Iron Mountain Inc
IRM- Exchange
- NYSE
- Industry
- Real Estate Investment Trusts
- SEC CIK
- 0001020569
In the last 90 days, Iron Mountain Inc insiders filed 0 open-market purchases and 8 sales; 1,173 institutions reported holding it in 13F filings for Q2 2026, worth $32.4B in total; no superinvestor holds it.
13F holders, Q1 2026
Institutional positions in Iron Mountain Inc as of Mar 31, 2026. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works
- Institutional holders
- 1,090
- +87 vs. Q4 2025
- Shares held
- 253.3M
- +47.9M (+23.4%) vs. Q4 2025
- Total value
- $25.9B
- +$8.81B (+51.7%) vs. Q4 2025
- New holders
- 179
- 401 more added
- Sold out
- 92
- 348 more reduced
8 institutions that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q4 2025: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting IRM on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 1,173 | $32.4B |
| Q1 2026 | 1,090 | $25.9B |
| Q4 2025 | 1,011 | $21.4B |
| Q3 2025 | 1,017 | $25.5B |
| Q2 2025 | 1,045 | $25.5B |
| Q1 2025 | 995 | $21.1B |
| Q4 2024 | 1,067 | $24.9B |
| Q3 2024 | 1,056 | $28.8B |
| Q2 2024 | 967 | $22.2B |
| Q1 2024 | 938 | $19.0B |
| Q4 2023 | 891 | $16.4B |
| Q3 2023 | 831 | $13.7B |
| Q2 2023 | 817 | $12.9B |
| Q1 2023 | 790 | $12.0B |
| Q4 2022 | 782 | $11.4B |
| Q3 2022 | 743 | $10.0B |
| Q2 2022 | 767 | $10.9B |
| Q1 2022 | 777 | $12.4B |
| Q4 2021 | 754 | $12.0B |
| Q3 2021 | 711 | $9.94B |
| Q2 2021 | 687 | $9.70B |
| Q1 2021 | 630 | $8.44B |
Institutions, Q1 2026
Shares, value and share of portfolio for each institution holding Iron Mountain Inc; share changes are against Q4 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| BlackRock, Inc. | 33,021,354 | $3.37B | 0.06% | +101,696+0.3% | Added |
| Vanguard Portfolio Management LLC | 25,015,557 | $2.56B | 0.13% | +25,015,557 | New |
| Vanguard Capital Management LLC | 18,758,889 | $1.92B | 0.05% | +18,758,889 | New |
| State Street Corp | 17,551,633 | $1.81B | 0.06% | +662,835+3.9% | Added |
| Cohen & Steers, Inc. | 16,169,341 | $1.65B | 2.87% | −2,734,375−14.5% | Reduced |
| Geode Capital Management, LLC | 8,486,127 | $863.7M | 0.05% | +193,474+2.3% | Added |
| FMR LLC | 7,484,398 | $764.5M | 0.04% | −499,906−6.3% | Reduced |
| Morgan Stanley | 4,652,247 | $475.2M | 0.03% | +1,053,274+29.3% | Added |
| Principal Financial Group Inc | 4,566,093 | $466.4M | 0.25% | +358,497+8.5% | Added |
| Dimensional Fund Advisors LP | 4,552,286 | $464.9M | 0.10% | +122,927+2.8% | Added |
| Northern Trust Corp | 4,150,486 | $423.9M | 0.06% | −2,083−0.1% | Reduced |
| Charles Schwab Investment Management Inc | 4,013,007 | $409.9M | 0.06% | +132,732+3.4% | Added |
| Invesco Ltd. | 3,921,521 | $400.5M | 0.04% | −495,846−11.2% | Reduced |
| Legal & General Group Plc | 3,135,074 | $320.2M | 0.07% | −221,346−6.6% | Reduced |
| Daiwa Securities Group Inc. | 3,107,440 | $317.4M | 0.92% | −546,646−15.0% | Reduced |
| Deutsche Bank AG | 3,092,084 | $315.8M | 0.10% | +550,092+21.6% | Added |
| Prudential Financial Inc | 2,416,063 | $246.8M | 0.30% | +105,582+4.6% | Added |
| Centersquare Investment Management LLC | 2,310,045 | $235.9M | 2.44% | −321,408−12.2% | Reduced |
| Goldman Sachs Group Inc | 2,216,672 | $226.4M | 0.03% | +691,432+45.3% | Added |
| Vontobel Holding Ltd. | 2,116,877 | $216.2M | 0.74% | +427,631+25.3% | Added |
