Iron Mountain Incorporated
MX ˙ BMV ˙ US46284V1017
SecurityMX:IRM1 / Iron Mountain Incorporated
InstitutionJanney Montgomery Scott LLC
Latest Disclosed Ownership88,356 shares
Latest Disclosed Value $ 9,025
Janney Montgomery Scott LLC reports 3.35% decrease in ownership of IRM1 / Iron Mountain Incorporated

On April 22, 2026 - Janney Montgomery Scott LLC filed a 13F-HR form disclosing ownership of 88,356 shares of Iron Mountain Incorporated (MX:IRM1) valued at $9,025 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 91,418 shares of Iron Mountain Incorporated. This represents a change in shares of -3.35% 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)
2026-04-22 2026-03-31 13F IRON MOUNTAIN REIT 46284V101 88,356 -3,062 -3.35 9 28.57 0.0223
2026-02-11 2025-12-31 13F IRON MOUNTAIN REIT 46284V101 91,418 -131 -0.14 8 -22.22 0.0174
2025-10-27 2025-09-30 13F IRON MOUNTAIN REIT 46284V101 91,549 841 0.93 9 0.00 0.0221
2025-07-17 2025-06-30 13F IRON MOUNTAIN REIT 46284V101 90,708 -222 -0.24 9 28.57 0.0243
2025-04-17 2025-03-31 13F IRON MOUNTAIN REIT 46284V101 90,930 -1,433 -1.55 8 -22.22 0.0222
2025-01-17 2024-12-31 13F IRON MOUNTAIN REIT 46284V101 92,363 4,350 4.94 10 -10.00 0.0269
2024-10-29 2024-09-30 13F IRON MOUNTAIN REIT 46284V101 88,013 -21,297 -19.48 10 11.11 0.0292
2024-07-25 2024-06-30 13F IRON MOUNTAIN REIT 46284V101 109,310 316 0.29 10 12.50 0.0299
2024-05-01 2024-03-31 13F IRON MOUNTAIN REIT 46284V101 108,994 -51,552 -32.11 9 -27.27 0.0260
2024-02-08 2023-12-31 13F IRON MOUNTAIN REIT 46284V101 160,546 -5,465 -3.29 11 22.22 0.0365
2023-11-08 2023-09-30 13F IRON MOUNTAIN REIT 46284V101 166,011 -2,116 -1.26 10 0.00 0.0368
2023-07-26 2023-06-30 13F IRON MOUNTAIN REIT 46284V101 168,127 -2,500 -1.47 10 0.00 0.0333
2023-04-28 2023-03-31 13F IRON MOUNTAIN REIT 46284V101 170,627 10,512 6.57 9 28.57 0.0369
2023-02-01 2022-12-31 13F IRON MOUNTAIN REIT 46284V101 160,115 13,383 9.12 8 -99.89 0.0311
2022-10-25 2022-09-30 13F IRON MOUNTAIN REIT 46284V101 146,732 -15,087 -9.32 6,452 -18.68 0.0276
2022-08-03 2022-06-30 13F IRON MOUNTAIN REIT 46284V101 161,819 6,270 4.03 7,934 -7.95 0.0358
2022-05-04 2022-03-31 13F INV DWA HLTHCARE ETF REIT 46284V101 155,549 5,965 3.99 8,619 10.10 0.0369
2022-01-27 2021-12-31 13F IRON MOUNTAIN REIT 46284V101 149,584 5,963 4.15 7,828 25.43 0.0304
2021-10-29 2021-09-30 13F IRON MOUNTAIN REIT 46284V101 143,621 27,433 23.61 6,241 26.93 0.0267
2021-07-26 2021-06-30 13F IRON MOUNTAIN REIT 46284V101 116,188 -8,164 -6.57 4,917 6.84 0.0217
2021-04-27 2021-03-31 13F IRON MOUNTAIN REIT 46284V101 124,352 31,482 33.90 4,602 68.08 0.0224
2021-01-25 2020-12-31 13F IRON MOUNTAIN INC REIT 46284V101 92,870 15,242 19.63 2,738 31.63 0.0132
