IRMIron Mountain

$121.36

Who owns IRM

1,052 institutions reported holding IRM for 2026Q1, together 84% of the company, more than the 979 a quarter earlier.

1,052

Institutions reporting a position · as of 2026Q1 · up from 979 the quarter before

Shares held by institutions
252.3M

Shares held by institutions · 84% of the company · long US equity positions only, as reported on Form 13F

Reported value
$25.7B

Reported value · at 2026-03-31 prices, not today's

Top 5 holders
41%

Top 5 holders · of the whole company, between five filers

Details
Reporting quarter2026-03-31
2026Q1
Quarters on record
52
New positions
165
Positions exited
98
Added to
342
Reduced
321
Top 10 holdersof the company
49%
Institutional ownership by quarter, 2013Q2 to 2026Q1
QuarterFilersSharesReported value
2026Q11,052252.3M$25.7B
2025Q4979257.0M$21.3B
2025Q3992249.5M$25.4B
2025Q21,016248.2M$25.5B
2025Q1971244.2M$21.0B
2024Q41,036236.3M$24.8B
2024Q31,034242.2M$28.7B
2024Q2953247.7M$22.2B
2024Q1918236.9M$19.0B
2023Q4881232.9M$16.3B
2023Q3821229.2M$13.6B
2023Q2803226.5M$12.9B
2023Q1774224.5M$11.9B
2022Q4769228.1M$11.3B
2022Q3734226.1M$9.96B
2022Q2754223.4M$10.9B
Largest reported holders, 2026Q1
HolderShares% of companyValue
VANGUARD GROUP INC47.0M16%$4.80B
BlackRock Inc.33.0M11%$3.37B
STATE STREET CORP17.6M5.9%$1.81B
COHEN & STEERS INC16.2M5.4%$1.65B
GEODE CAPITAL MANAGEMENT LLC8.5M2.8%$864M
FMR LLC7.5M2.5%$764M
MORGAN STANLEY4.7M1.6%$475M
PRINCIPAL FINANCIAL GROUP INC4.6M1.5%$466M
DIMENSIONAL FUND ADVISORS LP4.6M1.5%$465M
NORTHERN TRUST CORP4.2M1.4%$424M

SEC Form 13F data sets (DERA bulk files). 13F is quarterly, filed up to 45 days late, and covers long US equity positions only, no shorts, no derivatives, nothing held below the reporting threshold.

reading the register…