Iron Mountain Incorporated
MX ˙ BMV ˙ US46284V1017
SecurityMX:IRM1 / Iron Mountain Incorporated
InstitutionQuadrant Capital Group Llc
Latest Disclosed Ownership6,576 shares
Latest Disclosed Value $ 671,673
Quadrant Capital Group Llc reports 8.28% increase in ownership of IRM1 / Iron Mountain Incorporated

On May 13, 2026 - Quadrant Capital Group Llc filed a 13F-HR/A form disclosing ownership of 6,576 shares of Iron Mountain Incorporated (MX:IRM1) valued at $671,673 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 6,073 shares of Iron Mountain Incorporated. This represents a change in shares of 8.28% 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.

Upgrade to unlock premium data and export to Excel .

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)
2026-05-13 2026-03-31 13F/A-1 IRON MTN INC DEL COM 46284V101 6,576 503 8.28 672 33.40 0.0201
2026-05-11 2026-03-31 13F IRON MTN INC DEL COM 46284V101 6,576 503 49 0.0369
2026-02-12 2025-12-31 13F IRON MTN INC DEL COM 46284V101 6,073 -531 -8.04 504 -25.26 0.0152
2025-11-13 2025-09-30 13F IRON MTN INC DEL COM 46284V101 6,604 -8 -0.12 673 -0.74 0.0219
2025-08-13 2025-06-30 13F IRON MTN INC DEL COM 46284V101 6,612 759 12.97 678 34.79 0.0244
2025-05-13 2025-03-31 13F IRON MTN INC DEL COM 46284V101 5,853 4,373 295.47 504 224.52 0.0187
2025-02-13 2024-12-31 13F IRON MTN INC DEL COM 46284V101 1,480 86 6.17 156 -6.06 0.0107
2024-11-12 2024-09-30 13F IRON MTN INC DEL COM 46284V101 1,394 -79 -5.36 166 25.00 0.0115
2024-08-12 2024-06-30 13F IRON MTN INC DEL COM 46284V101 1,473 -30 -2.00 132 10.00 0.0098
2024-05-15 2024-03-31 13F IRON MTN INC DEL COM 46284V101 1,503 -49 -3.16 121 11.11 0.0095
2024-02-08 2023-12-31 13F IRON MTN INC DEL COM 46284V101 1,552 769 98.21 109 134.78 0.0093
2023-11-14 2023-09-30 13F IRON MTN INC DEL COM 46284V101 783 16 2.09 47 6.98 0.0047
2023-08-10 2023-06-30 13F IRON MTN INC DEL COM 46284V101 767 105 15.86 44 22.86 0.0043
2023-05-11 2023-03-31 13F IRON MTN INC DEL COM 46284V101 662 327 97.61 35 118.75 0.0036
2023-02-13 2022-12-31 13F IRON MTN INC DEL COM 46284V101 335 -69 -17.08 17 -11.11 0.0019
2022-11-10 2022-09-30 13F IRON MTN INC DEL COM 46284V101 404 -48 -10.62 18 -18.18 0.0024
2022-08-09 2022-06-30 13F IRON MTN INC COM 46284V101 452 -7 -1.53 22 -12.00 0.0030
2022-05-06 2022-03-31 13F IRON MTN INC COM 46284V101 459 -1 -0.22 25 4.17 0.0030
2022-02-01 2021-12-31 13F IRON MTN INC COM 46284V101 460 78 20.42 24 41.18 0.0029
2021-11-12 2021-09-30 13F IRON MTN INC COM 46284V101 382 -6 -1.55 17 6.25 0.0024
2021-08-09 2021-06-30 13F IRON MTN INC COM 46284V101 388 -279 -41.83 16 -36.00 0.0023
2021-05-12 2021-03-31 13F IRON MTN INC COM 46284V101 667 49 7.93 25 38.89 0.0041
2021-02-16 2020-12-31 13F IRON MTN INC COM 46284V101 618 349 129.74 18 157.14 0.0033
2020-11-13 2020-09-30 13F IRON MTN INC COM 46284V101 269 269 7 0.0015
2020-08-13 2020-06-30 13F Iron Mountain Com 46284V101 0 -1,970 -100.00 0 -100.00
2020-05-15 2020-03-31 13F Iron Mountain Com 46284V101 1,970 316 19.11 48 2.13 0.0080
2020-03-19 2019-12-31 13F/A-1 Iron Mountain Com 46284V101 1,654 1,047 172.49 47 193.75 0.0057
2020-02-03 2019-12-31 13F Iron Mountain Com 46284V101 1,654 1,047 47 158.8191
2019-10-24 2019-09-30 13F Iron Mountain COM 46284V101 607 -1,422 -70.08 16 -73.33 0.0025
2019-07-24 2019-06-30 13F Iron Mountain COM 46284V101 2,029 1,458 255.34 60 275.00 0.0095
2019-04-29 2019-03-31 13F Iron Mountain COM 46284V101 571 -124 -17.84 16 -11.11 0.0028
2019-01-17 2018-12-31 13F Iron Mountain COM 46284V101 695 178 34.43 18 20.00 0.0048
2018-10-29 2018-09-30 13F Iron Mountain COM 46284V101 517 -27 -4.96 15 -6.25 0.0043
2018-08-08 2018-06-30 13F Iron Mountain COM 46284V101 544 27 5.22 16 14.29 0.0056
2018-05-10 2018-03-31 13F Iron Mountain COM 46284V101 517 -142 -21.55 14 -36.36 0.0051
2018-01-31 2017-12-31 13F Iron Mountain Inc PA COM 46284V101 659 0 0.00 22 -4.35 0.0088
2017-10-13 2017-09-30 13F Iron Mountain Inc PA COM 46284V101 659 0 0.00 23 35.29 0.0095
2017-08-14 2017-06-30 13F Iron Mountain Inc PA COM 46284V101 659 162 32.60 17 21.43 0.0075
2017-04-10 2017-03-31 13F Iron Mountain Inc PA COM 46284V101 497 0 0.00 14 7.69 0.0062
2017-01-11 2016-12-31 13F Iron Mountain Inc PA COM 46284V101 497 -29 -5.51 13 -18.75 0.0065
2016-10-25 2016-09-30 13F Iron Mountain Inc PA COM 46284V101 526 -22 -4.01 16 -11.11 0.0104
2016-07-28 2016-06-30 13F Iron Mountain Inc PA COM 46284V101 548 13 2.43 18 20.00 0.0124
2016-04-27 2016-03-31 13F Iron Mountain Inc PA COM 46284V101 535 381 247.40 15 400.00 0.0097
2016-01-28 2015-12-31 13F Iron Mountain Inc PA COM 46284V101 154 -212 -57.92 3 -70.00 0.0021
2015-10-28 2015-09-30 13F Iron Mountain Inc PA COM 46284V101 366 20 5.78 10 0.00 0.0069
2015-08-12 2015-06-30 13F Iron Mountain Inc PA COM 46284V101 346 346 10 0.0064
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.