# EDGAR Filing Document

**Accession Number:** 0001020569
**File Stem:** 0002045996-26-000004
**Filing Date:** 2026-3
**Character Count:** 12194
**Document Hash:** fedbd0ddc3a1cabf5328a09f57abbae1
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0002045996-26-000004.hdr.sgml**: 20260303

**ACCESSION NUMBER**: 0002045996-26-000004

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 3

**CONFORMED PERIOD OF REPORT**: 20260301

**FILED AS OF DATE**: 20260303

**DATE AS OF CHANGE**: 20260303

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Bhargava Mithu
- **CENTRAL INDEX KEY:** 0002045996

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-13045
- **FILM NUMBER:** 26717916

**MAIL ADDRESS:**
- **STREET 1:** C/O IRON MOUNTAIN INCORPORATED, 85 NEW H
- **STREET 2:** SUITE 150
- **CITY:** PORTSMOUTH
- **STATE:** NH
- **ZIP:** 03801
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** IRON MOUNTAIN INC
- **CENTRAL INDEX KEY:** 0001020569
- **STANDARD INDUSTRIAL CLASSIFICATION:** REAL ESTATE INVESTMENT TRUSTS [6798]
- **ORGANIZATION NAME:** 05 Real Estate & Construction
- **EIN:** 232588479
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 85 NEW HAMPSHIRE AVENUE, SUITE 150
- **STREET 2:** PEASE INTERNATIONAL TRADEPORT
- **CITY:** PORTSMOUTH
- **STATE:** NH
- **ZIP:** 03801
- **BUSINESS PHONE:** 617-535-4781

**MAIL ADDRESS:**
- **STREET 1:** 1101 ENTERPRISE DRIVE
- **CITY:** ROYERSFORD
- **STATE:** PA
- **ZIP:** 19468

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** IRON MOUNTAIN INC/PA
- **DATE OF NAME CHANGE:** 20000201

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** PIERCE LEAHY CORP
- **DATE OF NAME CHANGE:** 19960807

## Ex-24

![](poa-bhargave001.jpg)

POWER OF ATTORNEY KNOW ALL MEN BY THESE PRESENTS, that I, Mithu Bhargava, do hereby make, constitute and appoint Keely Stewart, Assistant Secretary of Iron Mountain Incorporated, Christine Zhang, Assistant Secretary of Iron Mountain Incorporated, and Luke Cummiskey, Director and Senior Counsel, each acting singly, to be my lawful attorney-in-fact for me and to do any and all acts which I could do in connection with any filings required by Section 16 of the Securities Exchange Act of 1934, including, without limitation, the preparation, signing and filing of Forms 3, 4 and 5 ("Section 16 Filings"). Among the powers granted to my attorney-in-fact are: To prepare, sign and file with the Securities and Exchange Commission and the New York Stock Exchange the Section 16 Filings, in my name or stead, and any and all such further documents as he/she may deem necessary or advisable in order to carry out the required Section 16 Filings and the powers granted to him/her by these presents. This Power of Attorney shall remain in effect until revoked by the undersigned in writing. IN WITNESS WHEREOF, I have hereunto set my hand and seal this 19th day of November, 2024. ______________________________ Name: Mithu Bhargava

