Iron MountainIRM
13F holders, Q2 2026 (June 30)1,173holders +83
141new positions
61sold out
10famous investors
$126.18avg. 13F price*
At the end of Q2 2026, 1,173 institutions reported holding Iron Mountain Inc. (IRM) in their 13F filings, up 83 from Q1 2026. 141 opened new positions and 61 sold out. The largest holders were BlackRock, Inc. ($4.2B), Vanguard Portfolio Management LLC ($3.2B) and Vanguard Capital Management LLC ($2.4B). 10 famous investors held it, including Cliff Asness (0.1% of AQR Capital Management's portfolio), Ron Baron (0.1% of Baron Capital (BAMCO)'s portfolio) and Paul Tudor Jones (0.0% of Tudor Investment Corporation's portfolio).
- Company
- Iron Mountain Inc.
- Filed as
- IRON MTN INC DEL (Q2 2026)
- Sector
- Real Estate
- CUSIP
- 46284V101
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q1 2026 → Q2 2026
| Institutions | Total Value | |
|---|---|---|
| New Positions | 141 | $251.5M |
| Exits | 61 | $175.9M |
All 13F filers, Q1 2026 → Q2 2026: 14,636,946 shares bought and 15,081,776 shares sold, net −444,830 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 1,173 holders
| BlackRock, Inc. | 0.06% | Add +1.7% | 33,570,910 | $4.2B |
| Vanguard Portfolio Management LLC | 0.15% | Add +2.2% | 25,568,944 | $3.2B |
| Vanguard Capital Management LLC | 0.05% | Add +1.0% | 18,953,705 | $2.4B |
| State Street Corp. | 0.07% | Add +0.5% | 17,634,044 | $2.2B |
| Cohen & Steers, Inc. | 2.40% | Reduce -25.7% | 12,019,735 | $1.5B |
| Geode Capital Management, LLC | 0.06% | Add +1.9% | 8,649,249 | $1.1B |
| FMR LLC | 0.04% | Add +5.2% | 7,872,365 | $994.4M |
| Dimensional Fund Advisors LP | 0.11% | Add +1.6% | 4,625,684 | $584.3M |
| Morgan Stanley | 0.03% | Reduce -4.8% | 4,426,922 | $559.2M |
| Principal Financial Group Inc. | 0.27% | Reduce -4.2% | 4,373,424 | $552.4M |
| Charles Schwab Investment Management Inc. | 0.07% | Add +6.2% | 4,263,487 | $538.5M |
| Northern Trust Corp. | 0.06% | Add +1.8% | 4,222,967 | $533.4M |
| Norges Bank | 0.05% | — | 4,214,697 | $532.4M |
| Invesco Ltd. | 0.04% | Add +3.7% | 4,065,649 | $513.5M |
| Legal & General Group Plc | 0.09% | Add +3.5% | 3,244,741 | $409.8M |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | 0.07% | Add +29674.0% | 3,193,560 | $403.4M |
| Deutsche Bank AG | 0.11% | Reduce -1.4% | 3,049,079 | $385.1M |
| Goldman Sachs Group Inc. | 0.04% | Add +27.3% | 2,822,732 | $356.5M |
| Centersquare Investment Management LLC | 2.51% | Add +0.6% | 2,323,974 | $293.5M |
| JPMorgan Chase & Co. | 0.02% | Add +4.2% | 2,212,137 | $287.5M |
| Nuveen, LLC | 0.07% | Add +7.3% | 2,218,771 | $280.3M |
| AQR Capital Management | 0.09% | Add +15.2% | 2,127,095 | $266.5M |
| Prudential Financial Inc. | 0.27% | Reduce -18.3% | 1,974,079 | $249.3M |
| Vontobel Holding Ltd. | 0.81% | Reduce -9.3% | 1,919,656 | $242.5M |
| Daiwa Securities Group Inc. | 0.53% | Reduce -40.1% | 1,861,547 | $235.1M |
