Iron Mountain Incorporated
US ˙ NYSE ˙ US46284V1017

SecurityIRM / Iron Mountain Incorporated
InstitutionCandriam Luxembourg S.C.A.
Latest Disclosed Ownership53,827 shares
Latest Disclosed Value $ 5,497,890
Candriam Luxembourg S.C.A. reports 11.97% decrease in ownership of IRM / Iron Mountain Incorporated

On April 30, 2026 - Candriam Luxembourg S.C.A. filed a 13F-HR form disclosing ownership of 53,827 shares of Iron Mountain Incorporated (US:IRM) valued at $5,497,890 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on April 30, 2026 disclosing 61,143 shares of Iron Mountain Incorporated. This represents a change in shares of -11.97% during the quarter. The current value of the position is $6,710,074 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)
2026-04-30 2026-03-31 13F IRON MTN INC DEL COM 46284V101 53,827 -7,316 -11.97 5,498 8.38 0.0286
2026-04-30 2025-12-31 13F/A-1 IRON MTN INC DEL COM 46284V101 61,143 2,037 3.45 5,072 -15.82 0.0253
2026-02-13 2025-12-31 13F IRON MTN INC DEL COM 46284V101 61,143 2,037 5,072 0.0253
2025-11-06 2025-09-30 13F IRON MTN INC DEL COM 46284V101 59,106 -12,617 -17.59 6,025 -18.09 0.0315
2025-08-08 2025-06-30 13F IRON MTN INC DEL COM 46284V101 71,723 1,706 2.44 7,357 22.11 0.0424
2025-05-14 2025-03-31 13F IRON MTN INC DEL COM 46284V101 70,017 -7,080 -9.18 6,024 -25.66 0.0377
2025-02-07 2024-12-31 13F IRON MTN INC DEL COM 46284V101 77,097 52,061 207.94 8,104 172.46 0.0467
2024-11-13 2024-09-30 13F IRON MTN INC DEL COM 46284V101 25,036 -1,044 -4.00 2,975 27.26 0.0171
2024-08-05 2024-06-30 13F IRON MTN INC DEL COM 46284V101 26,080 -162,368 -86.16 2,337 -84.54 0.0142
2024-05-06 2024-03-31 13F IRON MTN INC DEL COM 46284V101 188,448 144,529 329.08 15,115 391.86 0.0967
2024-02-14 2023-12-31 13F IRON MTN INC DEL COM 46284V101 43,919 21,855 99.05 3,074 134.40 0.0212
2023-11-13 2023-09-30 13F IRON MTN INC DEL COM 46284V101 22,064 0 0.00 1,312 4.63 0.0093
2023-08-08 2023-06-30 13F IRON MTN INC DEL COM 46284V101 22,064 -20,535 -48.21 1,254 -39.59 0.0091
2023-05-12 2023-03-31 13F IRON MTN INC DEL COM 46284V101 42,599 5,183 13.85 2,075 11.21 0.0144
2023-02-13 2022-12-31 13F IRON MTN INC DEL COM 46284V101 37,416 -4,304 -10.32 1,865 1.63 0.0126
2022-11-10 2022-09-30 13F IRON MTN INC DEL COM 46284V101 41,720 21,581 107.16 1,835 87.05 0.0129
2022-08-03 2022-06-30 13F IRON MTN INC COM 46284V101 20,139 2,914 16.92 981 2.83 0.0081
2022-05-13 2022-03-31 13F IRON MTN INC COM 46284V101 17,225 2,572 17.55 954 24.38 0.0065
2022-02-10 2021-12-31 13F IRON MTN INC COM 46284V101 14,653 0 0.00 767 20.41 0.0049
2021-11-09 2021-09-30 13F IRON MTN INC COM 46284V101 14,653 -14,596 -49.90 637 -48.55 0.0043
2021-07-20 2021-06-30 13F IRON MTN INC COM 46284V101 29,249 -3,572 -10.88 1,238 33.26 0.0085
2021-04-29 2021-03-31 13F IRON MTN INC COM 46284V101 32,821 0 0.00 929 -4.03 0.0077
2021-01-22 2020-12-31 13F IRON MTN INC COM 46284V101 32,821 4,457 15.71 968 27.37 0.0077
2020-10-19 2020-09-30 13F IRON MTN INC COM 46284V101 28,364 -4,231 -12.98 760 -10.69 0.0071
2020-07-23 2020-06-30 13F IRON MTN INC COM 46284V101 32,595 -64,858 -66.55 851 -71.97 0.0090
2020-05-26 2020-03-31 13F IRON MTN INC COM 46284V101 97,453 0 0.00 3,036 -2.25 0.0336
2020-02-05 2019-12-31 13F/A-1 IRON MTN INC COM 46284V101 97,453 74,754 329.33 3,106 322.59 0.0333
2020-01-21 2019-12-31 13F IRON MTN INC COM 46284V101 97,453 74,754 3 32,175.0322
2020-02-05 2019-09-30 13F/A-1 IRON MTN INC COM 46284V101 22,699 22,699 735 0.0097
2019-10-21 2019-09-30 13F IRON MTN INC COM 46284V101 22,699 22,699 1 12,567.5506
2017-02-01 2016-12-31 13F IRON MTN INC COM 46284V101 0 -16,512 -100.00 0 -100.00
2016-11-15 2016-09-30 13F IRON MTN INC COM 46284V101 16,512 16,512 0.00 620 0.0149
2015-07-29 2015-06-30 13F IRON MTN INC COM 46284V101 0 -189,898 -100.00 0 -100.00
2015-05-28 2015-03-31 13F/A-1 IRON MTN INC COM 46284V101 189,898 189,898 6,929 0.1396
2015-04-27 2015-03-31 13F IRON MTN INC COM 46284V101 189,898 6,927
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.