Iron Mountain Incorporated
MX ˙ BMV ˙ US46284V1017
SecurityMX:IRM1 / Iron Mountain Incorporated
InstitutionSignaturefd, Llc
Latest Disclosed Ownership6,120 shares
Latest Disclosed Value $ 625,102
Signaturefd, Llc reports 9.19% increase in ownership of IRM1 / Iron Mountain Incorporated

On April 7, 2026 - Signaturefd, Llc filed a 13F-HR form disclosing ownership of 6,120 shares of Iron Mountain Incorporated (MX:IRM1) valued at $625,102 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 20, 2026 disclosing 5,605 shares of Iron Mountain Incorporated. This represents a change in shares of 9.19% 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)
2026-04-07 2026-03-31 13F IRON MTN INC DEL COM 46284V101 6,120 515 9.19 625 34.70 0.0096
2026-01-20 2025-12-31 13F IRON MTN INC DEL COM 46284V101 5,605 -110 -1.92 465 -20.27 0.0071
2025-10-21 2025-09-30 13F IRON MTN INC DEL COM 46284V101 5,715 -1,330 -18.88 583 -19.39 0.0092
2025-07-16 2025-06-30 13F IRON MTN INC DEL COM 46284V101 7,045 822 13.21 723 34.95 0.0123
2025-05-02 2025-03-31 13F IRON MTN INC DEL COM 46284V101 6,223 -18 -0.29 535 -18.32 0.0101
2025-02-10 2024-12-31 13F IRON MTN INC DEL COM 46284V101 6,241 215 3.57 656 -8.52 0.0124
2024-10-21 2024-09-30 13F IRON MTN INC DEL COM 46284V101 6,026 677 12.66 716 49.48 0.0136
2024-07-29 2024-06-30 13F IRON MTN INC DEL COM 46284V101 5,349 97 1.85 479 13.78 0.0097
2024-05-03 2024-03-31 13F IRON MTN INC DEL COM 46284V101 5,252 345 7.03 421 22.74 0.0089
2024-02-01 2023-12-31 13F IRON MTN INC DEL COM 46284V101 4,907 1,316 36.65 343 61.03 0.0079
2023-11-03 2023-09-30 13F IRON MTN INC DEL COM 46284V101 3,591 -535 -12.97 213 -8.97 0.0056
2023-08-01 2023-06-30 13F IRON MTN INC DEL COM 46284V101 4,126 704 20.57 234 29.28 0.0060
2023-04-28 2023-03-31 13F IRON MTN INC DEL COM 46284V101 3,422 112 3.38 181 9.70 0.0049
2023-01-30 2022-12-31 13F IRON MTN INC DEL COM 46284V101 3,310 -101 -2.96 165 10.00 0.0048
2022-11-08 2022-09-30 13F IRON MTN INC DEL COM 46284V101 3,411 -589 -14.72 150 -23.08 0.0051
2022-08-10 2022-06-30 13F IRON MTN INC COM 46284V101 4,000 -2 -0.05 195 -12.16 0.0066
2022-05-02 2022-03-31 13F IRON MTN INC COM 46284V101 4,002 -99 -2.41 222 3.26 0.0067
2022-01-25 2021-12-31 13F IRON MTN INC COM 46284V101 4,101 291 7.64 215 29.52 0.0066
2021-10-28 2021-09-30 13F IRON MTN INC COM 46284V101 3,810 361 10.47 166 13.70 0.0057
2021-07-26 2021-06-30 13F IRON MTN INC COM 46284V101 3,449 8 0.23 146 14.96 0.0058
2021-04-30 2021-03-31 13F IRON MTN INC COM 46284V101 3,441 -196 -5.39 127 18.69 0.0056
2021-02-11 2020-12-31 13F IRON MTN INC COM 46284V101 3,637 1,036 39.83 107 52.86 0.0050
2020-11-03 2020-09-30 13F IRON MTN INC COM 46284V101 2,601 -436 -14.36 70 -11.39 0.0037
2020-07-30 2020-06-30 13F IRON MTN INC COM 46284V101 3,037 415 15.83 79 27.42 0.0048
2020-04-23 2020-03-31 13F IRON MTN INC COM 46284V101 2,622 1,227 87.96 62 40.91 0.0054
2020-02-05 2019-12-31 13F IRON MTN INC COM 46284V101 1,395 9 0.65 44 -2.22 0.0032
2019-10-16 2019-09-30 13F IRON MTN INC COM 46284V101 1,386 1,156 502.61 45 542.86 0.0037
2019-07-31 2019-06-30 13F IRON MTN INC COM 46284V101 230 24 11.65 7 0.00 0.0006
2019-05-09 2019-03-31 13F IRON MTN INC COM 46284V101 206 0 0.00 7 0.00 0.0006
2019-02-13 2018-12-31 13F IRON MTN INC COM 46284V101 206 -211 -50.60 7 -50.00 0.0007
2018-11-14 2018-09-30 13F IRON MTN INC COM 46284V101 417 -130 -23.77 14 -26.32 0.0014
2018-08-14 2018-06-30 13F IRON MTN INC COM 46284V101 547 449 458.16 19 533.33 0.0021
2018-05-08 2018-03-31 13F IRON MTN INC COM 46284V101 98 98 3 0.0004
2017-02-14 2016-12-31 13F IRON MTN INC COM 46284V101 0 -2,105 -100.00 0 -100.00
2016-11-14 2016-09-30 13F IRON MTN INC COM 46284V101 2,105 2,105 79 0.0115
2014-08-14 2014-06-30 13F IRON MTN COM 462846106 0 -190 -100.00 0 -100.00
2014-05-16 2014-03-31 13F IRON MTN COM 462846106 190 190 5 0.0020
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.