---
schema_version: "secwatch.filing_event.v1"
accession: "0001020569-26-000016"
form_type: "8-K"
ticker: "IRM"
cik: "0001020569"
company_name: "IRON MOUNTAIN INC"
filed_at: "2026-03-09T23:59:59+00:00"
generated_at: "2026-05-15T17:26:29.757661+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.35
calibrated_materiality_score: 0.35
confidence: "high"
source: SEC EDGAR
---

# Iron Mountain updates REIT tax disclosure; counsel opines on qualification from 2014-2025

## Summary
- Filed updated material U.S. federal income tax considerations for REIT status and stock ownership.
- Sullivan & Worcester LLP opinion states Iron Mountain has qualified as a REIT for 2014-2025 and expects to continue.
- Summary replaces prior tax descriptions; covers REIT requirements, distribution rules, and tax consequences for stockholders.
- Company cautions that IRS challenges or changes in law could affect REIT qualification, with potential corporate-level tax.
- Ownership restrictions in charter aim to prevent concentrated ownership that would jeopardize REIT status.

## SEC filing metadata
- accession: 0001020569-26-000016
- form_type: 8-K
- ticker: IRM
- cik: 0001020569
- company_name: IRON MOUNTAIN INC
- filed_at: 2026-03-09T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.35
- calibrated_materiality_score: 0.35
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1020569/000102056926000016/0001020569-26-000016-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1020569/000102056926000016/irm-20260309.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001020569-26-000016
- JSON: https://secwatch.observer/filing/0001020569-26-000016.json
- Plain text: https://secwatch.observer/filing/0001020569-26-000016.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.