Robin Matlock - 06 Jan 2026 Form 4 Insider Report for IRON MOUNTAIN INC (IRM)

Role
Director
Signature
/s/ Christine Zhang, under Power of Attorney dated May 12, 2025 from Robin Matlock
Issuer symbol
IRM
Transactions as of
06 Jan 2026
Net transactions value
+$862
Form type
4
Filing time
08 Jan 2026, 17:26:21 UTC
Previous filing
06 Jan 2026
Next filing
22 Jan 2026

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Matlock Robin Director C/O IRON MOUNTAIN INCORPORATED, 85 NEW HAMPSHIRE AVENUE, SUITE 150, PORTSMOUTH /s/ Christine Zhang, under Power of Attorney dated May 12, 2025 from Robin Matlock 08 Jan 2026 0001781215

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction IRM Phantom Stock Award $862 +10 $84.62 10 06 Jan 2026 Common Stock 10 Direct F1, F2, F3
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Pursuant to the Reporting Person's election to participate in the Iron Mountain Incorporated Directors Deferred Compensation Plan (the "Plan"), the shares of phantom stock (the "Phantom Shares") will become payable in shares of Iron Mountain Incorporated common stock ("Common Stock") on various dates selected by the Reporting Person or as otherwise provided in the Plan. Each Phantom Share is the economic equivalent of one share of Common Stock.
F2 These shares give effect to dividends paid on Common Stock as if reinvested in Phantom Shares.
F3 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).