Iron Mountain Incorporated
MX ˙ BMV ˙ US46284V1017
SecurityMX:IRM1 / Iron Mountain Incorporated
InstitutionKentucky Retirement Systems
Latest Disclosed Ownership14,051 shares
Latest Disclosed Value $ 426
Kentucky Retirement Systems reports 23.72% decrease in ownership of IRM1 / Iron Mountain Incorporated

On May 19, 2026 - Kentucky Retirement Systems filed a 13F-HR form disclosing ownership of 14,051 shares of Iron Mountain Incorporated (MX:IRM1) valued at $426 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 10, 2026 disclosing 18,420 shares of Iron Mountain Incorporated. This represents a change in shares of -23.72% 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)
2026-05-19 2026-03-31 13F IRON MTN COM 462846106 14,051 -4,369 -23.72 0 -100.00 0.0312
2026-02-10 2025-12-31 13F IRON MTN INC DEL COM 46284V101 18,420 0 0.00 1,528 -18.65 0.0414
2025-11-13 2025-09-30 13F IRON MTN INC DEL COM 46284V101 18,420 -234 -1.25 1,878 -1.88 0.0519
2025-08-20 2025-06-30 13F IRON MTN INC DEL COM 46284V101 18,654 -1,222 -6.15 1,913 11.87 0.0560
2025-04-22 2025-03-31 13F IRON MTN INC DEL COM 46284V101 19,876 -282 -1.40 1,710 -19.26 0.0521
2025-02-03 2024-12-31 13F IRON MTN INC DEL COM 46284V101 20,158 -277 -1.36 2,119 -12.77 0.0625
2024-11-06 2024-09-30 13F IRON MTN INC DEL COM 46284V101 20,435 -1,654 -7.49 2,428 22.69 0.0716
2024-08-12 2024-06-30 13F IRON MTN INC DEL COM 46284V101 22,089 -86 -0.39 1,980 11.30 0.0573
2024-05-15 2024-03-31 13F IRON MTN INC DEL COM 46284V101 22,175 -1,187 -5.08 1,779 8.81 0.0531
2024-02-08 2023-12-31 13F IRON MTN INC DEL COM 46284V101 23,362 -311 -1.31 1,635 16.13 0.0510
2023-10-12 2023-09-30 13F IRON MTN INC DEL COM 46284V101 23,673 226 0.96 1,407 140,600.00 0.0489
2023-08-07 2023-06-30 13F IRON MTN INC DEL COM 46284V101 23,447 461 2.01 1 0.00 0.0446
2023-05-10 2023-03-31 13F IRON MTN INC DEL COM 46284V101 22,986 132 0.58 1 0.00 0.0448
2023-02-06 2022-12-31 13F IRON MTN INC DEL COM 46284V101 22,854 100 0.44 1 -99.90 0.0449
2022-11-16 2022-09-30 13F IRON MTN INC DEL COM 46284V101 22,754 1,189 5.51 1,000 -4.76 0.0424
2022-08-08 2022-06-30 13F IRON MTN INC COM 46284V101 21,565 3,109 16.85 1,050 2.64 0.0443
2022-05-09 2022-03-31 13F IRON MTN INC COM 46284V101 18,456 1,515 8.94 1,023 15.33 0.0419
2022-02-04 2021-12-31 13F IRON MTN INC COM 46284V101 16,941 -743 -4.20 887 15.49 0.0360
2021-11-17 2021-09-30 13F IRON MTN INC COM 46284V101 17,684 871 5.18 768 7.87 0.0361
2021-08-12 2021-06-30 13F IRON MTN INC COM 46284V101 16,813 -1,022 -5.73 712 7.88 0.0337
2021-05-14 2021-03-31 13F IRON MTN INC COM 46284V101 17,835 -610 -3.31 660 21.32 0.0323
2021-02-11 2020-12-31 13F IRON MTN INC COM 46284V101 18,445 1,645 9.79 544 20.89 0.0281
