Iron Mountain Incorporated
US ˙ NYSE ˙ US46284V1017

SecurityIRM / Iron Mountain Incorporated
InstitutionRegions Financial Corp
Latest Disclosed Ownership39,516 shares
Latest Disclosed Value $ 4,036,165
Regions Financial Corp reports 81.59% decrease in ownership of IRM / Iron Mountain Incorporated

On May 5, 2026 - Regions Financial Corp filed a 13F-HR form disclosing ownership of 39,516 shares of Iron Mountain Incorporated (US:IRM) valued at $4,036,164 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 27, 2026 disclosing 214,642 shares of Iron Mountain Incorporated. This represents a change in shares of -81.59% during the quarter. The current value of the position is $5,145,378 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)
2026-05-05 2026-03-31 13F IRON MTN INC DEL COM 46284V101 39,516 -175,126 -81.59 4,036 -77.33 0.0228
2026-01-27 2025-12-31 13F IRON MTN INC DEL COM 46284V101 214,642 -37,139 -14.75 17,805 -30.63 0.1140
2025-11-19 2025-09-30 13F/A-1 IRON MTN INC DEL COM 46284V101 251,781 3,495 1.41 25,667 0.79 0.1672
2025-11-19 2025-09-30 13F IRON MTN INC DEL COM 46284V101 251,781 3,495 25,667 0.1478
2025-07-29 2025-06-30 13F IRON MTN INC DEL COM 46284V101 248,286 7,010 2.91 25,467 22.67 0.1754
2025-05-08 2025-03-31 13F IRON MTN INC DEL COM 46284V101 241,276 10,500 4.55 20,759 -14.42 0.1547
2025-02-14 2024-12-31 13F Iron Mountain COM 46284V101 230,776 12,315 5.64 24,257 -6.56 0.1782
2024-11-14 2024-09-30 13F Iron Mountain COM 46284V101 218,461 218,461 25,960 0.1868
2019-07-19 2019-06-30 13F Iron Mountain COM 46284V101 0 -700 -100.00 0 -100.00
2019-04-19 2019-03-31 13F Iron Mountain COM 46284V101 700 700 25 0.0003
2018-10-22 2018-09-30 13F Iron Mountain COM 46284V101 0 -55 -100.00 0 -100.00
2018-07-26 2018-06-30 13F Iron Mountain COM 46284V101 55 -345 -86.25 2 -84.62 0.0000
2018-04-18 2018-03-31 13F Iron Mountain COM 46284V101 400 400 13 0.0001
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.