Iron Mountain Incorporated
MX ˙ BMV ˙ US46284V1017
SecurityMX:IRM1 / Iron Mountain Incorporated
InstitutionHighTower Advisors, LLC
Latest Disclosed Ownership105,660 shares
Latest Disclosed Value $ 10,791,993
HighTower Advisors, LLC ownership in IRM1 / Iron Mountain Incorporated

On May 5, 2026 - HighTower Advisors, LLC filed a 13F-HR form disclosing ownership of 105,660 shares of Iron Mountain Incorporated (MX:IRM1) valued at $10,791,993 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 6, 2026 disclosing 105,361 shares of Iron Mountain Incorporated. This represents a change in shares of 0.28% during the quarter.

HighTower Advisors, LLC has a history of taking positions in derivatives of the underlying security (IRM1) in the form of stock options.

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 .

Institutional Put/Call Ratios
(Premium Subscription Required)

In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

MX:IRM1 / Iron Mountain Incorporated Historical Put/Call Ratio
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)
2026-05-05 2026-03-31 13F IRON MTN INC DEL COM 46284V101 105,660 299 0.28 10,792 23.48 0.0115
2026-02-06 2025-12-31 13F IRON MTN INC DEL COM 46284V101 105,361 -1,383 -1.30 8,740 -19.69 0.0096
2025-11-07 2025-09-30 13F IRON MTN INC DEL COM 46284V101 106,744 -3,344 -3.04 10,882 -3.63 0.0124
2025-08-11 2025-06-30 13F IRON MTN INC DEL COM 46284V101 110,088 964 0.88 11,292 20.27 0.0141
2025-05-13 2025-03-31 13F IRON MTN INC DEL COM 46284V101 109,124 23,580 27.56 9,389 4.42 0.0127
2025-02-07 2024-12-31 13F IRON MTN INC DEL COM 46284V101 85,544 -45,630 -34.79 8,992 -42.30 0.0123
2024-11-14 2024-09-30 13F IRON MTN INC DEL COM 46284V101 131,174 7,529 6.09 15,581 40.61 0.0223
2024-08-13 2024-06-30 13F IRON MTN INC DEL COM 46284V101 123,645 -9,744 -7.30 11,081 3.61 0.0171
2024-05-06 2024-03-31 13F IRON MTN INC DEL COM 46284V101 133,389 66,924 100.69 10,695 129.80 0.0173
2024-02-12 2023-12-31 13F IRON MTN INC DEL COM 46284V101 66,465 -92,565 -58.21 4,654 -50.76 0.0078
2023-11-08 2023-09-30 13F IRON MTN INC DEL COM 46284V101 159,030 92,924 140.57 9,451 151.29 0.0178
2023-08-14 2023-06-30 13F IRON MTN INC DEL COM 46284V101 66,106 -330 -0.50 3,761 7.06 0.0074
2023-05-12 2023-03-31 13F IRON MTN INC DEL COM 46284V101 66,436 1,929 2.99 3,513 9.30 0.0077
2023-02-09 2022-12-31 13F IRON MTN INC DEL COM 46284V101 64,507 -4,992 -7.18 3,214 5.27 0.0073
2022-11-09 2022-09-30 13F IRON MTN INC DEL COM 46284V101 69,499 3,526 5.34 3,053 -5.01 0.0082
2022-08-10 2022-06-30 13F IRON MTN INC COM 46284V101 65,973 -1,056 -1.58 3,214 -13.46 0.0083
2022-05-12 2022-03-31 13F IRON MTN INC COM 46284V101 67,029 2,017 3.10 3,714 9.14 0.0083
2022-02-10 2021-12-31 13F IRON MTN INC COM 46284V101 65,012 4,880 8.12 3,403 30.38 0.0075
2021-11-12 2021-09-30 13F IRON MTN INC COM 46284V101 60,132 -2,612 -4.16 2,610 -1.62 0.0070
2021-08-06 2021-06-30 13F IRON MTN INC COM 46284V101 62,744 -23,430 -27.19 2,653 -16.70 0.0077
2021-05-10 2021-03-31 13F IRON MTN INC COM 46284V101 86,174 -41,049 -32.27 3,185 -15.18 0.0101
2021-02-10 2020-12-31 13F IRON MTN INC COM 46284V101 127,223 27,059 27.01 3,755 40.01 0.0156
2020-11-13 2020-09-30 13F IRON MTN INC COM 46284V101 100,164 9,973 11.06 2,682 13.69 0.0130
