIMPLEX TRADING, LLC | New | 0 | 13.1K | +13.1K |
| Ascentis Independent Advisors | New | 0 | 13.1K | +13.1K |
| Swedbank AB | Reduced | 287.1K | 274.0K | -13.1K |
| COMMONWEALTH EQUITY SERVICES, LLC | Reduced | 157.9K | 145.8K | -12.0K |
| Assenagon Asset Management S.A. | Reduced | 24.0K | 12.0K | -12.0K |
| Mirae Asset Global Investments Co., Ltd. | Increased | 68.8K | 79.8K | +11.0K |
| Kestra Advisory Services, LLC | Increased | 100.1K | 110.8K | +10.7K |
| Wellington Shields & Co., LLC | Sold Out | 10.6K | 0 | -10.6K |
| Smith Group Asset Management, LLC | Sold Out | 10.0K | 0 | -10.0K |
| CANTOR FITZGERALD INVESTMENT ADVISORS L.P. | New | 0 | 10.0K | +10.0K |
| AG2R LA MONDIALE GESTION D'ACTIFS | Reduced | 17.3K | 7.5K | -9.8K |
| MACKENZIE FINANCIAL CORP | Increased | 49.4K | 58.7K | +9.3K |
| M Holdings Securities, Inc. | New | 0 | 8.7K | +8.7K |
| Welch & Forbes LLC | Reduced | 639.3K | 630.9K | -8.4K |
| REGIONS FINANCIAL CORP | Reduced | 29.9K | 21.8K | -8.2K |
| HB Wealth Management, LLC | Increased | 15.6K | 23.3K | +7.7K |
| Machina Capital S.A.S. | Increased | 7.8K | 14.8K | +7.0K |
| ABN AMRO INVESTMENT SOLUTIONS | Increased | 18.8K | 25.7K | +6.9K |
| EXCHANGE TRADED CONCEPTS, LLC | Increased | 3.5K | 10.3K | +6.9K |
| SALEM INVESTMENT COUNSELORS INC | Reduced | 77.2K | 70.8K | -6.4K |
| Robeco Institutional Asset Management B.V. | Increased | 297.9K | 303.7K | +5.8K |
| Archer Investment Corp | Reduced | 11.6K | 5.8K | -5.8K |
| Jackson Creek Investment Advisors LLC | New | 0 | 5.7K | +5.7K |
13F filings are due 45 days after quarter end and cover long positions in U.S.-listed equities only, so this is a lagged and partial picture: shorts, bonds and foreign listings never appear. Options positions are excluded here rather than folded into the share counts. Political ownership is coming.