IRON MOUNTAIN (IRM) director granted 1,892 RSU-based shares, now holds 3,211

Filing Impact

(Neutral)

Filing Sentiment

(Neutral)

Form Type

Rhea-AI Filing Summary

Kelly Christie B. reported acquisition or exercise transactions in this Form 4 filing.

IRON MOUNTAIN INC director Kelly Christie B. received an equity grant on May 7, 2026. The filing reports an award of 1,892 shares of common stock, delivered as restricted stock units that vested in full on the grant date at no cash cost per share.

After this grant and related dividend accruals, Christie directly holds 3,211.061 shares of IRON MOUNTAIN common stock. This total includes 11.061 additional shares credited for dividend reinvestment since the last reported transaction, which are treated as exempt under Rule 16a-11.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Kelly Christie B.

Role null

Type	Security	Shares	Price	Value
Grant/Award	Common Stock, par value $.01 per share	1,892	$0.00	--

Holdings After Transaction: Common Stock, par value $.01 per share — 3,211.061 shares (Direct, null)

Footnotes (1)

Consists of shares issuable upon the settlement of restricted stock units ("RSUs") granted on May 7, 2026. The RSUs vest in their entirety on the grant date. Includes 11.061 shares for accrued dividends pursuant to dividend reinvestment since the last reported transaction and exempt from Rule 16a-11.

Key Figures

RSU grant size: 1,892 shares Shares owned after grant: 3,211.061 shares Dividend reinvestment shares: 11.061 shares +1 more

4 metrics

RSU grant size 1,892 shares Restricted stock units granted on May 7, 2026

Shares owned after grant 3,211.061 shares Total direct common stock holdings after transaction

Dividend reinvestment shares 11.061 shares Accrued via dividend reinvestment since last reported transaction

Grant price per share $0.0000 per share Compensation grant, not open-market purchase

Key Terms

restricted stock units ("RSUs"), dividend reinvestment, Rule 16a-11

3 terms

restricted stock units ("RSUs") financial

"Consists of shares issuable upon the settlement of restricted stock units ("RSUs") granted on May 7, 2026."

Restricted stock units (RSUs) are a company promise to give an employee shares of stock (or cash equivalent) in the future, but only after certain conditions—usually staying with the company for a set time or hitting performance goals—are met. Investors watch RSUs because when they vest they increase the number of shares outstanding and can lead insiders to sell shares, affecting share price, company dilution and the true cost of employee pay.

dividend reinvestment financial

"Includes 11.061 shares for accrued dividends pursuant to dividend reinvestment since the last reported transaction"

Dividend reinvestment is when the money earned from a company's profit sharing, called dividends, is automatically used to buy more shares of that company instead of being received as cash. This process helps investors grow their holdings over time without extra effort, much like using earned interest to buy more of a savings account. It encourages long-term investment growth by continuously increasing the amount of shares owned.

Rule 16a-11 regulatory

"accrued dividends pursuant to dividend reinvestment since the last reported transaction and exempt from Rule 16a-11."

Form 4 Insider Transactions: What Each Field Means →

05/11/2026 - 05:06 PM

SEC Form 4

FORM 4

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

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^*

Kelly Christie B.

(Last)

(First)

(Middle)

C/O IRON MOUNTAIN INCORPORATED

85 NEW HAMPSHIRE AVENUE, SUITE 150

(Street)

PORTSMOUTH

NEW HAMPSHIRE

03801

(City)

(State)

(Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
IRON MOUNTAIN INC [ IRM ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	10% Owner
	Officer (give title below)	Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/07/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock, par value $.01 per share	05/07/2026		A		1,892⁽¹⁾	A	$0	3,211.061⁽²⁾	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

Explanation of Responses:

1. Consists of shares issuable upon the settlement of restricted stock units ("RSUs") granted on May 7, 2026. The RSUs vest in their entirety on the grant date.

2. Includes 11.061 shares for accrued dividends pursuant to dividend reinvestment since the last reported transaction and exempt from Rule 16a-11.

Remarks:

	/s/ Christine Zhang, under Power of Attorney dated September 11, 2025, from Christie Kelly	05/11/2026
	** Signature of Reporting Person	Date
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.
* Form 4: SEC 1474 (03-26)

Source: View Original Filing on SEC EDGAR

FAQ

What insider transaction did IRON MOUNTAIN (IRM) report for Kelly Christie B.?

IRON MOUNTAIN reported that director Kelly Christie B. received an equity grant of 1,892 shares of common stock on May 7, 2026. The shares were issued as restricted stock units that vested immediately, increasing her direct ownership position in the company.

How many IRON MOUNTAIN (IRM) shares does Kelly Christie B. own after this Form 4 filing?

Following the reported grant, Kelly Christie B. directly owns 3,211.061 IRON MOUNTAIN common shares. This figure includes the 1,892-share award and 11.061 shares credited for dividend reinvestment since her last reported transaction, as disclosed in the filing’s footnotes.

What type of equity award did IRON MOUNTAIN (IRM) grant to Kelly Christie B.?

The award consists of shares issuable upon settlement of restricted stock units, or RSUs, granted on May 7, 2026. The filing states that these RSUs vest in their entirety on the grant date, effectively delivering 1,892 common shares to the director immediately.

Was there any purchase price for the IRON MOUNTAIN (IRM) shares granted to Kelly Christie B.?

The reported transaction price per share is $0.0000, indicating the grant was compensation-based rather than an open-market purchase. Such director awards typically reflect board service compensation rather than discretionary buying decisions in the public market.

What are the additional 11.061 IRON MOUNTAIN (IRM) shares mentioned in the Form 4?

The Form 4 notes that 11.061 shares are included for accrued dividends through dividend reinvestment since the last reported transaction. These dividend-based shares are described as exempt from Rule 16a-11, meaning they are treated differently from standard open-market transactions.