2020-11-12 2020-09-30 13F IRON MTN INC COM 46284V101 16,800 773 4.82 450 7.66 0.0278
2020-08-12 2020-06-30 13F IRON MTN INC COM 46284V101 16,027 -3,584 -18.28 418 -10.49 0.0293
2020-05-01 2020-03-31 13F IRON MTN INC COM 46284V101 19,611 4,839 32.76 467 -0.85 0.0319
2020-02-18 2019-12-31 13F IRON MTN INC COM 46284V101 14,772 60 0.41 471 -1.26 0.0343
2019-11-05 2019-09-30 13F IRON MTN INC COM 46284V101 14,712 1,352 10.12 477 14.11 0.0379
2019-08-07 2019-06-30 13F/A-1 IRON MTN INC COM 46284V101 13,360 840 6.71 418 -5.86 0.0369
2019-08-07 2019-06-30 13F IRON MTN INC COM 46284V101 13,360 840 418
2019-05-22 2019-03-31 13F IRON MTN INC COM 46284V101 12,520 70 0.56 444 9.90 0.0430
2019-02-25 2018-12-31 13F IRON MTN INC COM 46284V101 12,450 265 2.17 404 -4.04 0.0443
2018-11-19 2018-09-30 13F/A-1 IRON MTN INC COM 46284V101 12,185 236 1.98 421 0.72 0.0402
2018-11-16 2018-09-30 13F IRON MTN COM 462846106 14,051 2,102 426
2018-08-13 2018-06-30 13F IRON MTN INC COM 46284V101 11,949 -2,739 -18.65 418 -13.46 0.0428
2018-05-07 2018-03-31 13F IRON MTN INC COM 46284V101 14,688 -1,773 -10.77 483 -22.22 0.0412
2018-02-13 2017-12-31 13F IRON MTN INC COM 46284V101 16,461 1,379 9.14 621 5.79 0.0442
2017-11-08 2017-09-30 13F IRON MTN INC COM 46284V101 15,082 -664 -4.22 587 8.50 0.0443
2017-08-18 2017-06-30 13F IRON MTN INC COM 46284V101 15,746 21 0.13 541 -3.57 0.0407
2017-05-24 2017-03-31 13F IRON MTN INC COM 46284V101 15,725 -2,054 -11.55 561 -2.77 0.0432
2017-02-24 2016-12-31 13F IRON MTN INC COM 46284V101 17,779 -2,341 -11.64 577 -23.58 0.0413
2016-11-30 2016-09-30 13F IRON MTN INC COM 46284V101 20,120 -205 -1.01 755 -6.79 0.0502
2016-09-12 2016-06-30 13F IRON MTN INC COM 46284V101 20,325 2,642 14.94 810 35.00 0.0524
2016-06-09 2016-03-31 13F IRON MTN INC COM 46284V101 17,683 3,088 21.16 600 52.28 0.0364
2016-02-22 2015-12-31 13F IRON MTN INC COM 46284V101 14,595 1,431 10.87 394 -3.43 0.0290
2015-11-18 2015-09-30 13F IRON MTN INC COM 46284V101 13,164 520 4.11 408 4.08 0.0351
2015-08-26 2015-06-30 13F IRON MTN INC COM 46284V101 12,644 60 0.48 392 -14.60 0.0319
2015-05-29 2015-03-31 13F IRON MTN INC COM 46284V101 12,584 -1,277 -9.21 459 -14.37 0.0373
2015-03-04 2014-12-31 13F IRON MTN COM 462846106 13,861 490 3.66 536 22.65 0.0395
2014-12-12 2014-09-30 13F IRON MTN COM 462846106 13,371 -757 -5.36 437 12.05 0.0321
2014-05-22 2014-03-31 13F IRON MTN COM 462846106 14,128 77 0.55 390 -8.45 0.0282
2014-02-13 2013-12-31 13F IRON MTN COM 462846106 14,051 -77 -0.55 426 11.52 0.0312
2013-11-15 2013-09-30 13F IRON MTN COM 462846106 14,128 14,128 382 0.0308
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.