Skip to main content

Iron Mountain Inc

IRM
Exchange
NYSE
Industry
Real Estate Investment Trusts
SEC CIK
0001020569

In the last 90 days, Iron Mountain Inc insiders filed 0 open-market purchases and 7 sales; 1,177 institutions reported holding it in 13F filings for Q2 2026, worth $32.4B in total; no superinvestor holds it.

Four kinds of short-selling data, each measuring something different:

  • Short interest: shares sold short and not yet bought back, as of a settlement date. FINRA publishes it twice a month, about eight business days after the settlement date.
  • Daily short volume: shares sold short each day in off-exchange trades reported to FINRA. It counts trades, not open positions, and is published the next day.
  • Fails-to-deliver: shares not delivered by the settlement date. The SEC publishes them twice a month, about two weeks late.
  • ATS (dark pool) volume: weekly volume on alternative trading systems and other off-exchange venues. FINRA publishes it two to four weeks after the week.

More in the glossary.

Short interest

Shares sold short and not yet bought back, from FINRA, on every settlement date in the last two years.

Short interest
7.04M
Shares, settlement Oct 30, 2026
Change
−104.3K
−1.5% vs. Oct 15, 2026
Days to cover
5.56
Short interest ÷ average daily volume
Average daily volume
1.27M
Shares, as reported by FINRA
Short interest by settlement date
Oct 31, 2024: 9,267,997 sharesNov 15, 2024: 8,346,143 sharesNov 29, 2024: 8,365,000 sharesDec 13, 2024: 7,966,481 sharesDec 31, 2024: 7,540,708 sharesJan 15, 2025: 8,153,113 sharesJan 31, 2025: 8,040,973 sharesFeb 14, 2025: 8,683,441 sharesFeb 28, 2025: 9,032,044 sharesMar 14, 2025: 8,647,278 sharesMar 31, 2025: 9,657,633 sharesApr 15, 2025: 9,436,137 sharesApr 30, 2025: 10,258,438 sharesMay 15, 2025: 11,368,731 sharesMay 30, 2025: 9,456,156 sharesJun 13, 2025: 10,468,229 sharesJun 30, 2025: 7,964,361 sharesJul 15, 2025: 7,439,879 sharesJul 31, 2025: 6,992,274 sharesAug 15, 2025: 8,431,840 sharesAug 29, 2025: 8,650,084 sharesSep 15, 2025: 8,678,753 sharesSep 30, 2025: 8,066,615 sharesOct 15, 2025: 7,434,140 sharesOct 31, 2025: 7,673,493 sharesNov 14, 2025: 9,914,331 sharesNov 28, 2025: 9,901,708 sharesDec 15, 2025: 10,906,244 sharesDec 31, 2025: 9,637,754 sharesJan 15, 2026: 9,115,857 sharesJan 30, 2026: 9,157,943 sharesFeb 13, 2026: 7,821,452 sharesFeb 27, 2026: 7,584,704 sharesMar 13, 2026: 8,465,576 sharesMar 31, 2026: 8,188,431 sharesApr 15, 2026: 8,021,715 sharesApr 30, 2026: 7,641,375 sharesMay 15, 2026: 7,372,454 sharesMay 29, 2026: 7,300,638 sharesJun 15, 2026: 8,070,353 sharesJun 30, 2026: 7,458,588 sharesJul 15, 2026: 8,256,613 sharesJul 31, 2026: 8,378,595 sharesAug 14, 2026: 7,103,268 sharesAug 31, 2026: 6,463,287 sharesSep 15, 2026: 7,932,714 sharesSep 30, 2026: 6,999,689 sharesOct 15, 2026: 7,146,315 sharesOct 30, 2026: 7,042,041 shares
