Iron Mountain Incorporated
MX ˙ BMV ˙ US46284V1017
SecurityMX:IRM1 / Iron Mountain Incorporated
InstitutionBridgewater Associates, LP
ManagerRay Dalio, Bob Prince
Latest Disclosed Ownership4,694 shares
Latest Disclosed Value $ 479,445
Bridgewater Associates, LP ownership in IRM1 / Iron Mountain Incorporated

On May 15, 2026 - Bridgewater Associates, LP filed a 13F-HR form disclosing ownership of 4,694 shares of Iron Mountain Incorporated (MX:IRM1) valued at $479,445 USD as of March 31, 2026. The entity filed a previous 13F-HR on May 14, 2025 disclosing 0 shares of Iron Mountain Incorporated.

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 4,694 4,694 479 0.0021
2025-05-14 2025-03-31 13F IRON MTN INC DEL COM 46284V101 0 -2,074 -100.00 0 -100.00
2025-02-13 2024-12-31 13F IRON MTN INC DEL COM 46284V101 2,074 2,074 218 0.0010
2023-05-12 2023-03-31 13F IRON MTN INC DEL COM 46284V101 0 -90,623 -100.00 0 -100.00
2023-02-13 2022-12-31 13F IRON MTN INC DEL COM 46284V101 90,623 29,163 47.45 4,518 67.17 0.0247
2022-11-10 2022-09-30 13F IRON MTN INC DEL COM 46284V101 61,460 4,276 7.48 2,702 -2.95 0.0137
2022-08-11 2022-06-30 13F IRON MTN INC COM 46284V101 57,184 8,360 17.12 2,784 2.92 0.0118
2022-05-13 2022-03-31 13F IRON MTN INC COM 46284V101 48,824 21,853 81.02 2,705 91.71 0.0109
2022-02-14 2021-12-31 13F IRON MTN INC COM 46284V101 26,971 26,971 1,411 0.0082
2020-11-13 2020-09-30 13F IRON MTN INC COM 46284V101 0 -10,480 -100.00 0 -100.00
2020-08-12 2020-06-30 13F IRON MTN INC COM 46284V101 10,480 -5,295 -33.57 274 -26.93 0.0046
2020-05-14 2020-03-31 13F IRON MTN INC COM 46284V101 15,775 15,775 50.52 375 36.86 0.0074
2020-02-13 2019-12-31 13F IRON MTN INC COM 46284V101 0 -48,484 -100.00 0 -100.00
2019-11-13 2019-09-30 13F IRON MTN INC COM 46284V101 48,484 35,573 275.52 1,570 288.61 0.0138
2019-08-13 2019-06-30 13F IRON MTN INC COM 46284V101 12,911 12,911 -73.37 404 -74.27 0.0032
2019-05-14 2019-03-31 13F IRON MTN INC COM 46284V101 0 -81,746 -100.00 0 -100.00
2019-02-13 2018-12-31 13F IRON MTN INC COM 46284V101 81,746 72,226 758.68 2,649 705.17 0.0242
2018-11-13 2018-09-30 13F IRON MTN INC COM 46284V101 9,520 -16,666 -63.64 329 -64.12 0.0034
2018-08-13 2018-06-30 13F IRON MTN INC COM 46284V101 26,186 -20,229 -43.58 917 -39.87 0.0092
2018-05-15 2018-03-31 13F IRON MTN INC COM 46284V101 46,415 46,415 77.25 1,525 66.30 0.0145
2017-11-13 2017-09-30 13F IRON MTN INC COM 46284V101 0 -6,038 -100.00 0 -100.00
2017-08-10 2017-06-30 13F IRON MTN INC COM 46284V101 6,038 6,038 207 0.0019
2016-02-11 2015-12-31 13F IRON MTN INC COM 46284V101 0 0 0 0.0000
2015-11-12 2015-09-30 13F IRON MTN INC COM 46284V101 0 -11,603 -100.00 0 -100.00
2015-08-11 2015-06-30 13F IRON MTN INC COM 46284V101 11,603 11,603 360 0.0033
2014-11-12 2014-09-30 13F IRON MTN COM 462846106 0 -18,247 -100.00 0 -100.00
2014-08-12 2014-06-30 13F IRON MTN COM 462846106 18,247 18,247 647 0.0048
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.