Iron Mountain Incorporated
MX ˙ BMV ˙ US46284V1017
SecurityMX:IRM1 / Iron Mountain Incorporated
InstitutionWellington Shields & Co., LLC
Latest Disclosed Ownership10,643 shares
Latest Disclosed Value $ 1,087,076
Wellington Shields & Co., LLC ownership in IRM1 / Iron Mountain Incorporated

On May 4, 2026 - Wellington Shields & Co., LLC filed a 13F-HR form disclosing ownership of 10,643 shares of Iron Mountain Incorporated (MX:IRM1) valued at $1,087,076 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 9, 2026 disclosing 10,643 shares of Iron Mountain Incorporated. This represents a change in shares of 0.00% 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)
2026-05-04 2026-03-31 13F IRON MTN INC DEL COM REIT 46284V101 10,643 0 0.00 1,087 23.24 0.2770
2026-02-09 2025-12-31 13F IRON MTN INC DEL COM REIT 46284V101 10,643 0 0.00 883 -18.63 0.2178
2025-11-05 2025-09-30 13F IRON MTN INC DEL COM REIT 46284V101 10,643 0 0.00 1,085 -0.64 0.2830
2025-08-05 2025-06-30 13F IRON MTN INC DEL COM REIT 46284V101 10,643 0 0.00 1,092 19.23 0.3090
2025-05-08 2025-03-31 13F IRON MTN INC DEL COM REIT 46284V101 10,643 0 0.00 916 -18.16 0.2866
2025-02-10 2024-12-31 13F IRON MTN INC DEL COM REIT 46284V101 10,643 0 0.00 1,119 -11.55 0.3430
2024-11-13 2024-09-30 13F IRON MTN INC DEL COM REIT 46284V101 10,643 0 0.00 1,265 32.63 0.3845
2024-08-07 2024-06-30 13F IRON MTN INC DEL COM REIT 46284V101 10,643 0 0.00 954 11.72 0.3107
2024-05-23 2024-03-31 13F/A-2 IRON MTN INC DEL COM REIT 46284V101 10,643 0 0.00 854 14.65 0.2861
2024-05-23 2024-03-31 13F/A-1 IRON MTN INC DEL COM REIT 46284V101 10,643 0 745 0.2748
2024-05-03 2024-03-31 13F IRON MTN INC DEL COM REIT 46284V101 10,643 0 854 0.2859
2024-05-23 2023-12-31 13F/A-1 IRON MTN INC DEL COM REIT 46284V101 10,643 -390 -3.53 745 13.59 0.2748
2024-02-09 2023-12-31 13F IRON MTN INC DEL COM REIT 46284V101 10,643 -390 745 0.1769
2023-11-14 2023-09-30 13F IRON MTN INC DEL COM REIT 46284V101 11,033 2,500 29.30 656 35.33 0.1640
2023-08-11 2023-06-30 13F IRON MTN INC DEL COM REIT 46284V101 8,533 -2,950 -25.69 485 -20.26 0.1140
2023-05-11 2023-03-31 13F IRON MTN INC DEL COM REIT 46284V101 11,483 0 0.00 608 6.12 0.1362
2023-02-15 2022-12-31 13F IRON MTN INC DEL COM REIT 46284V101 11,483 0 0.00 572 13.27 0.1301
2022-11-14 2022-09-30 13F IRON MTN INC DEL COM REIT 46284V101 11,483 0 0.00 505 -9.66 0.2203
2022-08-12 2022-06-30 13F IRON MTN INC DEL COM REIT 46284V101 11,483 400 3.61 559 -8.96 0.1355
2022-05-09 2022-03-31 13F IRON MOUNTAIN INC REIT COM 46284V101 11,083 -3,155 -22.16 614 -17.58 0.2019
2022-02-15 2021-12-31 13F IRON MOUNTAIN INC REIT COM 46284V101 14,238 528 3.85 745 25.00 0.1488
2021-11-10 2021-09-30 13F IRON MOUNTAIN INC REIT COM 46284V101 13,710 10 0.07 596 2.76 0.2079
2021-08-12 2021-06-30 13F IRON MOUNTAIN INC REIT COM 46284V101 13,700 200 1.48 580 16.00 0.1914
2021-05-12 2021-03-31 13F IRON MOUNTAIN INC REIT COM 46284V101 13,500 13,500 500 0.1792
2019-08-08 2019-06-30 13F IRON MOUNTAIN INC REIT COM 46284V101 0 -5,775 -100.00 0 -100.00
2019-05-10 2019-03-31 13F IRON MOUNTAIN INC REIT COM 46284V101 5,775 -8,225 -58.75 205 -51.76 0.1044
2014-02-11 2013-12-31 13F IRON MTN INC COM COM 462846106 14,000 14,000 425 0.0763
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.