Iron MountainIRM
13F holders, Q4 2025 (December 31)1,011holders −5
71new positions
105sold out
8famous investors
$83.00avg. 13F price*
At the end of Q4 2025, 1,011 institutions reported holding Iron Mountain Inc. (IRM) in their 13F filings, down 5 from Q3 2025. 71 opened new positions and 105 sold out. The largest holders were Vanguard Group Inc. ($3.9B), BlackRock, Inc. ($2.7B) and Cohen & Steers, Inc. ($1.6B). 8 famous investors held it, including Steve Cohen (0.1% of Point72 Asset Management's portfolio), Ken Griffin (0.1% of Citadel Advisors's portfolio) and Cliff Asness (0.0% of AQR Capital Management's portfolio).
- Company
- Iron Mountain Inc.
- Filed as
- IRON MTN INC DEL (Q4 2025)
- Sector
- Real Estate
- CUSIP
- 46284V101
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q3 2025 → Q4 2025
| Institutions | Total Value | |
|---|---|---|
| New Positions | 71 | $119.2M |
| Exits | 105 | $183.7M |
All 13F filers, Q3 2025 → Q4 2025: 16,048,267 shares bought and 13,797,225 shares sold, net +2,251,042 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 1,011 holders
| Vanguard Group Inc. | 0.06% | Reduce -1.3% | 46,627,483 | $3.9B |
| BlackRock, Inc. | 0.05% | Add +3.8% | 32,919,658 | $2.7B |
| Cohen & Steers, Inc. | 2.84% | Add +20.0% | 18,903,716 | $1.6B |
| State Street Corp. | 0.05% | Reduce -1.4% | 16,888,798 | $1.4B |
| Geode Capital Management, LLC | 0.04% | Add +1.3% | 8,292,653 | $685.4M |
| FMR LLC | 0.03% | Add +1.6% | 7,984,304 | $662.3M |
| Norges Bank | 0.04% | — | 4,447,133 | $368.9M |
| Dimensional Fund Advisors LP | 0.08% | Add +1.9% | 4,429,359 | $367.4M |
| Invesco Ltd. | 0.03% | Reduce -12.8% | 4,417,367 | $366.4M |
| Principal Financial Group Inc. | 0.18% | Add +66.5% | 4,207,596 | $349.0M |
| Northern Trust Corp. | 0.04% | Add +3.0% | 4,152,569 | $344.5M |
| Charles Schwab Investment Management Inc. | 0.05% | Add +5.6% | 3,880,275 | $321.9M |
| Daiwa Securities Group Inc. | 0.99% | Add +16.0% | 3,654,086 | $303.1M |
| Morgan Stanley | 0.02% | Reduce -0.3% | 3,598,973 | $298.5M |
| Legal & General Group Plc | 0.06% | Add +4.4% | 3,356,420 | $278.4M |
| Contour Asset Management LLC | 5.48% | Reduce -10.5% | 2,832,182 | $234.9M |
| Centersquare Investment Management LLC | 2.15% | Add +4.7% | 2,631,453 | $218.3M |
| Deutsche Bank AG | 0.07% | Reduce -12.1% | 2,541,992 | $210.9M |
| Prudential Financial Inc. | 0.23% | Add +9.3% | 2,310,481 | $191.7M |
| Pictet Asset Management Holding SA | 0.18% | Reduce -6.8% | 2,295,965 | $190.4M |
| Nuveen, LLC | 0.05% | Reduce -0.7% | 2,127,931 | $176.5M |
| Capital World Investors | 0.02% | No change | 2,117,169 | $175.6M |
| JPMorgan Chase & Co. | 0.01% | Reduce -6.3% | 1,927,935 | $159.9M |
| Ameriprise Financial Inc. | 0.03% | Add +2.3% | 1,744,405 | $142.5M |