Short interest in IRM by settlement date
Settlement dateShort interestChangeChange %Avg. daily volumeDays to cover
Oct 30, 20267.04M−104.3K−1.5%1.27M5.56
Oct 15, 20267.15M+146.6K+2.1%1.39M5.13
Sep 30, 20267.00M−933.0K−11.8%1.65M4.24
Sep 15, 20267.93M+1.47M+22.7%1.69M4.69
Aug 31, 20266.46M−640.0K−9.0%1.36M4.75
Aug 14, 20267.10M−1.28M−15.2%1.82M3.90
Jul 31, 20268.38M+122.0K+1.5%1.87M4.47
Jul 15, 20268.26M+798.0K+10.7%2.42M3.41
Jun 30, 20267.46M−611.8K−7.6%1.85M4.03
Jun 15, 20268.07M+769.7K+10.5%1.30M6.22
May 29, 20267.30M−71.8K−1.0%1.22M5.99
May 15, 20267.37M−268.9K−3.5%1.69M4.36
Apr 30, 20267.64M−380.3K−4.7%1.97M3.89
Apr 15, 20268.02M−166.7K−2.0%1.16M6.94
Mar 31, 20268.19M−277.1K−3.3%1.54M5.31
Mar 13, 20268.47M+880.9K+11.6%1.37M6.17
Feb 27, 20267.58M−236.7K−3.0%2.04M3.71
Feb 13, 20267.82M−1.34M−14.6%2.60M3.01
Jan 30, 20269.16M+42.1K+0.5%1.91M4.80
Jan 15, 20269.12M−521.9K−5.4%2.03M4.49
Dec 31, 20259.64M−1.27M−11.6%2.12M4.55
Dec 15, 202510.9M+1.00M+10.2%1.93M5.64
Nov 28, 20259.90M−12.6K−0.1%3.14M3.16
Nov 14, 20259.91M+2.24M+29.2%2.25M4.40
Oct 31, 20257.67M+239.4K+3.2%987.9K7.77
Oct 15, 20257.43M−632.5K−7.8%1.41M5.29
Sep 30, 20258.07M−612.1K−7.1%1.68M4.80
Sep 15, 20258.68M+28.7K+0.3%1.64M5.30
Aug 29, 20258.65M+218.2K+2.6%1.03M8.39
Aug 15, 20258.43M+1.44M+20.6%1.95M4.33
Jul 31, 20256.99M−447.6K−6.0%910.4K7.68
Jul 15, 20257.44M−524.5K−6.6%1.36M5.47
Jun 30, 20257.96M−2.50M−23.9%2.18M3.65
Jun 13, 202510.5M+1.01M+10.7%1.36M7.67
May 30, 20259.46M−1.91M−16.8%1.64M5.77
May 15, 202511.4M+1.11M+10.8%1.63M6.99
Apr 30, 202510.3M+822.3K+8.7%1.48M6.93
Apr 15, 20259.44M−221.5K−2.3%2.34M4.04
Mar 31, 20259.66M+1.01M+11.7%1.79M5.41
Mar 14, 20258.65M−384.8K−4.3%2.70M3.20
Feb 28, 20259.03M+348.6K+4.0%2.78M3.25
Feb 14, 20258.68M+642.5K+8.0%1.91M4.54
Jan 31, 20258.04M−112.1K−1.4%1.95M4.13
Jan 15, 20258.15M+612.4K+8.1%1.99M4.11
Dec 31, 20247.54M−425.8K−5.3%2.08M3.63
Dec 13, 20247.97M−398.5K−4.8%1.63M4.88
Nov 29, 20248.37M+18.9K+0.2%1.15M7.29
Nov 15, 20248.35M−921.9K−10.0%1.83M4.56
Oct 31, 20249.27M+320.0K+3.6%1.35M6.87

Fails-to-deliver

Shares that weren't delivered by the settlement date, from the SEC, for the last 30 dates with fails. The price is the previous day's closing price published by the SEC.

