Skip to main content

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, Q3 2025

Institutional positions in Iron Mountain Inc as of Sep 30, 2025. 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
1,017
−13 vs. Q2 2025
Shares held
250.3M
+5.90M (+2.4%) vs. Q2 2025
Total value
$25.5B
+$450.7M (+1.8%) vs. Q2 2025
New holders
75
370 more added
Sold out
88
390 more reduced

15 institutions that held it in Q2 2025 haven't filed for Q3 2025 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.

Compare with Q2 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.

Institutional holdersQ3 2025: 1,017 institutions
Q1 2021: 630 institutionsQ2 2021: 687 institutionsQ3 2021: 711 institutionsQ4 2021: 754 institutionsQ1 2022: 777 institutionsQ2 2022: 767 institutionsQ3 2022: 743 institutionsQ4 2022: 782 institutionsQ1 2023: 790 institutionsQ2 2023: 817 institutionsQ3 2023: 831 institutionsQ4 2023: 891 institutionsQ1 2024: 938 institutionsQ2 2024: 967 institutionsQ3 2024: 1,056 institutionsQ4 2024: 1,067 institutionsQ1 2025: 995 institutionsQ2 2025: 1,045 institutionsQ3 2025: 1,017 institutionsQ4 2025: 1,011 institutionsQ1 2026: 1,090 institutionsQ2 2026: 1,173 institutions
Value heldQ3 2025: $25.5B
Q1 2021: $8.44BQ2 2021: $9.70BQ3 2021: $9.94BQ4 2021: $12.0BQ1 2022: $12.4BQ2 2022: $10.9BQ3 2022: $10.0BQ4 2022: $11.4BQ1 2023: $12.0BQ2 2023: $12.9BQ3 2023: $13.7BQ4 2023: $16.4BQ1 2024: $19.0BQ2 2024: $22.2BQ3 2024: $28.8BQ4 2024: $24.9BQ1 2025: $21.1BQ2 2025: $25.5BQ3 2025: $25.5BQ4 2025: $21.4BQ1 2026: $25.9BQ2 2026: $32.4B
Institutions holding IRM and their total value by quarter
QuarterHoldersValue
Q2 20261,173$32.4B
Q1 20261,090$25.9B
Q4 20251,011$21.4B
Q3 20251,017$25.5B
Q2 20251,045$25.5B
Q1 2025995$21.1B
Q4 20241,067$24.9B
Q3 20241,056$28.8B
Q2 2024967$22.2B
Q1 2024938$19.0B
Q4 2023891$16.4B
Q3 2023831$13.7B
Q2 2023817$12.9B
Q1 2023790$12.0B
Q4 2022782$11.4B
Q3 2022743$10.0B
Q2 2022767$10.9B
Q1 2022777$12.4B
Q4 2021754$12.0B
Q3 2021711$9.94B
Q2 2021687$9.70B
Q1 2021630$8.44B

Institutions, Q3 2025

Shares, value and share of portfolio for each institution holding Iron Mountain Inc; share changes are against Q2 2025.