| Vontobel Holding Ltd. | 0.46% | Add +56.6% | 1,689,246 | $140.1M |
| Bank of New York Mellon Corp | 0.02% | Add +1.2% | 1,685,978 | $139.9M |
| PGGM Investments | 2.18% | Reduce -1.6% | 1,657,159 | $137.5M |
| Duff & Phelps Investment Management Co. | 1.49% | Reduce -3.8% | 1,580,452 | $131.1M |
| Goldman Sachs Group Inc. | 0.02% | Add +12.6% | 1,525,240 | $126.5M |
| Bank of America Corp. | 0.01% | Add +23.0% | 1,510,345 | $125.3M |
| CBRE Investment Management Listed Real Assets LLC | 1.77% | Add +13.9% | 1,446,597 | $120.0M |
| Russell Investments Group, Ltd. | 0.13% | Reduce -17.6% | 1,405,760 | $116.6M |
| Amundi | 0.03% | Add +22.9% | 1,333,693 | $110.6M |
| Royal Bank of Canada | 0.02% | Reduce -44.1% | 1,285,871 | $106.7M |
| DekaBank Deutsche Girozentrale | 0.17% | No change | 1,122,500 | $95.8M |
| Citadel Advisors | 0.06% | Add +1726.3% | 1,119,371 | $92.9M |
| HSBC Holdings PLC | 0.05% | Add +10.9% | 1,055,775 | $87.6M |
| Sei Investments Co. | 0.08% | Add +17.4% | 1,024,664 | $85.0M |
| AQR Capital Management | 0.04% | Add +101.8% | 923,196 | $76.6M |
| Sumitomo Mitsui Trust Group, Inc. | 0.04% | Reduce -3.0% | 906,888 | $75.2M |
| Mitsubishi UFJ Asset Management Co., Ltd. | 0.05% | Add +4.6% | 839,566 | $69.9M |
| Swiss National Bank | 0.04% | Reduce -4.9% | 809,261 | $67.1M |
| UBS Group AG | 0.01% | Reduce -44.6% | 795,908 | $66.0M |
| Point72 Asset Management | 0.11% | Reduce -39.0% | 790,504 | $65.6M |
| Barclays PLC | 0.02% | Reduce -1.5% | 728,857 | $60.5M |
| CIBC Private Wealth Group LLC | 0.10% | Reduce -6.0% | 677,651 | $56.2M |
| Adage Capital Partners Gp, L.L.C. | 0.08% | Add +18.7% | 656,852 | $54.5M |
| Welch & Forbes LLC | 0.66% | Reduce -0.4% | 656,364 | $54.4M |
| Wells Fargo & Company | 0.01% | Reduce -0.1% | 637,272 | $52.9M |
| LPL Financial LLC | 0.01% | Reduce -10.5% | 634,799 | $52.7M |
| Epoch Investment Partners, Inc. | 0.30% | Reduce -3.2% | 629,854 | $52.2M |
| Universal- Beteiligungs- und Servicegesellschaft mbH | 0.09% | Add +25.7% | 625,444 | $52.0M |
| T. Rowe Price Associates Inc. | 0.01% | Add +1.9% | 606,859 | $50.3M |
| Rhumbline Advisers | 0.04% | Reduce -1.0% | 590,540 | $49.0M |
| APG Asset Management US Inc. | 0.38% | No change | 582,174 | $48.3M |
| BNP Paribas Financial Markets | 0.03% | Add +6.8% | 562,253 | $46.6M |
| Asset Management One Co., Ltd. | 0.13% | Add +0.8% | 555,974 | $45.9M |
| Alliancebernstein L.P. | 0.01% | Reduce -2.0% | 544,810 | $45.2M |
| Nomura Asset Management Co. Ltd. | 0.11% | Add +2.9% | 544,483 | $45.2M |
| California Public Employees Retirement System | 0.02% | Add +0.0% | 513,555 | $42.6M |
| National Pension Service | 0.03% | Add +2.7% | 509,020 | $42.2M |
| Border to Coast Pensions Partnership Ltd | 0.72% | Add +4.2% | 500,000 | $41.6M |
| DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main | 0.04% | Reduce -3.7% | 495,760 | $41.1M |
