Iron Mountain Incorporated
MX ˙ BMV ˙ US46284V1017
SecurityMX:IRM1 / Iron Mountain Incorporated
InstitutionGotham Asset Management, LLC
ManagerJoel Greenblatt
Latest Disclosed Ownership39,732 shares
Latest Disclosed Value $ 4,058,226
Gotham Asset Management, LLC reports 3.07% increase in ownership of IRM1 / Iron Mountain Incorporated

On May 15, 2026 - Gotham Asset Management, LLC filed a 13F-HR form disclosing ownership of 39,732 shares of Iron Mountain Incorporated (MX:IRM1) valued at $4,058,226 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 38,547 shares of Iron Mountain Incorporated. This represents a change in shares of 3.07% 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)
2026-05-15 2026-03-31 13F IRON MTN INC DEL COM 46284V101 39,732 1,185 3.07 4,058 26.93 0.0124
2026-02-17 2025-12-31 13F IRON MTN INC DEL COM 46284V101 38,547 -45,377 -54.07 3,197 -62.63 0.0117
2025-11-14 2025-09-30 13F IRON MTN INC DEL COM 46284V101 83,924 -10,904 -11.50 8,555 -12.04 0.0372
2025-08-14 2025-06-30 13F IRON MTN INC DEL COM 46284V101 94,828 29,144 44.37 9,727 72.11 0.0582
2025-05-15 2025-03-31 13F IRON MTN INC DEL COM 46284V101 65,684 -20,873 -24.11 5,651 -37.89 0.0472
2025-02-14 2024-12-31 13F IRON MTN INC DEL COM 46284V101 86,557 5,153 6.33 9,098 -5.94 0.0863
2024-11-14 2024-09-30 13F IRON MTN INC DEL COM 46284V101 81,404 10,404 14.65 9,673 52.02 0.1001
2024-08-14 2024-06-30 13F IRON MTN INC DEL COM 46284V101 71,000 21,732 44.11 6,363 61.05 0.0824
2024-05-15 2024-03-31 13F IRON MTN INC DEL COM 46284V101 49,268 6,762 15.91 3,952 32.85 0.0597
2024-02-14 2023-12-31 13F IRON MTN INC DEL COM 46284V101 42,506 -11,536 -21.35 2,975 -7.41 0.0552
2023-11-14 2023-09-30 13F IRON MTN INC DEL COM 46284V101 54,042 11,059 25.73 3,213 31.53 0.0664
2023-08-14 2023-06-30 13F IRON MTN INC DEL COM 46284V101 42,983 -2,882 -6.28 2,442 0.66 0.0531
2023-05-15 2023-03-31 13F IRON MTN INC DEL COM 46284V101 45,865 -3,124 -6.38 2,427 -0.66 0.0588
2023-02-14 2022-12-31 13F IRON MTN INC DEL COM 46284V101 48,989 9,216 23.17 2,442 39.62 0.0687
2022-11-14 2022-09-30 13F IRON MTN INC DEL COM 46284V101 39,773 17,450 78.17 1,749 60.90 0.0524
2022-08-15 2022-06-30 13F IRON MTN INC COM 46284V101 22,323 1,924 9.43 1,087 -3.81 0.0349
2022-05-16 2022-03-31 13F IRON MTN INC COM 46284V101 20,399 3,272 19.10 1,130 26.12 0.0350
2022-02-14 2021-12-31 13F IRON MTN INC COM 46284V101 17,127 -13,428 -43.95 896 -32.53 0.0289
2021-11-15 2021-09-30 13F IRON MTN INC COM 46284V101 30,555 11,578 61.01 1,328 65.38 0.0539
2021-08-16 2021-06-30 13F IRON MTN INC COM 46284V101 18,977 18,977 803 0.0340
2021-02-16 2020-12-31 13F IRON MTN INC COM 46284V101 0 -7,999 -100.00 0 -100.00
2020-11-16 2020-09-30 13F IRON MTN INC COM 46284V101 7,999 -19,376 -70.78 214 -70.03 0.0069
2020-08-13 2020-06-30 13F IRON MTN INC COM 46284V101 27,375 27,375 242.23 714 233.64 0.0214
2020-05-15 2020-03-31 13F IRON MTN INC COM 46284V101 0 -11,712 -100.00 0 -100.00
2020-02-14 2019-12-31 13F IRON MTN INC COM 46284V101 11,712 11,712 373 0.0068
2019-11-14 2019-09-30 13F IRON MTN INC COM 46284V101 0 -9,642 -100.00 0 -100.00
2019-08-14 2019-06-30 13F IRON MTN INC COM 46284V101 9,642 9,642 302 0.0048
2017-11-14 2017-09-30 13F IRON MTN INC COM 46284V101 0 -34,589 -100.00 0 -100.00
2017-08-14 2017-06-30 13F IRON MTN INC COM 46284V101 34,589 495 1.45 1,188 -2.30 0.0167
2017-05-15 2017-03-31 13F IRON MTN INC COM 46284V101 34,094 34,094 -1.43 1,216 2.36 0.0154
2016-11-14 2016-09-30 13F IRON MTN INC COM 46284V101 0 -5,179 -100.00 0 -100.00
2016-08-15 2016-06-30 13F IRON MTN INC COM 46284V101 5,179 -3,019 -36.83 206 -25.90 0.0025
2016-05-16 2016-03-31 13F IRON MTN INC COM 46284V101 8,198 -43,095 -84.02 278 -79.93 0.0031
2016-02-16 2015-12-31 13F IRON MTN INC COM 46284V101 51,293 51,293 525.68 1,385 398.20 0.0150
2013-11-14 2013-09-30 13F IRON MTN COM 462846106 0 -14,594 -100.00 0 -100.00
2013-08-15 2013-06-30 13F/A-1 IRON MTN COM 462846106 14,594 14,594 388 0.0166
2013-08-14 2013-06-30 13F IRON MTN COM 462846106 14,594 388 0.0165
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.