Iron Mountain (NYSE: IRM) director adds 459.793 phantom stock units

Rhea-AI Filing Summary

Iron Mountain Incorporated director Doyle R. Simons reported acquiring additional deferred equity-based compensation. On January 6, 2026, he received 459.793 units of phantom stock at a weighted average price of $84.625 per unit under the company’s Directors Deferred Compensation Plan. After this transaction, he beneficially owns 45,494.246 phantom stock units in total.

Each phantom stock unit is economically equivalent to one share of Iron Mountain common stock and will be paid out in common shares following Simons’ disability or when his board service ends. The new units also reflect dividends on common stock as if those dividends were reinvested in additional phantom stock.

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
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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^*

Simons Doyle

(Last) (First) (Middle)

C/O IRON MOUNTAIN INCORPORATED

85 NEW HAMPSHIRE AVENUE, SUITE 150

(Street)

PORTSMOUTH NH 03801

(City) (State) (Zip)

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)

3. Date of Earliest Transaction (Month/Day/Year)
01/06/2026

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

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

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

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)
			Code	V	Amount	(A) or (D)	Price

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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Phantom Stock	(1)	01/06/2026		A		459.793(2)		(1)	(1)	Common Stock	459.793	$84.625(3)	45,494.246	D

Explanation of Responses:

1. Pursuant to the Reporting Person's election to participate in the Iron Mountain Incorporated Directors Deferred Compensation Plan, the shares of phantom stock (the "Phantom Shares") will become payable in shares of Iron Mountain Incorporated common stock ("Common Stock") following the Reporting Person's disability or cessation of service as a director. Each Phantom Share is the economic equivalent of one share of Common Stock.

2. These shares give effect to dividends paid on Common Stock as if reinvested in Phantom Shares.

3. The price reported in Column 8 is a weighted average price. These shares of Common Stock were acquired in multiple transactions at prices ranging from $84.304 to $84.979, inclusive. The Reporting Person undertakes to provide the Company, any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares of Common Stock acquired at each separate price within the ranges set forth in this footnote (3).

Remarks:

	/s/ Keely Stewart, under Power of Attorney dated April 17, 2023 from Doyle R. Simons	01/08/2026
	** 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.

FAQ

What insider transaction did IRM director Doyle R. Simons report?

Director Doyle R. Simons reported acquiring 459.793 phantom stock units of Iron Mountain Incorporated on January 6, 2026, as disclosed in a Form 4 filing.

What is the total phantom stock beneficially owned by Doyle R. Simons after this IRM transaction?

Following the reported transaction, Doyle R. Simons beneficially owns 45,494.246 phantom stock units tied to Iron Mountain common stock.

At what price were the IRM phantom stock units acquired in this Form 4 filing?

The 459.793 phantom stock units were acquired at a weighted average price of $84.625 per unit, with underlying common share trades ranging from $84.304 to $84.979.

What does phantom stock mean for Iron Mountain (IRM) directors?

For Iron Mountain directors, each phantom stock unit is economically equivalent to one share of common stock and will be settled in common shares in the future.

When will Doyle R. Simons receive Iron Mountain (IRM) shares for his phantom stock?

The phantom stock units will become payable in Iron Mountain common stock after Doyle R. Simons experiences a disability or when his service as a director ceases.

How are dividends treated on Doyle R. Simons’ Iron Mountain phantom stock?

Dividends on Iron Mountain common stock are treated as if they were reinvested, increasing the number of phantom stock units held by Doyle R. Simons.