| Nuveen, LLC | 2,068,408 | $211.3M | 0.06% | −59,523−2.8% | Reduced |
| JPMorgan Chase & Co | 2,123,358 | $207.2M | 0.01% | +195,423+10.1% | Added |
| Capital World Investors | 1,867,169 | $190.7M | 0.03% | −250,000−11.8% | Reduced |
| Ameriprise Financial Inc | 1,851,007 | $189.1M | 0.04% | +106,602+6.1% | Added |
| AQR Capital Management LLC | 1,846,073 | $183.1M | 0.08% | +922,877+100.0% | Added |
| Vanguard Fiduciary Trust Co | 1,652,888 | $168.8M | 0.04% | +1,652,888 | New |
| Bank of New York Mellon Corp | 1,624,836 | $166.0M | 0.03% | −61,142−3.6% | Reduced |
| Duff & Phelps Investment Management Co | 1,575,337 | $160.9M | 1.67% | −5,115−0.3% | Reduced |
| Russell Investments Group, Ltd. | 1,455,113 | $148.4M | 0.16% | +49,353+3.5% | Added |
| Contour Asset Management LLC | 1,444,823 | $147.6M | 4.80% | −1,387,359−49.0% | Reduced |
| Royal Bank of Canada | 1,410,720 | $144.1M | 0.03% | +124,849+9.7% | Added |
| Bank of America Corp | 1,399,375 | $142.9M | 0.01% | −110,970−7.3% | Reduced |
| PGGM Investments | 1,369,998 | $139.9M | 2.45% | −287,161−17.3% | Reduced |
| HSBC Holdings PLC | 1,272,855 | $130.0M | 0.08% | +217,080+20.6% | Added |
| Cbre Clarion Securities LLC | 1,237,915 | $126.4M | 1.87% | −208,682−14.4% | Reduced |
| DekaBank Deutsche Girozentrale | 1,122,500 | $116.6M | 0.19% | 00.0% | Unchanged |
| Amundi | 1,091,574 | $111.5M | 0.03% | −242,119−18.2% | Reduced |
| SEI Investments Co | 974,792 | $99.6M | 0.09% | −49,872−4.9% | Reduced |
| Sumitomo Mitsui Trust Holdings, Inc. | 933,722 | $95.4M | 0.06% | +26,834+3.0% | Added |
| Mitsubishi UFJ Kokusai Asset Management Co., Ltd. | 908,365 | $92.8M | 0.06% | +68,799+8.2% | Added |
| Swiss National Bank | 867,461 | $88.6M | 0.05% | +58,200+7.2% | Added |
| Pictet Asset Management Holding SA | 864,737 | $88.2M | 0.09% | −1,431,228−62.3% | Reduced |
| CIBC Bancorp USA Inc. | 828,793 | $84.6M | 0.11% | +828,793 | New |
| American Century Companies Inc | 815,792 | $83.3M | 0.04% | +419,899+106.1% | Added |
| UBS Group AG | 801,430 | $81.9M | 0.01% | +5,522+0.7% | Added |
| Jane Street Group, LLC | 707,441 | $72.3M | 0.08% | +707,441 | New |
| APG Asset Management US Inc. | 703,912 | $71.1M | 0.55% | +121,738+20.9% | Added |
| Barclays PLC | 673,771 | $68.8M | 0.02% | −55,086−7.6% | Reduced |
| Wells Fargo & Company | 658,454 | $67.3M | 0.01% | +21,182+3.3% | Added |
| Welch & Forbes LLC | 652,068 | $66.6M | 0.86% | −4,296−0.7% | Reduced |
| Vanguard Global Advisers, LLC | 647,775 | $66.2M | 0.04% | +647,775 | New |
| LPL Financial LLC | 621,238 | $63.5M | 0.02% | −13,561−2.1% | Reduced |
| Epoch Investment Partners, Inc. | 616,513 | $63.0M | 0.38% | −13,341−2.1% | Reduced |
| Price T Rowe Associates Inc | 601,581 | $61.4M | 0.01% | −5,278−0.9% | Reduced |
| Universal- Beteiligungs- und Servicegesellschaft mbH | 590,504 | $60.3M | 0.10% | −34,940−5.6% | Reduced |
| Adage Capital Partners GP, L.L.C. | 590,052 | $60.3M | 0.09% | −66,800−10.2% | Reduced |
| Nomura Asset Management International Inc. | 586,881 | $59.9M | 0.10% | +502,658+596.8% | Added |
| Rhumbline Advisers | 578,543 | $59.1M | 0.05% | −11,997−2.0% | Reduced |
| Nomura Asset Management Co Ltd | 563,343 | $57.5M | 0.15% | +18,860+3.5% | Added |
| Worldquant Millennium Advisors LLC | 548,049 | $56.0M | 0.22% | +392,013+251.2% | Added |
