Iron Mountain Incorporated
DE ˙ DB ˙ US46284V1017
108,60 € ↓ -0,40 (-0,37%)
2026-05-29
DEL PRIS
SecurityDE:I5M / Iron Mountain Incorporated
InstitutionTcw Group Inc
Latest Disclosed Ownership135,359 shares
Latest Disclosed Value $ 13,825,568
Tcw Group Inc reports 2.33% increase in ownership of I5M / Iron Mountain Incorporated

On May 14, 2026 - Tcw Group Inc filed a 13F-HR form disclosing ownership of 135,359 shares of Iron Mountain Incorporated (DE:I5M) valued at $12,017,172 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 132,280 shares of Iron Mountain Incorporated. This represents a change in shares of 2.33% during the quarter. The current value of the position is $14,699,987 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)
2026-05-14 2026-03-31 13F IRON MTN INC DEL COM 46284V101 135,359 3,079 2.33 13,826 26.00 0.0554
2026-02-17 2025-12-31 13F IRON MTN INC DEL COM 46284V101 132,280 51,257 63.26 10,973 32.85 0.0786
2025-11-14 2025-09-30 13F IRON MTN INC DEL COM 46284V101 81,023 81,023 8,259 0.0692
2022-10-27 2022-09-30 13F IRON MTN INC COM 46284V101 0 -343,178 -100.00 0 -100.00
2022-07-19 2022-06-30 13F IRON MTN INC COM 46284V101 343,178 108,583 46.29 16,709 28.54 0.2187
2022-04-19 2022-03-31 13F IRON MTN INC COM 46284V101 234,595 -9,390 -3.85 12,999 1.81 0.1240
2022-01-26 2021-12-31 13F IRON MTN INC COM 46284V101 243,985 12,621 5.46 12,768 27.01 0.1050
2021-10-26 2021-09-30 13F IRON MTN INC COM 46284V101 231,364 -64,104 -21.70 10,053 -19.60 0.0259
2021-07-23 2021-06-30 13F IRON MTN INC COM 46284V101 295,468 49,085 19.92 12,504 37.14 0.1083
2021-05-05 2021-03-31 13F IRON MTN INC COM 46284V101 246,383 217,845 763.35 9,118 984.19 0.0874
2021-02-02 2020-12-31 13F IRON MTN INC COM 46284V101 28,538 8,152 39.99 841 54.03 0.0073
2020-10-30 2020-09-30 13F IRON MTN INC COM 46284V101 20,386 20,386 546 0.0060
2017-05-11 2017-03-31 13F IRON MTN INC COM 46284V101 0 -18,050 -100.00 0 -100.00
2017-02-10 2016-12-31 13F IRON MTN INC COM 46284V101 18,050 -50 -0.28 586 -13.70 0.0044
2016-11-14 2016-09-30 13F IRON MTN INC COM 46284V101 18,100 550 3.13 679 -2.86 0.0052
2016-08-12 2016-06-30 13F/A-1 IRON MTN INC COM 46284V101 17,550 4,100 30.48 699 53.29 0.0053
2016-08-11 2016-06-30 13F IRON MTN INC COM 46284V101 17,550 699
2016-05-16 2016-03-31 13F IRON MTN INC COM 46284V101 13,450 150 1.13 456 27.02 0.0033
2016-02-16 2015-12-31 13F IRON MTN INC COM 46284V101 13,300 150 1.14 359 -12.01 0.0026
2015-11-13 2015-09-30 13F IRON MTN INC COM 46284V101 13,150 302 2.35 408 2.51 0.0029
2015-08-12 2015-06-30 13F IRON MTN INC COM 46284V101 12,848 -39,889 -75.64 398 -79.31 0.0026
2015-05-13 2015-03-31 13F IRON MTN INC COM 46284V101 52,737 550 1.05 1,924 -4.66 0.0092
2015-02-13 2014-12-31 13F IRON MTN COM 462846106 52,187 -31,945 -37.97 2,018 -26.54 0.0084
2014-11-14 2014-09-30 13F IRON MTN COM 462846106 84,132 -1,509 -1.76 2,747 -9.52 0.0110
2014-08-14 2014-06-30 13F IRON MTN COM 462846106 85,641 900 1.06 3,036 29.97 0.0125
2014-05-13 2014-03-31 13F IRON MTN COM 462846106 84,741 600 0.71 2,336 -8.50 0.0097
2014-02-18 2013-12-31 13F/A-1 IRON MTN COM 462846106 84,141 100 0.12 2,553 12.42 0.0108
2014-02-14 2013-12-31 13F IRON MTN COM 462846106 2,553 84,141
2013-11-14 2013-09-30 13F IRON MTN COM 462846106 84,041 1,750 2.13 2,271 3.70 0.0105
2013-08-14 2013-06-30 13F/A-1 IRON MTN COM 462846106 82,291 82,291 2,190 0.0108
2013-08-14 2013-06-30 13F IRON MTN COM 462846106 82,291 2,190
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.