Institutions holding IRM in Q3 2025
InstitutionSharesValue% of portfolioChange in sharesAction
Vanguard Group Inc47,253,100$4.82B0.07%+188,213+0.4%Added
BlackRock, Inc.31,709,064$3.23B0.06%+430,437+1.4%Added
State Street Corp17,131,787$1.76B0.06%+322,144+1.9%Added
Cohen & Steers, Inc.15,748,682$1.61B2.90%+1,980,051+14.4%Added
Geode Capital Management, LLC8,190,580$831.7M0.05%+103,862+1.3%Added
FMR LLC7,858,092$801.1M0.04%+1,160,673+17.3%Added
Invesco Ltd.5,066,516$516.5M0.08%+776,933+18.1%Added
Dimensional Fund Advisors LP4,348,039$443.2M0.10%+55,273+1.3%Added
Northern Trust Corp4,031,566$411.0M0.05%−36,242−0.9%Reduced
Charles Schwab Investment Management Inc3,674,245$374.6M0.06%+48,437+1.3%Added
Morgan Stanley3,611,399$368.1M0.02%+104,916+3.0%Added
Legal & General Group Plc3,215,455$327.8M0.07%−67,821−2.1%Reduced
Contour Asset Management LLC3,165,830$322.7M8.09%+830,482+35.6%Added
UBS Asset Management Americas Inc3,161,589$322.3M0.07%+2,708,560+597.9%Added
Daiwa Securities Group Inc.3,151,088$321.2M1.08%+196,161+6.6%Added
Deutsche Bank AG2,890,451$294.7M0.10%−539,030−15.7%Reduced
Principal Financial Group Inc2,527,158$257.6M0.13%−57,698−2.2%Reduced
Centersquare Investment Management LLC2,514,464$256.3M2.58%+483,548+23.8%Added
Pictet Asset Management Holding SA2,464,168$251.1M0.24%−11,503−0.5%Reduced
Royal Bank of Canada2,298,983$234.4M0.04%+256,188+12.5%Added
Nuveen, LLC2,142,505$218.4M0.06%+87,716+4.3%Added
Capital World Investors2,117,169$215.8M0.03%00.0%Unchanged
Prudential Financial Inc2,113,617$215.5M0.26%+167,848+8.6%Added
JPMorgan Chase & Co2,056,448$209.6M0.01%+83,450+4.2%Added
Russell Investments Group, Ltd.1,706,435$173.9M0.20%−117,229−6.4%Reduced
Ameriprise Financial Inc1,706,032$173.8M0.04%+2080.0%Added
PGGM Investments1,684,781$171.7M2.78%+118,989+7.6%Added
Bank of New York Mellon Corp1,666,560$169.9M0.03%−80,916−4.6%Reduced
Duff & Phelps Investment Management Co1,642,074$167.4M1.90%+169,495+11.5%Added
UBS Group AG1,436,301$146.4M0.03%−363,926−20.2%Reduced
Goldman Sachs Group Inc1,354,097$138.0M0.02%−525,874−28.0%Reduced
Point72 Asset Management, L.P.1,296,531$132.2M0.29%+282,152+27.8%Added
Cbre Clarion Securities LLC1,269,467$129.4M1.85%+196,369+18.3%Added
Bank of America Corp1,227,950$125.2M0.01%−21,492−1.7%Reduced
Amundi1,085,307$115.4M0.04%−515,511−32.2%Reduced
DekaBank Deutsche Girozentrale1,122,500$112.3M0.19%00.0%Unchanged
Vontobel Holding Ltd.1,078,487$109.9M0.35%+1,078,487New
HSBC Holdings PLC951,576$96.9M0.06%+167,280+21.3%Added
Sumitomo Mitsui Trust Holdings, Inc.934,752$95.3M0.05%+10,338+1.1%Added
SEI Investments Co872,870$89.0M0.10%−12,210−1.4%Reduced
Swiss National Bank850,561$86.7M0.05%−38,700−4.4%Reduced
Mitsubishi UFJ Kokusai Asset Management Co., Ltd.802,312$81.8M0.06%+35,724+4.7%Added
Captrust Financial Advisors768,266$78.3M0.16%−915−0.1%Reduced
Barclays PLC739,890$75.4M0.03%+196,194+36.1%Added
CIBC Private Wealth Group, LLC721,087$73.5M0.13%−12,162−1.7%Reduced
LPL Financial LLC709,400$72.3M0.02%+35,804+5.3%Added
Welch & Forbes LLC658,992$67.2M0.81%−9,946−1.5%Reduced
Epoch Investment Partners, Inc.650,757$66.3M0.36%−32,855−4.8%Reduced
Wells Fargo & Company637,840$65.0M0.01%+12,363+2.0%Added
Rhumbline Advisers596,637$60.8M0.05%−23,257−3.8%Reduced