Fails-to-deliver in IRM by settlement date
Settlement dateSharesPriceValue
Oct 9, 2026327$112.97$36.9K
Oct 6, 2026201$112.33$22.6K
Oct 2, 202614,779$111.13$1.64M
Sep 28, 20262$111.38$222.76
Sep 15, 202698$112.06$11.0K
Sep 8, 202628$116.86$3.27K
Aug 25, 2026501$121.19$60.7K
Aug 24, 2026123$122.02$15.0K
Aug 21, 2026330$122.94$40.6K
Aug 18, 20261,523$129.90$197.8K
Aug 4, 202654$124.08$6.70K
Jul 16, 20263,635$123.52$449.0K
Jun 30, 20265,187$129.97$674.2K
Jun 25, 202636,987$130.59$4.83M
Jun 22, 20263,581$127.83$457.8K
Jun 15, 20262,589$127.24$329.4K
Jun 12, 202611,140$125.17$1.39M
Jun 8, 202629$124.66$3.62K
May 29, 20263,943$126.83$500.1K
May 13, 202617$126.21$2.15K
May 8, 2026547$126.81$69.4K
May 4, 2026367$127.19$46.7K
Apr 29, 20264,792$112.62$539.7K
Apr 24, 20261,100$116.12$127.7K
Apr 20, 202613,069$118.07$1.54M
Apr 17, 20266,955$117.73$818.8K
Apr 15, 20263$114.03$342.09
Apr 6, 20268$103.30$826.4
Apr 2, 20262,278$100.95$230.0K
Mar 26, 2026714$100.53$71.8K

Daily short volume

Off-exchange short-sale volume, not short interest: shares sold short each day in trades reported to FINRA, for the last 30 trading days.

The short volume ratio isn't a sentiment gauge: market makers sell short to fill buy orders and to hedge, so short sales are usually about half of off-exchange volume.

Off-exchange short volume in IRM by trade date
Trade dateShort volumeShort exemptOff-exchange volumeShort volume ratio
Nov 10, 2026275,907559599,16346.0%
Nov 9, 2026593,471916855,55669.4%
Nov 6, 2026694,1133,0811,177,01459.0%
Nov 5, 20261,160,49119,4641,936,66559.9%
Nov 4, 2026470,009121,017,13146.2%
Nov 3, 2026250,6346586,20442.8%
Nov 2, 2026230,9546,922487,26947.4%
Oct 30, 2026255,990849412,42562.1%
Oct 29, 2026196,85726366,99953.6%
Oct 28, 2026366,1435499,40073.3%
Oct 27, 2026154,3602274,40956.3%
Oct 26, 2026213,24757354,43760.2%
Oct 23, 2026234,4334401,10458.4%
Oct 22, 2026518,1186704,51973.5%
Oct 21, 2026500,4849706,76770.8%
Oct 20, 2026442,619279874,99350.6%
Oct 19, 2026213,167942356,09659.9%
Oct 16, 2026281,64712579,20448.6%
Oct 15, 2026351,8891521,32467.5%
Oct 14, 2026292,1551,374379,06777.1%
Oct 13, 2026278,69031418,46266.6%
Oct 12, 2026226,5296317,72971.3%
Oct 9, 2026261,8140445,84558.7%
Oct 8, 2026606,7091,287759,21379.9%
Oct 7, 2026287,19677482,24759.6%
Oct 6, 2026252,026163468,30553.8%
Oct 5, 2026364,2401,089531,85568.5%
Oct 2, 2026355,1740609,54558.3%
Oct 1, 2026273,266567662,99841.2%
Sep 30, 2026151,2990612,63824.7%

ATS (dark pool) volume

Weekly volume on alternative trading systems (ATS) and other off-exchange (OTC) venues, from FINRA, for the last 12 weeks. ATS share is ATS volume ÷ (ATS + OTC volume), not a share of all trading.

Weekly ATS and OTC volume in IRM
Week ofTierATS sharesATS tradesOther OTC sharesOther OTC tradesATS share
Oct 19, 2026T12,088,87543,6331,655,90021,12155.8%
Oct 12, 2026T11,652,42943,554924,76116,09864.1%
Oct 5, 2026T12,143,80144,1651,128,93017,09265.5%
Sep 28, 2026T12,403,35147,1951,503,39120,05561.5%
Sep 21, 2026T11,991,44745,8031,291,02517,47860.7%
Sep 14, 2026T11,960,72249,7421,864,75619,57851.3%
Sep 7, 2026T11,389,53438,7601,082,92114,20956.2%
Aug 31, 2026T12,434,67652,5632,327,84319,45751.1%
Aug 24, 2026T11,946,98543,317691,03516,50473.8%
Aug 17, 2026T11,662,72646,3561,087,31217,12460.5%
Aug 10, 2026T11,914,99143,5171,172,83217,05062.0%
Aug 3, 2026T13,364,31165,1132,739,70318,30255.1%