2020-11-06 2020-09-30 13F IRON MOUNTAIN INC REIT 46284V101 77,628 2,249 2.98 2,080 5.74 0.0119
2020-07-23 2020-06-30 13F IRON MOUNTAIN INC REIT 46284V101 75,379 -42,265 -35.93 1,967 -29.75 0.0124
2020-04-30 2020-03-31 13F IRON MOUNTAIN INC REIT 46284V101 117,644 14,198 13.73 2,800 -15.07 0.0222
2020-01-21 2019-12-31 13F IRON MOUNTAIN INC REIT 46284V101 103,446 11,180 12.12 3,297 10.30 0.0216
2019-10-29 2019-09-30 13F IRON MOUNTAIN INC REIT 46284V101 92,266 -18,122 -16.42 2,989 -13.49 0.0218
2019-07-29 2019-06-30 13F IRON MOUNTAIN INC REIT 46284V101 110,388 12,939 13.28 3,455 -0.03 0.0265
2019-04-30 2019-03-31 13F/A-1 IRON MOUNTAIN INC REIT 46284V101 97,449 14,211 17.07 3,456 28.09 0.0284
2019-04-30 2019-03-31 13F IRON MOUNTAIN INC REIT 46284V101 83,238 0 2,698
2019-02-01 2018-12-31 13F IRON MOUNTAIN INC REIT 46284V101 83,238 5,969 7.72 2,698 1.16 0.0260
2018-11-05 2018-09-30 13F IRON MOUNTAIN INC REIT 46284V101 77,269 8,749 12.77 2,667 11.17 0.0230
2018-07-24 2018-06-30 13F IRON MOUNTAIN INC REIT 46284V101 68,520 17,911 35.39 2,399 44.26 0.0231
2018-04-19 2018-03-31 13F IRON MOUNTAIN INC REIT 46284V101 50,609 3,418 7.24 1,663 -6.63 0.0167
2018-02-14 2017-12-31 13F IRON MOUNTAIN INC REIT 46284V101 47,191 3,208 7.29 1,781 4.09 0.0185
2017-11-15 2017-09-30 13F IRON MOUNTAIN INC REIT 46284V101 43,983 2,152 5.14 1,711 19.07 0.0195
2017-07-27 2017-06-30 13F IRON MOUNTAIN INC REIT 46284V101 41,831 -11,606 -21.72 1,437 -24.61 0.0179
2017-04-26 2017-03-31 13F IRON MOUNTAIN INC REIT 46284V101 53,437 -7,915 -12.90 1,906 -4.37 0.0254
2017-02-13 2016-12-31 13F IRON MOUNTAIN INC REIT 46284V101 61,352 22,529 58.03 1,993 36.79 0.0301
2016-11-14 2016-09-30 13F IRON MOUNTAIN INC REIT 46284V101 38,823 16,458 73.59 1,457 141.23 0.0257
2016-08-05 2016-06-30 13F IRON MOUNTAIN INC REIT 46284V101 22,365 153 0.69 604 -19.79 0.0095
2016-05-10 2016-03-31 13F IRON MOUNTAIN INC REIT 46284V101 22,212 -153 -0.68 753 24.67 0.0197
2016-02-19 2015-12-31 13F IRON MOUNTAIN INC REIT 46284V101 22,365 1,597 7.69 604 -6.21 0.0156
2015-11-16 2015-09-30 13F IRON MOUNTAIN INC REIT 46284V101 20,768 -135 -0.65 644 -0.46 0.0182
2015-08-04 2015-06-30 13F IRON MOUNTAIN INC REIT 46284V101 20,903 -2,532 -10.80 648 -24.33 0.0136
2015-05-12 2015-03-31 13F/A-1 IRON MOUNTAIN INC REIT 46284V101 23,435 14,738 169.46 855 154.46 0.0159
2015-04-30 2015-03-31 13F IRON MOUNTAIN INC REIT 46284V101 23,435 855
2015-02-10 2014-12-31 13F IRON MOUNTAIN INC PA Common Stock 462846106 8,697 1,172 15.57 336 37.14 0.0067
2014-11-14 2014-09-30 13F IRON MOUNTAIN INC DE Common Stock 462846106 7,525 7,525 246 0.0051
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.