Iron Mountain Incorporated
MX ˙ BMV ˙ US46284V1017
SecurityMX:IRM1 / Iron Mountain Incorporated
InstitutionUnited Bank
Latest Disclosed Ownership141,636 shares
Latest Disclosed Value $ 14,466,695
United Bank reports 4.95% decrease in ownership of IRM1 / Iron Mountain Incorporated

On May 11, 2026 - United Bank filed a 13F-HR form disclosing ownership of 141,636 shares of Iron Mountain Incorporated (MX:IRM1) valued at $14,466,695 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 149,014 shares of Iron Mountain Incorporated. This represents a change in shares of -4.95% during the quarter.

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)
2026-05-11 2026-03-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 141,636 -7,378 -4.95 14,467 17.04 1.8528
2026-02-13 2025-12-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 149,014 -18,506 -11.05 12,361 -27.62 1.6327
2025-11-07 2025-09-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 167,520 -13,489 -7.45 17,077 -8.03 2.0353
2025-07-18 2025-06-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 181,009 -7,166 -3.81 18,566 14.68 2.2226
2025-05-14 2025-03-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 188,175 -25,913 -12.10 16,191 -28.05 2.0597
2025-05-14 2024-12-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 214,088 -4,375 -2.00 22,503 -13.32 2.6823
2024-11-15 2024-09-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 218,463 -2,357 -1.07 25,960 31.18 3.0211
2024-08-14 2024-06-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 220,820 -25,669 -10.41 19,790 0.10 2.4557
2024-05-13 2024-03-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 246,489 -41,480 -14.40 19,771 -1.90 2.3598
2024-02-07 2023-12-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 287,969 -7,293 -2.47 20,152 14.81 2.5298
2023-11-08 2023-09-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 295,262 -5,745 -1.91 17,553 2.63 2.3059
2023-08-03 2023-06-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 301,007 -16,995 -5.34 17,103 1.65 2.1027
2023-05-01 2023-03-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 318,002 -17,570 -5.24 16,825 0.58 2.1497
2023-02-14 2022-12-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 335,572 7,823 2.39 16,728 16.08 2.3445
2022-11-14 2022-09-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 327,749 173 0.05 14,411 -9.65 2.2184
2022-08-12 2022-06-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 327,576 -22,253 -6.36 15,951 -17.71 2.3917
2022-05-16 2022-03-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 349,829 -24,244 -6.48 19,384 -0.97 2.5495
2022-02-11 2021-12-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 374,073 -7,391 -1.94 19,574 18.09 2.4053
2021-10-21 2021-09-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 381,464 -10,236 -2.61 16,575 -0.01 2.2194
2021-08-16 2021-06-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 391,700 -4,452 -1.12 16,577 13.06 2.2289
2021-04-23 2021-03-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 396,152 -8,023 -1.99 14,662 23.05 2.0137
2021-02-18 2020-12-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 404,175 20,099 5.23 11,915 15.80 1.7820
2020-12-11 2020-09-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 384,076 3,363 0.88 10,289 3.54 1.7963
2020-09-18 2020-06-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 380,713 38,565 11.27 9,937 22.03 1.8007
2020-05-14 2020-03-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 342,148 9,615 2.89 8,143 -23.16 1.7672
2020-02-14 2019-12-31 13F IRON MOUNTAIN COMMON STOCK 46284V101 332,533 3,395 1.03 10,598 -0.58 1.8360
2019-11-13 2019-09-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 329,138 -11,678 -3.43 10,660 -0.07 1.9487
2019-08-15 2019-06-30 13F IRON MOUNTAIN COMMON STOCK 46284V101 340,816 340,816 10,667 1.7827
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.