Iron Mountain Incorporated
US ˙ NYSE ˙ US46284V1017

SecurityIRM / Iron Mountain Incorporated
InstitutionCoreFirst Bank & Trust
Latest Disclosed Ownership22,629 shares
Latest Disclosed Value $ 2,311,326
CoreFirst Bank & Trust reports 0.92% decrease in ownership of IRM / Iron Mountain Incorporated

On June 3, 2026 - CoreFirst Bank & Trust filed a 13F-HR form disclosing ownership of 22,629 shares of Iron Mountain Incorporated (US:IRM) valued at $2,311,326 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 22,839 shares of Iron Mountain Incorporated. This represents a change in shares of -0.92% during the quarter. The current value of the position is $2,895,381 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)
2026-06-03 2026-03-31 13F Iron Mountain Inc Com 46284V101 22,629 -210 -0.92 2,311 22.02 0.7806
2026-02-11 2025-12-31 13F Iron Mountain Inc Com 46284V101 22,839 -1,240 -5.15 1,894 -22.82 1.0244
2025-11-13 2025-09-30 13F Iron Mountain Inc Com 46284V101 24,079 -755 -3.04 2,455 -3.65 0.8451
2025-08-14 2025-06-30 13F Iron Mountain Inc Com 46284V101 24,834 -240 -0.96 2,547 18.08 1.4385
2025-04-29 2025-03-31 13F Iron Mountain Inc Com 46284V101 25,074 -100 -0.40 2,157 -18.48 1.3870
2025-02-11 2024-12-31 13F Iron Mountain Inc Com 46284V101 25,174 -1,440 -5.41 2,646 -16.32 1.5728
2025-02-11 2024-09-30 13F Iron Mountain Inc Com 46284V101 26,614 -400 -1.48 3,163 30.66 1.8271
2024-08-14 2024-06-30 13F Iron Mountain Inc Com 46284V101 27,014 -450 -1.64 2,421 9.90 1.6290
2024-05-15 2024-03-31 13F Iron Mountain Inc Com 46284V101 27,464 -150 -0.54 2,203 13.98 1.3773
2024-03-18 2023-12-31 13F Iron Mountain Inc Com 46284V101 27,614 -1,756 -5.98 1,932 10.65 1.2845
2023-12-18 2023-09-30 13F Iron Mountain Inc Com 46284V101 29,370 -200 -0.68 1,746 3.93 1.2401
2023-08-07 2023-06-30 13F Iron Mountain Inc Com 46284V101 29,570 0 0.00 1,680 7.42 1.1824
2023-05-15 2023-03-31 13F Iron Mountain Inc Com 46284V101 29,570 -2,430 -7.59 1,565 -1.94 1.1387
2023-02-16 2022-12-31 13F Iron Mountain Inc Com 46284V101 32,000 0 0.00 1,595 13.36 1.2100
2022-11-16 2022-09-30 13F Iron Mountain Inc Com 46284V101 32,000 0 0.00 1,407 -9.69 1.2138
2022-08-16 2022-06-30 13F Iron Mtn Inc Com 46284V101 32,000 -1,790 -5.30 1,558 -16.77 1.2305
2022-05-16 2022-03-31 13F Iron Mtn Inc Com 46284V101 33,790 -50 -0.15 1,872 5.70 1.2804
2022-02-10 2021-12-31 13F Iron Mtn Inc Com 46284V101 33,840 -240 -0.70 1,771 19.58 1.1454
2021-11-15 2021-09-30 13F Iron Mtn Inc Com 46284V101 34,080 -5,800 -14.54 1,481 -12.21 1.0265
2021-08-17 2021-06-30 13F Iron Mtn Inc Com 46284V101 39,880 454 1.15 1,687 15.55 1.1481
2021-05-18 2021-03-31 13F Iron Mtn Inc Com 46284V101 39,426 0 0.00 1,460 25.54 1.0028
2021-02-16 2020-12-31 13F Iron Mtn Inc Com 46284V101 39,426 39,426 1,163 0.8620
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.