| Ameriprise Financial Inc. | 0.04% | Reduce -9.9% | 1,668,337 | $210.9M |
| Vanguard Fiduciary Trust Co. | 0.05% | Add +0.3% | 1,658,635 | $209.5M |
| Royal Bank of Canada | 0.04% | Add +16.3% | 1,640,511 | $207.2M |
| Bank of New York Mellon Corp | 0.03% | Reduce -1.5% | 1,600,078 | $202.1M |
| Duff & Phelps Investment Management Co. | 1.73% | Reduce -7.6% | 1,455,435 | $183.8M |
| Russell Investments Group, Ltd. | 0.16% | Reduce -3.5% | 1,403,623 | $177.4M |
| HSBC Holdings PLC | 0.08% | Add +5.9% | 1,347,871 | $170.3M |
| Contour Asset Management LLC | 3.81% | Reduce -11.8% | 1,274,684 | $161.0M |
| Capital World Investors | 0.02% | Reduce -34.8% | 1,217,169 | $153.7M |
| Amundi | 0.04% | Add +7.0% | 1,168,430 | $147.6M |
| American Century Companies Inc. | 0.06% | Add +41.5% | 1,154,487 | $145.8M |
| Bank of America Corp. | 0.01% | Reduce -20.1% | 1,118,827 | $141.3M |
| CBRE Investment Management Listed Real Assets LLC | 1.89% | Reduce -13.3% | 1,072,881 | $135.5M |
| Mitsubishi UFJ Asset Management Co., Ltd. | 0.07% | Add +8.2% | 982,596 | $124.1M |
| UBS Group AG | 0.02% | Add +14.2% | 915,101 | $115.6M |
| DekaBank Deutsche Girozentrale | 0.19% | No change | 1,122,500 | $114.2M |
| Sumitomo Mitsui Trust Group, Inc. | 0.06% | Reduce -4.0% | 896,560 | $113.2M |
| Swiss National Bank | 0.06% | Reduce -3.3% | 839,061 | $106.0M |
| Pictet Asset Management Holding SA | 0.10% | Reduce -5.5% | 817,622 | $103.3M |
| CIBC Bancorp USA Inc. | 0.12% | Reduce -6.2% | 777,480 | $98.2M |
| Barclays PLC | 0.03% | Add +10.3% | 743,343 | $93.9M |
| Sei Investments Co. | 0.08% | Reduce -28.4% | 697,737 | $88.1M |
| Aberdeen Group plc | 0.12% | Add +86.3% | 691,514 | $87.3M |
| APG Asset Management US Inc. | 0.60% | No change | 703,912 | $85.8M |
| PGGM Investments | 2.10% | Reduce -50.7% | 675,093 | $85.3M |
| Wells Fargo & Company | 0.01% | Add +0.6% | 662,157 | $83.6M |
| BNP Paribas Financial Markets | 0.04% | Add +27.5% | 648,227 | $81.9M |
| Vanguard Global Advisers, LLC | 0.04% | Reduce -0.9% | 641,901 | $81.1M |
| LPL Financial LLC | 0.02% | Add +3.1% | 640,383 | $80.9M |
| Welch & Forbes LLC | 0.98% | Reduce -1.9% | 639,322 | $80.8M |
| T. Rowe Price Associates Inc. | 0.01% | Add +5.5% | 634,613 | $80.2M |
| Universal- Beteiligungs- und Servicegesellschaft mbH | 0.12% | Add +3.5% | 610,889 | $77.1M |
| Quantinno Capital Management LP | 0.09% | Add +83.4% | 590,647 | $74.6M |
| Nomura Asset Management Co. Ltd. | 0.16% | Add +4.5% | 588,384 | $74.3M |
| Rhumbline Advisers | 0.05% | Reduce -0.9% | 573,267 | $72.4M |
| VANGUARD ASSET MANAGEMENT, Ltd | 0.05% | Add +12.6% | 568,845 | $71.9M |
| Raymond James Financial Inc. | 0.02% | Add +90.3% | 561,539 | $70.9M |
| Asset Management One Co., Ltd. | 0.18% | Add +1.3% | 554,607 | $70.1M |
| California Public Employees Retirement System | 0.04% | Add +10.2% | 553,872 | $70.0M |