Price T Rowe Associates Inc595,595$60.7M0.01%−31,445−5.0%Reduced
APG Asset Management US Inc.582,174$59.5M0.44%00.0%Unchanged
Alliancebernstein L.P.555,994$56.7M0.02%−5,292−0.9%Reduced
Adage Capital Partners GP, L.L.C.553,420$56.4M0.09%−6,832−1.2%Reduced
American Century Companies Inc552,049$56.3M0.03%−193,217−25.9%Reduced
Asset Management One Co.,Ltd.551,714$56.2M0.16%−4,236−0.8%Reduced
Nomura Asset Management Co Ltd529,048$53.9M0.14%+11,330+2.2%Added
BNP Paribas Arbitrage, SA526,270$53.6M0.04%+99,645+23.4%Added
DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main515,006$52.5M0.05%+137,199+36.3%Added
California Public Employees Retirement System513,415$52.3M0.03%+19,530+4.0%Added
Universal- Beteiligungs- und Servicegesellschaft mbH497,720$50.7M0.08%+19,540+4.1%Added
National Pension Service495,480$50.5M0.04%+19,319+4.1%Added
Millennium Management LLC485,417$49.5M0.04%−90,552−15.7%Reduced
Border to Coast Pensions Partnership Ltd480,000$48.9M0.85%00.0%Unchanged
Heitman Real Estate Securities LLC474,368$48.4M3.30%+10,850+2.3%Added
AQR Capital Management LLC457,472$46.4M0.03%+351,463+331.5%Added
California State Teachers Retirement System440,557$44.9M0.05%−11,644−2.6%Reduced
Great West Life Assurance Co445,064$44.7M0.06%+7,410+1.7%Added
Bamco Inc436,831$44.5M0.12%+329,307+306.3%Added
Citigroup Inc419,723$42.8M0.03%+215,308+105.3%Added
Neuberger Berman Group LLC416,248$42.4M0.03%+51,622+14.2%Added
Rockefeller Capital Management L.P.407,455$41.6M0.08%+28,566+7.5%Added
Bank of Montreal398,180$40.6M0.02%+31,746+8.7%Added
Adelante Capital Management LLC386,285$39.4M2.72%−16,920−4.2%Reduced
Raymond James Financial Inc380,348$38.8M0.01%−12,594−3.2%Reduced
Standard Life Aberdeen plc382,634$38.4M0.06%+42,971+12.7%Added
Adell Harriman & Carpenter Inc326,315$33.3M2.02%+2,015+0.6%Added
Marble Harbor Investment Counsel, LLC325,260$33.2M3.47%−3,513−1.1%Reduced
Blair William & Co318,410$32.5M0.09%+4,280+1.4%Added
Aew Capital Management L P315,257$32.1M1.79%−304,420−49.1%Reduced
KBC Group NV292,478$29.8M0.07%+226,790+345.3%Added
Gillson Capital LP286,900$29.2M2.54%−82,237−22.3%Reduced
Macquarie Group Ltd286,584$29.2M0.03%−2,400−0.8%Reduced
Swedbank AB284,858$29.0M0.03%−30,202−9.6%Reduced
State Board of Administration of Florida Retirement System270,757$27.6M0.05%−25,229−8.5%Reduced
STRS Ohio257,515$26.3M0.10%+32,903+14.6%Added
Cetera Investment Advisers254,352$25.9M0.03%+84,900+50.1%Added
Regions Financial Corp251,781$25.7M0.17%+3,495+1.4%Added
Wellington Management Group LLP248,892$25.4M0.00%−1,245,031−83.3%Reduced
Aviva PLC242,449$24.7M0.04%+14,210+6.2%Added
Pacer Advisors, Inc.231,235$23.6M0.06%+10,952+5.0%Added
Retirement Systems of Alabama230,939$23.5M0.08%−306−0.1%Reduced
Worldquant Millennium Advisors LLC230,912$23.5M0.10%−37,245−13.9%Reduced
New York State Teachers Retirement System227,870$23.2M0.05%−550.0%Reduced
Victory Capital Management Inc222,934$22.7M0.01%−9,020−3.9%Reduced
Stifel Financial Corp218,137$22.2M0.02%+2,901+1.3%Added
Andra AP-fonden215,700$22.0M0.28%−30,200−12.3%Reduced
Canada Pension Plan Investment Board210,283$21.4M0.02%+102,327+94.8%Added
Brookstone Capital Management207,443$21.1M0.25%+59,383+40.1%Added
National Bank of Canada203,663$20.8M0.02%−23,726−10.4%Reduced