Iron Mountain Incorporated
Iron Mountain Incorporated (IRM) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · IRM · as of Mar 31, 2025
Ownership Breakdown
1,029
Institutional Holders
▼ 73 vs Q4
$21.11B
Total Inst. Value
▼ $3.81B vs Q4
297.52M
Shares Outstanding
freeFloat 99.05%
245.60M
13F Shares Held
▲ 8.45M vs Q4
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
IRM largest shareholders · institutional ownership
Q1 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
VANGUARD GROUP INC real estate investment trusts | 46.83M | 15.90% | 15.90% | $4.03T | May 9, 2025 | ▲ 220.6K |
BLACKROCK, INC. real estate investment trusts | 35.22M | 11.96% | 11.96% | $3.03T | May 2, 2025 | ▲ 3.15M |
STATE STREET CORP real estate investment trusts | 16.71M | 5.67% | 5.67% | $1.45T | May 15, 2025 | ▲ 83.3K |
COHEN & STEERS, INC. real estate investment trusts | 13.48M | 4.58% | 4.58% | $1.16T | May 15, 2025 | ▼ 1.43M |
GEODE CAPITAL MANAGEMENT, LLC real estate investment trusts | 8.28M | 2.81% | 2.81% | $715.89B | May 13, 2025 | ▲ 371.3K |
FMR LLC real estate investment trusts | 5.29M | 1.80% | 1.80% | $454.87B | May 12, 2025 | ▲ 4.62M |
NORTHERN TRUST CORP real estate investment trusts | 4.27M | 1.45% | 1.45% | $367.16B | May 13, 2025 | ▼ 59.2K |
DIMENSIONAL FUND ADVISORS LP real estate investment trusts | 4.26M | 1.45% | 1.45% | $366.21B | May 13, 2025 | ▲ 37.2K |
NORGES BANK real estate investment trusts | 3.69M | 1.25% | 1.25% | $317.61B | May 11, 2026 | ▲ 378.3K |
CHARLES SCHWAB INVESTMENT MANAGEMENT INC real estate investment trusts | 3.49M | 1.18% | 1.18% | $300.06B | Sep 15, 2025 | ▲ 8.7K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q1 2025 vs prior quarter
Q1 2025
30
Increased
+16.50M shares3
New Positions
first time holders17
Decreased
−5.37M shares0
Sold Out
fully exitedNet shares change (top 50)
+11.13M
+16.50M / −5.37M
Net new holders
+16
3 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
IRM insider trading · insider activity
Source: SEC Form 4
Insiders have been primarily selling shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
16
Buy transactions
19
Sell transactions
0.84
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Meaney William L President and CEO | Jun 1, 2026 | Sale | 10,156 | $126.20 | $1.28M | 28.3K | Form 4 ↗ |
Meaney William L President and CEO | Jun 1, 2026 | Sale | 10,457 | $127.00 | $1.33M | 17.9K | Form 4 ↗ |
Meaney William L President and CEO | Jun 1, 2026 | Sale | 7,523 | $127.90 | $962.2K | 10.3K | Form 4 ↗ |
Meaney William L President and CEO | Jun 1, 2026 | Sale | 9,247 | $129.14 | $1.19M | 1.1K | Form 4 ↗ |
Meaney William L President and CEO | Jun 1, 2026 | Sale | 1,091 | $129.66 | $141.5K | 0 | Form 4 ↗ |
Kidd Mark EVP, GM Data Centers & ALM | Jun 1, 2026 | Sale | 6,000 | $126.70 | $760.2K | 113.5K | Form 4 ↗ |
Borges Daniel SVP & Chief Accounting Officer | May 21, 2026 | Sale | 7,189 | $125.50 | $902.2K | 0 | Form 4 ↗ |
RAKOWICH WALTER C director | May 20, 2026 | Sale | 757 | $124.45 | $94.2K | 1.1K | Form 4 ↗ |
Arway Pamela M director | May 12, 2026 | Sale | 1,892 | $128.97 | $244.0K | 40.2K | Form 4 ↗ |
Meaney William L President and CEO | May 8, 2026 | Sale | 14,876 | $128.52 | $1.91M | 23.6K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
Iron Mountain Incorporated (IRM) is primarily owned by institutional investors, who hold approximately 82.5% of total shares outstanding. Company insiders own approximately 0.95%, while retail and public investors account for the remaining 16.50%.
The largest institutional shareholder of Iron Mountain Incorporated is VANGUARD GROUP INC, holding approximately 46.83 million shares — equal to 15.90% of outstanding shares — as of March 31, 2025.
A total of 1,029 institutional investors currently hold IRM stock, with a combined institutional value of approximately $21.11 billion as of the most recent 13F filing period.
Frequently asked questions
IRM ownershipIron Mountain Incorporated (IRM) is primarily owned by institutional investors, who hold approximately 82.5% of shares. The largest shareholder is VANGUARD GROUP INC with a 15.90% stake. Company insiders hold 0.95%. Data sourced from SEC Form 13F as of March 31, 2025.