| Nomura Asset Management International Inc. | 0.11% | Reduce -5.9% | 552,190 | $69.7M |
| Worldquant Millennium Advisors LLC | 0.23% | Reduce -2.0% | 537,162 | $67.8M |
| Adage Capital Partners Gp, L.L.C. | 0.09% | Reduce -9.3% | 535,152 | $67.6M |
| Wellington Management Group LLP | 0.01% | Add +47.4% | 512,906 | $64.8M |
| Clark Capital Management Group, Inc. | 0.33% | Add +1.8% | 476,766 | $60.2M |
| DigitalBridge Group, Inc. | 3.48% | Reduce -9.3% | 457,126 | $57.7M |
| Alliancebernstein L.P. | 0.02% | Reduce -0.5% | 562,711 | $57.5M |
| National Pension Service | 0.04% | Add +5.9% | 454,815 | $57.4M |
| Bank of Montreal | 0.02% | Add +11.8% | 453,715 | $57.3M |
| Healthcare of Ontario Pension Plan Trust Fund | 0.08% | Add +106.6% | 443,901 | $56.1M |
| VIRGINIA RETIREMENT SYSTEMS ET Al | 0.33% | Add +0.4% | 441,803 | $55.8M |
| California State Teachers Retirement System | 0.05% | Add +2.8% | 434,529 | $54.9M |
| Public Employees Retirement System of Ohio | 0.16% | Reduce -0.3% | 422,586 | $53.4M |
| Citigroup Inc. | 0.02% | Add +33.9% | 422,524 | $53.4M |
| Voloridge Investment Management, LLC | 0.22% | New | 412,748 | $52.1M |
| Jane Street Group, LLC | 0.03% | Reduce -44.0% | 396,541 | $50.1M |
| Rockefeller Capital Management L.P. | 0.08% | Add +0.6% | 391,620 | $49.5M |
| Heitman Real Estate Securities LLC | 2.90% | Add +37.8% | 357,721 | $45.2M |
| CANADA LIFE ASSURANCE Co | 0.07% | Add +5.9% | 355,692 | $44.8M |
| Vanguard Investments Australia, Ltd. | 0.11% | Add +1.2% | 347,312 | $43.9M |
| Citadel Advisors | 0.03% | Reduce -8.5% | 343,168 | $43.3M |
| Adelante Capital Management LLC | 2.70% | Reduce -8.8% | 325,641 | $41.1M |
| Adell Harriman & Carpenter Inc. | 2.05% | Add +0.2% | 316,465 | $40.0M |
| Baron Capital (BAMCO) | 0.06% | Reduce -40.9% | 310,721 | $39.2M |
| Robeco Institutional Asset Management B.V. | 0.05% | Add +1940.0% | 297,899 | $37.6M |
| Teacher Retirement System of Texas | 0.10% | Reduce -24.6% | 297,427 | $37.6M |
| Marble Harbor Investment Counsel, LLC | 3.79% | Reduce -1.6% | 295,533 | $37.3M |
| Acadian Asset Management LLC | 0.04% | Add +72.9% | 292,064 | $36.9M |
| Neuberger Berman Group LLC | 0.02% | Reduce -19.5% | 290,384 | $36.7M |
| Swedbank AB | 0.03% | Add +10.3% | 287,064 | $36.3M |
| Commonwealth of Pennsylvania Public School Empls Retrmt SYS | 0.18% | Add +41.6% | 286,428 | $36.2M |
| SG Americas Securities, LLC | 0.02% | New | 284,584 | $35.9M |
| Macquarie Group Ltd. | 0.15% | Add +2.0% | 275,969 | $34.9M |
| Border to Coast Pensions Partnership Ltd | 0.51% | Reduce -41.5% | 275,000 | $34.7M |
| Victory Capital Management Inc. | 0.02% | Add +12.6% | 268,209 | $33.9M |
| Apollo Management Holdings, L.P. | 0.55% | No change | 265,539 | $33.5M |
"% of holder's portfolio" is IRM's weight in each manager's 13F, not the share of Iron Mountain Inc. the manager owns.