2020-08-10 2020-06-30 13F IRON MTN INC COM 46284V101 90,191 14,097 18.53 2,359 30.33 0.0129
2020-05-21 2020-03-31 13F IRON MTN INC COM 46284V101 76,094 -326 -0.43 1,810 -25.70 0.0117
2020-02-14 2019-12-31 13F IRON MTN INC COM 46284V101 76,420 -12,651 -14.20 2,436 -15.42 0.0144
2019-11-12 2019-09-30 13F IRON MTN INC COM 46284V101 89,071 -53,563 -37.55 2,880 -35.24 0.0157
2019-08-13 2019-06-30 13F IRON MTN INC COM 46284V101 142,634 73,030 104.92 4,447 79.68 0.0265
2019-05-15 2019-03-31 13F IRON MTN INC COM 46284V101 69,604 18,076 35.08 2,475 48.92 0.0165
2019-02-14 2018-12-31 13F IRON MTN INC COM 46284V101 51,528 8,472 19.68 1,662 11.77 0.0127
2018-11-09 2018-09-30 13F IRON MTN INC COM 46284V101 43,056 824 1.95 1,487 0.00 0.0107
2018-08-14 2018-06-30 13F IRON MTN INC COM 46284V101 42,232 29,054 220.47 1,487 243.42 0.0116
2018-05-15 2018-03-31 13F IRON MTN INC COM 46284V101 13,178 -8,323 -38.71 433 -46.48 0.0036
2018-02-14 2017-12-31 13F IRON MTN INC COM 46284V101 21,501 -7,411 -25.63 809 -27.96 0.0066
2017-11-14 2017-09-30 13F IRON MTN INC COM 46284V101 28,912 9,784 51.15 1,123 70.93 0.0096
2017-09-22 2017-06-30 13F/A-1 IRON MTN INC COM 46284V101 19,128 325 1.73 657 -1.94 0.0059
2017-08-14 2017-06-30 13F IRON MTN INC COM 46284V101 19,128 325 657
2017-05-15 2017-03-31 13F IRON MTN INC COM 46284V101 18,803 4,958 35.81 670 49.22 0.0064
2017-02-10 2016-12-31 13F IRON MTN INC COM 46284V101 13,845 3,100 28.85 449 11.41 0.0049
2016-11-14 2016-09-30 13F IRON MTN INC COM 46284V101 10,745 -50,909 -82.57 403 -83.63 0.0047
2016-08-11 2016-06-30 13F IRON MTN INC COM 46284V101 61,654 -74,722 -54.79 2,462 -46.52 0.0311
2016-05-16 2016-03-31 13F IRON MTN INC COM 46284V101 136,376 80,724 145.05 4,604 207.34 0.0150
2016-05-18 2015-12-31 13F/A-1 IRON MTN INC COM 46284V101 55,652 -123,683 -68.97 1,498 -73.08 0.0178
2016-02-12 2015-12-31 13F IRON MTN INC COM 46284V101 55,652 1,498
2015-11-16 2015-09-30 13F IRON MTN INC COM 46284V101 179,335 21,025 13.28 5,565 13.39 0.0737
2015-08-11 2015-06-30 13F IRON MTN INC COM 46284V101 158,310 60,593 62.01 4,908 37.52 0.0787
2015-05-15 2015-03-31 13F IRON MTN INC COM 46284V101 97,717 32,039 48.78 3,569 40.57 0.0531
2015-02-17 2014-12-31 13F IRON MTN COM 462846106 65,678 65,678 2,539 0.0389
2014-11-14 2014-09-30 13F IRON MTN COM 462846106 0 -82,026 -100.00 0 -100.00
2014-08-13 2014-06-30 13F IRON MTN COM 462846106 82,026 71,170 655.58 2,908 872.58 0.0505
2014-05-15 2014-03-31 13F IRON MTN COM 462846106 10,856 -232 -2.09 299 -11.01 0.0058
2014-02-14 2013-12-31 13F IRON MTN COM 462846106 11,088 -1,264 -10.23 336 0.60 0.0069
2013-11-15 2013-09-30 13F IRON MTN COM 462846106 12,352 -29 -0.23 334 1.52 0.0084
2013-08-14 2013-06-30 13F IRON MTN COM 462846106 12,381 12,381 329 0.0089
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2025-05-13 2025-03-31 13F IRON MTN INC DEL COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2025-02-07 2024-12-31 13F IRON MTN INC DEL COM Put 23,800 262 n/a n/a n/a
2024-05-06 2024-03-31 13F IRON MTN INC DEL COM Put 0 -100.00 0 n/a n/a n/a
2024-02-12 2023-12-31 13F IRON MTN INC DEL COM Put 1,000 0 n/a n/a n/a
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.