Iron Mountain Incorporated
US ˙ NYSE ˙ US46284V1017

SecurityIRM / Iron Mountain Incorporated
InstitutionPrivate Advisor Group, LLC
Latest Disclosed Ownership85,309 shares
Latest Disclosed Value $ 8,713,530
Private Advisor Group, LLC reports 1.16% decrease in ownership of IRM / Iron Mountain Incorporated

On April 24, 2026 - Private Advisor Group, LLC filed a 13F-HR form disclosing ownership of 85,309 shares of Iron Mountain Incorporated (US:IRM) valued at $8,713,461 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 86,310 shares of Iron Mountain Incorporated. This represents a change in shares of -1.16% during the quarter. The current value of the position is $10,915,287 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)
2026-04-24 2026-03-31 13F IRON MTN INC DEL COM 46284V101 85,309 -1,001 -1.16 8,714 21.71 0.0387
2026-02-17 2025-12-31 13F IRON MTN INC DEL COM 46284V101 86,310 -7,746 -8.24 7,159 -25.33 0.0322
2025-11-13 2025-09-30 13F IRON MTN INC DEL COM 46284V101 94,056 -4,994 -5.04 9,588 -5.62 0.0472
2025-08-11 2025-06-30 13F IRON MTN INC DEL COM 46284V101 99,050 -312 -0.31 10,160 18.83 0.0547
2025-05-05 2025-03-31 13F IRON MTN INC DEL COM 46284V101 99,362 4,282 4.50 8,549 -14.45 0.0517
2025-02-03 2024-12-31 13F IRON MTN INC DEL COM 46284V101 95,080 2,012 2.16 9,994 -9.64 0.0563
2024-10-22 2024-09-30 13F IRON MTN INC DEL COM 46284V101 93,068 -917 -0.98 11,059 31.31 0.0687
2024-08-05 2024-06-30 13F IRON MTN INC DEL COM 46284V101 93,985 8,877 10.43 8,423 23.38 0.0565
2024-04-30 2024-03-31 13F IRON MTN INC DEL COM 46284V101 85,108 1,778 2.13 6,827 17.06 0.0491
2024-02-06 2023-12-31 13F IRON MTN INC DEL COM 46284V101 83,330 -1,429 -1.69 5,831 15.74 0.0453
2023-11-03 2023-09-30 13F IRON MTN INC DEL COM 46284V101 84,759 1,581 1.90 5,039 5.68 0.0450
2023-08-10 2023-06-30 13F IRON MTN INC DEL COM 46284V101 83,178 -1,690 -1.99 4,767 6.17 0.0414
2023-05-10 2023-03-31 13F IRON MTN INC DEL COM 46284V101 84,868 -1,893 -2.18 4,490 979.33 0.0429
2023-01-18 2022-12-31 13F IRON MTN INC DEL COM 46284V101 86,761 11,457 15.21 417 -87.44 0.0210
2022-10-14 2022-09-30 13F IRON MTN INC DEL COM 46284V101 75,304 -27,028 -26.41 3,311 -33.55 0.0381
2022-07-13 2022-06-30 13F IRON MTN INC COM 46284V101 102,332 -1,540 -1.48 4,983 -13.43 0.0444
2022-05-12 2022-03-31 13F/A-1 IRON MTN INC COM 46284V101 103,872 13,261 14.64 5,756 21.38 0.0441
2022-05-10 2022-03-31 13F IRON MTN INC COM 46284V101 90,611 0 4,742 0.0356
2022-02-10 2021-12-31 13F IRON MTN INC COM 46284V101 90,611 -6,187 -6.39 4,742 12.74 0.0356
2021-10-14 2021-09-30 13F IRON MTN INC COM 46284V101 96,798 21,489 28.53 4,206 31.97 0.0267
2021-08-12 2021-06-30 13F IRON MTN INC COM 46284V101 75,309 1,173 1.58 3,187 16.14 0.0278
2021-04-22 2021-03-31 13F IRON MTN INC COM 46284V101 74,136 5,434 7.91 2,744 35.51 0.0262
2021-04-01 2020-12-31 13F IRON MTN INC COM 46284V101 68,702 -1,809 -2.57 2,025 7.20 0.0211
2020-11-02 2020-09-30 13F IRON MTN INC COM 46284V101 70,511 7,112 11.22 1,889 14.14 0.0246
2020-08-17 2020-06-30 13F IRON MTN INC COM 46284V101 63,399 7,511 13.44 1,655 24.44 0.0230
2020-05-12 2020-03-31 13F IRON MTN INC COM 46284V101 55,888 12,943 30.14 1,330 -2.85 0.0244
2020-02-10 2019-12-31 13F IRON MTN INC COM 46284V101 42,945 1,106 2.64 1,369 0.51 0.0213
2019-11-13 2019-09-30 13F IRON MTN INC COM 46284V101 41,839 15,962 61.68 1,362 68.15 0.0212
2019-08-14 2019-06-30 13F IRON MTN INC COM 46284V101 25,877 5,159 24.90 810 10.20 0.0146
2019-05-13 2019-03-31 13F IRON MTN INC COM 46284V101 20,718 7,008 51.12 735 65.54 0.0145
2019-02-08 2018-12-31 13F IRON MTN INC COM 46284V101 13,710 -8,321 -37.77 444 -41.66 0.0107
2018-11-01 2018-09-30 13F IRON MTN INC COM 46284V101 22,031 12,232 124.83 761 121.87 0.0156
2018-08-09 2018-06-30 13F IRON MTN INC COM 46284V101 9,799 -742 -7.04 343 -0.87 0.0056
2018-05-09 2018-03-31 13F IRON MTN INC COM 46284V101 10,541 4,688 80.10 346 59.45 0.0135
2018-02-07 2017-12-31 13F IRON MTN INC COM 46284V101 5,853 -7,091 -54.78 217 -56.25 0.0092
2017-11-13 2017-09-30 13F IRON MTN INC COM 46284V101 12,944 5,015 63.25 496 87.17 0.0123
2017-08-10 2017-06-30 13F IRON MTN INC COM 46284V101 7,929 -2,443 -23.55 265 -27.40 0.0072
2017-05-10 2017-03-31 13F IRON MTN INC COM 46284V101 10,372 10,372 365 0.0102
2015-08-13 2015-06-30 13F IRON MTN INC COM 46284V101 0 -9,591 -100.00 0 -100.00
2015-05-13 2015-03-31 13F IRON MTN INC COM 46284V101 9,591 58 0.61 350 -5.15 0.0202
2015-02-17 2014-12-31 13F IRON MTN COM 462846106 9,533 -772 -7.49 369 9.82 0.0238
2014-11-12 2014-09-30 13F IRON MTN COM 462846106 10,305 10,305 336 0.0232
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.