Iron Mountain Incorporated
US ˙ NYSE ˙ US46284V1017

SecurityIRM / Iron Mountain Incorporated
InstitutionLazard Asset Management Llc
Latest Disclosed Ownership0 shares
Latest Disclosed Value $ 0
Lazard Asset Management Llc closes position in IRM / Iron Mountain Incorporated

On November 14, 2025 - Lazard Asset Management Llc filed a 13F-HR form disclosing ownership of 0 shares of Iron Mountain Incorporated (US:IRM) valued at $0 USD as of September 30, 2025. The entity filed a previous 13F-HR on August 14, 2025 disclosing 210 shares of Iron Mountain Incorporated. The current value of the position is $0 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)
2025-11-14 2025-09-30 13F IRON MOUNT Common Stock 46284V101 0 -100.00 0
2025-08-14 2025-06-30 13F IRON MOUNT Common Stock 46284V101 210 -283 -57.40 0 0.0000
2025-05-15 2025-03-31 13F IRON MOUNT Common Stock 46284V101 493 -524 -51.52 0 0.0001
2025-02-14 2024-12-31 13F IRON MOUNT Common Stock 46284V101 1,017 10 0.99 0 0.0002
2024-11-14 2024-09-30 13F IRON MOUNT Common Stock 46284V101 1,007 -1,117 -52.59 0 0.0002
2024-08-14 2024-06-30 13F IRON MOUNT Common Stock 46284V101 2,124 -156,126 -98.66 0 -100.00 0.0002
2024-07-09 2024-03-31 13F/A-1 IRON MOUNT Common Stock 46284V101 158,250 -2,981 -1.85 13 9.09 0.0154
2024-05-14 2024-03-31 13F IRON MOUNT Common Stock 46284V101 158,250 -2,981 13 0.0154
2024-02-14 2023-12-31 13F IRON MOUNT Common Stock 46284V101 161,231 -45,725 -22.09 11 -8.33 0.0143
2023-11-14 2023-09-30 13F IRON MOUNT Common Stock 46284V101 206,956 -37,351 -15.29 12 -7.69 0.0167
2023-08-15 2023-06-30 13F IRON MOUNT Common Stock 46284V101 244,307 8,640 3.67 14 8.33 0.0171
2023-05-15 2023-03-31 13F IRON MOUNT Common Stock 46284V101 235,667 225,661 2,255.26 12 -97.59 0.0163
2023-02-15 2022-12-31 13F IRON MOUNT Common Stock 46284V101 10,006 83 0.84 498 14.22 0.0007
2022-11-14 2022-09-30 13F IRON MOUNT Common Stock 46284V101 9,923 -121 -1.20 436 -10.66 0.0006
2022-08-09 2022-06-30 13F IRON MOUNT Common Stock 46284V101 10,044 -9,287 -48.04 488 -54.44 0.0007
2022-05-13 2022-03-31 13F IRON MOUNT Common Stock 46284V101 19,331 17,665 1,060.32 1,071 1,131.03 0.0012
2022-02-09 2021-12-31 13F IRON MOUNT Common Stock 46284V101 1,666 102 6.52 87 29.85 0.0001
2021-11-15 2021-09-30 13F IRON MOUNT Common Stock 46284V101 1,564 138 9.68 67 11.67 0.0001
2021-08-12 2021-06-30 13F IRON MOUNT Common Stock 46284V101 1,426 200 16.31 60 33.33 0.0001
2021-05-14 2021-03-31 13F IRON MOUNT Common Stock 46284V101 1,226 104 9.27 45 36.36 0.0001
2021-02-11 2020-12-31 13F IRON MOUNT Common Stock 46284V101 1,122 -97 -7.96 33 3.13 0.0000
2020-11-13 2020-09-30 13F IRON MOUNT Common Stock 46284V101 1,219 -10,287 -89.41 32 -89.30 0.0000
2020-08-13 2020-06-30 13F IRON MOUNT Common Stock 46284V101 11,506 -27,296 -70.35 299 -67.57 0.0005
2020-05-14 2020-03-31 13F IRON MOUNT Common Stock 46284V101 38,802 38,402 9,600.50 922 7,583.33 0.0017
2020-02-13 2019-12-31 13F IRON MOUNT Common Stock 46284V101 400 400 12 0.0000
2019-08-30 2018-06-30 13F/A-1 IRON MOUNT Common Stock 46284V101 0 -7,000 -100.00 0 -100.00
2019-08-28 2018-03-31 13F/A-1 IRON MOUNT Common Stock 46284V101 7,000 -400 -5.41 230 -17.56 0.0004
2018-05-14 2018-03-31 13F IRON MOUNT Common Stock 46284V101 7,000 -400 230
2019-08-28 2017-12-31 13F/A-1 IRON MOUNT Common Stock 46284V101 7,400 7,400 279 0.0005
2018-02-13 2017-12-31 13F IRON MOUNT Common Stock 46284V101 7,400 7,400 279
2019-08-19 2017-06-30 13F/A-1 IRON MOUNT Common Stock 46284V101 0 -3,811 -100.00 0 -100.00
2019-08-13 2017-03-31 13F/A-1 IRON MOUNT Common Stock 46284V101 3,811 800 26.57 135 39.18 0.0003
2017-05-12 2017-03-31 13F IRON MOUNT Common Stock 46284V101 3,811 800 135
2019-07-30 2016-12-31 13F/A-1 IRON MOUNT Common Stock 46284V101 3,011 181 6.40 97 -8.49 0.0002
2017-02-13 2016-12-31 13F IRON MOUNT Common Stock 46284V101 3,011 181 97
2019-08-07 2016-09-30 13F/A-1 IRON MOUNT Common Stock 46284V101 2,830 -412,181 -99.32 106 -99.36 0.0002
2016-11-14 2016-09-30 13F IRON MOUNT Common Stock 46284V101 2,830 -412,131 106
2019-07-29 2016-06-30 13F/A-1 IRON MOUNT Common Stock 46284V101 415,011 415,011 16,529 0.0349
2016-08-15 2016-06-30 13F IRON MOUNT Common Stock 46284V101 414,961 414,961 16,527
2015-11-13 2015-09-30 13F IRON MOUNT Common Stock 46284V101 0 0 0 0.0000
2019-07-08 2015-06-30 13F/A-1 IRON MOUNT Common Stock 46284V101 0 -127,578 -100.00 0 -100.00
2015-06-09 2015-03-31 13F/A-1 IRON MOUNT Common Stock 46284V101 127,578 -212,892 -62.53 4,654 -64.64 0.0100
2015-05-15 2015-03-31 13F IRON MOUNT Common Stock 46284V101 127,578 4,654
2019-08-29 2014-12-31 13F/A-3 IRON MTN Common Stock 462846106 340,470 340,470 13,162 0.0281
2015-02-12 2014-12-31 13F IRON MTN Common Stock 462846106 340,470 13,162 0.0326
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.