| Heitman Real Estate Securities LLC | 2.86% | Add +3.4% | 490,548 | $40.7M |
| Millennium Management | 0.03% | Add +0.7% | 489,014 | $40.6M |
| Bank of Montreal | 0.01% | Add +9.6% | 436,345 | $36.2M |
| California State Teachers Retirement System | 0.04% | Reduce -1.5% | 434,105 | $36.0M |
| Neuberger Berman Group LLC | 0.03% | Add +3.6% | 431,386 | $35.8M |
| STRS Ohio | 0.13% | Add +60.8% | 414,128 | $34.4M |
| Rockefeller Capital Management L.P. | 0.06% | Reduce -0.8% | 403,992 | $33.6M |
| American Century Companies Inc. | 0.02% | Reduce -28.3% | 395,893 | $32.8M |
| Raymond James Financial Inc. | 0.01% | Reduce -3.7% | 366,309 | $30.4M |
| Aberdeen Group plc | 0.05% | Reduce -4.6% | 364,889 | $30.3M |
| Adelante Capital Management LLC | 1.90% | Reduce -12.2% | 339,227 | $28.1M |
| CANADA LIFE ASSURANCE Co | 0.05% | Reduce -24.3% | 336,935 | $27.9M |
| Teacher Retirement System of Texas | 0.10% | Add +764.4% | 333,971 | $27.7M |
| Citigroup Inc. | 0.02% | Reduce -24.1% | 318,601 | $26.4M |
| Adell Harriman & Carpenter Inc. | 1.56% | Reduce -3.6% | 314,617 | $26.1M |
| Marble Harbor Investment Counsel, LLC | 2.78% | Reduce -3.5% | 314,020 | $26.0M |
| Macquarie Group Ltd. | 0.11% | Add +2.2% | 292,992 | $24.3M |
| Two Sigma Investments, LP | 0.04% | New | 290,160 | $24.1M |
| Swedbank AB | 0.02% | No change | 284,858 | $23.6M |
| Apollo Management Holdings, L.P. | 0.26% | New | 265,539 | $22.0M |
| State Board of Administration of Florida Retirement System | 0.04% | Reduce -3.0% | 262,515 | $21.8M |
| Aviva PLC | 0.04% | Add +5.6% | 256,125 | $21.2M |
| Captrust Financial Advisors | 0.04% | Reduce -66.8% | 255,142 | $21.2M |
| Cetera Investment Advisers | 0.02% | Reduce -2.3% | 248,597 | $20.6M |
| Americana Partners, LLC | 0.55% | New | 241,349 | $20.0M |
| Blair William & Co. | 0.05% | Reduce -25.2% | 238,285 | $19.8M |
| Brookstone Capital Management | 0.22% | Add +13.7% | 235,933 | $19.6M |
| Retirement Systems of Alabama | 0.06% | Reduce -1.2% | 228,071 | $18.9M |
| New York State Teachers Retirement System | 0.04% | Add +0.0% | 227,876 | $18.9M |
| Stifel Financial Corp. | 0.02% | Add +4.2% | 227,234 | $18.8M |
| Pacer Advisors, Inc. | 0.05% | Reduce -3.4% | 223,367 | $18.5M |
| Focus Partners Wealth | 0.02% | Add +68.2% | 217,915 | $18.3M |
| Regions Financial Corp. | 0.11% | Reduce -14.8% | 214,642 | $17.8M |
| Corient Private Wealth LP | 0.02% | Add +4.3% | 211,327 | $17.5M |
| Schonfeld Strategic Advisors LLC | 0.09% | Add +113.1% | 209,300 | $17.4M |
| Verition Fund Management LLC | 0.10% | Add +648.9% | 208,951 | $17.3M |
| Cibc World Market Inc. | 0.03% | Add +20.6% | 208,036 | $17.3M |
"% of holder's portfolio" is IRM's weight in each manager's 13F, not the share of Iron Mountain Inc. the manager owns.