Quick Takeaways
- VANGUARD PORTFOLIO MANAGEMENT LLC filed SCHEDULE 13G for Iron Mountain Inc Common Stock (IRM).
- Disclosed ownership: 8.4%.
- Date of event: 31 Mar 2026.
VANGUARD PORTFOLIO MANAGEMENT LLC - 31 Mar 2026 SCHEDULE 13G Report for Iron Mountain Inc Common Stock (IRM)
- Filing Manager
- VANGUARD PORTFOLIO MANAGEMENT LLC
- Reporting Manager
- Vanguard Portfolio Management
- Security
- Iron Mountain Inc Common Stock
- Symbol
- IRM
- Shares outstanding
- 297,519,418 shares
- Disclosed Ownership
- 25,051,135 shares
- Ownership
- 8.4%
- Form type
- SCHEDULE 13G
- Filing time
- 29 Apr 2026, 14:10:15 UTC
- Date of event
- 31 Mar 2026
- SEC
- View on sec.gov
Quoteable Key Fact
"VANGUARD PORTFOLIO MANAGEMENT LLC disclosed 8.4% ownership in Iron Mountain Inc Common Stock (IRM) on 31 Mar 2026."
What Changed
- No earlier schedule filing is available for direct comparison.
- Current filing was accepted on 29 Apr 2026, 14:10.
Why This Matters
- This page explains what this Schedule 13D/13G filing tells you before manager-level rows.
- You can verify ownership claims directly against the original SEC filing.
Source Evidence
Backed by Schedule 13D/13G
See Original Filing
Beneficial ownership values are sourced from the original SEC Schedule 13D/13G filing.
Reporting Managers (1)
| Name | Ownership | Shares Owned | sole voting power | shared voting power | Signature | Title | CIK |
|---|---|---|---|---|---|---|---|
| Vanguard Portfolio Management | 8.4% | 25,051,135 | 35,578 | 0 | Ashley Grim | Head of Global Fund Administration |