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Iron Mountain Inc

Held by 9 tracked managers as of Q2 2026 · CUSIP ⓘCUSIP: A 9-character ID for one specific security - one share class of one company, or one bond. Tickers can change and can mean different things in different countries; a CUSIP always identifies exactly the same security, which is why filings use it. Guide 46284V101 · Sector ⓘGICS sectors: The 11-sector system most investors know (Global Industry Classification Standard): Technology, Health Care, Financials and so on. This site assigns each company a GICS-style sector from its SIC code, with a few hand corrections, so sector pages match the names investors expect. Guide

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In plain English: 9 of the investors we track own this stock. In the latest quarter, 3 of them bought more of it and 6 sold some or all of theirs (1 bought it for the first time). That tells you what they did last quarter — not what the stock will do next.

Educational and informational only, not personalized investment advice. Based on public filings that may be delayed or contain errors; verify with the original filings. Disclaimer

Managers holding
9
0 vs last quarter (like-for-like)
Total value held
$674.02M
Across tracked managers
Average weight ⓘOn average, how big this stock is in the portfolios that own it (its share of each manager's reported portfolio value).
0.0%
Of each manager's book
QoQ value ⓘLike-for-like: only managers that filed both quarters are compared, so a manager filing late (or confidentially) does not look like buying or selling. Includes price changes.
-$46.48M
-24.7% vs last quarter
Net shares bought
-720.5K
Est. net flow -$90.89M
Quarter activity
3 bought · 6 sold
1 new · 1 sold out

Tracked capital in this stock

Total value held (area) and number of managers (line). Dips can mean a large holder filed that quarter confidentially (e.g. Norges Bank in Q1/Q3).

Chart: Tracked capital in this stock

Aggregate buying and selling

Net share change reported each quarter

Chart: Aggregate buying and selling

Who owns IRM?

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Who owns IRM? — Q2 2026

Holders ranked by position size, with each one's quarter-over-quarter change.

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

# Manager Fund Shares Value ↓ % of their portfolio QoQ Δ shares Δ shares % Est. Δ value ⓘChange in shares × this quarter's price
1 Norges Bank Norges Bank Investment Management 4.21M $532.36M 0.1% — — — —
2 Ken Griffin Citadel Advisors 343.17K $43.35M 0.0% Reduced -31.8K -8.5% -$4.01M
3 Ron Baron Baron Capital (BAMCO) 310.72K $39.25M 0.1% Reduced -214.5K -40.8% -$27.10M
4 Israel Englander Millennium Management 157.06K $19.84M 0.0% Reduced -217.4K -58.1% -$27.46M
5 Steve Cohen Point72 Asset Management 123.26K $15.57M 0.0% Reduced -254.4K -67.4% -$32.13M
6 David Shaw D.E. Shaw & Co. 109.82K $13.87M 0.0% New +109.8K — +$13.87M
7 Two Sigma Two Sigma Investments 65.89K $8.32M 0.0% Reduced -113.3K -63.2% -$14.31M
8 Jim Simons Renaissance Technologies 7.70K $972.59K 0.0% Added +5.3K +220.8% +$669.44K
9 Ken Fisher Fisher Asset Management 3.95K $498.43K 0.0% Added +464 +13.3% +$58.61K

Sold out completely this quarter

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

Manager Fund Shares sold Value last quarter ↓
Ray Dalio Bridgewater Associates -4.7K $479.44K

Politician trades

Politician trades in IRM

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

No politician trades match these filters.