| Asset Management One Co.,Ltd. | 547,474 | $55.9M | 0.16% | −8,500−1.5% | Reduced |
| Bamco Inc | 525,270 | $53.7M | 0.16% | +525,270 | New |
| BNP Paribas Arbitrage, SA | 508,511 | $51.9M | 0.03% | −53,742−9.6% | Reduced |
| Vanguard Asset Management, Ltd | 504,995 | $51.6M | 0.04% | +504,995 | New |
| Colony Capital, Inc. | 504,021 | $51.5M | 3.27% | +504,021 | New |
| California Public Employees Retirement System | 502,460 | $51.3M | 0.03% | −11,095−2.2% | Reduced |
| Border to Coast Pensions Partnership Ltd | 470,000 | $48.2M | 0.81% | −30,000−6.0% | Reduced |
| Clark Capital Management Group, Inc. | 468,365 | $47.8M | 0.30% | +468,365 | New |
| Alliancebernstein L.P. | 565,255 | $46.9M | 0.02% | +20,445+3.8% | Added |
| Virginia Retirement Systems Et Al | 440,108 | $45.0M | 0.33% | +315,308+252.7% | Added |
| National Pension Service | 429,392 | $43.9M | 0.03% | −79,628−15.6% | Reduced |
| Public Employees Retirement System of Ohio | 423,714 | $43.3M | 0.14% | +232,207+121.3% | Added |
| California State Teachers Retirement System | 422,871 | $43.2M | 0.05% | −11,234−2.6% | Reduced |
| Bank of Montreal | 406,013 | $41.5M | 0.02% | −30,332−7.0% | Reduced |
| Teacher Retirement System of Texas | 394,701 | $40.3M | 0.17% | +60,730+18.2% | Added |
| Rockefeller Capital Management L.P. | 389,140 | $39.7M | 0.07% | −14,852−3.7% | Reduced |
| Point72 Asset Management, L.P. | 377,618 | $38.6M | 0.07% | −412,886−52.2% | Reduced |
| Citadel Advisors LLC | 374,954 | $38.3M | 0.03% | −744,417−66.5% | Reduced |
| Millennium Management LLC | 374,463 | $38.2M | 0.03% | −114,551−23.4% | Reduced |
| Standard Life Aberdeen plc | 371,208 | $37.9M | 0.06% | +6,319+1.7% | Added |
| Neuberger Berman Group LLC | 360,751 | $36.8M | 0.03% | −70,635−16.4% | Reduced |
| Adelante Capital Management LLC | 356,934 | $36.5M | 2.58% | +17,707+5.2% | Added |
| Wellington Management Group LLP | 347,915 | $35.5M | 0.01% | +243,788+234.1% | Added |
| Vanguard Investments Australia, Ltd. | 343,334 | $35.1M | 0.10% | +343,334 | New |
| Great West Life Assurance Co | 335,860 | $34.4M | 0.06% | −1,075−0.3% | Reduced |
| Quantinno Capital Management LP | 322,017 | $32.9M | 0.05% | +154,910+92.7% | Added |
| Adell Harriman & Carpenter Inc | 315,817 | $32.3M | 1.97% | +1,200+0.4% | Added |
| Citigroup Inc | 315,634 | $32.2M | 0.02% | −2,967−0.9% | Reduced |
| Marble Harbor Investment Counsel, LLC | 300,474 | $30.7M | 3.33% | −13,546−4.3% | Reduced |
| Ensign Peak Advisors, Inc | 297,330 | $30.4M | 0.06% | +222,713+298.5% | Added |
| Raymond James Financial Inc | 295,133 | $30.1M | 0.01% | −71,176−19.4% | Reduced |
| STRS Ohio | 287,817 | $29.4M | 0.12% | −126,311−30.5% | Reduced |
| Macquarie Group Ltd | 270,616 | $27.6M | 0.16% | −22,376−7.6% | Reduced |
| Apollo Management Holdings, L.P. | 265,539 | $27.1M | 0.45% | 00.0% | Unchanged |
| Aviva PLC | 263,200 | $26.9M | 0.05% | +7,075+2.8% | Added |
| State Board of Administration of Florida Retirement System | 262,515 | $26.8M | 0.05% | 00.0% | Unchanged |
| Swedbank AB | 260,330 | $26.6M | 0.03% | −24,528−8.6% | Reduced |
| Cetera Investment Advisers | 260,039 | $26.6M | 0.03% | +11,442+4.6% | Added |
| Heitman Real Estate Securities LLC | 259,594 | $26.5M | 1.91% | −230,954−47.1% | Reduced |
| Stifel Financial Corp | 255,348 | $26.1M | 0.02% | +28,114+12.4% | Added |