Iron Mountain Incorporated
US ˙ NYSE ˙ US46284V1017

SecurityIRM / Iron Mountain Incorporated
InstitutionCoston, McIsaac & Partners
Latest Disclosed Ownership192 shares
Latest Disclosed Value $ 19
Coston, McIsaac & Partners reports 0.52% increase in ownership of IRM / Iron Mountain Incorporated

On April 22, 2026 - Coston, McIsaac & Partners filed a 13F-HR form disclosing ownership of 192 shares of Iron Mountain Incorporated (US:IRM) valued at $19,611 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 3, 2026 disclosing 191 shares of Iron Mountain Incorporated. The current value of the position is $23,935 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-04-22 2026-03-31 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 192 1 0.52 0 0.0043
2026-02-03 2025-12-31 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 191 2 1.06 0 0.0035
2025-11-05 2025-09-30 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 189 1 0.53 0 0.0045
2025-08-12 2025-06-30 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 188 2 1.08 0 0.0049
2025-05-13 2025-03-31 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 186 1 0.54 0 0.0047
2025-01-23 2024-12-31 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 185 2 1.09 0 0.0056
2024-10-22 2024-09-30 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 183 1 0.55 0 0.0059
2024-07-31 2024-06-30 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 182 1 0.55 0 0.0050
2024-04-17 2024-03-31 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 181 2 1.12 0 0.0045
2024-01-23 2023-12-31 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 179 2 1.13 0 0.0042
2023-11-14 2023-09-30 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 177 2 1.14 0 0.0038
2023-08-01 2023-06-30 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 175 2 1.16 0 0.0031
2023-04-19 2023-03-31 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 173 2 1.17 0 0.0033
2023-02-09 2022-12-31 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 171 2 1.18 0 -100.00 0.0031
2022-10-31 2022-09-30 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 169 2 1.20 7 -12.50 0.0032
2022-09-21 2022-06-30 13F IRON MTN INC NEW REIT REAL ESTATE INVESTME 46284V101 167 167 8 0.0048
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.