Mariner
IRM icon

Mariner’s Iron Mountain IRM Stock Holding History

Mariner’s Portfolio IRM Stock Details IRM Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$13.2M Buy
129,019
+65,684
+104% +$6.53M 0.02% 630
2025
Q4 		$5.26M Buy
63,335
+16,381
+35% +$1.53M 0.01% 983
2025
Q3 		$4.79M Buy
46,954
+1,299
+3% +$125K 0.01% 944
2025
Q2 		$4.68M Buy
45,655
+4,035
+10% +$380K 0.01% 895
2025
Q1 		$3.58M Sell
41,620
-8,214
-16% -$792K 0.01% 946
2024
Q4 		$5.24M Buy
49,834
+3,154
+7% +$371K 0.01% 784
2024
Q3 		$5.54M Buy
46,680
+5,702
+14% +$610K 0.01% 744
2024
Q2 		$3.67M Sell
40,978
-1,108
-3% -$89.7K 0.01% 850
2024
Q1 		$3.38M Sell
42,086
-1,036
-2% -$75K 0.01% 878
2023
Q4 		$3.02M Buy
43,122
+7,860
+22% +$493K 0.01% 877
2023
Q3 		$2.1M Sell
35,262
-281
-0.8% -$17.2K 0.01% 952
2023
Q2 		$2.02M Buy
35,543
+303
+0.9% +$16.6K 0.01% 974
2023
Q1 		$1.86M Buy
35,240
+949
+3% +$49.7K 0.01% 990
2022
Q4 		$1.71M Buy
34,291
+11,975
+54% +$605K 0.01% 991
2022
Q3 		$981K Buy
22,316
+3,593
+19% +$181K ﹤0.01% 1060
2022
Q2 		$912K Sell
18,723
-629
-3% -$33.1K ﹤0.01% 931
2022
Q1 		$1.07M Buy
19,352
+204
+1% +$9.72K ﹤0.01% 915
2021
Q4 		$1M Buy
19,148
+819
+4% +$38.7K ﹤0.01% 828
2021
Q3 		$797K Buy
18,329
+1,536
+9% +$69.1K ﹤0.01% 751
2021
Q2 		$711K Buy
16,793
+4,381
+35% +$184K ﹤0.01% 736
2021
Q1 		$459K Sell
12,412
-844
-6% -$28.2K ﹤0.01% 755
2020
Q4 		$391K Buy
+13,256
New +$368K ﹤0.01% 711
2019
Q2 		– Sell
-5,912
Closed -$210K – 1132
2019
Q1 		$210K Buy
+5,912
New +$209K ﹤0.01% 952

Other funds holding IRM

BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
VPM
Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
State Street
State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return
Cohen & Steers
Cohen & Steers New York $57.6B AUM 8.03% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return
Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return
Morgan Stanley
Morgan Stanley New York $1.66T AUM 25.57% 1-Year Est. Return
Principal Financial Group
Principal Financial Group Des Moines, Iowa $187B AUM 18.48% 1-Year Est. Return
Dimensional Fund Advisors
Dimensional Fund Advisors Austin, Texas $481B AUM 30.42% 1-Year Est. Return

Mariner's IRM Position: Q1 2026 in Review

Mariner increased its Iron Mountain (IRM) stake by 104% in Q1 2026, buying an estimated $6.53M and bringing the position to 129,019 shares worth $13.2M. The position accounts for 0.02% of the portfolio, ranked #630.

Mariner first reported a position in IRM in Q1 2019 and has held it in 23 quarters since. 1,082 funds tracked by Wall St. Rank hold IRM as of Q1 2026.

  • Mariner held 129,019 shares of Iron Mountain worth $13.2M as of Q1 2026.
  • Mariner bought 65,684 Iron Mountain shares in Q1 2026, an estimated $6.53M.
  • Iron Mountain made up 0.02% of Mariner's portfolio in Q1 2026, its #630 holding.
  • Mariner first reported a position in Iron Mountain in Q1 2019 and has held it in 23 quarters since.
  • 1,082 funds tracked by Wall St. Rank held Iron Mountain as of Q1 2026.

Based on Mariner's 13F filing for Q1 2026, filed 13 May 2026.