------

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

[ ] Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Bhargava Mithu<br><sub>(Last) (First) (Middle)</sub><br>C/O IRON MOUNTAIN INCORPORATED<br>85 NEW HAMPSHIRE AVE, SUITE 150<br><sub>(Street)</sub><br>PORTSMOUTH, NH 03801<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-03-01 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [ ] 10% Owner<br>[X] Officer (give title below) [ ] Other (specify below)<br>_EVP, GM Digital Business Unit_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>IRON MOUNTAIN INC [ IRM ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| Common Stock, par value $.01 per share | 2026-03-01 |  | M |  | 51919<sup>(1)</sup> | A | $0 | 65174<sup>(2)</sup> | D |  |
| Common Stock, par value $.01 per share | 2026-03-01 |  | F |  | 25102<sup>(3)</sup> | D | $108.33 | 40072<sup>(2)</sup> | D |  |
| Common Stock, par value $.01 per share | 2026-03-01 |  | M |  | 61113<sup>(4)</sup> | A | $0 | 101185<sup>(2)</sup> | D |  |
| Common Stock, par value $.01 per share | 2026-03-01 |  | F |  | 28205<sup>(3)</sup> | D | $108.33 | 72980<sup>(2)</sup> | D |  |
| Common Stock, par value $.01 per share | 2026-03-01 |  | M |  | 2663<sup>(5)</sup> | A | $0 | 75643<sup>(2)</sup> | D |  |
| Common Stock, par value $.01 per share | 2026-03-01 |  | F |  | 1287<sup>(6)</sup> | D | $108.33 | 74356<sup>(2)</sup> | D |  |
| Common Stock, par value $.01 per share | 2026-03-01 |  | M |  | 2754<sup>(7)</sup> | A | $0 | 77110<sup>(2)</sup> | D |  |
| Common Stock, par value $.01 per share | 2026-03-01 |  | F |  | 1331<sup>(6)</sup> | D | $108.33 | 75779<sup>(2)</sup> | D |  |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| Performance Units | <sup>(8)</sup> | 2026-03-01 |  | M |  |  | 51919 | <sup>(9)</sup> | <sup>(9)</sup> | Common Stock, par value $.01 per share | 51919 | $0 | 0 | D |  |
| Performance Units | <sup>(8)</sup> | 2026-03-01 |  | M |  |  | 61113 | <sup>(10)</sup> | <sup>(10)</sup> | Common Stock, par value $.01 per share | 61113 | $0 | 0 | D |  |
| Restricted Stock Units | <sup>(11)</sup> | 2026-03-01 |  | M |  |  | 2663 | <sup>(12)</sup> | <sup>(12)</sup> | Common Stock, par value $.01 per share | 2663 | $0 | 0 | D |  |
| Restricted Stock Units | <sup>(11)</sup> | 2026-03-01 |  | M |  |  | 2754 | <sup>(13)</sup> | <sup>(13)</sup> | Common Stock, par value $.01 per share | 2754 | $0 | 5510 | D |  |
| Restricted Stock Units | <sup>(11)</sup> | 2026-03-01 |  | A |  | 9692 |  | <sup>(14)</sup> | <sup>(14)</sup> | Common Stock, par value $.01 per share | 9692 | $0 | 9692 | D |  |

---

### Footnotes:

(1) This acquisition is reported to reflect the full vesting of performance units ("PUs") previously granted to the Reporting Person on March 1, 2023. Effective February 16, 2026, the Compensation Committee of Iron Mountain Incorporated's Board of Directors determined the actual award of PUs under the grant after completion of the relevant performance period, and the PUs fully vested on March 1, 2026.

(2) Includes 201 shares of Common Stock acquired under the Iron Mountain Incorporated Employee Stock Purchase Plan since the last Section 16 filing by the Reporting Person.

(3) Represents the number of shares of Common Stock that have been withheld by the Issuer to satisfy its income tax withholding obligation in connection with the net settlement of the PUs and does not represent a sale.

(4) This acquisition is reported to reflect the full vesting of PUs previously granted to the Reporting Person on July 3, 2023. Effective February 16, 2026, the Compensation Committee of Iron Mountain Incorporated's Board of Directors determined the actual award of PUs under the grant after completion of the relevant performance period, and the PUs fully vested on March 1, 2026.

(5) This acquisition is reported to reflect the full vesting of restricted stock units ("RSUs") previously granted to the Reporting Person on March 1, 2023.

(6) Represents the number of shares of Common Stock that have been withheld by the Issuer to satisfy its income tax withholding obligation in connection with the net settlement of the RSUs and does not represent a sale.

(7) This acquisition is reported to reflect the partial vesting of RSUs previously granted to the Reporting Person on March 1, 2025.

(8) Each PU represents a contingent right to receive one share of Common Stock.

(9) The PUs were initially granted to the Reporting Person on March 1, 2023. Effective as of February 16, 2026, the Compensation Committee determined the actual award of PUs under the grant aftercompletion of the relevant performance period, and the PUs fully vested on March 1, 2026.

(10) The PUs were initially granted to the Reporting Person on July 3, 2023. Effective as of February 16, 2026, the Compensation Committee determined the actual award of PUs under the grant after completion of the relevant performance period, and the PUs fully vested on March 1, 2026.

(11) Each RSU represents a contingent right to receive one share of Common Stock.

(12) The RSUs, representing a contingent right to receive a total of 7,987 shares of Common Stock, were granted to the Reporting Person on March 1, 2023 and vest in three substantially equal annual installments beginning on the first anniversary of the grant date.

(13) The RSUs, representing a contingent right to receive a total of 8,264 shares of Common Stock, were granted to the Reporting Person on March 1, 2025 and vest in three substantially equal annual installments beginning on the first anniversary of the grant date.

(14) The RSUs, representing a contingent right to receive a total of 9,692 shares of Common Stock, were granted to the Reporting Person on March 1, 2026 and vest in three substantially equal annual installments beginning on the first anniversary of the grant date.

**Signature:** /s/ Christine Zhang, under Power of Attorney dated November 19, 2024, from Mithu Bhargava  
**Date:** 2026-03-03

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**